ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Dinâmica da comunidade de Chironomidae (Diptera) em eventos de cheias e secas extremas em um rio Neotropical. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-05-04
    Description: Climate change can make extreme drought and flood events more frequent, while damming large rivers can alter the hydrological regime by making droughts more prolonged and floods less intense. Together, both factors can affect aquatic communities. Here, the variation of Chironomidae community attributes between extreme floods and droughts in a neotropical floodplain river was investigated. The hypothesis that the abundance, richness, diversity and variability attributes of the Chironomidae community are reduced after extreme events was tested. Sampling took place quarterly from 2000 to 2012, although only a few years were selected to investigate our predictions. Twelve sampling periods were selected, which were divided into years in which, El Niño (extreme flood) and La Niña (extreme drought) phenomena occurred. In the Paraná River, three points were determined for the collection of benthic material, in transect: right bank, center and left bank of the river. We recorded 75 morphospecies of Chironomidae. The most common taxa in periods of extreme flooding were Djalmabatista sp 2, Lopescladius sp 1 and Tanytarsus type E. For periods of extreme drought, the most common taxa were Polypedilum (Tripodura) sp 4, Polypedilum sp 3 and Lopescladius sp 1. A composition and attributes of the Chironomidae community in the Paraná River varied between before and after extreme flood and drought events. Attributes such as Shannon-Wiener abundance, richness and diversity were reduced after extreme floods and, in contrast, tended to increase after extreme drought events (except Shannon diversity). Thus, it can be stated that the evaluated flood and drought events, despite being extreme, have different consequences in the Chironomidae community of the Paraná River. Given the environmental and global conditions we experience today, including climate change and dams, extreme events could be even more frequent in aquatic ecosystems. Therefore, it is essential to understand the consequences of extreme flood and drought events on ecosystems with high biodiversity and that provide relevant ecosystem services such as floodplain rivers.
    Description: As mudanças climáticas podem tornar eventos de secas e cheias extremas mais frequentes, enquanto barramentos de grandes rios podem alterar o regime hidrológico por tornar as secas mais prolongadas e as cheias menos intensas. Em conjunto, ambos fatores podem afetar as comunidades aquáticas. Aqui, a variação dos atributos da comunidade de Chironomidae entre as cheias e secas extremas em um rio de planície de inundação neotropical. Testou-se a hipótese de que os atributos abundância, riqueza, diversidade e variabilidade da comunidade de Chironomidae são reduzidos após eventos extremos. As amostragens ocorreram trimestralmente 2000 a 2012, embora apenas alguns anos foram selecionados para investigar nossas predições. Selecionou-se 12 períodos de amostragem, que foram divididos em anos que ocorreram fenômenos de El Niño (cheia extrema) e La Niña (seca extrema). No rio Paraná foram determinados três pontos para coleta do material bentônico, em transecto: margem direita, centro e margem esquerda do rio. Registrou-se 75 morfoespécies de Chironomidae. Os táxos mais comuns nos períodos de cheia extrema foram Djalmabatista sp 2, Lopescladius sp 1 e Tanytarsus tipo E. Para os períodos de seca extrema, os táxons mais comuns foram Polypedilum (Tripodura) sp 4, Polypedilum sp 3 e Lopescladius sp 1. A composição e os atributos da comunidade de Chironomidae no rio Paraná variaram entre antes e depois de eventos de cheia e seca extremas. Os atributos, como abundância, riqueza e diversidade de Shannon-Wiener, foram reduzidos após cheias extremas e em contrapartida, tenderam a aumentar após eventos de seca extrema (exceto diversidade de Shannon). Pode-se afirmar que os eventos de cheias e secas avaliados, apesar de extremos, acarretam em diferentes consequências na comunidade de Chironomidae do rio Paraná. Considerando que as condições ambientais e globais que vivenciamos hoje, incluindo mudanças climáticas e barragens, os eventos extremos poderão ser ainda mais frequentes nos ecossistemas aquáticos. Portanto, é fundamental compreendermos as consequências dos eventos de cheia e seca extremas em ecossistemas com elevada biodiversidade e que fornecem relevantes serviços ecossistêmicos como rios de planícies de inundação.
    Description: Masters
    Keywords: Chironomidae (Diptera: Insecta) ; Zoobentos de água doce ; Comunidades, Ecologia de ; Pulso de inundação ; Mudanças climáticas ; ASFA_2015::Y::Zoobenthos ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::F::Floodplains ; ASFA_2015::C::Climatic changes
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 26pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 2
    facet.materialart.
    Unknown
    Sucessão de macroinvertebrados na decomposição da planta aquática exótica Hydrilla verticillata e da nativa Egeria najas. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-05-04
    Description: Decomposition is a process of great importance to the ecosystem. Macroinvertebrates together with fungi and bacteria play a very important role in the cycling of organic matter. Through decomposition, nutrients that make up the organisms can be reused and macroinvertebrates act by fractionating the organic matter in this process. The exotic species Hydrilla verticillata (L.f) Royle usually causes problems in various regions of the globe such as economic damage in hydroelectric plants. This exotic species competes with native species and can facilitates new invasions. The objective of the present work is to evaluate how the colonization of macroinvertebrates occurs during the decomposition of H. verticillata and E. najas macrophytes, as well as other community attributes during the process such as density, richness, Shannon diversity and Pielou evenness. The experiment was carried out in Garças Lake and the macrophytes were collected in Paraná River. Macrophytes were dried at room temperature and 5 g of each species were added in two types of litterbags, one thin mesh (0.5 mm) and another with thick mesh (4 mm), totalling 100 litterbags. The litterbags were fixed at 5 points in the lake and removed each 4 days. In the laboratory the litterbags were washed with a 0.2 μm mesh sieve, the decomposing material was sorted and the remainder was oven dried for further decay calculation. There was no significant difference in community attributes, except when time was applied assigned to analysis. The decomposition was similar in both species because both had similar characteristics, including phylogenetic proximity. The most observed taxon during the process was Chironomidae. Thus, it is worth noting that more studies are needed to elucidate questions related to the colonization process and quantify the degradation of organic matter of exotic and native species in the Upper Paraná River floodplain.
    Description: A decomposição é um processo de grande importâcia para os ecossistemas, e os macroivertebrados juntamente com fungos e bactérias possuem um importante papel na ciclagem da matéria orgânica. Pela decomposição, os nutrientes que compõem os organismos podem ser novamente reutilizados, e os macroinvertebrados atuam fracionando essa matéria orgânica. A espécie exótica Hydrilla verticillata (L.f) Royle é uma espécie de macrófita submersas que atualmente tem causado problemas em diversas regiões do globo. Além de causar prejuízos econômicos em usinas hidroelétricas H. verticillata causa prejuízos para as espécies nativas devido a competição por recursos, o que pode facilitar novas invasões. Avaliou-se como ocorre a colonização de macroinvertebrados durante a decomposição das macrófitas H. verticillata e E. najas, além de avaliar outros atributos de comunidade durante o processo como, por exemplo, densidade, riqueza, diversidade de Shannon e equitabilidade de Pielou. O experimento foi realizado na Lagoa das Garças e as macrófitas foram coletadas no Rio Paraná. Após a coleta, as plantas foram secas em temperatura ambiente. Foram acondicionadas 5 g de material seco de cada espécie em dois tipos de litterbag, um com malha fina (0,5mm) e outro com malha grossa (4 mm), totalizando 100 litterbags. Os litterbags foram fixados em 5 pontos na lagoa e retirados em um intervalo de 4 em 4 dias. Em laboratório, os litterbags foram lavados com auxílio de peneira de malha de 0,2 μm. O material em decomposição foi triado e o restante foi seco em estufa para posterior cálculo de decaimento. Não houve diferença significativa nos atributos de comunidade, exceto quando o tempo foi aplicado como uma variável à análise. A decomposição foi similar nas duas espécies devido a ambas possuírem características semelhantes. Talvez, a proximidade filogenética entre as macrófitas possa ter gerado a similaridade dos resultados obtidos durante o experimento. O táxon mais observado durante o processo foi de Chironomidae e o processo de colonização ocorreu de forma muito semelhante para ambos os tratamentos. Os tipos de malhas mostraram resultados parecidos, pois podem não ter influenciado a colonização e a entrada dos macroinvertebrados durante o processo de decomposição. Desse modo, a colonização dos invertebrados não dependeu das espécies de macrófita e/ou tipo de malha. Por isso ressalta-se a importância de novos estudos para melhor direcionar questões voltadas para a colonização e quantificar a degradação da matéria orgânica relativa a espécies exóticas e nativas na planície de inundação do alto rio Paraná.
    Description: Masters
    Keywords: Macroinvertebrados de água doce ; Colonização ; Lagos rasos ; Indicadores biológicos ; Macrófitas aquáticas submersas ; Decomposição ; Ecologia de lagos rasos ; Processos ecossistêmicos ; ASFA_2015::M::Macrophytes ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Floodplains ; ASFA_2015::D::Decomposition ; ASFA_2015::C::Colonization ; ASFA_2015::L::Lakes
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 25pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 3
    facet.materialart.
    Unknown
    Larvas de Limnoperna fortunei (Dunker, 1857): dos filtros abióticos aos impactos potenciais sobre a comunidade de fitoplâncton. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-05
    Description: The success of biological invasions depends on overcoming environmental filters. After the filters are transposed and subsequently established, invasive species can reach high densities and cause impacts, such as loss of biodiversity and damage to the functioning of ecosystems. The golden mussel (Limnoperna fortunei) is an invasive bivalve in South America and presents high densities in invaded environments. It has a planktonic larval stage, divided into five stages, and an encrusting adult. The larval stage is considered the main propagule of the species. It is known that abiotic factors act differently on larval stages, as these present morphological and physiological differences. Some works shown the ability of L. fortunei to select groups and functional traits of phytoplankton species, but these studies are experimental and with adult representatives. Considering that larvae are the main propagule of the species, therefore, abiotic filters act primarily on them, we sought to (i) evaluate the population structure of L. fortunei larvae and its relationship with environmental factors in lotic environments in the floodplain of the Upper Paraná River. In addition, considering that larvae can reach high density values, we also sought to (ii) identify the potential impacts of high larval densities on the taxonomic and functional diversity of phytoplankton, and their effects on ecosystem functioning. The results showed differences in the age pyramid between the evaluated environments, and found that most environmental filters act on the early larval stages. Among these filters, turbidity stands out. We also identified a negative effect of L. fortunei larval density on the functional and taxonomic diversity of the phytoplankton community. The effects of larval density on these facets of phytoplankton diversity resulted in indirect negative effects on the biomass stock of the community of these producers. It's expected that knowledge about the filters that control larval densities of L. fortunei can contribute to the control and management of the species, in order to avoid major impacts on the phytoplankton, and consequently, on the environment.
    Description: O sucesso das invasões biológicas depende da superação filtros ambientais. Após a transposição dos filtros e consequente estabelecimento, as espécies invasoras podem atingir altas densidades e ocasionar impactos, como perda de biodiversidade e prejuízos ao funcionamento dos ecossistemas. O mexilhão-dourado (Limnoperna fortunei) é um bivalve invasor na América do Sul e apresenta elevadas densidades nos ambientes invadidos. Apresenta fase larval planctônica, dividida em cinco estágios, e adulta incrustante. A fase larval é considerada o principal propágulo da espécie. É sabido que os fatores abióticos atuam diferentemente sobre os estágios larvais, dado que estes apresentam diferenças morfológicas e fisiológicas. Alguns trabalhos evidenciaram a capacidade de L. fortunei em selecionar grupos e traços funcionais das espécies de fitoplâncton, porém esses estudos são experimentais e com representantes adultos. Considerando que as larvas são o principal propágulo da espécie, logo, os filtros abióticos agem primariamente sobre elas e buscou-se (i) avaliar a estruturação populacional das larvas de L. fortunei e sua relação com os fatores ambientais em ambientes lóticos da planície de inundação do alto rio Paraná. Ainda, considerando que as larvas podem atingir elevados valores de densidade também buscou-se (ii) identificar os potenciais impactos das altas densidades larvais sobre a diversidade taxonômica e funcional de fitoplâncton, e seus reflexos sobre o funcionamento ecossitêmico. Os resultados evidenciaram diferenças na pirâmide etária entre os ambientes avaliados, e constatou-se que a maioria dos filtros ambientais age sobre os estágios larvais iniciais. Dentre esses filtros, destaca-se a turbidez. Também identificou-se o efeito negativo da densidade larval de L. fortunei sobre a diversidade funcional e taxonômica da comunidade de fitoplâncton. Os efeitos da densidade larval sobre essas facetas da diversidade do fitoplâncton resultaram em efeitos negativos indiretos sobre o estoque de biomassa da comunidade desses produtores. Espera-se que o conhecimento sobre os filtros que controlam as densidades larvais de L. fortunei possa contribuir para o controle e manejo da espécie, a fim de evitar maiores impactos sobre o fitoplancton, e consequentemente, sobre o ambiente.
    Description: PhD
    Keywords: Limnoperna fortunei (Dunker, 1857) (Bivalve) "mexilhão-dourado" ; Moluscos límnicos invasores ; Bivalves límnicos invasores ; Larvas ; Invasores biológicos ; Diversidade taxonômica e funcional ; Filtros ambientais ; ASFA_2015::P::Phytoplankton ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::I::Impacts ; ASFA_2015::A::Alien species ; ASFA_2015::M::Molluskan larvae ; ASFA_2015::F::Floodplains ; ASFA_2015::T::Taxonomy
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 75pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 4
    facet.materialart.
    Unknown
    Descrição de sete novas espécies e dois novos gêneros de Physocypria sensu latu (Crustacea, Ostracoda) de planícies de inundação brasileiras. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-05
    Description: We describe seven new species of Physocypria sensu latu from three of the main Brazilian floodplains: Gen. 1 spec. A gen. et spec. nov. and Gen. 1 spec. B gen. et spec. nov. from the Upper Paraná River floodplain and the South Matogrossense Pantanal, Gen. 2 spec. C gen. et spec. nov., Gen. 1 spec. D gen. et spec. nov. and Gen. 2 spec. E gen. et spec. nov. from the South Matogrossense Pantanal only and Gen. 1 spec. F gen. et spec. nov. and Gen. 1 spec. G gen. et spec. nov. only from the Amazon River floodplain. All new species here described were found in sexual populations. Generally, the new species have a short and suboval carapace, with the left valve overlapping the right valve on all sides, except for the dorsal side in some species. The morphology of hemipenis and prehensile palps, together with the shape of the valves, were most important to distinguish the species. However, several other morphological characters from limb chaetotaxy are discussed, e.g., the absence in all new species of the short accompanying seta of the five natatory setae on antenna; the presence in all new species of a long seta next to the two a-seta on the first thoracopod and the presence/absence or length of specific setae on second and third thoracopod. We discuss the taxonomic position of the seven new species by evaluating the validity of extant genera, especially of Keysercypria Karanovic, 2011, and foreshadow that our seven new species represent two new genera of Cyclocypridinae.
    Description: Sete novas espécies de Physocypria sensu latu foram descritas de três das principais planícies brasileiras: Gen. 1 spec. A gen. et spec. nov. e Gen. 1 spec. B gen. et spec. nov. da planície de inundação do alto rio Paraná e do Pantanal Sul Matogrossense, Gen. 2 spec. C gen. et spec. nov., Gen. 1 spec. D gen. et spec. nov. e Gen. 2 spec. E gen. et spec. nov. somente do Pantanal Sul Matogrossense e Gen. 1 spec. F gen. et spec. nov. e Gen. 1 spec. G gen. et spec. nov. somente da planície de inundação do rio Amazonas. Todas as novas espécies aqui descritas foram encontradas em populações sexuadas. Em geral, as novas espécies têm uma carapaça curta e suboval, com a valva esquerda sobrepondo a valva direita em todos os lados, com exceção do lado dorsal em algumas espécies. A morfologia do hemipênis e dos palpos preênseis, juntamente com a forma das valvas, foram as mais importantes para distinguir as espécies. A ausência em todas as novas espécies das cerdas curtas que acompanham as cinco cerdas natatórias nas antenas; a presença em todas as novas espécies de uma cerda longa ao lado das duas a-cerdas no primeiro toracópode e a presença/ausência ou comprimento de cerdas específicas no segundo e terceiro toracópodes são características presentes nos apêndices utilizadas para distinção dos novos gêneros e espécies. Discutiu-se a posição taxonômica das sete novas espécies avaliando a validade dos gêneros existentes, especialmente da Keysercypria Karanovic, 2011, e concluiu-se que nossas sete novas espécies representam dois novos gêneros de Cyclocypridinae.
    Description: Masters
    Keywords: Physocypria sensu latu (Crustacea, Ostracoda) ; Candonidae ; Microcrustáceos de água doce ; Taxonomia descritiva ; Morfologia descritiva ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater crustaceans ; ASFA_2015::T::Taxonomy ; ASFA_2015::M::Morphology (animal) ; ASFA_2015::F::Floodplains
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 115pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 5
    facet.materialart.
    Unknown
    O sucesso de uma Poaceae invasora é associado à resiliência à seca, mas não à competição. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-05
    Description: Biological invasions have been occurring at a faster pace as a result of anthropic actions. At the same time, climate change can increase invasion rates, and also favor invading organisms. One of the predictions for climate change is the increase in periods of drought, in some regions of the planet. In this way, environments that suffer from these disorders become more susceptible to invasion by aquatic plants, especially those that are adapted to different types of habitats. Within this context, the objectives were: (i) to determine the response of a native species (Hymenachne pernambucensis) and another invasive species (Urochloa arrecta) to extreme drought, and (ii) to test whether the interspecific competition between them is affected by stress caused by drought. An in situ experiment was carried out, in which the biomass and the length of the species were different for different levels of drought, in which the invasive species was superior to the native species. However, the intensity of relative competition had only different aerial biomass between species, but in this case the invasive species showed a preference for growth in monoculture than in polyculture. It was concluded, then, that the invasive species U. arrecta has greater resilience to droughts than the native species H. pernambucensis. However, the native species showed greater competitive ability. These results may explain the high dominance of this invasive species in the invaded sites, due to its better resistance to disturbances. In the same way, it demonstrates that native species can reduce the invasion rates of this species, considering that it does not grow well in the presence of neighbors.
    Description: Invasões biológicas vêm ocorrendo em um ritmo mais acelerado como resultado de ações antrópicas. Simultaneamente, as mudanças climáticas podem potencializar as taxas de invasão, e ainda favorecer organismos invasores. Uma das previsões para as mudanças climáticas é o aumento dos períodos de seca, em algumas regiões do planeta. Desta forma, ambientes que sofrem esses distúrbios se tornam mais suscetíveis à invasão por plantas aquáticas, em especial por aquelas que estão adaptadas a diversos tipos de habitats. Dentro deste contexto, os objetivos foram de: (i) determinar a resposta de uma espécie nativa (Hymenachne pernambucensis) e outra invasora (Urochloa arrecta) a uma seca extrema, e (ii) testar se a competição interespecífica entre ambas é afetada pelo estresse provocado pela seca. Foi realizado um experimento in situ, no qual a biomassa e o comprimento das espécies foram diferentes para diferentes níveis de seca, em que a espécie invasora foi superior a espécie nativa. Porém, a intensidade de competição relativa teve apenas a biomassa aérea diferente entre as espécies, mas nesse caso a espécie invasora demonstrou preferência por crescimento em monocultura do que em policultura. Concluiu-se, então, que a espécie invasora U. arrecta apresenta maior resiliência a secas do que a espécie nativa H. pernambucensis. Porém, a espécie nativa demonstrou maior habilidade competitiva. Esses resultados podem explicar a alta dominância dessa espécie invasora nos locais invadidos, devido a esta resistir melhor aos distúrbios. De mesmo modo, demonstra que espécies nativas podem reduzir as taxas de invasão dessa espécie, tendo em vista que ela não cresce bem na presença de vizinhos.
    Description: Masters
    Keywords: Poaceae (Gramineae) ; Macrófitas aquáticas invasoras ; Espécies invasoras ; Resiliência ; Mudanças climáticas ; ASFA_2015::M::Macrophytes ; ASFA_2015::A::Aquatic plants ; ASFA_2015::C::Competition ; ASFA_2015::F::Freshwater plants ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::R::Resilience (ecosystem) ; ASFA_2015::C::Climatic changes ; ASFA_2015::A::Alien species
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 32pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 6
    facet.materialart.
    Unknown
    Padrões de diversidade β em ecossistemas aquáticos em diferentes escalas espaciais e temporais. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-30
    Description: Species are heterogeneously distributed and environmental changes, such as the construction of dams or extreme climate events, can modify the dynamics of aquatic organisms. Understanding the processes that drive diversity, across long time periods, can help in the establishment of increasingly accurate conservation measures. This thesis evaluated the patterns of β diversity and metacommunity structure at different spatial and temporal scales in three independent studies in the Upper Paraná river floodplain, Brazil. The first analyzed the seasonal variation of zooplankton β and Elements of Metacommunity Structure [EMS] of zooplankton, over four years (two years of prolonged drought and two years of extreme flooding), and on a smaller (sub-basins) and a larger scale (floodplain). Regardless of the hydrological period and spatial scale, zooplanktonic metacommunity structure remained practically constant throughout the four years, with the predominance of the Clementsian pattern. The predominance of the Clementsian pattern suggests that the associations of zooplankton species in the floodplain responded similarly to the environmental gradient and that the responses differed among species groups. In the second, the taxonomic (LCBD-t) and functional (LCBD-f) ecological uniqueness of zooplankton over 19 years was determined in lakes and lotic systems of two sub-basins (dammed and free-flowing), in addition to investigating which processes (temporal, environmental and biological) drive LCBD-t and LCBD-f. Regardless of the characteristics of each sub-basin, the highest LCBD-t and LCBD-f were related to lower species and trait richness, respectively. The temporal processes were the main drivers of the ecological uniqueness of zooplankton, and they were more important than the biological processes (phytoplankton biovolume and fish biomass, representing food resource and potential predation, respectively). Finally, it was tested whether, in a dammed sub-basin, a prolonged drought makes aquatic metacommunities (phytoplankton, zooplankton, and fish) more similar over time than a period that includes extreme flood events. Only zooplankton underwent homogenization during this period. The β diversity of phytoplankton and fish did not change between different hydrological periods, indicating that the dispersion type (passive or active) does not interfere with drought homogenization. The response between the biological groups was different, reinforcing that the groups are not surrogates of each other. The greater β diversity in the period with extreme floods shows, at least for zooplankton, the importance of the flood pulse, reducing the negative effects of prolonged drought in a dammed sub-basin. The results showed the predominance of a metacommunity pattern resulting from high turnover (Clementsian), indicating that conservation measures should include a greater number of sites, including those with less richness, as they may have a different composition (〉 LCBD). We also emphasize the importance of considering different scales, as each can provide unique insights. It is important that biodiversity studies consider β diversity to understand the mechanisms that drive the metacommunity in the face of environmental changes, especially over longer time scales.
    Description: As espécies estão distribuídas de forma heterogênea e alterações ambientais, como a construção de reservatórios ou eventos climáticos extremos, podem modificar a dinâmica dos organismos aquáticos. Entender os processos que impulsionam a diversidade, em longos períodos de tempo, pode auxiliar no estabelecimento de medidas de conservação cada vez mais precisas. Esta tese avaliou os padrões de diversidade β e estrutura de metacomunidade em diferentes escalas espaciais e temporais em três estudos independentes na planície de inundação do Alto rio Paraná, Brasil. No primeiro foi analisado a variação sazonal da diversidade β e Elementos da Estrutura da Metacomunidade [EMS] do zooplâncton, durante quatro anos (dois anos de seca prolongada e dois anos com inundação extrema), e em uma menor (sub-bacias) e maior escala (planície de inundação). Independente do período hidrológico e da escala, a estrutura da metacomunidade do zooplâncton se manteve praticamente constante ao longo dos quatro anos, com predomínio do padrão Clementsiano. A predominância desse padrão sugere que as associações de espécies responderam de forma semelhante ao gradiente ambiental e que as respostas diferiram entre os grupos de espécies. No segundo foi determinado a singularidade ecológica taxonômica (LCBD-t) e funcional (LCBD-f) do zooplâncton ao longo de 19 anos em lagos e sistemas lóticos de duas sub-bacias (represada e não represada), além de investigar quais processos (temporais, ambientais e biológicos) impulsionam a LCBD-t e LCBD-f. Independentemente das características de cada sub-bacia, os maiores LCBD-t e LCBD-f foram relacionados a menor riqueza de espécies e de traços, respectivamente. Os processos temporais foram os principais impulsionadores da singularidade ecológica do zooplâncton, sendo mais importante do que os processos biológicos (biovolume do fitoplâncton e biomassa dos peixes, representando recurso alimentar e potencial predador, respectivamente). Por último, foi testado se em uma sub-bacia represada, um período de seca prolongada torna as comunidades aquáticas (fitoplâncton, zooplâncton e peixes) mais semelhantes ao longo do tempo do que um período com inundações extremas. Apenas o zooplâncton sofreu homogeneização nesse período. A diversidade β do fitoplâncton e dos peixes não diferiu entre os períodos hidrológicos, indicando que o tipo de dispersão (passivo ou ativo) não interfere na homogeneização da seca. Como a resposta entre os grupos biológicos foi diferente, sugere-se que os grupos não são substitutos uns dos outros. A maior diversidade β no período com inundações extremas mostra, pelo menos para o zooplâncton, a importância do pulso de inundação, reduzindo os efeitos negativos da seca prolongada em uma sub-bacia represada. Os resultados mostraram a predominância de um padrão de metacomunidade resultante de alto turnover (Clementsiano), indicando que medidas de conservação devem incluir um maior número de locais, inclusive aqueles com menor riqueza, uma vez que podem ter composição distinta (〉 LCBD). Reforçamos também a importância de considerar diferentes escalas, uma vez que cada uma pode fornecer insights exclusivos. É importante que estudos de biodiversidade considerem a diversidade β para compreender os mecanismos que impulsionam as metacomunidade diante das alterações ambientais, especialmente em escalas temporais mais longas.
    Description: PhD
    Keywords: Zooplâncton de água doce ; Ecossistemas aquáticos continentais ; Metacomunidades, Ecologia de ; Diversidade-beta ; Traços funcionais ; Escala espaço-temporal ; ASFA_2015::Y::Zooplankton ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::P::Phytoplankton ; ASFA_2015::E::Ecosystem diversity ; ASFA_2015::T::Temporal variations ; ASFA_2015::S::Spatial variations ; ASFA_2015::A::Aquatic environment ; ASFA_2015::F::Floodplains
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 186pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 7
    facet.materialart.
    Unknown
    Neotropical freshwater fishes biogeography: historical and ecological approaches with insights regarding the conservation. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-28
    Description: The patterns and processes that cause a system of regionalization of organisms on the planet are historical and ecological hypotheses that biogeography seeks to elucidate. The Neotropical region is home to one of the greatest richness of freshwater fish in the world that exhibit distinct biogeographic patterns based on ecology, systematics, and evolution. Through methodologies within the scope of historical and/or ecological biogeography, the aims of this study are to present new approaches and contributions to the knowledge of the geographic distribution of freshwater fish in this region, investigating the evolutionary biogeography of Cnesterodontini and Anablepidae, as well as the spatial patterns of ichthyofauna beta-diversity in the Ivaí river basin, Paraná State. The results highlighted well-defined scenarios of the hydrological barriers formation, mainly between coastal basins and drainages that flow into the La Plata River system in South America. These findings enabled congruent relationships of biogeographic areas within the proposals for evolutionary diversification to the Neotropical freshwater fishes. Furthermore, dispersal events caused by headwater captures and sea-level changes satisfactorily complemented the biogeographic patterns and area relationships evidenced for other Neotropical fish lineages, showing similar diversification patterns in the Central Brazil drainages and in the Atlantic coast drainages. The results also showed strong spatial segregation of the ichthyofauna throughout the Ivaí River basin (upper Paraná River system) with emphasis on the mutual influences of niche- and dispersal-based processes. These findings can support new theoretical and methodological references for the main mechanisms and patterns specific to the metacommunities of aquatic organisms. Applying the results herein obtained in historical and ecological consonance has great potential to aid an effective management for the conservation of freshwater fish diversity, whether considering lineages with species at high risk of extinction or even river basins of fundamental importance for maintaining biodiversity and ecosystem functionality in continental aquatic environments.
    Description: Os padrões e processos que ocasionam um sistema de regionalização dos organismos no planeta são hipóteses históricas e ecológicas que a biogeografia busca elucidar. A região Neotropical abriga uma das maiores riquezas de peixes de água doce do mundo, os quais exibem padrões biogeográficos distintos baseados na ecologia, sistemática e evolução. Por intermédio de metodologias dentro do escopo da biogeografia histórica e/ou ecológica, os objetivos deste estudo são apresentar novas abordagens e contribuições ao conhecimento da distribuição geográfica dos peixes de água doce nesta região ao investigar a biogeografia evolutiva de Cnesterodontini e Anablepidae, bem como os padrões espaciais da diversidade beta da ictiofauna na bacia do rio Ivaí, estado do Paraná. Os resultados destacaram cenários bem definidos da formação de barreiras hidrológicas, principalmente entre bacias hidrográficas costeiras e drenagens que fluem para o sistema do rio da Prata na América do Sul. Essas descobertas possibilitaram congruentes relacionamentos de áreas biogeográficas dentro das propostas de diversificação evolutiva à ictiofauna neotropical. Ainda, eventos de dispersão ocasionados por capturas de cabeceiras e mudanças no nível do mar complementaram satisfatoriamente os padrões biogeográficos e os relacionamentos de áreas evidenciados para outras linhagens de peixes neotropicais, apresentando padrões de diversificação semelhantes nas drenagens do Brasil Central e nas drenagens da costa atlântica. Os resultados também evidenciaram forte segregação espacial da ictiofauna ao longo da extensão da bacia do rio Ivaí (sistema do alto rio Paraná), com destaques às influências mútuas de processos baseados em nicho e dispersão. As novas descobertas podem subsidiar referenciais teóricos e metodológicos para os principais mecanismos e padrões específicos às metacomunidades de organismos aquáticos. A aplicação dos resultados aqui obtidos em consonância histórica e ecológica tem grande potencial ao auxílio de um manejo eficaz para a conservação da diversidade de peixes de água doce, seja considerando linhagens com espécies enquadradas em elevado risco de extinção, ou até mesmo bacias hidrográficas de fundamental importância para a manutenção da biodiversidade e funcionalidade ecossistêmica em ambientes aquáticos continentais.
    Description: PhD
    Keywords: Anablepidae (Teleostei: Cyprinodontiformes) "Onesided livebearer" ; Cnesterodontini (Teleostei: Poeciliidae) ; Peixes de água doce de pequeno porte ; Biogeografia cladística e conservação ; Ictiofauna Neotropical ; Metacomunidades aquáticas ; Áreas prioritárias ; Padrões de diversidade beta ; Linhagem marinha ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::B::Biogeography ; ASFA_2015::C::Cladistics ; ASFA_2015::I::Ichthyofauna ; ASFA_2015::C::Conservation
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 161pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 8
    facet.materialart.
    Unknown
    Índice de Sustentabilidade Ecoambiental de sub-bacias hidrográficas (ISE-sb): para a gestão do alto rio Paraná, Brasil. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-28
    Description: The assessment of sustainable development in sub-watersheds plays a central role in rationalizing the decisions taken. A promising form of average indicators of this development is through indicators, and when many are used, they are usually aggregated into indices, which provide a simplified and multidimensional view of the system under analysis. Several sustainability indices for watersheds are proposed in the literature. However, incorporation of extraordinary indicators, that biodiversity, a gap is still a major upgrade. Therefore, the use of biodiversity indicators as representative of the environmental dimension constitutes an advance on the indices presented in the literature recently. The objective was to evaluate the sustainability gradient in the hydrographic basins of the Upper Paraná River, through an eco-environmental sustainability index of hydrographic sub-basins (ISE-sb) that incorporates protected ecological. For this purpose, the indicators selected based on the propositions of Agenda 2030 were identified in four dimensions of sustainability, economic, economic, environmental and thought through a process of sustainability: normal and social. Then, the importance of the indicators was considered, using the multi-criteria analysis based on the Hierarchical Process Analysis (HP) method. The ISE-sb was calculated by means of the weighted media between the sub-indices that represent as dimensions. Finally, we apply the Gi* statistic to identify hotspots and coldspots. The results show that among the dimensions of sustainability, the highest was the one that presented a positive amount of low values. The regions located in the eastern portion, or serra do mar, southern portion, and the Federal District formed sustainability hotspots, while the sub-basins located in the states of Goiás, Mato Grosso do Sul and Minas Gerais formed the sustainability coldposts. A sustainable spatial planning of the hydrographic sub-basins is recommended, adopting cold areas as priorities for sustainability. It highlights the main methodological limitation, a potential reproducibility of the tool in other spaces.
    Description: A avaliação do desenvolvimento sustentável em sub-bacias hidrográficas tem um papel central na racionalização das tomadas de decisões. Uma forma promissora de medir esse desenvolvimento, é por meio de indicadores, e quando muitos indicadores são usados, eles são usualmente agregados em índices, que fornecem uma visão simplificadae multidimensional do sistema em análise. Diversos índices de sustentabilidade para bacias hidrográficas são propostos na literatura. Entretanto, a incorporação de indicadores ecológicos aquáticos, que agreguem aspectos da biodiversidade é, ainda, uma lacuna ainda a ser preenchida. Portanto, a utilização de indicadores de biodiversidade como representantes da dimensão ambiental, se constitui em um avanço aos índices recentemente apresentados na literatura. O objetivo ,foi avaliar o gradiente de sustentabilidade nas bacias hidrográficas do alto rio Paraná, por meio de um índice de sustentabilidade ecoambiental de sub-bacias (ISE-sb) que incorpora indicadores ecológicos aquáticos. Com esse propósito, os indicadores selecionados com base nas proposições da Agenda 2030, foram divididos em quatro dimensões de sustentabilidade: social, econômica, ecoambiental e ambiental negativo, e passaram por um processo de normalização e filtragem. Em seguida, foi ponderada a importância dos indicadores, utilizando-se da análise de multicritério baseada no método Análise de Processos Hierárquicos (AHP).O ISE-sb foi calculado por meio da média ponderada entre os subíndices que representam as dimensões. Por fim aplicamos a estatística espacial Gi* para identificar agrupamentos de hotspots e coldspots. Os resultados mostram que entre as dimensões da sustentabilidade, aquela que apresentou a maior quantidade de valores baixos, foia ambiental positiva. As regiões localizadas na porção leste, ou serra do mar, porção sul, e o Distrito Federal formaram hotspots de sustentabilidade, enquanto que as sub-bacias localizadas nos estados de Goiás, Mato Grosso do Sul e Minas Gerais formaram os coldposts de sustentabilidade. Recomenda-se um planejamento espacial sustentável das sub-bacias hidrográficas, adotando as áreas de coldspots como prioritárias para sustentabilidade. Evidencia a principal limitação metodológica, a potencial reprodutibilidade da ferramenta em outros espaços.
    Description: Masters
    Keywords: Bacias hidrográficas ; Ecologia ; Manejo ; Conservação e preservação ; Sustentabilidade ; Biomonitoramento ; Ictiofauna ; Monitoramento ; Indicadores ambientais ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Conservation ; ASFA_2015::M::Management ; ASFA_2015::S::Sustainability ; ASFA_2015::B::Bioindicators ; ASFA_2015::I::Ichthyofauna ; ASFA_2015::E::Environmental monitoring ; ASFA_2015::R::River basins ; ASFA_2015::H::Hot spots
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 70pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 9
    facet.materialart.
    Unknown
    Impacto do barramento de um rio amazônico nos padrões espaciais e temporais da diversidade beta fitoplanctônica. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-28
    Description: Human activities have caused degradation of aquatic ecosystems and reduced biodiversity. The dams in particular directly impact the spatial and temporal variation of aquatic communities, and especially the phytoplankton community that responds quickly and efficiently to changes in the environment. The impact of a dam in an Amazon river (Jirau Hydroelectric Power Plant) on the spatial and temporal variation of the composition (beta diversity) of phytoplankton was investigated, from October 2009 to July 2017. The hypothesis was tested that the bus modifies beta diversity on a local and regional scale, and alters each location's contribution to beta diversity. The contribution of the sites to the beta diversity was evaluated as a function of the distance from the bus and the environmental heterogeneity. The phytoplankton composition was different between the phases before, fill and after the damming. Biotic homogenization was verified in the tributaries closest to the dam. The more distant sites presented greater contribution to diversity, but were associated with lower values of richness. The dam caused unidirectional changes, locally and regionally, that is, the community moved to a new state over time, and also caused biotic homogenization locally. The impact of the dam was observed only on the tributaries, indicating that run-of-river dams have a greater impact on the tributaries than on the main channel.
    Description: As atividades humanas têm causado degradação dos ecossistemas aquáticos e reduz a biodiversidade. Os barramentos em especial, impactam diretamente a variação espacial e temporal das comunidades aquáticas, e especialmente a comunidade fitoplanctônica que responde de forma rápida e eficiente às mudanças do ambiente. Investigou-se o impacto de um barramento em um rio amazônico (Usina Hidrelétrica de Jirau) sobre a variação espacial e temporal da composição (diversidade beta) do fitoplâncton, no período de outubro de 2009 a julho de 2017. Foi testado a hipótese de que o barramento modifica a diversidade beta em escala local e regional, e altera a contribuição de cada local à diversidade beta. Avaliou-se a contribuição dos locais para a diversidade beta em função da distância do barramento e da heterogeneidade ambiental. A composição fitoplanctônica foi diferente entre as fases antes, enchimento e após o barramento. Verificou-se homogeneização biótica nos tributários mais próximos a barragem. Os locais mais distantes apresentaram maior contribuição a diversidade, mas foram associados a menores valores de riqueza. O barramento causou mudanças unidirecionais, localmente e regionalmente, ou seja, a comunidade passou para um novo estado ao longo do tempo, e também causou homogeneização biótica localmente. Observou-se o impacto do barramento somente nos tributários, indicando que as barragens a fio de água têm maior impacto nos tributários do que no canal principal.
    Description: Masters
    Keywords: Fitoplâncton de água doce ; Barramento ; Impactos antrópicos ; Diversidade beta ; Homogeneização biótica ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::P::Phytoplankton ; ASFA_2015::I::Impacts ; ASFA_2015::B::Biotic environment ; ASFA_2015::R::River basins ; ASFA_2015::E::Environmental impact ; ASFA_2015::R::Reservoirs (water)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 53pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 10
    facet.materialart.
    Unknown
    Warming effects on arctic tundra biogeochemistry are limited but habitat-dependent: a meta-analysis (2022)
    Ecological Society of America
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Pold, G., Baillargeon, N., Lepe, A., Rastetter, E. B., & Sistla, S. A. Warming effects on arctic tundra biogeochemistry are limited but habitat-dependent: a meta-analysis. Ecosphere, 12(10), (2021): e03777, https://doi.org/10.1002/ecs2.3777.
    Description: Arctic tundra consists of diverse habitats that differ in dominant vegetation, soil moisture regimes, and relative importance of organic vs. inorganic nutrient cycling. The Arctic is also the most rapidly warming global area, with winter warming dominating. This warming is expected to have dramatic effects on tundra carbon and nutrient dynamics. We completed a meta-analysis of 166 experimental warming study papers to evaluate the hypotheses that warming changes tundra biogeochemical cycles in a habitat- and seasonally specific manner and that the carbon (C), nitrogen (N), and phosphorus (P) cycles will be differentially accelerated, leading to decoupling of elemental cycles. We found that nutrient availability and plant leaf stoichiometry responses to experimental warming were variable and overall weak, but that both gross primary productivity and the plant C pool tended to increase with growing season warming. The effects of winter warming on C fluxes did not extend into the growing season. Overall, although warming led to more consistent increases in C fluxes compared to N or P fluxes, evidence for decoupling of biogeochemical cycles is weak and any effect appears limited to heath habitats. However, data on many habitats are too sparse to be able to generalize how warming might decouple biogeochemical cycles, and too few year-round warming studies exist to ascertain whether the season under which warming occurs alters how ecosystems respond to warming. Coordinated field campaigns are necessary to more robustly document tundra habitat-specific responses to realistic climate warming scenarios in order to better understand the mechanisms driving this heterogeneity and identify the tundra habitats, communities, and soil pools most susceptible to warming.
    Description: Funding for this project was provided by NSF Signals in the Soil grant number 1841610 to SAS and ER. SAS and ER conceived of and acquired funding for the project. NB completed the literature search.
    Keywords: Arctic ; Biogeochemistry ; Climate change ; Experimental warming ; Meta-analysis ; Stoichiometry ; Tundra
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 11
    facet.materialart.
    Unknown
    Landscape genomics provides evidence of ecotypic adaptation and a barrier to gene flow at treeline for the arctic foundation species Eriophorum vaginatum0 (2022)
    Frontiers Media
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Stunz, E., Fetcher, N., Lavretsky, P., Mohl, J., Tang, J., & Moody, M. Landscape genomics provides evidence of ecotypic adaptation and a barrier to gene flow at treeline for the arctic foundation species Eriophorum vaginatum. Frontiers in Plant Science, 13, (2022): 860439, https://doi.org/10.3389/fpls.2022.860439.
    Description: Global climate change has resulted in geographic range shifts of flora and fauna at a global scale. Extreme environments, like the Arctic, are seeing some of the most pronounced changes. This region covers 14% of the Earth’s land area, and while many arctic species are widespread, understanding ecotypic variation at the genomic level will be important for elucidating how range shifts will affect ecological processes. Tussock cottongrass (Eriophorum vaginatum L.) is a foundation species of the moist acidic tundra, whose potential decline due to competition from shrubs may affect ecosystem stability in the Arctic. We used double-digest Restriction Site-Associated DNA sequencing to identify genomic variation in 273 individuals of E. vaginatum from 17 sites along a latitudinal gradient in north central Alaska. These sites have been part of 30 + years of ecological research and are inclusive of a region that was part of the Beringian refugium. The data analyses included genomic population structure, demographic models, and genotype by environment association. Genome-wide SNP investigation revealed environmentally associated variation and population structure across the sampled range of E. vaginatum, including a genetic break between populations north and south of treeline. This structure is likely the result of subrefugial isolation, contemporary isolation by resistance, and adaptation. Forty-five candidate loci were identified with genotype-environment association (GEA) analyses, with most identified genes related to abiotic stress. Our results support a hypothesis of limited gene flow based on spatial and environmental factors for E. vaginatum, which in combination with life history traits could limit range expansion of southern ecotypes northward as the tundra warms. This has implications for lower competitive attributes of northern plants of this foundation species likely resulting in changes in ecosystem productivity.
    Description: This research was made possible by funding provided by NSF/PLR-1417645 to MM. The Botanical Society of America Graduate Student Research Award and the Dodson Research Grant from the Graduate School of the University of Texas at El Paso provided assistance to ES. The grant 5U54MD007592 from the National Institute on Minority Health and Health Disparities (NIMHD), a component of the National Institutes of Health (NIH) provided bioinformatics resources and support of JM.
    Keywords: Arctic ; Climate change ; Eriophorum vaginatum ; Landscape genomics ; Environmental niche modeling ; Genotype-environment association analyses ; Refugia
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 12
    facet.materialart.
    Unknown
    N and P constrain C in ecosystems under climate change: role of nutrient redistribution, accumulation, and stoichiometry (2022)
    Ecological Society of America
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Rastetter, E., Kwiatkowski, B., Kicklighter, D., Plotkin, A., Genet, H., Nippert, J., O’Keefe, K., Perakis, S., Porder, S., Roley, S., Ruess, R., Thompson, J., Wieder, W., Wilcox, K., & Yanai, R. N and P constrain C in ecosystems under climate change: role of nutrient redistribution, accumulation, and stoichiometry. Ecological Applications, (2022): e2684, https://doi.org/10.1002/eap.2684.
    Description: We use the Multiple Element Limitation (MEL) model to examine responses of 12 ecosystems to elevated carbon dioxide (CO2), warming, and 20% decreases or increases in precipitation. Ecosystems respond synergistically to elevated CO2, warming, and decreased precipitation combined because higher water-use efficiency with elevated CO2 and higher fertility with warming compensate for responses to drought. Response to elevated CO2, warming, and increased precipitation combined is additive. We analyze changes in ecosystem carbon (C) based on four nitrogen (N) and four phosphorus (P) attribution factors: (1) changes in total ecosystem N and P, (2) changes in N and P distribution between vegetation and soil, (3) changes in vegetation C:N and C:P ratios, and (4) changes in soil C:N and C:P ratios. In the combined CO2 and climate change simulations, all ecosystems gain C. The contributions of these four attribution factors to changes in ecosystem C storage varies among ecosystems because of differences in the initial distributions of N and P between vegetation and soil and the openness of the ecosystem N and P cycles. The net transfer of N and P from soil to vegetation dominates the C response of forests. For tundra and grasslands, the C gain is also associated with increased soil C:N and C:P. In ecosystems with symbiotic N fixation, C gains resulted from N accumulation. Because of differences in N versus P cycle openness and the distribution of organic matter between vegetation and soil, changes in the N and P attribution factors do not always parallel one another. Differences among ecosystems in C-nutrient interactions and the amount of woody biomass interact to shape ecosystem C sequestration under simulated global change. We suggest that future studies quantify the openness of the N and P cycles and changes in the distribution of C, N, and P among ecosystem components, which currently limit understanding of nutrient effects on C sequestration and responses to elevated CO2 and climate change.
    Description: This material is based on work supported by the National Science Foundation under Grant No. 1651722 as well through the NSF LTER Program 1637459, 2220863 (ARC), 1637686 (NWT), 1832042 (KBS), 2025849 (KNZ), 1636476 (BNZ), 1637685 (HBR), 1832210 (HFR), 2025755 (AND). We also acknowledge NSF grants 1637653 and 1754126 (INCyTE RCN), and DOE grant DESC0019037. We also acknowledge support through the USDA Forest Service Hubbard Brook Experimental Forest, North Woodstock, New Hampshie (USDA NIFA 2019-67019-29464) and Pacific Northwest Research Station, Corvallis, Oregon.
    Keywords: Carbon dioxide fertilization ; Carbon sequestration ; Carbon-nitrogen interactions ; Carbon-phosphorus interactions ; Climate change ; Long-term ecological research (LTER) ; Nitrogen cycle ; Phosphorus cycle ; Terrestrial ecosystem stoichiometry
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 13
    facet.materialart.
    Unknown
    An investigation of Symbiodiniaceae communities via ITS-2 rDNA amplicon sequencing in Acropora millepora corals from the Great Barrier Reef following exposure to stressors in October 2014 (2022)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Symbiodiniaceae communities in corals with ITS-2 rDNA amplicon sequencing
    Description: Symbiodiniaceae communities were investigated at three locations on the Great Barrier Reef in October 2014. Acropora millepora samples from Davies Reef lagoon (18°30′3.96′′S, 147°22′48′′E), Rib Reef (18°28′53.4′′S, 146°52′24.96′′E), and Pandora Island (18°48′45′′S, 146°25′59.16′′E), were exposed to various stressors including pCO2, heat, bacteria, all of these, or none of these (control). This dataset lists accessions and collection information for ITS-2 rDNA amplicon data that are available at the National Center for Biotechnology Information (NCBI) under BioProject PRJNA596498. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/844431
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1635798
    Keywords: Acropora millepora ; Alpha diversity ; Beta diversity ; Climate change ; Coral ; Symbiodiniaceae
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 14
    facet.materialart.
    Unknown
    Microbiome composition of coral species collected from reefs in Mo'orea, French Polynesia and exposed to various experimental treatments in August 2018 (2022)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Experimental coral treatments
    Description: Coral samples from reefs in Mo'orea, French Polynesia were exposed to various experimental treatments to quantify how different environmental stressors impact the coral health and microbial community structure of the corals. Environmental stressors included increased temperature and nutrients as well as exudate released from corals when they bleach. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/843188
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1635798, NSF Division of Ocean Sciences (NSF OCE) OCE-1635913
    Keywords: Coral reef ; Holobiont ; Coral microbiome ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 15
    facet.materialart.
    Unknown
    Editorial: seagrasses under times of change (2022)
    Frontiers Media
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Winters, G., Teichberg, M., Reuter, H., Viana, I. G., & Willette, D. A. Editorial: seagrasses under times of change. Frontiers in Plant Science, 13, (2022): 870478, https://doi.org/10.3389/fpls.2022.870478.
    Description: Awareness of the ecological importance of seagrasses is growing due to recent attention to their role in carbon sequestration as a potential blue carbon sink (Fourqurean et al., 2012; Bedulli et al.), as well as their role in nutrient cycling (Romero et al., 2006), sediment stabilization (James et al., 2019), pathogen filtration (Lamb et al., 2017), and the formation of essential habitats for economically important marine species (Jackson et al., 2001; Jones et al.). Despite their importance and the increasing public and scientific awareness of seagrasses, simultaneous global (e.g., ocean warming, increase in frequency and severity of extreme events, introduction and spread of invasive species) and local (e.g., physical disturbances, eutrophication, and sedimentation) anthropogenic stressors continue to be the main causes behind the ongoing global decline of seagrass meadows (Orth et al., 2006; Waycott et al., 2009).
    Description: This research was partially funded through the BMBF project SEANARIOS (Seagrass scenarios under thermal and nutrient stress: FKZ 03F0826A) to HR and MT. MT was partially funded through the DFG project SEAMAC (Seagrass and macroalgal community dynamics and performance under environmental change; TE 1046/3-1). IV was supported by a postdoctoral research grant Juan de la Cierva-Incorporación (IJC2019-040554-I) and from MCIN/AEI /10.13039/501100011033 (Spain).
    Keywords: Seagrasses ; Climate change ; Eutrophication ; Responses of seagrasses to single and combined stressors ; Spatial-temporal modeling
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 16
    facet.materialart.
    Unknown
    Relative exposure to microplastics and prey for a pelagic forage fish (2022)
    IOP Publishing
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Chavarry, J. M., Law, K. L., Barton, A. D., Bowlin, N. M., Ohman, M. D., & Choy, C. A. Relative exposure to microplastics and prey for a pelagic forage fish. Environmental Research Letters, 17(6), (2022): 064038, https://doi.org/10.1088/1748-9326/ac7060.
    Description: In the global ocean, more than 380 species are known to ingest microplastics (plastic particles less than 5 mm in size), including mid-trophic forage fishes central to pelagic food webs. Trophic pathways that bioaccumulate microplastics in marine food webs remain unclear. We assess the potential for the trophic transfer of microplastics through forage fishes, which are prey for diverse predators including commercial and protected species. Here, we quantify Northern Anchovy (Engraulis mordax) exposure to microplastics relative to their natural zooplankton prey, across their vertical habitat. Microplastic and zooplankton samples were collected from the California Current Ecosystem in 2006 and 2007. We estimated the abundance of microplastics beyond the sampled size range but within anchovy feeding size ranges using global microplastic size distributions. Depth-integrated microplastics (0–30 m depth) were estimated using a depth decay model, accounting for the effects of wind-driven vertical mixing on buoyant microplastics. In this coastal upwelling biome, the median relative exposure for an anchovy that consumed prey 0.287–5 mm in size was 1 microplastic particle for every 3399 zooplankton individuals. Microplastic exposure varied, peaking within offshore habitats, during the winter, and during the day. Maximum exposure to microplastic particles relative to zooplankton prey was higher for juvenile (1:23) than adult (1:33) anchovy due to growth-associated differences in anchovy feeding. Overall, microplastic particles constituted fewer than 5% of prey-sized items available to anchovy. Microplastic exposure is likely to increase for forage fishes in the global ocean alongside declines in primary productivity, and with increased water column stratification and microplastic pollution.
    Description: This work originated from the Plastic Awareness Global Initiative (PAGI) international workshop, hosted by the Center for Marine Biodiversity and Conservation (CMBC) at Scripps Institution of Oceanography at the University of California San Diego in 2018, with support from Igor Korneitchouk and the Wilsdorf Mettler Future Foundation. We thank the workshop participants for early discussions and a collaborative meeting space. We thank Kelly Lance for her illustration contributions, and the SIO Communications Office for their support. We thank Miriam Doyle and Ryan Rykaczewski for their assistance in data acquisition, and we thank Penny Dockry and Stuart Sandin of CMBC for administrative and logistical support. Julia Chavarry was supported by the San Diego Fellowship. This paper is a contribution from the California Current Ecosystem Long Term Ecological Research site, supported by the National Science Foundation.
    Keywords: Upwelling ecosystems ; Food webs ; Climate change ; Engraulis mordax
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 17
    facet.materialart.
    Unknown
    Guiding biological control of alligator weed by Agasicles hygrophila (Coleoptera: Chrysomelidae) at macroscale: where are the potential global areas suitable to apply it and how it can change in climate change scenarios. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-06
    Description: Invasive species can have many negative impacts on the biodiversity, ecosystem services, human health and the economy, and therefore need to be managed. An amphibious weed of global importance, Alternanthera philoxeroides, and the macroecological patterns of its biological control were evaluated using one of its main specialist herbivores, Agasicles hygrophila. This was considered the first successful case of biological control of an aquatic plant, although it is not equally effective on a global scale. Due to their different environmental tolerances and the greater phenotypic plasticity of the plant, the distribution of both species do not always overlap in the globe, creating geographic variability in the efficiency of biocontrol. The first approach was to analyze the current global potential distribution of A. philoxeroides and A. hygrophila to seek the areas of overlaps and gaps between them. The overlapping areas would be the most relevant for using A. hygrophila as alligator weed biological control in the globe. However, in response of climate change, it seems that the alligator weed is worryingly spreading across the globe, which can worsen in future scenarios and alter its distribution in the next decades. The second approach evaluated the effects of climate change on the global distribution of A. philoxeroides and A. hygrophila. New distribution areas for both species in future global warming scenarios and new overlapping and non-overlapping areas across the globe were identified. Species Distribution Models (SDMs) were applied in both chapters to predict the potential distribution of the two species in present and future scenarios considering different environmental predictors in each one. Currently, the southeast coast of the USA, southeast China and New South Wales, Australia are the most favorable areas in the world to apply alligator weed biocontrol, while the west coast and mid-latitudes in the east of the USA and the eastern Australia are not favorable. The results were corroborated by reports in the literature that demonstrated successful control in overlapping areas and failures in non-overlapping areas of the models’ distributions. However, while general geographic patterns will hold in future scenarios, it is predicted a major northward expansion of the alligator weed, but not of the insect, especially in the USA, Canada, Europe, China, South Korea and Japan, which will create a new zone of low or no control efficiency at higher latitudes. These macroecological patterns will help direct efforts to apply the biological control for the alligator weed not only today, but also in future climate change scenarios.
    Description: Espécies invasoras podem causar muitos impactos negativos na biodiversidade, nos serviços ecossistêmicos, na saúde humana e na economia e, portanto, precisam ser manejadas. Avaliou-se uma erva daninha anfíbia de importância global, Alternanthera philoxeroides, e nos padrões macroecológicos de seu controle biológico usando um de seus principais herbívoros especialistas, Agasicles hygrophila. Este foi considerado o primeiro caso bem sucedido de controle biológico de uma macrófita, embora não seja igualmente eficaz em escala global. Devido às suas diferentes tolerâncias ambientais e à maior plasticidade fenotípica da planta, a distribuição de ambas as espécies nem sempre se sobrepõe no globo, criando variabilidade geográfica na eficiência do biocontrole. O primeiro enfoque foi analisar a distribuição potencial global atual de A. philoxeroides e A. hygrophila para buscar as áreas de sobreposição e não sobreposição entre elas. As áreas sobrepostas seriam as mais relevantes para o uso de A. hygrophila como controle biológico da erva-de-jacaré no globo. Entretanto, em resposta às mudanças climáticas, a erva-de-jacaré está se expandindo de forma preocupante pelo globo, o que pode agravar em cenários futuros e alterar sua distribuição nas próximas décadas. O segundo enfoque avaliou-se os efeitos das mudanças climáticas na distribuição global de A. philoxeroides e A. hygrophila. Identificou-se as novas áreas de distribuição para ambas as espécies em cenários futuros de aquecimento global e as novas áreas sobrepostas e não sobrepostas em todo o globo. Modelos de Distribuição de Espécies (MDEs) foram aplicados em ambas as abordagens para predizer a distribuição potencial das duas espécies em cenários presentes e futuros considerando diferentes preditores ambientais em cada um. Atualmente, a costa sudeste dos EUA, sudeste da China e Sidnei, Austrália, são as áreas mais favoráveis no mundo para aplicar o biocontrole da erva-de-jacaré, enquanto a costa oeste e latitudes médias no leste dos EUA e no leste da Austrália não são favoráveis. Os resultados foram corroborados por relatos na literatura que demonstraram controle bem-sucedido em áreas sobrepostas e mal-sucedido em áreas não sobrepostas das distribuições dos modelos. Entretanto, embora os padrões geográficos gerais se mantenham em cenários futuros, é prevista uma grande expansão da erva-de-jacaré, mas não do inseto, para o norte, especialmente nos EUA, Canadá, Europa, China, Coreia do Sul e Japão, o que criará uma nova zona de baixa ou nenhuma eficiência de controle em latitudes mais altas. Esses padrões macroecológicos ajudarão a direcionar os esforços para aplicar o controle biológico da erva-de-jacaré não apenas atualmente, mas também em cenários futuros de mudanças climáticas.
    Description: PhD
    Keywords: Alternanthera philoxeroides (Mart.) Griseb. (Amaranthaceae) “erva-de-jacaré” ; Plantas aquáticas invasoras ; Macrófitas aquáticas de água doce ; Insetos especialistas ; Herbivoria ; Controle biológico ; Mudanças climáticas ; Macroecologia ; ASFA_2015::A::Aquatic plants ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Alien species ; ASFA_2015::M::Macrophytes ; ASFA_2015::A::Aquatic insects ; ASFA_2015::B::Biological control ; ASFA_2015::I::Insects (aquatic) ; ASFA_2015::C::Climatic changes ; ASFA_2015::H::Herbivores
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 76pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 18
    facet.materialart.
    Unknown
    Padrões de diversidade beta de macroinvertebrados bentônicos frente ao gradiente de recuperação ambiental em riachos temperados acidificados. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-11
    Description: The industrial advance of Europe between the 19th and 20th centuries resulted in major environmental impacts. Among these impacts, the deposition of acid compounds through acid rain stands out, and this phenomenon led to the acidification of water bodies. However, from the 1980s on, with the application of stricter environmental regulations, a gradual recovery of abiotic parameters began, including pH values, which began to return to less acidic ranges. Thus, we investigated the responses of the benthic community to the gradual recovery of abiotic variables after years of intense acidification, analyzing changes in community structure and, specifically, variations in beta diversity. The study was developed with data from streams in Wales, collected and provided by two research projects that monitor the region's water bodies. The streams were classified according to abiotic characteristics and the surrounding vegetation (Acid Forest, Acid Moorland and Circumneutral Moorland). In the first approach, the community of 69 streams was analyzed, testing whether (i) the composition of macroinvertebrate communities differed among the types of environments and years analyzed; and whether (ii) in early years beta diversity among streams was lower than in more recent years, as well as in streams of a more acidic category. Samples were collected in 1984, 1995, and 2012, with the earliest year under the greatest influence of acidification. A segregation in macroinvertebrate composition was observed between 1984 and the other years, and this difference in community composition between the years suggests that environmental recovery with rising pH values, allowed the entry and establishment of new macroinvertebrate species in the streams. The lowest beta diversity value was also observed in 1984, indicating biotic homogenization in this period and an increase in community dissimilarity over time. In the second approach, we investigated the hypothesis that a gradual increase in temporal beta diversity (TBI) values occurs over time. This was done by sampling eight streams in Wales over the period 1985 to 2018, and comparing beta diversity between the reference year 1985 with all other years. There was an increase in TBI values over the years for all environments, showing evidence of biological recovery concomitant with restoration of abiotic values. The results contributed to the understanding that the biotic community also responds to environmental recovery, and there are different ways to evaluate this process, such as beta diversity. The importance of long-term research is emphasized so that such changes can be monitored.
    Description: O avanço industrial da Europa entre os séculos XIX e XX resultou em grandes impactos ambientais. Dentre esses impactos, destaca-se a deposição de compostos ácidos através da chuva ácida, e tal fenômeno levou à acidificação de corpos d’água. Contudo, a partir da década de 1980, com a aplicação de normas ambientais mais rígidas, teve início uma recuperação gradual dos parâmetros abióticos, incluindo os valores de pH, que começaram a retornar para faixas menos ácidas. Investigou-se as respostas da comunidade bentônica diante da recuperação gradual das variáveis abióticas após anos de intensa acidificação, analisando mudanças na estrutura da comunidade e, especificamente, as variações da diversidade beta. Os estudos foram desenvolvidos com dados de riachos do País de Gales, coletados e cedidos por dois projetos de pesquisas galeses que monitoram os corpos aquáticos da região, sendo os riachos classificados de acordo com as características abióticas e da vegetação do entorno (Acid Forest, Acid Moorland e Circumneutral Moorland). Na primeira abordagem, analisou-se a comunidade de 69 riachos, testando se (i) a composição das comunidades difere entre os tipos de ambientes e anos analisados; e se (ii) nos anos iniciais a diversidade beta entre os riachos foi menor do que nos anos mais recentes, assim como nos riachos de uma categoria mais ácida. As amostras foram coletadas em 1984, 1995 e 2012, sendo o ano mais antigo sob maior influência da acidificação. Observou-se uma segregação na composição da biota entre 1984 e os demais anos, e essa diferença na composição da comunidade entre os anos sugere que a recuperação ambiental com ascensão nos valores de pH, permitiu a entrada e estabelecimento de novas espécies de macroinvertebrados nos riachos. O menor valor de diversidade beta também foi observado em 1984, indicando homogeneização biótica neste período e aumento da dissimilaridade das comunidades com o tempo. Na segunda abordagem, investigou-se a hipótese de que ocorre um aumento gradativo nos valores de diversidade beta temporal (TBI) ao longo do tempo. Para tanto, foram amostrados oito riachos no País de Gales no período entre 1985 e 2018, e comparado a diversidade beta dos riachos entre o ano referência 1985 com todos os demais anos. Houve um aumento dos valores de TBI ao longo dos anos para todos ambientes, mostrando indícios de recuperação biológica concomitante com o restabelecimento dos valores abióticos. Os resultados contribuíram para o entendimento de que a comunidade biótica também responde à recuperação ambiental. Sendo a diversidade beta uma das formas de se avaliar tal processo. E ressalta-se a importância de pesquisas de longa duração para que tais respostas bióticas possam ser monitoradas.
    Description: PhD
    Keywords: Macroinvertebrados bentônicos de água doce ; Diversidade beta ; Recuperação ambiental ; Acidificação ambiental ; Chuva ácida ; Riachos ; Riachos acidificados ; ASFA_2015::M::Macrobenthos ; ASFA_2015::A::Acid rain ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::S::Streams ; ASFA_2015::A::Acidification ; ASFA_2015::S::Stream ecology
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 55pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 19
    facet.materialart.
    Unknown
    Aquatic macrophytes as drivers of multiple aspects of fish community: trophic, functional and taxonomic fish responses in tropical and temperate freshwater ecosystems. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-12
    Description: Macrophytes are widely recognized for increasing habitat complexity and driving a relevant role in structuring communities in aquatic ecosystems. We investigated how the density, coverage and diversity of macrophytes can influence multiple aspects of fish community, including functional alpha and beta diversity, foraging efficiency, trophic niche breadth and overlap, total abundance and biomass of fish, as well as of certain species and sizes of fish. We used 30 macrophyte stands sampled in the littoral zone of a tropical river, as well as a dataset of 88 shallow temperate lakes. In the latter case, two spatial scales were considered (lake and points within a lake), since there is usually a negative relationship between fish and macrophyte coverage, and this relationship may be more evident at the point scale, while the effect is attenuated at the lake scale. The results showed that macrophytes can select functional characteristics of fish communities and influence their alpha and beta functional diversity. The highest values of functional alpha diversity occurred in intermediate macrophyte density and high macrophyte diversity. The variation in macrophyte density was strongly responsible for variations in functional beta diversity. Fish showed general trophic responses to the variation in macrophyte attributes, but these responses also depended on fish feeding habits, with herbivores niche breadth responding in the opposite way to omnivores. The increase in macrophyte density led to an increase in fish consumption of higher plants and foraging efficiency, and reduced trophic niche breadth. Fish niche overlap was higher at intermediate levels of macrophyte density. Fish responses depended on fish species identity, lake productivity and water depth. The deeper and more eutrophic the lakes, the more fish tended to occupy macrophyte-covered points within a lake. The results emphasize how aquatic plants can affect the fish community by influencing swimming, food availability and interactions between species, and that the relationship between fish and macrophytes can vary according to the scale of the study and the fish characteristics. The application of the results obtained here has great potential to help in projects of management and conservation of biodiversity, and in the choice of the best configurations of macrophyte stands for the maintenance of ichthyofauna.
    Description: As macrófitas são amplamente reconhecidas por aumentarem a complexidade do habitat e exercerem papel relevante na estruturação das comunidades em ecossistemas aquáticos. Investigou-se como a densidade, cobertura e diversidade de macrófitas podem influenciar múltiplos aspectos da comunidade de peixes, incluindo diversidade alfa e beta funcional, eficiência de forrageamento, amplitude e sobreposição de nicho trófico, abundância e biomassa de total de peixes, bem como de determinadas espécies e tamanhos de peixes. Utilizou-se 30 bancos de macrófitas amostrados na zona litorânea de um rio tropical, bem como, um conjunto de dados de 88 lagos rasos temperados. Neste ultimo caso, foram consideradas duas escalas espaciais (lago e pontos dentro do lago), visto que geralmente há uma relação negativa entre peixes e a cobertura de macrófitas, e essa relação pode ser mais evidente na escala de ponto dentro do lago, enquanto o efeito é atenuado na escala de lago. Os resultados evidenciaram que as macrófitas podem selecionar características funcionais das comunidades de peixes e influenciar sua diversidade funcional alfa e beta. Os maiores valores de diversidade alfa funcional ocorreram em densidades intermediárias e elevada diversidade de macrófitas. A variação na densidade de macrófitas foi fortemente responsável pelas variações na diversidade beta funcional. Os peixes apresentaram respostas tróficas gerais à variação dos atributos das macrófitas, mas estas respostas também dependeram dos hábitos alimentares dos peixes, com a amplitude de nicho dos herbívoros respondendo de forma oposta à amplitude de onívoros. O aumento na densidade de macrófitas levou a um aumento no consumo de vegetais superiores pelos peixes e na eficiência de forrageamento, e reduziu a amplitude do nicho trófico. A sobreposição de nicho de peixes foi maior nos níveis intermediários de densidade de macrófitas. As respostas dos peixes dependeram da identidade da espécie de peixe, produtividade da lagoa e profundidade da água. Quanto mais profundos e eutróficos eram os lagos, mais os peixes tenderam a ocupar pontos cobertos por macrófitas dentro de um lago. Mediante os resultados, ressaltamos como as plantas aquáticas podem afetar a comunidade de peixes por influenciarem na natação, disponibilidade de alimento e interações entre as espécies, e que a relação entre peixe e macrófita pode variar de acordo com a escala do estudo e as características dos peixes considerados. A aplicação dos resultados aqui obtidos tem grande potencial de auxílio em projetos de manejo e conservação da biodiversidade, e na escolha das melhores configurações de bancos de macrófitas para a manutenção da ictiofauna.
    Description: PhD
    Keywords: Peixes de água doce ; Macrófitas aquáticas submersas ; Comunidades, Ecologia de ; Diversidade funcional e taxonômica ; Diversidade taxonômica ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Floodplains ; ASFA_2015::A::Assemblages ; ASFA_2015::T::Trophic levels ; ASFA_2015::E::Ecosystems
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 153pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 20
    facet.materialart.
    Unknown
    Sporadic P limitation constrains microbial growth and facilitates SOM accumulation in the stoichiometrically coupled, acclimating microbe-plant-soil model (2022)
    Elsevier
    Details
    Publication Date: 2022-10-18
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Pold, G., Kwiatkowski, B. L., Rastetter, E. B., & Sistla, S. A. Sporadic P limitation constrains microbial growth and facilitates SOM accumulation in the stoichiometrically coupled, acclimating microbe-plant-soil model. Soil Biology & Biochemistry, 165, (2022): 108489, https://doi.org/10.1016/j.soilbio.2021.108489.
    Description: Requirements for biomass carbon (C), nitrogen (N), and phosphorus (P) constrain organism growth and are important agents for structuring ecosystems. Arctic tundra habitats are strongly nutrient limited as decomposition and recycling of nutrients are slowed by low temperature. Modeling interactions among these elemental cycles affords an opportunity to explore how disturbances such as climate change might differentially affect these nutrient cycles. Here we introduce a C–N–P-coupled version of the Stoichiometrically Coupled Acclimating Microbe-Plant-Soil (SCAMPS) model, “SCAMPS-CNP”, and a corresponding modified CN-only model, “SCAMPS-CN”. We compared how SCAMPS-CNP and the modified SCAMPS-CN models project a moderate (RCP 6.0) air warming scenario will impact tussock tundra nutrient availability and ecosystem C stocks. SCAMPS-CNP was characterized by larger SOM and smaller organism C stocks compared to SCAMPS-CN, and a greater reduction in ecosystem C stocks under warming. This difference can largely be attributed to a smaller microbial biomass in the CNP model, which, instead of being driven by direct costs of P acquisition, was driven by variable resource limitation due to asynchronous C, N, and P availability and demand. Warming facilitated a greater relative increase in plant and microbial biomass in SCAMPS-CNP, however, facilitated by increased extracellular enzyme pools and activity, which more than offset the metabolic costs associated with their production. Although the microbial community was able to flexibly adapt its stoichiometry and become more bacteria-like (N-rich) in both models, its stoichiometry deviated further from its target value in the CNP model because of the need to balance cellular NP ratio. Our results indicate that seasonality and asynchrony in resources affect predicted changes in ecosystem C storage under warming in these models, and therefore build on a growing body of literature indicating stoichiometry should be considered in carbon cycling projections.
    Description: This work was funded by the National Science Foundation Signals in the Soil grant number 1841610 to SAS and EBR.
    Keywords: Stoichiometry ; Modeling ; Microbial physiology ; Tundra ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 21
    facet.materialart.
    Unknown
    Effects of ocean acidification on the performance and interaction of fleshy macroalgae and a grazing sea urchin (2022)
    Elsevier
    Details
    Publication Date: 2022-05-27
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Burnham, K. A., Nowicki, R. J., Hall, E. R., Pi, J., & Page, H. N. Effects of ocean acidification on the performance and interaction of fleshy macroalgae and a grazing sea urchin. Journal of Experimental Marine Biology and Ecology, 547, (2022): 151662, https://doi.org/10.1016/j.jembe.2021.151662.
    Description: When predicting the response of marine ecosystems to climate change, it is increasingly recognized that understanding the indirect effects of ocean acidification on trophic interactions is as important as studying direct effects on organism physiology. Furthermore, comprehensive studies that examine these effects simultaneously are needed to identify and link the underlying mechanisms driving changes in species interactions. Using an onshore ocean acidification simulator system, we investigated the direct and indirect effects of elevated seawater pCO2 on the physiology and trophic interaction of fleshy macroalgae and the grazing sea urchin Lytechinus variegatus. Macroalgal (Dictyota spp.) biomass increased despite decreased photosynthetic rates after two-week exposure to elevated pCO2. Algal tissue carbon content remained constant, suggesting the use of alternative carbon acquisition pathways beneficial to growth under acidification. Higher C:N ratios driven by a slight reduction in N content in algae exposed to elevated pCO2 suggest a decrease in nutritional content under acidification. Urchin (L. variegatus) respiration, biomass, and righting time did not change significantly after six-week exposure to elevated pCO2, indicating that physiological stress and changes in metabolism are not mechanisms through which the trophic interaction was impacted. Correspondingly, urchin consumption rates of untreated macroalgae (Caulerpa racemosa) were not significantly affected by pCO2. In contrast, exposure of urchins to elevated pCO2 significantly reduced the number of correct foraging choices for ambient macroalgae (Dictyota spp.), indicating impairment of urchin chemical sensing under acidification. However, exposure of algae to elevated pCO2 returned the number of correct foraging choices in similarly exposed urchins to ambient levels, suggesting alongside higher C:N ratios that algal nutritional content was altered in a way detectable by the urchins under acidification. These results highlight the importance of studying the indirect effects of acidification on trophic interactions simultaneously with direct effects on physiology. Together, these results suggest that changes to urchin chemical sensing and algal nutritional quality are the driving mechanisms behind surprisingly unaltered urchin foraging behavior for fleshy macroalgae under joint exposure to ocean acidification. Consistent foraging behavior and consumption rates suggest that the trophic interaction between L. variegatus and fleshy macroalgae may be sustained under future acidification. However, increases in fleshy macroalgal biomass driven by opportunistic carbon acquisition strategies have the potential to cause ecological change, depending on how grazer populations respond. Additional field research is needed to determine the outcome of these results over time and under a wider range of environmental conditions.
    Description: This work was supported by Mote Marine Laboratory Postdoctoral Fellowships (RJN and HNP), Becker Internship Funding, and philanthropic funds to ERH.
    Keywords: Climate change ; Elevated pCO2 ; Direct effects ; Physiology ; Indirect effects ; Herbivory
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 22
    facet.materialart.
    Unknown
    Caracterização molecular de digenéticos parasitas de gastrópodes (Mollusca) do baixo rio Ivaí, Paraná, Brasil. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-05
    Description: Thiarids are pantropical gastropods endemic to South America and are found in lentic and lotic freshwater environments. These gastropods act as intermediate hosts for several species of digeneans. However, it is important to consider that there are difficulties for a correct identification of these digeneans in certain stages of the life cycle since the larvae have a reduced size and few morphological characteristics for diagnosis. In this way, techniques based on molecular markers become an extremely important tool, combining the use of ribosomal and mitochondrial regions. Considering that there are no records in the literature of studies involving parasites and gastropods as intermediate hosts in the Ivaí River, this study is the first regarding these relationships. Seventy-six specimens of gastropods were collected. Of these, 21 were parasitized. As for the parasites, 16 different morphotypes were found. The gastropod DNA was amplified using the COI marker. The gastropods showed genetic similarity with Aylacostoma chloroticum with different percentages of identity. As for the parasites, COI and 28S markers were used for DNA amplification. Four different taxa were characterized with both markers. With the mitochondrial marker it was possible to confirm only one genus among the digeneans found. However, the 28S ribosomal marker proved to be more effective for the identification of Ivaí River parasites, showing higher similarity values in relation to sequences available in the databases and lower values of genetic distance. In this way, it was possible to confirm the classification of the morphotypes into two distinct genera.
    Description: Os tiarídeos são gastrópodes pantropicais endêmicos da América do Sul e são encontrados em ambientes de água doce lênticos e lóticos. Esses gastrópodes atuam como hospedeiros intermediários de várias espécies de digenéticos. No entanto, é importante considerar que existem dificuldades para uma identificação correta desses digenéticos em determinadas fases do ciclo de vida, visto que as larvas possuem um tamanho reduzido e poucas características morfológicas para diagnóstico. Dessa maneira, técnicas baseadas em marcadores moleculares tornam-se uma ferramenta de extrema importância, combinando a utilização de regiões ribossômicas e mitocondriais. Considerando que não há registros na literatura de estudos envolvendo parasitas e gastrópodes como hospedeiros intermediários no rio Ivaí, este estudo é o primeiro a respeito dessas relações. Foram coletados 76 espécimes de gastrópodes. Desses, 21 encontravam-se parasitados. Quanto aos parasitas, foram encontrados 16 morfotipos distintos. O DNA dos gastrópodes foi amplificado utilizando o marcador COI. Os gastrópodes apresentaram similaridade genética com Aylacostoma chloroticum com diferentes percentuais de identidade. Quanto aos parasitas, para amplificação do DNA foram utilizados os marcadores COI e 28S. Quatro taxa diferentes foram caracterizados com ambos os marcadores. Com o marcador mitocondrial foi possível confirmar apenas um gênero dentre os digenéticos encontrados. Todavia, o marcador ribossômico 28S se mostrou mais eficaz para a identificação dos parasitas do rio Ivaí, apresentando maiores valores de similaridade em relação a sequências disponíveis nos bancos de dados e menores valores de distância genética. Dessa maneira, foi possível confirmar a classificação dos morfotipos em dois gêneros distintos.
    Description: Masters
    Keywords: Digenea (Trematoda: Platyhelminthes) “digenéticos” ; Gastrópodes (Mollusca) ; Genética molecular ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Mollusks (freshwater) ; ASFA_2015::P::Parasites ; ASFA_2015::M::Molluscs (freshwater) ; ASFA_2015::M::Molecular biology
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 51pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 23
    facet.materialart.
    Unknown
    Filogeografia como escopo para explorar a invasão em Ludwigia (Onagraceae) de ambientes não nativos. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-05
    Description: Ludwigia has some invasive macrophyte species that have not yet been explored under the scope of phylogeography, a promising area to understand the ecology of invasions using barcode molecular markers sensitive to intraspecific variations. Thus, it was theorized that barcode markers used in invasive species of Ludwigia occurring in non-native regions would be phylogeographically informative. Sequences of the molecular markers trnH-psbA, rbcL, matK and phyC from invasive populations of L. peploides and L. grandiflora were used as they are the only ones available in Genbank. A gene tree was generated by the Neighborn-Joining method and a haplotypic network by the Median-Joining method for each species. The trnH-psbA marker was the only phylogeographically informative marker for detecting intraspecific variations in the analyzed taxa. Three haplotypes were detected for L. grandiflora and two haplotypes for L. peploides. Three geographically distinct founder populations of L. grandiflora were introduced in Europe, with Hg1 shared with the US population, while L. peploides has a founder population in Europe and another in the US. The long history of the introduction of these species in Europe and the limited geographic scope of molecular sampling demonstrate that these data are underestimated. A search in the Web of Science database exposed a paucity of molecular data for invasive species of Ludwigia, highlighting the contribution of the results to the information on these haplotypic relationships in the context of invasive biology. Therefore, the detection of haplotypic diversity of invasive species of Ludwigia proved to be promising when investigated by the phylogeographic scope, supporting a better understanding of the management and ecology of these haplotypes in non-native areas.
    Description: Ludwigia possui algumas espécies de macrófitas invasoras que ainda não foram exploradas sob o escopo da filogeografia, uma promissora área para compreender a ecologia das invasões utilizando marcadores moleculares barcode sensíveis a variações intraespecíficas. Assim, testou-se quais marcadores barcode utilizados em espécies invasoras de Ludwigia ocorrentes em regiões não nativas seriam filogeograficamente informativos. Utilizou-se sequências dos marcadores moleculares trnH-psbA, rbcL, matKe phyC de populações invasoras de L. peploides e L. grandiflora por serem as únicas disponíveis no Genbank. Gerou-se uma árvore gênica pelo método Neighborn-Joining e uma rede haplotípica pelo método Median-Joining para cada espécie. O marcador trnH-psbA foi o único informativo filogeograficamente por detectar variações intraespecíficas nos táxons analisados. Detectou-se três haplótipos para L. grandiflorae dois haplótipos para L. peploides. Três populações fundadoras geograficamente distintas de L. grandiflora foram introduzidas na Europa, sendo Hg1 compartilhado com a população estadunidense, enquanto L. peploidespossui uma população fundadora na Europa e outra nos EUA. O antigo histórico de introdução dessas espécies na Europa e a abrangência geográfica limitada da amostragem molecular demonstram que esses dados estão subestimados. Uma pesquisa feita na base de dados Web of Science expôs uma escassez de dados moleculares para espécies invasoras de Ludwigia, ressaltando a contribuição dos resultados quanto as informações sobre essas relações haplotípica no contexto da biologia das invasões. Portanto, a detecção da diversidade haplotípica de espécies invasoras de Ludwigia mostrou-se promissora quando investigada pelo escopo filogeográfico, subsidiando o melhor entendimento sobre o manejo e a ecologia desses haplótipos em áreas não nativas.
    Description: Masters
    Keywords: Ludwigia (Onagraceae) “cruz-de-malta” ; Macrófitas aquáticas invasoras ; Filogeografia ; Biogeografia ; Marcadores moleculares ; Manejo ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::B::Biogeography ; ASFA_2015::A::Alien species ; ASFA_2015::M::Molecular biology ; ASFA_2015::M::Molecular structure
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 29pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 24
    facet.materialart.
    Unknown
    DNA barcoding de Platanichthys platana (Regan, 1917) (Clupeiformes, Clupeidae) de diferentes bacias hidrográficas. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-05
    Description: South America has fish endemic to continental fresh waters, but derived from clades predominantly and ancestrally distributed in marine environments, such as Platanichthys platana. This species is considered the smallest sardine of the Clupeidae with its type locality in the La Plata river. In 2007, there were the first records of P. platana in the upper Paraná river basin and in 2012 in the upper Paraná river floodplain. The variation in the length of specimens from this basin generated curiosity about their identity and origin of introduction. Sequences from the COI region of the specimens were used for genetic distance calculations, construction of gene trees and haplotype networks. The results obtained indicate that all analyzed specimens belong to P. platana. Eight haplotypes were found, some exclusive to the coastal basins of Santa Catarina, Rio Grande do Sul and Negro river basin. The basins of the La Plata river, the Lago and the upper Paraná river floodplain shared different haplotypes. The phylogeographic pattern presented in this study can be justified by the presence of populations of P. platana in the same paleoarea, before the geological process that configured the current architectures of the observed basins, by vicariance. During the Mesozoic and Cenozoic several vicarious events occurred between the coastal watersheds of Brazil that can be attributed to marine regressions and transgressions by continental lands. It is also assumed that specimens from the upper Paraná river floodplain were introduced to the region from Argentine regions.
    Description: A América do Sul apresenta peixes endêmicos de águas doces continentais, mas derivados de clados predominantemente e ancestralmente distribuídos em ambientes marinhos, como Platanichthys platana. Essa espécie é considerada a sardinha de menor tamanho de Clupeidae com sua localidade-tipo no rio de La Plata. Em 2007, houve os primeiros registros de P. platana na bacia do alto rio Paraná e em 2012 na planície de inundação do alto rio Paraná. A variação do comprimento dos espécimes dessa bacia gerou curiosidade sobre sua identidade e origem de introdução. Sequências da região COI dos espécimes foram e utilizadas para cálculos de distância genética, construção de árvores gênicas e rede de haplótipos. Os resultados obtidos indicam que todos os exemplares analisados pertencem a P. platana. Oito haplótipos foram encontrados, alguns exclusivos dos exemplares das bacias litorâneas de Santa Catarina, do Rio Grande do Sul e bacia do rio Negro. As bacias do rio de La Plata, do Lago e da planície de inundação do alto rio Paraná compartilharam diferentes haplótipos. O padrão filogeográfico apresentado nesse estudo pode ser justificado pela presença de populações de P. platana em uma mesma paleoarea, antes do processo geológico que configurou as atuais arquiteturas das bacias observadas, pela vicariância. Durante o Mesozóico e Cenozóico vários eventos vicariantes ocorreram entre as bacias hidrográficas costeiras do Brasil que podem ser atribuídos às regressões e transgressões marinhas por terras continentais. Pressupõe-se também que os espécimes da planície de inundação do alto rio Paraná tenham sido introduzidos na região a partir de regiões argentinas.
    Description: Masters
    Keywords: Platanichthys platana (Regan, 1917) (Clupeiformes, Clupeidae) “sardinha” ; Biogeografia ; Genética molecular ; Diversidade genética ; Bacias hidrográficas ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::B::Biogeography ; ASFA_2015::G::Genetic diversity ; ASFA_2015::R::River basins ; ASFA_2015::R::Reservoirs (water)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 36pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 25
    facet.materialart.
    Unknown
    Alteração da concentração de nutrientes causada por P. ambrosettii afeta relação entre macrófita invasora H. verticillata e nativa E. najas: uma abordagem experimental. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-10-05
    Description: Non native species can negatively affect the invaded environment. Often, these species have biological characteristics that benefit other non natives and facilitate their invasion, so knowing the facilitation mechanisms between invaders are useful to mitigate their damage to the ecosystem. Thus, in this study we tested the hypothesis that Pterygoplichthys ambrosettii, a non native catfish, has habits that can alter nutrient concentrations (phosphorus and nitrogen) in the water column, and positively affect the growth of an invasive macrophyte species in detriment of a native one, characterizing ecological facilitation among invasive species. Therefore, an experiment was conducted with six treatments and four replicas, using the invasive macrophyte Hydrilla verticillata and the native Egeria najas, in the presence and absence of P. ambrosettii, all with occurrence recorded in the upper Paraná River floodplain. The results showed that the treatments with P. ambrosettii had a lower amount of dissolved oxygen, higher electrical conductivity, higher concentration of chlorophyll-a, total phosphorus (TP) and inorganic nitrogen (NI). Macrophyte biomass was significantly higher in monoculture treatments with fish, with this effect being more intense for H. verticillata. When in the same treatment, in the absence of P. ambrosettii, H. verticillata showed greater biomass than E. najas, but with the fish presence, the macrophyte species did not differ in their biomass, indicating that the high concentration of nutrients makes the coexistence of these macrophytes possible. The results found will be useful for future actions to manage invasive species, especially in habitats where they co-occur.
    Description: Espécies invasoras podem impactar negativamente o ambiente invadido. Frequentemente, estas espécies possuem características biológicas que beneficiam outras não nativas e facilitam sua invasão, portanto conhecer os mecanismos de facilitação entre invasoras é essencial para mitigar os danos ao ecossistema. Desta forma, neste estudo testamos a hipótese de que Pterygoplichthys ambrosettii, um cascudo invasor, com hábitos que podem alterar as concentrações de nutrientes (fósforo e nitrogênio) na coluna d'água, afeta positivamente o crescimento de uma espécie de macrófita invasora em detrimento de uma nativa, caracterizando a facilitação ecológica entre espécies invasoras. Para isso um experimento foi conduzido, utilizando a macrófita invasora Hydrilla verticillata e a nativa Egeria najas, na presença e ausência de P. ambrosettii (bem como ambas coocorrendo na presença e ausência do peixe), todos com ocorrência registrada na planície de inundação do alto rio Paraná. Os tratamentos com P. ambrosettii apresentaram menor quantidade de oxigênio dissolvido, maiores valores para a condutividade elétrica, clorofila-a, fósforo total (TP) e nitrogênio inorgânico (NI). A biomassa das macrófitas foi significativamente maior nos tratamentos de monocultura com peixe, sendo este efeito mais intenso para H. verticillata. Quando juntas na ausência de P ambrosettii, H. verticillata apresentou maior biomassa que E. najas, mas com a presença do peixe, as espécies não diferiram em sua biomassa, sugerindo que a alta concentração de nutrientes torna possível a coexistência das macrófitas. Os resultados encontrados se mostram úteis para o conhecimento da biologia destas espécies invasoras, assim como para futuras ações de manejo em pequenos habitats onde estas coocorrem.
    Description: Masters
    Keywords: Pterygoplichthys ambrosettii (Holmberg, 1893) (Siluriformes: Loricariidae) "cascudo blindado" ; Hydrilla verticillata (L.f.) Royle, 1839 (Hydrocharitaceae) "hydrilla" ; Egeria najas Planchon (Hydrocharitaceae) "lodinho branco" ; Macrófitas aquáticas invasoras ; Facilitação, Mecanismos de ; Nutrientes ; Concentração ; Interação ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::M::Macrophytes ; ASFA_2015::F::Floodplains ; ASFA_2015::A::Alien species ; ASFA_2015::N::Nutrition ; ASFA_2015::E::Environmental impact
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 35pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 26
    facet.materialart.
    Unknown
    O estabelecimento de Paspalum repens P. J. Bergius (Poaceae) é positivamente afetado pela mudança do nível d’água, mas negativamente afetado pela densidade de uma macrófita invasora e pela riqueza de espécies. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-08-12
    Description: Changes in water level influence the establishment and ecological interactions developed between aquatic macrophytes.With the aim of investigate how changes in water level, the density of the invasive macrophyte Urochloa arrecta and the species richness influence the establishment of Paspalum repens, we set up two experiments in a greenhouse with three water levels (high, medium and static) and two levels of density and species richness. At the end of the experiments, we measured the following response variables: leaf area surface, shoot biomass, root biomass, total biomass, shoot length, and root length of P. repens. Using the total biomass, we calculated the relative interaction index (RII) to verify the type of ecological interaction developed between P. repens and its neighbors species. Each response variable was analyzed with a two-way ANOVA. Among the results obtained, we highlight: i) the predominantly negative values of the RII, indicating competition between P. repens and its neighbors in all the conditions tested in this work and ii) positive values of leaf area surface and shoot biomass at water levels high, especially in the experiment that analyzed the effect of the density of U. arrecta on P. repens, which highlights the strategies adopted by this species to establish itself in environments with high densities of the invasive species in scenarios of water level changes. Finally, these results indicate the effects of changes in water level, density of U. arrecta and species richness on P. repens, contributing to the understanding of the dynamics of macrophyte communities in freshwater ecosystems.
    Description: Mudanças do nível d’água influenciam o estabelecimento e as interações ecológicas desenvolvidas entre macrófitas aquáticas. Com o objetivo de investigar como mudanças no nível d’água, a densidade da macrófita invasora Urochloa arrecta e a riqueza de espécies influenciam no estabelecimento da macrófita nativa Paspalum repens, foram montados dois experimentos em casa de vegetação com três níveis d’água (alto, médio e estático) e dois níveis de densidade e riqueza de espécies. Ao final do experimento foram mensuradas as seguintes variáveis resposta: superfície da área foliar, biomassa aérea, biomassa da raiz, biomassa total, comprimento aéreo e comprimento da raiz de Paspalum repens. Utilizando a biomassa total, foi calculado o índice de interação relativa (RII) para verificar o tipo de interação ecológica desenvolvida entre P. repens e suas espécies vizinhas. Cada variável resposta foi analisada com uma Anova bifatorial. Dentre os resultados obtidos, destacamos: i) os valores preponderantemente negativos do RII, indicando competição de P. repens com suas vizinhas em todas as condições testadas neste trabalho e ii) valores positivos da superfície da área foliar e biomassa aérea em níveis d’água alto, especialmente no experimento que foi analisado o efeito da densidade de U. arrecta sobre P. repens, o que evidencia as estratégias adotadas por esta espécie para se estabelecer em ambientes com altas densidades da espécie invasora em cenários de mudanças do nível d’água. Esses resultados indicam, por fim, os efeitos da mudança do nível da água, da densidade de U. arrecta e da riqueza de espécies sobre P. repens, contribuindo para o entendimento da dinâmica das comunidades de macrófitas em ambientes aquáticos continentais.
    Description: Masters
    Keywords: Paspalum repens P. J. Bergius (Poaceae) ; Poaceae (Gramineae) “brachiaria” ; Macrófitas aquáticas invasoras emergentes ; Comunidades, Ecologia de ; Competição ; Espécies invasoras ; Estufas ; Experimentos ; ASFA_2015::M::Macrophytes ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::D::Dams ; ASFA_2015::R::Reservoirs (water) ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::A::Alien species ; ASFA_2015::C::Competition ; ASFA_2015::W::Water reservoirs ; ASFA_2015::E::Experimental research
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 49pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 27
    facet.materialart.
    Unknown
    Trends and challenges in alternative states in freshwater ecosystems: emphasizing the role of invasive species in state shifts. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-08-30
    Description: Despite growing interest in the effects of non-native invasive species in changing alternative trophic states in shallow lakes, little is known when it comes to tropical regions. We carried out a systematic review to identify which terms, species, definitions and objectives were most addressed in these studies, as well as to identify possible global patterns and trends regarding the growth of these research over the years and the hot spots of publications. Our results showed that although there was a non-linear growth in the number of studies published in the last three decades regarding state shifts in freshwater environments, only a small number of them addresses the influence that non-native invasive species have in triggering trophic states changes in aquatic environments and even less in shallow lakes. In our discussion, we explore the possible reasons and consequences that these patterns bring to this area of ecology, as well as expand the results and make the work available so that it can be used as recomendation for future projects related to the topic.
    Description: Lagos rasos são os ecossistemas de água doce mais abundantes do planeta, suportam elevada diversidade de espécies e proveem diversos serviços ecossistêmicos, porém, a dinâmica natural desses ecossistemas está ameaçada devido ao estabelecimento de espécies invasoras não nativas. Apesar do crescente interesse acerca dos impactos que espécies invasoras não nativas causam nos ecossistemas invadidos, pouco ainda se sabe sobre a influência delas para a estabilidade e mudança de estado trófico em lagos rasos. Foi realizada uma revisão sistematizada da literatura para identificar quais termos, espécies, definições e objetivos foram mais abordados nesses estudos, assim como identificar possíveis padrões e tendências globais quanto à distribuição das pesquisas ao longo dos anos e seu local de origem. Embora tenha havido um crescimento na quantidade de estudos publicados nas últimas três décadas sobre estados tróficos em ambientes aquáticos, apenas uma pequena quantidade deles aborda a influência das espécies invasoras nãonativas na mudança de estado trófico nestes ecossistemas. Foram exploradas as possíveis razões e as consequências que esses padrões e métodos trazem para essa área da ecologia, de forma que a discussão aqui feita sugere diversas recomendações para futuros trabalhos e pesquisadores considerarem.
    Description: Masters
    Keywords: Ecossistemas aquáticos ; Lagos rasos ; Invasões biológicas ; Eutrofização ; Revisão sistemática ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::L::Lakes ; ASFA_2015::E::Eutrophication ; ASFA_2015::A::Alien species ; ASFA_2015::R::Reviews (literature)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 36pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 28
    facet.materialart.
    Unknown
    Respostas de espécies invasoras de Poaceae ao estresse hídrico, a competição com nativas filogeneticamente próximas e a mudança climática global. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-08-30
    Description: Global climate change has as its main result an increase in the frequency and severity of extreme events, such as longer periods of drought, and more hot days throughout the year, which makes drought events even more severe. Certain plant species have a high invasive potential, which is due to their tolerance to adverse conditions and the recovery of their individuals after some disturbance, which increases the possibility of colonization and establishment in new environments, interfering with native communities. The effect of interspecific competition between the invasive plant Urochloa mutica and the native species Panicum dichotomiflorum was experimentally analyzed on its establishment, resistance and resilience, simulating conditions of extreme water events and the distribution of Panicum dichotomiflorum and Urochloa mutica, particularly in protected areas environmental. The results obtained showed that the native species grew less with the water changes, mainly due to the lack of water, and the invasive species did not show strong growth alterations with the disturbances used. Furthermore, the species were shown to alter the growth variables in competition, impacting the native species more. On the other hand, the species in terms of temporal stability did not change growth and both may have advantages in impacted environments. Regarding the distribution of species, the results showed that the dispersion of the invasive exotic plant will be greater in areas that already have its presence, and also that this species may invade new places, such as Germany and Austria. In a future scenario of global climate change in 2070, this invasive species could occur in protected areas. Regarding the national territory, U. mutica will lose part of its distribution in Brazil, mainly in the north and northeast regions, including areas of protection and conservation. For P. dichotomiflorum, it is possible that it will lose a large part of its natural habitat in the two future scenarios, but it will increase its occurrence in other places, being able to become a potential invasive. Therefore, the results achieved indicate that both species have important characteristics in coping with climate change and show that the native species has an invasive behavior, with information of enormous value to environmental managers, especially in the management work of the two species of Poaceae, which have invasive potential for preserved areas, and in research that evidence areas susceptible to invasion.
    Description: As mudanças climáticas globais tem como principal resultado o aumento na frequência e na severidade de eventos extremos, tais como períodos mais prolongados de seca, e mais dias quentes ao longo do ano, o que torna os eventos de seca ainda mais severos. Certas espécies vegetais possuem alto potencial invasor, que se deve à sua tolerância a condições adversas e à recuperação de seus indivíduos após algum distúrbio, o que aumenta a possibilidade de colonização e estabelecimento em novos ambientes, interferindo em comunidades nativas. Analisou-se experimentalmente o efeito da competição interespecífica da planta invasora Urochloa mutica com a espécie nativa Panicum dichotomiflorum, em seu estabelecimento, resistência e resiliência, simulando condições de eventos hídricos extremos e a distribuição de Panicum dichotomiflorum e Urochloa mutica, particularmente em áreas de proteção ambiental. Os resultados alcançados mostraram que a espécie nativa, cresceu menos com as mudanças hídricas, principalmente pela falta de água e a espécie invasora mostrou não sofrer fortes alterações de crescimento com os distúrbios empregados. As espécies mostraram alterar as variáveis de crescimento em competição, impactando de maior maneira a espécie nativa. Por outro lado, as espécies em termos de estabilidade temporal não alteraram o crescimento e ambas podem apresentar vantagens em ambientes impactados. Em relação à distribuição das espécies, os resultados mostraram que a dispersão da planta exótica invasora será maior em áreas que possuem sua presença, e também que essa espécie poderá invadir novos lugares, como Alemanha e Áustria. Em cenário futuro de mudança climática global em 2070, essa espécie invasora pode ocorrer em áreas protegidas. Com relação ao território nacional, U. mutica perderá parte da sua distribuição no Brasil, principalmente na região norte e nordeste, incluindo áreas de proteção e conservação. Para P. dichotomiflorum, é possível que perdera grande parte de seu habitat natural nos dois cenários futuros, mas aumentará sua ocorrência em outros lugares, podendo se tornar uma invasora em potencial. Portanto, os resultados alcançados indicam que ambas as espécies possuem características importantes no enfrentamento às mudanças climáticas e evidenciam que a espécie nativa apresenta comportamento invasor, com informações de enorme valia para gestores ambientais, especialmente nos trabalhos de manejo das duas espécies de Poaceae, que têm potencial invasor para áreas preservadas, e em pesquisas que evidenciem áreas suscetíveis a invasões.
    Description: Masters
    Keywords: Poaceae (Gramineae) ; Urochloa mutica (Poaceae : Monocotiledônea) ; Panicum dichotomiflorum (Poaceae : Monocotiledônea) ; Macrófitas aquáticas ; Espécies invasoras e nativas ; Espécies invasoras ; Espécies nativas ; Competição ; Mudanças climáticas ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::A::Alien species ; ASFA_2015::C::Competition ; ASFA_2015::C::Climatic changes
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 67pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 29
    facet.materialart.
    Unknown
    Preditores abióticos e bióticos da abundância de uma macrófita nativa e uma macrófita invasora em um reservatório subtropical. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-24
    Description: The invasion success of non-native species depends on several factors, and native populations and biotic characteristics of non-native environments can offer resistance to non-native species development. Reservoirs can facilitate submerged macrophyte invasion once it modifies the environment and provides favorable abiotic conditions to macrophyte establishment and development. However, previous colonization of native species can resist the development of invasive ones through priority effects. In this investigation we used large data-set (1120 samplings during 4 years) obtained in the Itaipu Reservoir (Brazil/Paraguay) to assess the relationship between the abundance of the native submerged macrophyte Egeria najas and of the invasive Hydrilla verticillata and the water level, littoral slope and Secchi disk depth. We also investigated how the concomitant and previous abundance of both macrophytes correlates. A spatial-temporal modeling was applied using Integrated Nested Laplace Approximations method, which controls the effect of spatial-temporal autocorrelation. Our results indicate an important role of water transparency, littoral slope and water level oscillations (in terms of amplitude and increased hydrometric level), in a short period of time (30 days) for the temporal dynamics of the abundance of both species. However, alterations of the hydrometric levels and of the littoral slope affected H. verticillata to a greater extent than E. najas. In addition, the abundance of each species was related with its own abundance in previous samplings, highlighting the importance of vegetative propagule pressure and resistance structures for population recovery. The magnitude of the interaction between both species in concomitant occurrence in the same site was abundance dependent.
    Description: O sucesso da invasão de espécies não nativas depende de vários fatores. Populações nativas e características bióticas de ambientes não nativos podem oferecer resistência ao desenvolvimento de espécies não nativas. Porém, a colonização prévia de espécies nativas pode impor resistência ao desenvolvimento de espécies invasoras por meio de efeitos de prioridade. Nesta investigação utilizou-se um grande conjunto de dados (1120 amostragens durante 4 anos) obtidos Reservatórios podem facilitar a invasão de macrófitas submersas, uma vez que modificam o ambiente e fornecem condições abióticas favoráveis para o estabelecimento e desenvolvimento de macrófitas no reservatório de Itaipu (Brasil/Paraguai) para avaliar a relação entre a abundância da macrófita submersa nativa Egeria najas e da invasora Hydrilla verticillata e o nível da água, declividade litorânea e profundidade do disco de Secchi. Também se investigou, como a abundância concomitante e prévia de ambas as macrófitas se correlaciona. Uma modelagem espaço-temporal foi aplicada usando o método de Aproximações Aninhadas Integradas de Laplace, que controla o efeito da autocorrelação espaço-temporal. Os resultados indicam um importante papel da transparência da água, declividade litorânea e oscilações do nível da água (em termos de amplitude e aumento do nível hidrométrico), em um curto período de tempo (30 dias) para a dinâmica temporal da abundância das duas espécies. Contudo, as alterações dos níveis hidrométricos e do declive litorâneo afetaram mais H. verticillata em comparação a E. najas. Ademais, a abundância de cada espécie foi relacionada com a sua própria abundância em amostragens anteriores, evidenciando a importância da pressão do propágulo vegetativo e das estruturas de resistência para a recuperação populacional. A magnitude da interação entre as duas espécies ao ocorrerem concomitantemente no mesmo ponto foi dependente da abundância.
    Description: Masters
    Keywords: Ecologia de reservatórios ; Macrófitas aquáticas submersas nativas e invasoras ; Abundância ; Preditores abióticos e bióticos ; Nível da água ; Abundância prévia ; Efeitos de prioridade ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::W::Water levels ; ASFA_2015::A::Abundance ; ASFA_2015::T::Temporal variations ; ASFA_2015::P::Prediction ; ASFA_2015::A::Abiotic factors ; ASFA_2015::R::Reservoirs (water)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 36pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 30
    facet.materialart.
    Unknown
    Diatomáceas como bioindicadoras em estudo de longa duração na planície de inundação do alto rio Paraná. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-24
    Description: Freshwater ecosystems such as the Upper Paraná River floodplain are constantly subjected to environmental changes caused by natural disturbances, but mainly by anthropogenic impacts (such as dams), which have drastically affected the biodiversity of these aquatic systems. One way to assess the rates of environmental change in systems such as plains is through biomonitoring studies on large temporal scales, with diatoms being excellent bioindicators in determining environmental changes in different aquatic ecosystems. Based on this, the temporal pattern of the periphytic diatom community of a lake in the upper Paraná River floodplain was investigated in order to seek patterns that reflect the environmental changes in this plain, covering studies with different approaches, such as ecology, taxonomic and of environmental education. As a result of these different studies, it is noteworthy that the association of the taxonomic and functional approach in the components of beta diversity was extremely important for the interpretation of variation in the composition of diatom species in a long time series, especially when considering the importance of the contribution beta diversity site - LCBD. It was also sought to highlight the use of diatoms as indicators in determining hydrological changes, reinforcing the need for continuous monitoring of the region, in order to follow the direction of ecological changes, both hydrological and climatic in this plain. The importance of taxonomic studies in the plain was also highlighted in this thesis, in order to better understand the local biodiversity of diatoms, since new species such as Staurosirella paranaensis are being registered. Finally, this thesis includes a proposal for educational games on microalgae and their ecological importance in the environmental indication of aquatic bodies, to emphasize the relevance of environmental education in the research, teaching and extension process.
    Description: Ecossistemas de água doce como a planície de inundação do alto rio Paraná estão constantemente submetidos a mudanças ambientais causadas por distúrbios naturais, mas principalmente por impactos antrópicos (como barramentos), que tem afetado drasticamente a biodiversidade desses sistemas aquáticos. Uma forma de avaliar as taxas de alterações ambientais em sistemas como as planícies, é por meio dos estudos de biomonitoramento em grandes escalas temporais, sendo as diatomáceas excelentes bioindicadoras na determinação de mudanças ambientais nos diversos ecossistemas aquáticos. Com base nisso, foi investigado o padrão temporal da comunidade de diatomáceas perifíticas de um lago da planície de inundação do alto rio Paraná, a fim de buscar padrões que refletem as alterações ambientais desta planície, abrangendo estudos com diferentes abordagens, como ecologia, taxonômica e de educação ambiental. Como resultado destes diferentes estudos, ressalta-se que a associação da abordagem taxonômica e funcional nos componentes da diversidade beta foi de extrema importância para a interpretação de variação da composição de espécies de diatomáceas em uma longa série temporal, principalmente quando consideramos a importância da contribuição local da diversidade beta - LCBD. Também se buscou evidenciar o uso das diatomáceas como indicadores na determinação das alterações hidrológicas, reforçando a necessidade de um monitoramento contínuo da região, no intuito de acompanhar a direção das mudanças ecológicas, tanto hidrológicas quanto climáticas desta planície. A importância dos estudos taxonômicos na planície, também foi destaque nesta tese, a fim de conhecer melhor a biodiversidade local de diatomáceas, uma vez que novas espécies estão sendo registradas, como a Staurosirella paranaensis. Por fim, esta tese engloba uma proposta de jogos didáticos sobre microalgas e a importância ecológica delas na indicação ambiental de corpos aquáticos, no intuito de ressaltar a relevância da educação ambiental no processo de pesquisa, ensino e extensão.
    Description: PhD
    Keywords: Algas perifíticas ; Diatomáceas ; Microalgas perífiticas de água doce ; Comunidades, Ecologia de ; Bioindicadores ; Mudanças climáticas ; Taxonomia ; Jogos didáticos ; ASFA_2015::A::Algae ; ASFA_2015::D::Diatoms ; ASFA_2015::P::Phytoplankton ; ASFA_2015::B::Bioindicators ; ASFA_2015::E::Environmental monitoring ; ASFA_2015::T::Taxonomy ; ASFA_2015::F::Freshwater ecology
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 140pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 31
    facet.materialart.
    Unknown
    Impacto do barramento de um rio amazônico sobre os padrões de sincronia de grupos funcionais fitoplanctônicos. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-24
    Description: The degree at which populations are correlated in space is called spatial synchrony and can be affected by interspecific interactions, dispersion, and large-scale environmental factors, i. e. Moran effect. The study of this phenomenon can help understanding the temporal stability of communities and the underlying mechanisms. The influence of damming in a river from the Amazon basin (Santo Antônio do Jari HPP) on the synchrony of the environment and the phytoplankton community was evaluated, both for the total density and for different Reynolds functional groups. Was investigated whether the effects would be similar for the main channel (Jari River), tributaries, and for the total area (Jari + tributaries). The mean synchrony values and the confidence intervals of each abiotic variable, functional group, and the total density were estimated for the total area, Jari River and tributaries. Matrix-based multiple regression were also performed to identify the most important drivers of synchrony of the phytoplankton. Changes in the synchrony patterns were verified after the damming. The temporal dynamics of environmental variables, total density and of some functional groups was more synchronous when considering only the Jari River, than the total area or only tributaries. Environmental synchrony and environmental distance were the main mechanisms behind synchrony for some functional groups.
    Description: O grau de correlação de populações no espaço é denominado sincronia espacial e pode ser afetado por interações interespecíficas, dispersão e fatores ambientais de ampla escala, (i. e., efeito Moran). O estudo deste fenômeno pode colaborar na compreensão da estabilidade temporal das comunidades e a descobrir quais os mecanismos associados ao processo. Avaliou-se a influência de um barramento em um rio da bacia Amazônica (UHE Santo Antônio do Jari) sobre a sincronia espacial ambiental e do fitoplâncton do rio Jari e tributários. Mensurou-se a sincronia (total, média e intervalo de confiança) para cada variável abiótica, para a densidade de toda a comunidade e para cada grupo funcional de Reynolds, considerando a área total (11 locais - rio Jari + tributários), apenas rio Jari (cinco locais) e apenas tributários (seis locais), utilizando uma série temporal de oito anos. Regressões matriciais múltiplas foram utilizadas para identificar os fatores determinantes da sincronia do fitoplâncton. Verificou-se mudanças nos padrões de sincronia após o barramento. A dinâmica temporal das variáveis ambientais, da densidade de toda a comunidade e de alguns grupos funcionais apresentou-se mais sincrônica quando considerado somente o rio Jari, do que toda a área ou somente os tributários. Em geral, a distância ambiental mostrou-se o preditor mais importante para explicar a sincronia espacial do que a distância geográfica.
    Description: Masters
    Keywords: Fitoplâncton de água doce ; Comunidades, Ecologia de ; Abordagem funcional ; Impacto ambiental ; Sincronia espacial ; Barramento ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::P::Phytoplankton ; ASFA_2015::M::Monitoring ; ASFA_2015::E::Environmental impact ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::R::Reservoirs (water)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 42pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 32
    facet.materialart.
    Unknown
    Ecologia trófica de larvas de peixes neotropicais: interações intra e interespecíficas e relação predador-presa. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-24
    Description: The survival and growth of fish larvae during ontogeny are related to the ability to obtain adequate food, providing subsidies for individuals reach the adult age. The foraging capacity, availability and abundance of prey and morphological development, especially swimming performance and visual acuity are important factors in reproductive success. In this study, the aspects related to feeding during the ontogeny of fish larvae from a floodplain system were analyzed, evaluating the coexistence capacity and the predator-prey interaction. Specifically, the objectives were (1) to analyze the inter and intraspecific variations in the diet of three invasive fish species (Auchenipterus osteomystax, Plagioscion squamosissimus and Hypophthalmus oremaculatus) during their initial ontogeny and the relationship with coexistence; and (2) to apply a new approach in trophic ecology studies during ontogeny, evaluating the interaction and organization of the predator-prey network, using A. osteomystax as model. The larvae of invasive fish species had different diets inter and intraspecifically, low diet overlap and high niche breadth primarily for P. squamosissimus. The coexistence of larvae of these species is probably possible due to low competition, differentiation of trophic guilds, resource partitioning and trophic plasticity. Regarding the predator-prey network, A. osteomystax showed a nested structure, low connectivity and a pattern of segregation in resource consumption. The larvae fed exclusively on aquatic insects, impacting the robustness of the network when the most frequent prey in the diet is removed, here represented by Diptera and Chironomidae pupa. Furthermore, the correlation between metric variables and morphological networks showed that the species is of more general position as the network develops, increasing its capacity predation. Both studies demonstrated the importance of knowing the species-habitat interaction and the processes that govern prey capture, avoiding inter and intraspecific competition through resource partitioning and behavioral and foraging changes during ontogeny.
    Description: A sobrevivência e o crescimento das larvas de peixes durante a ontogenia estão relacionados com a capacidade de se obter alimento adequado, o qual fornece subsídios para que os indivíduos alcancem a vida adulta. A capacidade de forrageamento, a disponibilidade e abundância de presas e o desenvolvimento morfológico, principalmente da capacidade natatória e acuidade visual são fatores preponderantes no sucesso reprodutivo. Analisou-se, os aspectos relacionados à alimentação durante a ontogenia das larvas de peixes de um sistema de planície de inundação, avaliando a capacidade de coexistência e a interação predador-presa. Especificamente os objetivos foram (1) analisar as variações inter e intraespecíficas da dieta de três espécies de peixes invasoras (Auchenipterus osteomystax, Plagioscion squamosissimus e Hypophthalmus oremaculatus) durante a sua ontogenia inicial e a relação com a coexistência; (2) aplicar uma nova abordagem em estudos de ecologia trófica durante a ontogenia, avaliando a interação e organização da rede predador-presa, usando como modelo A. osteomystax. As larvas apresentaram dietas distintas tanto inter, quanto intraespecificamente, baixa sobreposição alimentar a alta amplitude de nicho principalmente para P. squamosissimus. A coexistência das larvas destas espécies é possível provavelmente devido à baixa competição, diferenciação de guildas tróficas, particionamento de recursos e plasticidade trófica. Em relação à rede predador-presa, A. osteomystax apresentou estrutura aninhada, baixa conectância e um padrão de segregação no consumo de recursos. As larvas desta espécie alimentaram-se exclusivamente de insetos aquáticos, com impacto na robustez da rede quando ocorre a remoção de presas mais frequentes na dieta, aqui representada por pupa de Diptera e Chironomidae. A correlação entre variáveis morfológicas e as métricas de redes mostrou que a espécie assume uma posição mais generalista na rede conforme ocorre seu desenvolvimento, aumentando sua capacidade de predação. Ambos os estudos demonstraram a importância de se conhecer a interação espécie-habitat e os processos que regem a captura de presas, evitando a competição inter e intraespecífica através do particionamento de recursos e mudanças comportamentais e de forrageamento durante a ontogenia.
    Description: PhD
    Keywords: Peixes de água doce ; Ictioplâncton de água doce ; Larvas ; Ecologia ; Alimentação ; Relação presa-predador ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::I::Ichthyoplankton ; ASFA_2015::L::Larvae ; ASFA_2015::P::Predators ; ASFA_2015::P::Prey ; ASFA_2015::F::Floodplains ; ASFA_2015::T::Trophic relationships ; ASFA_2015::F::Food chains
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 66pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 33
    facet.materialart.
    Unknown
    Avaliando os preditores e padrões da distribuição de comunidades aquáticas em sistemas de planície de inundação Neotropical: uma abordagem baseada em análises de diversidade-beta. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Evaluating patterns and predictors of species distribution is important, because anthropogenic actions have been threatening global biodiversity. Hence, researchers have used measures of beta-diversity, defined as the variation in species composition amongst sites of a given area. Several measures of beta-diversity have been created, because using this approach makes it simple to elaborate and test ecological hypotheses, considering species distribution. Here, it was aimed to contribute to the knowledge about drivers and patterns of distribution amongst aquatic communities in Neotropical riverine floodplains. For this, this thesis was fractionated into two approaches, in which was used two different methods to measure beta-diversity. In the first approach, it was assessed the environmental and spatial factors affecting the beta-diversity facets (species-, traits- and phylogeny-based), and their components (Beta-total, replacement and richness difference), of ostracod communities associated with macrophytes, in the Upper Paraná River floodplain. Furthermore, it was compared these factors amongst the different life forms: emergent, rooted floating, rooted submerged, free submerged and free floating. In the second approach, it was used the local contribution to beta-diversity approach (LCBD) to evaluate the drivers and patterns of ecological uniqueness of the sites, in terms of species composition, in four floodplain systems, Amazon, Araguaia, Pantanal and Paraná. It was gathered data on community composition for eight aquatic biological groups: phytoplankton, ciliates, testate amoebae, rotifers, cladocerans, copepods, ostracods and fish. In general, environmental filtering was more important in explaining distribution patterns of communities, and the species sorting mechanism might be responsible for them, within and amongst the floodplains. In the first approach, different environmental and spatial factors influenced each of the beta-diversity facets of ostracod communities (species-, traits- and phylogeny-based). The factors affecting ostracod beta-diversity were different amongst the macrophyte life forms, evidencing the importance of considering them in ecological surveys of associated communities. In the second approach, the Amazon and Paraná floodplains had higher uniqueness in terms of species composition, showing the importance of conservation actions in these ecosystems. Furthermore, the drivers (e.g. environmental variables) and patterns of LCBD were different amongst the different biological groups, evidencing the need to include a variety of taxa. It was considered that the results of this thesis, based on beta-diversity analyses, contributed to a better understanding of drivers and patterns of distribution amongst communities in Neotropical floodplains. This is because researchers can use them as a reference in conservation and restoration plans for these systems and to prevent the destruction of areas with high conservation value, for example, by the construction of dams and reservoirs.
    Description: Avaliar os padrões e preditores da distribuição de espécies é importante, visto que as ações antrópicas têm ameaçado a biodiversidade global. Para isso, pesquisadores têm usado medidas de diversidade-beta, definida como a variação na composição de espécies entre os locais de uma determinada área. Várias medidas de diversidade-beta têm sido produzidas, visto que através desta abordagem tem sido simples elaborar e testar hipóteses ecológicas, considerando a distribuição de espécies. O objetivo desta tese foi contribuir para o conhecimento de padrões e preditores da distribuição de comunidades aquáticas de planícies de inundação Neotropicais. Assim, foi fracionada em duas abordagens, onde foram utilizados dois métodos diferentes de medida de diversidade-beta. Na primeira abordagem, foi avaliado os fatores ambientais e espaciais que afetam as facetas da diversidade-beta (baseado nas espécies, traços e filogenia) e seus componentes (beta-total, replacement e richness difference), das comunidades de ostrácodes associados a diferentes formas de vida de macrófitas aquáticas, na planície de inundação do alto rio Paraná. Esses fatores foram comparados entre as diferentes formas de vida: emergentes, submersas e flutuantes enraizadas e submersas e flutuantes livres. Na segunda abordagem, foi utilizada a análise da contribuição local para a diversidade-beta (LCBD) para avaliar os preditores e padrões da singularidade dos locais, considerando a composição de espécies, em quatro planícies de inundação, Amazonas, Araguaia, Pantanal e Paraná. Para isso, foram analisados oito grupos biológicos aquáticos: fitoplâncton, ciliados, amebas testáceas, rotíferos, cladóceros, copépodes, ostrácodes e peixes. Em geral, os filtros ambientais foram mais importantes para explicar os padrões de distribuição das comunidades, e o mecanismo species sorting pode ser responsável por tais padrões, dentro e entre as planícies de inundação. Na primeira abordagem, diferentes fatores ambientais e espaciais influenciaram cada uma das facetas da diversidade-beta de ostrácodes (baseadas nas espécies, traços e filogenia). Ademais, os fatores que afetaram a diversidade-beta de ostrácodes foram diferentes entre as formas de vida das macrófitas aquáticas, evidenciando a necessidade de considerá-las em estudos ecológicos considerando as comunidades associadas. Na segunda abordagem, as planícies de inundação do Amazonas e Paraná foram as mais singulares em termos de composição de espécies, que avaliam a importância da preservação destes ecossistemas. Os padrões e preditores (variáveis ambientais) da LCBD foram diferentes entre os grupos biológicos, confirmando a importância de incluir diferentes taxa. Os resultados desta tese, baseados em análises de diversidade-beta, contribuíram para um melhor entendimento sobre os padrões e preditores da distribuição de comunidades aquáticas de planícies de inundação Neotropicais. Dessa forma, eles podem ser usados por pesquisadores como referência para planos de restauração e conservação destes ecossistemas, assim como evitar que áreas de grande valor de conservação sejam impactadas, por exemplo, pela construção de reservatórios e hidroelétricas.
    Description: PhD
    Keywords: Organismos aquáticos de água doce ; Fauna aquática de água doce ; Comunidades, Ecologia de ; Diversidade-beta ; Estrutura ; Padrões e preditores ; Fatores espaciais e ambientais ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Aquatic communities ; ASFA_2015::E::Environmental factors ; ASFA_2015::P::Phylogeny ; ASFA_2015::C::Conservation ; ASFA_2015::F::Floodplains ; ASFA_2015::A::Aquatic organisms ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::B::Biodiversity
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 110pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 34
    facet.materialart.
    Unknown
    De monitoramentos locais até um inventário global das introduções de macrófitas aquáticas – insights para monitoramento e prevenção de invasões de espécies. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Aquatic ecosystems are especially vulnerable to species invasion due to their extent, diversity of habitats, and inherent dynamics. Invasive aquatic macrophytes are of great concern because of their great influence on aquatic ecosystems. In this thesis, we sought to contribute to the field of biological invasions of aquatic macrophytes at regional and global levels using knowledge pertinent to monitoring and preventing the introduction of species. Given that, one of the most concerning invasive species in the world, Hydrilla verticillata (L.f.) Royle, was evaluated in different types of environments in a subtropical floodplain. The relationship of occurrences of this species with its main abiotic predictors was investigated, as well as its relationship with the native (equivalent) species Egeria najas Planch. right after its detection and 10 years later. This work contributed with insights regarding the biotic interactions of invaders and natives as well as changes in environmental predictors that highlight anthropogenic impacts that deserve attention. A second work was carried out to leverage knowledge about invasive aquatic macrophytes at a global level. A compilation of data from several available sources was carried regarding the most common pathways of introduction of aquatic macrophytes to identify the regions of origin and destination of these species and their respective functional groups. Such information is crucial for the determination of public policies and management strategies to avoid the introduction of unwanted species. In summary, this thesis helps the characterization of aquatic macrophyte invasions aiming at their prevention.
    Description: Os ecossistemas aquáticos são especialmente vulneráveis à invasão de espécies devido a sua grande extensão, diversidade de habitat e a dinâmica inerente destes habitat. Macrófitas aquáticas invasoras geram muita preocupação devido à sua grande influência nos ecossistemas aquáticos. Buscou-se contribuir para o campo das invasões biológicas de macrófitas aquáticas em nível regional e global com conhecimentos pertinentes ao monitoramento e prevenção de espécies introduzidas. Na primeira abordagem avaliou-se a invasão de uma das espécies de macrófitas invasoras mais preocupantes do mundo, Hydrilla verticillata (L.f.) Royle, em diferentes tipos de ambientes de uma planície subtropical. Investigou-se a relação das ocorrências desta espécie com seus principais preditores abióticos, bem como sua relação com a espécie nativa (morfologicamente semelhante) Egeria najas Planch. nos primeiros anos de sua introdução e 10 anos depois. Tal trabalho destacou as interações bióticas entre a espécie invasora e a nativa bem como mudanças nos preditores ambientais que sugerem impactos antrópicos merecedores de atenção. Uma segunda abordagem foi realizada com o intuito de alavancar o conhecimento sobre macrófitas aquáticas invasoras em um nível global. Foi realizada uma compilação de dados acerca das vias e caminhos de introdução das macrófitas aquáticas a fim de identificar as regiões de origem e destino destas espécies e de seus respectivos grupos funcionais. Tais informações são cruciais para a determinação de políticas públicas e estratégias de manejo para evitar a introdução de espécies indesejadas. Em suma, os resultados das duas abordagens dão suporte a caracterização das invasões de macrófitas aquáticas visando sua prevenção.
    Description: PhD
    Keywords: Macrófitas aquáticas ; Espécies invasoras ; Comunidades, Ecologia de ; Diversidade de espécies ; Impacto ambiental ; Monitoramento e prevenção ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::A::Alien species ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::S::Species diversity ; ASFA_2015::E::Environmental impact ; ASFA_2015::E::Environmental monitoring ; ASFA_2015::A::Aquatic environment
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 152pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 35
    facet.materialart.
    Unknown
    Traços e grupos funcionais do fitoplâncton na avaliação da redundância funcional e restauração lacustre em planícies de inundação. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Biological communities derive not from a random distribution of organisms but are the result of many processes that include abiotic factors, biotic interactions, and dispersion. The impact of human activities has affected the structure and functioning of ecological communities at an accelerated pace. The phytoplankton community represents a major primary producer of aquatic environments, therefore factors that interfere with its structure and dynamics can also impact other trophic levels in the ecosystem. In this perspective, functional redundancy was the central theme of the first paper, whose aim was to investigate the response of redundancy in phytoplankton communities to environmental factors, when measured for functional groups and functional traits. For this, six years of data collected quarterly (2008 to 2013) from two temperate and three subtropical lakes were used. Traits and groups were efficient to measure this attribute, however, the traits were more efficient when the structuring process of the communities was the environmental filtering. The functional traits most effectively explain the relationship between redundancy and environment. In the second paper, the influence of hydrodynamics, landscape and resources on the structure of the phytoplankton community during a floodplain lake restoration process was evaluated. As expected, factors related to hydrodynamics and resources (light and nutrients) were determinants for biovolume and density. The relative importance of landscape to community attributes increased over time of restoration. Cyanobacteria were dominant at the beginning of the restoration process, followed by phytoflagellates and diatoms. Aiming to disseminate science, the third article presents basic concepts of phytoplankton ecology and the main results related to the themes of the two scientific papers. In summary, the functional approach in phytoplankton ecology stands out as an important tool for the development of community ecology and for restoration and management of aquatic ecosystems projects.
    Description: Comunidades biológicas não são combinações aleatórias de espécies e sim o resultado de diversos processos que incluem fatores abióticos, interações bióticas e dispersão. As ações antrópicas têm afetado a estrutura e funcionamento das comunidades ecológicas em ritmo acelerado. A comunidade fitoplanctônica representa o principal produtor primário dos ambientes aquáticos, portanto fatores que interferem na sua estrutura e dinâmica, também podem causar impactos nos demais níveis tróficos do ecossistema. Nessa perspectiva, a redundância funcional foi tema central da primeira abordagem, cujo objetivo foi investigar a resposta da redundância de comunidades fitoplanctônicas, diante de fatores ambientais, quando medida para grupos e traços funcionais. Para isso utilizou-se seis anos de dados coletados trimestralmente (2008 a 2013) referentes a dois lagos temperados e três subtropicais. Traços e grupos foram eficientes para medir esse atributo, entretanto os traços foram mais eficientes quando o processo estruturador das comunidades foi a filtragem ambiental. Os traços funcionais do fitoplâncton explicaram de maneira mais eficaz a relação entre redundância e ambiente. Na segunda abordagem, avaliou-se a influência da hidrodinâmica, paisagem e recursos sob a estrutura da comunidade fitoplanctônica durante um processo de restauração de um lago de planície de inundação. Como esperado, os fatores relacionados a hidrodinâmica e aos recursos (luz e nutrientes) foram determinantes para o biovolume e densidade. A importância relativa da paisagem para os atributos da comunidade aumentou ao longo do tempo de restauração. Cianobactérias foram dominantes no início da restauração, seguidas de fitoflagelados e diatomáceas. Com o objetivo de divulgar a ciência, a terceira abordagem apresenta conceitos básicos do fitoplâncton e agrupa os principais resultados referentes a redundância funcional e restauração lacustre. Enfatiza-se o uso de traços e grupos funcionais do fitoplâncton como uma importante ferramenta para o desenvolvimento da ecologia de comunidades e para projetos de restauração e manejo dos ecossistemas aquáticos.
    Description: PhD
    Keywords: Fitoplâncton de água doce ; Comunidades, Ecologia de ; Redundância funcional ; Restauração lacustre ; ASFA_2015::P::Phytoplankton ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::F::Floodplains ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::E::Ecosystems ; ASFA_2015::L::Lakes ; ASFA_2015::A::Algae
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 94pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 36
    facet.materialart.
    Unknown
    Influência do tamanho do habitat e da cobertura de dossel sobre as teias tróficas da microbiota em fitotelmatas de Quesnelia arvensis (Bromeliaceae). (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: The aquatic communities in phytotelmata are structured by several environmental factors, and they act in the trophic and non-trophic interactions of these environments. Phytotelmata are micro-ecosystems of fresh water, rich in species and are considered an excellent study model. Here, we use plants from the family Bromeliaceae of the species Quesnelia arvensis, to investigate the relationships between biotic and abiotic variables and their effects on interactions in phytotelmata. Our hypothesis was that habitat size and canopy cover gradients would determine the abundance of microbiota communities and their interactions. We carried out samples on bromeliads located in the state park of the Parque Estadual da Ilha do Cardoso - SP, Brazil, in different canopy cover gradients, in addition we selected plants of different sizes, to investigate the effects of habitat size. To check the interactions between the variables and score the interactions (positive and negative) we use the lasso graphical method, which exemplifies these interactions through a network graph. Also, we performed a simple regression analysis in to determine the correlations between biotic and abiotic variables. Our results indicate that the canopy cover and the size of the habitat (water volume) were the most important variables in interactions in phytothelmata. The canopy cover presented the greatest amount of negative connections, mainly with the levels of ammonia, Culicidae larvae and algae in general, with the exception of phyto-flagellates. In contrast, habitat size showed strong positive connections with rotifers and copepods and did not show any negative connection with other variables. Finally, our results demonstrate that among the set of factors analyzed, canopy cover and habitat size were in fact the most representative, as expected.
    Description: As comunidades aquáticas em fitotelmatas são estruturadas por vários fatores ambientais que atuam nas interações tróficas e não tróficas desses ambientes. Fitotelmatas são microecossistemas de água doce, ricos em biodiversidade e são considerados um excelente modelo de estudo. Foram utilizadas plantas da família Bromeliaceae da espécie Quesnelia arvensis, com o objetivo de investigar as relações entre as variáveis bióticas e abióticas e seus efeitos sobre as interações da microbiota desses ambientes. A hipótese testada foi de que o tamanho do habitat e os gradientes de cobertura de dossel determinariam a abundância das comunidades da microbiota e suas interações. Foram realizadas coletas em bromélias localizadas no Parque Estadual da Ilha do Cardoso – SP, Brasil, em diferentes gradientes de cobertura de dossel e tamanhos, a fim de investigar os efeitos do tamanho do habitat. Para verificar as interações entre as variáveis e pontuar as interações (positivas e negativas) foi utilizado o método graphical lasso, que exemplifica essas interações através de um gráfico de rede. Também, foi realizada uma análise de regressão simples a fim de determinar as correlações entre as variáveis bióticas e abióticas. Os resultados encontrados apontam que a cobertura de dossel e o tamanho do habitat foram as variáveis mais importantes nas interações em fitotelmatas. A cobertura de dossel apresentou a maior quantidade de conexões negativas, principalmente com os níveis de amônia, larvas de Culicídeos e algas em geral, com exceção dos fitoflagelados. Em contrapartida, o tamanho do habitat apresentou fortes conexões positivas com os rotíferos e os copépodes e não apresentou nenhuma conexão negativa com outras variáveis. Por fim, corroborando nossa hipótese, os resultados desse estudo demonstram que, dentre o conjunto de fatores analisados, a cobertura de dossel e o tamanho do habitat foram os mais representativos para a estruturação trófica das comunidades da microbiota assim como esperado.
    Description: Masters
    Keywords: Fitotelmatas ; Microssistemas de água doce ; Microbiotas aquáticas de água doce ; Interações tróficas ; Variáveis bióticas e abióticas ; Comunidades, Ecologia de ; Bromeliaceae ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::E::Ecosystems ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::A::Aquatic ecology ; ASFA_2015::T::Temperature ; ASFA_2015::T::Trophic relationships ; ASFA_2015::P::Predators ; ASFA_2015::P::Plants
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 32pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 37
    facet.materialart.
    Unknown
    Efeito do aquecimento e da disponibilidade de recursos provenientes de detritos sobre a microbiota aquática. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Freshwater environments are the most vulnerable to climate change, and projected increases in temperature over the coming decades bring an unfavorable scenario for aquatic organisms. Warming, when combined with nutrient availability, can trigger even more complex interactions in the functioning of microbial food webs. The aim of this study was to evaluate the influence of warming and resource availability from detritus on the community structure of freshwater aquatic microbiota (richness, density and beta diversity) using natural microcosms (tank bromeliads) as a model system. Warming was simulated with temperature increase projections for the next decades following the Intergovernmental Panel on Climate Change. The dry mass (g) of coarse particulate organic matter (CPOM) from each bromeliad was used as a measure for resource availability (detritus biomass). Detritus biomass caused a negative effect on algal and microfauna density, and for total algal richness. Detritus biomass explained the variation for almost all components of microfauna beta diversity, except for the replacement component (βrepl), where warming was responsible for this variation. For algae the interaction between warming and detritus biomass was most important in explaining the variation in total beta and βrepl, while for the richness difference component (βrich) this variation was explained only by detritus biomass. In summary, the results obtained suggest that warming and increased detritus biomass acted strongly on the structuring of the communities, reducing the density and richness of the aquatic microbiota. Furthermore, the results provide evidence that temperature can increase the dissimilarity of communities of groups of organisms in the heterotrophic plot (microfauna), mainly by species substitution.
    Description: Os ambientes de água doce são os mais vulneráveis às alterações climáticas e, as projeções de aumento da temperatura para as próximas décadas, trazem um cenário desfavorável para organismos aquáticos. O aquecimento, quando combinado com disponibilidade de nutrientes, pode desencadear interações ainda mais complexas no funcionamento das teias alimentares microbianas. O objetivo deste estudo foi avaliar a influência do aquecimento e da disponibilidade de recursos proveniente de detritos na estrutura das comunidades da microbiota aquática de água doce (riqueza, densidade e diversidade beta), usando microcosmos naturais (bromélias-tanque) como sistema modelo. O aquecimento foi simulado com as projeções de aumento da temperatura para as próximas décadas seguindo o Painel Intergovernamental sobre Mudanças Climáticas. A massa seca (g) de matéria orgânica particulada grosseira (CPOM) de cada bromélia foi usada como medida para a disponibilidade de recurso (biomassa de detritos). A biomassa de detritos causou efeito negativo sobre a densidade de algas e da microfauna, e para a riqueza total de algas. A biomassa de detritos explicou a variação para quase todos os componentes da diversidade beta da microfauna, exceto para o componente replacement (βrepl), em que o aquecimento foi responsável por essa variação. Para as algas a interação entre aquecimento e biomassa de detritos foi o mais importante para explicar a variação da beta total e βrepl, enquanto que para o componente de diferença de riqueza (βrich) essa variação foi explicada apenas pela biomassa de detritos. Em síntese, os resultados obtidos indicam que o aquecimento e o aumento da biomassa de detritos atuaram fortemente na estruturação das comunidades, reduzindo a densidade e a riqueza da microbiota aquática. Outrossim, os resultados trazem evidências de que a temperatura pode aumentar a dissimilaridade das comunidades de grupos de organismos da parcela heterotrófica (microfauna), principalmente por substituição de espécies.
    Description: Masters
    Keywords: Microbiota aquática de água doce ; Microfauna aquática de água doce ; Comunidades, Ecologia de ; Perda de espécies ; Mudanças climáticas ; Temperatura e nutrientes ; ASFA_2015::F::Fresh water ; ASFA_2015::A::Aquatic communities ; ASFA_2015::M::Microfauna ; ASFA_2015::A::Aquatic fauna ; ASFA_2015::M::Microcosms ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Climatic changes ; ASFA_2015::B::Biodiversity
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 37pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 38
    facet.materialart.
    Unknown
    Estruturação da comunidade de microcrustáceos (Copepoda, Ostracoda) associados a ambientes de fitotelmata em Nidularium innocentii Lem. (Bromeliaceae). (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Since the classic Forbes publication “The Lake as a Microcosm” in 1887, scientific research on freshwater ecosystems has been boosted due to the formulation of the first limnological concepts. For a long period, scientific research aimed at the spatial distribution of communities was focused on large water bodies, leaving aside studies in small freshwater environments, such as bromeliad phytotelmata. The first work of this thesis carried out a scientometric analysis in virtual databases on bromeliad phytotelmata, and 140 publications were found. South America was the region with the highest number of articles published. Most articles presented predictive designs, focusing on community ecology. Insecta was the most recorded group of organisms. In the second article, it was investigated how the microcrustacean community (composition, abundance and richness) is associated with the phytotelmata of Nidularium innocentii Lem. was influenced by the limnological variables present along the altitudinal gradient. The study was carried out in Serra da Prata, in the state of Paraná. The results did not show a distribution pattern in species richness along the altitudinal gradient, refuting the central domain effect hypothesis among others. However, there were dissimilarities in the composition of microcrustacean species in relation to altitudes. The different climatic types and vegetation types directly influenced the environmental variables in the phytotelmata microcosms, leading to similarities in species composition between altimetric elevations located in the same climatic region and dissimilarities between different climates.
    Description: Desde a clássica publicação de Forbes “The Lake as a Microcosmo”, em 1887, pesquisas científicas em ecossistemas dulcícolas foram impulsionadas devido à formulação dos primeiros conceitos limnológicos. Durante um longo período, pesquisas científicas direcionadas à distribuição espacial de comunidades foram voltadas aos grandes corpos hídricos, deixando de lado estudos em pequenos ambientes de água doce, como fitotelmata de bromeliáceas. Realizou-se uma análise cienciométrica em bases de dados virtuais sobre fitotelmata de bromeliáceas, sendo encontradas 140 publicações. A América do Sul foi a região com maior número de artigos publicados. A maioria dos artigos apresentou delineamentos preditivos, com enfoque sobre ecologia de comunidades. Insecta foi o grupo de organismos mais registrado. Investigou-se como a comunidade de microcrustáceos (composição, abundância e riqueza), associada à fitotelmata de Nidularium innocentii Lem. foi influenciada pelas variáveis limnológicas presentes ao longo do gradiente altitudinal. O estudo foi realizado na Serra da Prata, no estado do Paraná. Os resultados não apresentaram um padrão de distribuição na riqueza de espécies ao longo do gradiente altitudinal, refutando a hipótese do efeito do domínio central dentre outras. Contudo, ocorreram dissimilaridades na composição de espécies de microcrustáceos em relação às altitudes. Os diferentes tipos climáticos e de vegetações influenciaram diretamente as variáveis ambientais nos microcosmos de fitotelmata, levando à similaridades na composição de espécies entre cotas altimétricas localizadas na mesma região climática e dissimilaridades entre climas distintos.
    Description: PhD
    Keywords: Copépodes de fitotelmatas (Crustacea, Copepoda) ; Ostracoda de fitotelmatas (Crustacea, Ostracoda) ; Microcrustáceos de fitotelmatas ; Comunidades, Ecologia de ; Influências climáticas ; Bromeliaceae ; ASFA_2015::C::Crustaceans (freshwater) ; ASFA_2015::C::Climate ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 61pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 39
    facet.materialart.
    Unknown
    Gastrópodes não nativos de água doce: uma revisão sistemática global e distribuição potencial de duas espécies problemáticas. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Ecological studies in all environments of the world the effects of non-native species in various parts of the world are discussed. Regarding the invasion of these environments, we highlight the Phylum Sanitary, especially the ecological Mollusa, for presenting numerous gastronomic classes, with many species with potential, which can lead to as many sanitary, as well as sanitary and graves, in places of invasion. Know the invasive species that are reported in their scientific distribution, in this case introduction and the main ones are reported, is of fundamental importance. Knowing the risk of introducing an invasive species, and its impacts on the invaded places, it is necessary to find ways of prevention. A precious tool of meaning is an invasion of the invasive potential of one, thus generating a risk that indicates the suitability of the habitat or probability of occurrence based on the environmental conditions of the native area and the area in which the species may become invasive. . In this way, the adequacy of the invasive Melanoides tuberculata against a native species by Biomphalaria glabra, which is also a species with potential to cause toilets, is of fundamental importance, to predict possible invasion sites, and if the species are competing for the same ecological niches. Thus, the present work is subdivided into two works that address issues such as: a systematic of scientific articles about invasive freshwater gastropods. The second work will address the modeling of the current and future potential distribution of two problematic gastropod species in South America.
    Description: Estudos ecológicos em ambientes aquáticos continentais têm discutido com amplitude o efeito das espécies não nativas em várias partes do mundo. Em relação à invasão destes ambientes, destacamos o Filo Mollusca, principalmente a classe Gastropoda, por apresentar inúmeras espécies, sendo muitas destas espécies com potencial invasor, que podem levar a prejuízos tanto ecológicos, quanto econômicos e sanitários graves, em locais de invasão. Neste caso, conhecer as principais espécies invasoras que são reportadas em artigos científicos, entender sua distribuição global, seus meios de introdução e os principais danos causados, é de fundamental importância. Sabendo do risco de introdução de uma espécie invasora, e seus impactos nos locais invadidos, faz-se necessário estudos de formas de prevenção. Uma ferramenta valiosa nesse sentido é a inferência do potencial invasor de uma espécie, gerando assim um mapa de risco que indique a adequabilidade do habitat ou probabilidade de ocorrência com base nas condições ambientais da área nativa e da área em que a espécie pode vir a se tornar invasora. Deste modo, verificar adequabilidade da espécie invasora Melanoides tuberculata frente a uma espécie nativa Biomphalaria glabrata, que também é uma espécie com potencial causador de prejuízos sanitários, é de fundamental importância, para prevermos os possíveis locais de invasão, e se as espécies estão competindo pelos mesmos nichos ecológicos. Deste modo, foi efetuado uma revisão sistemática de artigos científicos a respeito de gastrópodes invasores de água doce. Em um segundo momento foi efetuado uma modelagem da distribuição potencial atual e futura de duas espécies de gastrópodes problemáticas na América do Sul.
    Description: PhD
    Keywords: Melanoides tuberculata Müller, 1774 (Gastropoda, Thiaridae) ; Gastrópodes não nativos de água doce ; Nichos ecológicos ; Invasões biológicas ; Mudanças climáticas ; Impactos ambientais ; Comunidades, Dinâmica de ; Ecologia ; Vetores de introdução ; Biomphalaria glabrata ; Efeito sanitário ; ASFA_2015::M::Molluscs (freshwater) ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::E::Ecological niches ; ASFA_2015::A::Alien species ; ASFA_2015::C::Climatic changes ; ASFA_2015::E::Environmental impact ; ASFA_2015::H::Health ; ASFA_2015::M::Mollusks (freshwater)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 72pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 40
    facet.materialart.
    Unknown
    Predizendo os efeitos do aquecimento global e de eventos climáticos extremos nas respostas funcionais e interações ecológicas do zooplâncton. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Global warming can affect thedistribution and development of organisms indirectly through changes in climate patterns and thus, in the habitat of species and, directly through the influence of high temperatures on the physiological and morphological development of organisms. These changes in thepatterns of species density, feeding and reproduction driven by warming and environmental changes also induce changes in the ecological relationships in which these organisms are involved. Thus, we investigated how these two effects of global warming, affect the performance, distribution and ecological relationships of zooplankton species, using functional responses of the organisms, such as biomass production and functional traits, in order to link these changes in zooplankton with ecosystem services. This studyis divided into three approaches, microcosm experiments controlling three temperatures, predation and competition and, a spatial and temporal approach in the upper Paraná River floodplain. In our experiments, we observed that temperature increases indeed lead to more complex relationships inside food webs, with possible negative consequences for aquatic ecosystems. However, the temperature was not the predominant factor in determining the performance of subtropical and temperate cladoceran species, as predation was the mainly structuring factor, changing the performance and competition among species. The study with the spatial and temporal approach showed that extreme climate events modify the limnological heterogeneity of shallow lakes, consequentlyaltering zooplankton species and functional traits, especially by species and traits substitution among environments (beta replacement). Factors related to predation, food availability, limnological variables and, temporal variations influenced differently the zooplankton functional beta diversity depending on the climatic event and the type of lake (connected or isolated), but limnological variables are in fact the most important factor in structuring the zooplankton distribution. Both warming and changes in climate patterns (especially intense dry seasons) negatively affected zooplankton organisms, reducing biomass production, secondary production and, the richness of functional traits among environments. The reduction of these zooplankton functional variables has negative consequences for energy stocks and, the flow of matter inside aquatic food webs, changing the ecosystem services.
    Description: O aquecimento global pode afetar a distribuição e o desenvolvimento dos organismos indiretamente através das mudanças nos padrões climáticos e, assim, no habitat das espécies, e diretamente através da influência das altas temperaturas sobre o desenvolvimento fisiológico e morfológico dos organismos. Essas mudanças nos padrões de densidade, alimentação e reprodução das espécies conduzidas pelo aquecimento e mudanças ambientais induzem também alterações nas relações ecológicas em que esses organismos estão envolvidos. Desta maneira, tivemos como objetivo investigar como esses dois efeitos do aquecimento global, afetam a performance, a distribuição e as relações ecológicas das espécies zooplanctônicas, utilizando respostas funcionais dos organismos, como a produção de biomassa e traços funcionais, com o intuito de conectar essas alterações no zooplâncton com os serviços ecossistêmicos. Para responder a este objetivo, foram realizados experimentos em microcosmos controlando três temperaturas, predação e competição; e trabalho de campo com uma abordagem espacial e temporal na planície de inundação do alto rio Paraná. Nos experimentos observou-se que o aumento de temperatura de fato leva a relações mais complexas dentro das cadeias alimentares com possíveis consequências negativas para os ecossistemas aquáticos. Porém, a temperatura não foi o fator predominante em determinar a performance das espécies de cladóceros de climas temperado e subtropical, sendo que a predação foi o fator estruturante, alterando a performance e as relações de competição entre as espécies. Por meio da abordagem espacial e temporal, observou-se que os eventos climáticos extremos alteram a heterogeneidade limnológica dos lagos rasos com consequente alteração das espécies e dos traços funcionais do zooplâncton, especialmente por meio da substituição de espécies e traços entre os ambientes (beta replacement). Os fatores relacionados a predação, disponibilidade de alimento, variáveis limnológicas e as variações temporais influenciaram diferentemente a diversidade beta funcional do zooplâncton dependendo do evento climático e do tipo de lagoa (conectada ou isolada), mas,de fato as variáveis limnológicas foram o fator mais importante em estruturar a distribuição do zooplâncton. Tanto o aquecimento quanto as mudanças nos padrões climáticos (especialmente períodos de secas intensas) afetaram negativamente os organismos zooplanctônicos, com redução na produção de biomassa, na produção secundária, e na riqueza de traços funcionais entre os ambientes. A redução dessas variáveis funcionais do zooplâncton tem consequências negativas para os estoques de energia e para o fluxo de matéria dentro das cadeias alimentares aquáticas, com alterações nos serviços ecossistêmicos.
    Description: PhD
    Keywords: Zooplâncton de água doce ; Comunidades, Ecologia de ; Competição ; Diversidade funcional ; Mudanças climáticas ; La Niña e El Niño ; Predação ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::Y::Zooplankton ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::C::Climatic changes ; ASFA_2015::F::Floodplains ; ASFA_2015::P::Predation ; ASFA_2015::C::Competition
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 122pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 41
    facet.materialart.
    Unknown
    Relação da influência antropogênica e da complexidade de habitat sobre a diversidade funcional da ictiofauna em um reservatório Neotropical. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Reservoirs shores are usually colonized by submerged macrophytes, which have a high influence over the functional diversity of fish assemblages. However, there are also intense anthropogenic activities in these habitats, which may affect the functional structure of fish communities as well. Thus, aiming to evaluate the influence of anthropogenic activities and habitat complexity, provided by submerged macrophytes, on the functional diversity of the ichthyofauna of reservoirs, sampling was carried out in three sites in the marginal areas of the Itaipu reservoir, in places near and apart artificial beaches, with and without submerged macrophytes. Functional traits used were morphometric measurements taken from the sampled individuals (intraspecific traits), which were used to calculate three functional diversity indexes: functional richness, evenness and divergence. In general, we found no patterns in functional diversity indexes regarding the distance from artificial beaches (among sampling stations). In contrast, habitat complexity influenced the functional diversity of fish assemblages, which presented different results depending on macrophytes density. While functional richness increased in higher complexities, the opposite occurred considering functional evenness. Additionally, functional divergence was higher in regions without macrophytes. In conclusion, this study improves the knowledge on the importance of different habitats in the maintenance of the functional diversity of fishes in habitats of reservoirs shores, supporting the implementation of management and conservation strategies in these environments.
    Description: Regiões litorâneas de reservatórios são normalmente colonizadas por bancos de macrófitas submersas, que possuem elevada influência sobre a diversidade funcional das assembleias aquáticas, inclusive peixes. Apesar disso, esses habitats apresentam alta influência antropogênica, o que também pode afetar a estruturação funcional de comunidades aquáticas. Portanto, para avaliar a influência das atividades antropogênicas e da complexidade de habitat, proporcionada pelas macrófitas, sobre a diversidade funcional da ictiofauna, foram amostrados três braços do reservatório de Itaipu, em regiões de praias artificiais e em locais afastados destas áreas (não praia), considerando a presença e ausência de macrófitas submersas. Traços funcionais derivados de variáveis morfométricas foram usados para o cálculo dos índices de riqueza, equitabilidade e divergência funcional, que incorporaram a variação intraespecífica das assembleias amostradas. Em geral, não houveram diferenças nos índices de diversidade funcional em função da proximidade de praias artificiais. Em contraste, a complexidade de habitat influenciou a diversidade funcional da ictiofauna e as respostas dos índices dependeram da densidade de macrófitas. Enquanto a riqueza funcional aumentou em maiores complexidades, foi observado o inverso em relação a equitabilidade funcional. Por fim, a divergência funcional foi maior em regiões de margem, sem macrófitas submersas. Por meio dos padrões identificados, esse trabalho contribui com o conhecimento sobre a importância dos diferentes habitats para a diversificação funcional das espécies de peixes em regiões litorâneas nos braços de reservatórios, com estrutura decorrente de macrófitas submersas, servindo como base para implementação de estratégias de manejo e conservação nestes ambientes.
    Description: Masters
    Keywords: Peixes de água doce, Assembléia de ; Ecologia de reservatórios ; Diversidade funcional ; Habitat ; Complexidade estrutural ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::A::Assemblages ; ASFA_2015::R::Reservoirs (water) ; ASFA_2015::H::Habitat ; ASFA_2015::B::Biodiversity ; ASFA_2015::M::Macrophytes
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 42pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 42
    facet.materialart.
    Unknown
    A biomassa de macrófita como mediadora da relação entre peixes congêneres e invertebrados. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: In the study it was verified if the habitat complexity, assessed through macrophyte biomass, can mediate the interaction between fish and invertebrates, and help to explain the coexistence of congeneric species. Fish and invertebrates were sampled in ten macrophytes stand with different biomasses in upper Paraná River floodplain. The abundance and richness of invertebrates, the diet and the niche breadth of Moenkhausia bonita and Moenkhausia forestii were evaluated, as well as the overlap of the diet between the congeneric species. With the increase in macrophyte biomass, there was an increase in the abundance of invertebrates, however, the richness did not show a significant influence from the biomass. The diet of both species differed between macrophytes stands with different biomasses, the main difference being the decrease in invertebrate consumption, mainly aquatic, and the increase in consumption of plants. In addition, the consumption of the items proved to be dependent on their profitability and accessibility in the environment. The niche breadth of both species increased with the increase in macrophyte biomass, but there was no overlap of the niche between them. The results showed that although there was an increase in the invertebrate abundance, there was a decrease in the consumption of this resource, indicating that more complex stands can be more effective refuges for aquatic invertebrates. These results reveal the role of habitat complexity in mediating the interaction between fish and invertebrates, promoting coexistence between them, which helps to explain also the coexistence of ecologically similar fish species.
    Description: Neste estudo verificou-se se a complexidade do habitat, avaliada por meio da biomassa de macrófitas, pode mediar a interação entre peixes e invertebrados, e ajudar a explicar a coexistência de espécies congêneres. Peixes e invertebrados foram amostrados em dez bancos de macrófitas com diferentes biomassas na planície de inundação do alto rio Paraná. Foram avaliadas a abundância e a riqueza de invertebrados, a dieta e a amplitude do nicho de Moenkhausia bonita e de Moenkhausia forestii, assim como a sobreposição da dieta entre as espécies. Com o incremento da biomassa de macrófitas houve uma ampliação na abundância de invertebrados, porém a riqueza não mostrou uma relação significativa com a biomassa. A dieta de ambas as espécies diferiu entre os bancos, tendo um decréscimo no consumo de invertebrados, principalmente aquáticos, e incremento no consumo de vegetal com o aumento da biomassa. Ademais, o consumo dos itens mostrou-se dependente da rentabilidade e acessibilidade deles no ambiente. A amplitude do nicho de ambas as espécies aumentou conforme houve um incremento na biomassa de macrófitas, porém não houve sobreposição do nicho entre elas. Os resultados mostraram que embora tenha ocorrido aumento na abundância de invertebrados, houve um decréscimo no consumo deste recurso, indicando que bancos com maior complexidade podem ser refúgios mais efetivos para os invertebrados aquáticos. Estes resultados indicaram o papel da complexidade do habitat em mediar a interação entre peixes e invertebrados, promovendo a coexistência entre eles, assim como a coexistência das espécies de peixes ecologicamente similares.
    Description: Masters
    Keywords: Ecologia trófica ; Ecologia de rio ; Forrageamento ótimo, Teoria do ; Relação peixe-macrófita ; Habitat ; Complexidade estrutural ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::F::Freshwater fish ; ASFA_2015::B::Biomass ; ASFA_2015::P::Predators ; ASFA_2015::P::Prey ; ASFA_2015::T::Trophic relationships ; ASFA_2015::F::Floodplains ; ASFA_2015::A::Associations (ecological)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 37pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 43
    facet.materialart.
    Unknown
    Relação entre a complexidade estrutural de macrófitas e os atributos da assembleia de peixes em um reservatório Neotropical. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Habitat complexity is one of the main factors determining biological diversity and its assessment is a challenge that involves several variables. Submerged macrophytes are responsible for changes in habitat complexity and may enhance habitat conditions for different species. These plants usually colonize natural and artificial lentic environments, such as reservoirs, which have abiotic characteristics favorable to their establishment. The construction of the Itaipu Dam and the filling of the reservoir favored the establishment of macrophytes due to changes in flow dynamics. Therefore, the aim of this work was to evaluate whether habitat complexity, provided by macrophytes, is associated with changes in fish assemblage attributes (abundance, richness, and evenness) and composition. Linear regression models were applied to test the relationship between abundance, richness, and evenness with habitat complexity (expressed as macrophyte density - g/m²). In addition, Principal Coordinates Analysis (PCoA) and Spearman correlations were used to assess changes in the composition of fish assemblages according to macrophytes density. The results indicate a direct relationship between habitat complexity and fish assemblage attributes as well as associations between macrophyte density and fish assemblage composition, improving the knowledge about species preference for different levels of complexity. Thus, it is important to consider the behavior of species known to cause economic and ecological issues for future management and conservation efforts.
    Description: A complexidade de habitat é um dos fatores determinantes para a manutenção da diversidade biológica e, avaliar sua influência, é um desafio que envolve muitas variáveis. As macrófitas submersas são responsáveis por alterar a complexidade dos habitats, podendo promover melhores condições de habitat para um maior número de espécies. Essas plantas geralmente colonizam ambientes lênticos naturais e, também, artificiais, como reservatórios, que possuem características abióticas favoráveis ao seu crescimento. A construção do reservatório de Itaipu favoreceu a proliferação de macrófitas devido às alterações na dinâmica da água. Avaliou-se a complexidade de habitat, proporcionada pelas macrófitas, está associada com mudanças nos atributos (abundância, riqueza e equitabilidade) e na composição da assembleia de peixes do reservatório de Itaipu. Foram utilizadas regressões lineares para verificar a relação entre a abundância, riqueza e equitabilidade com a complexidade de habitat (representada pela densidade de macrófitas - g/m²). Na sequência uma Análise de Coordenadas Principais (PCoA) e correlações de Spearman foram utilizadas para avaliaras alterações na composição das assembleias de acordo com a densidade de macrófitas. Houve relação direta entre a complexidade de habitat e os atributos das assembleias. Também foi possível identificar relações entre a densidade de macrófitas com a composição das assembleias, contribuindo com conhecimento relacionado à preferência de espécies por ambientes com determinados níveis de complexidade. Dessa forma, é importante considerar o comportamento de algumas dessas espécies, conhecidas por causarem prejuízos econômicos e ecológicos aos locais, para as ações de manejo e conservação futuras.
    Description: Masters
    Keywords: Peixes de água doce ; Macrófitas aquáticas submersas ; Assembleia ; Interação peixe-planta ; Complexidade estrutural ; Reservatórios ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::A::Assemblages ; ASFA_2015::I::Interactions ; ASFA_2015::R::Reservoirs (water)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 39pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 44
    facet.materialart.
    Unknown
    Revisão taxonômica de Cambeva stawiarski (Miranda Ribeiro, 1968) (Siluriformes, Trichomycteridae) com a descrição de uma nova espécie da bacia do Rio Iguaçu, estado do Paraná, Brazil. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: The objective was to redescribe Cambeva stawiarski, using internal morphological data, external morphology, morphometry and meristic data, through the revision of the type-material and material deposited in fish collections. In this process, we have also added comments on the possible Cambeva stawiarski type-locality and described a new species of Cambeva, endemic to the Rio Iguaçu basin, Brazil. Cambeva stawiarski and the new species are diagnosed by the number of procurrent caudal-fin rays dorsally and ventrally; number of vertebrae; number of pectoral-fin rays; number of branchiostegal rays; small notch on the distal margin of the caudal-fin; head length; caudal peduncle depth; and the colouration pattern of the body. In addition, the species are compared with other possibly related species and the synapomorphic characters of these groups of species are discussed. With confirmation of the endemism of Cambeva stawiaski and the description of a new species of Cambeva for the Rio Iguaçu basin, we confirm important biogeographic patterns on the endemism of this hydrographic basin and in the use of osteological data in the description of Cambeva species
    Description: O objetivo foi redescrever Cambeva stawiarski, com base em dados morfológicos internos, morfologia externa, morfometria e dados merísticos, por meio da revisão do material tipo e de material depositado em coleções ictiológicas. Neste processo, fora acrescentado comentários sobre a possível localidade-tipo de Cambeva stawiarski e descreveu-se uma nova espécie de Cambeva, endêmica da bacia do rio Iguaçu, Brasil. Cambeva stawiarski e a nova espécie são diagnosticadas pela combinação de caracteres como número de raios procurrentes caudais dorsais e ventrais; número de vértebras; número de raios na nadadeira peitoral; número de raios branquiostegais; nadadeira caudal com pequeno entalhe na margem distal; comprimento da cabeça; altura do pedúnculo caudal; e padrão de colorido do corpo. As espécies também são comparadas com outras espécies possivelmente relacionadas e os caracteres sinapomórficos desses grupos de espécies são discutidos. Com a confirmação do endemismo de Cambeva stawiarski e a descrição de uma nova espécie de Cambeva para a bacia do rio Iguaçu, confirmamos importantes padrões biogeográficos sobre o endemismo da bacia hidrográfica e sobre a utilização de dados osteológicos na descrição de espécies de Cambeva.
    Description: Masters
    Keywords: Cambeva stawiarski (Miranda Ribeiro, 1968) (Siluriformes, Trichomycteridae) “candiru” ; Taxonomia ; ASFA_2015::F::Freshwater fish ; ASFA_2015::T::Taxonomy ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Morphology (animal)
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 59pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 45
    facet.materialart.
    Unknown
    A diversidade, a luminosidade e a turbidez determinam locais ecologicamente únicos para comunidade de algas e cianobactérias em microecossistemas naturais de água doce. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Partitioning patterns of dissimilarity (beta diversity) into contributions of single sites or individual species is a modern approach to understanding what the main factors affect and cause variation in biodiversity. In this context, estimating the contributions of single sites to overall beta diversity (LCBD) or into contributions of individual species to overall beta diversity (SCBD) has proven to be a good approach to improve the knowledge of drivers of beta diversity. We explored the contributions of each site and species to the overall algae and cyanobacteria beta diversity of 77 natural freshwater micro-ecosystems (i.e., tank bromeliads) of a neotropical ecosystem. We found that LCBD was negatively affected by Shannon's diversity, turbidity, and luminosity (% canopy cover). Cyanobacteria and green algae were the groups that most contributed SCBD values. The negative relationship between LCBD and the Shannon index indicates that micro-ecosystems with less diversity reflect unique characteristics, and LCBD values can easily predict these environments. LCBD values can indicate these environments as priorities for management and conservation.
    Description: Particionar padrões de dissimilaridade (diversidade beta) em contribuições dos locais ou de espécies é uma abordagem moderna para compreender quais os principais fatores afetam e provocam variação na biodiversidade. Neste contexto, estimar a contribuição local para o pool regional de espécies (LCBD) e a contribuição de cada espécies para a diversidade beta (SCBD) tem se mostrado uma eficiente abordagem para inferir sobre mecanismos condutores da diversidade beta. Nesse estudo foram exploradas as contribuições de cada local e espécies para a diversidade beta total de algas e cianobactérias de 77 microecossistemas naturais de água doce (i.e., bromélias-tanque) de um ecossistema neotropical. A LCBD foi afetada negativamente pela diversidade de Shannon, turbidez e luminosidade (% cobertura de dossel) A relação negativa do LCBD com o índice de Shannon indica que locais menos diversos podem refletir em ambientes com características específicas. Cianobactérias e fitoflagelados apresentaram maior contribuição para os valores de SCBD. A compreensão da influência do LCBD e SCBD na distribuição dos padrões da diversidade beta podem facilmente prever esses ambientes com características singulares, fazendo dos mesmos prioritários para práticas de manejo e conservação.
    Description: Masters
    Keywords: Fitoplâncton de água doce ; Comunidades, Ecologia de ; Determinantes ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::P::Phytoplankton ; ASFA_2015::A::Algae ; ASFA_2015::B::Biodiversity ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::I::Islands
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 50pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 46
    facet.materialart.
    Unknown
    Padrões de distribuição espacial das assembleias de peixes em reservatórios neotropicais. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Given the great diversity of Neotropical fish species, as well as the importance of such organisms as a link within aquatic food chains, it is essential to assess different processes that drive the spatial organization of their communities. It is known that the structure of fish assemblages varies markedly in relation to space, depending on abiotic factors, biotic interactions, and dispersion processes. However, these determining factors in the structuring of fish communities vary indiscriminately in dammed aquatic bodies. The course of large rivers has been altered due to the construction of reservoirs and the number of projects under construction or inventoried has been increasing significantly in recent decades. Therefore, evaluating how the spatial organization of fish assemblages occurs in environments (i.e., dammed), as well as unraveling the predictors associated with this organization is of extremely important for conservation purposes and the implementation of management measures. To investigate such aspects in dammed environments, in the first study three cascades of reservoirs belonging to different hydrographic basins were studied, in which the effects of these reservoirs arranged in series on the patterns of diversity, distribution and richness of the assemblages were evaluated. In the second study, 29 reservoirs located in the state of Parana were evaluated in order to identify relationships between the organization of fish trophic guilds and environmental, spatial and morphological predictors. The results found suggest that, in most of the studied environments, the environmental changes caused by the construction of dams, as well as their morphological characteristics and modes of operation have negative effects on the diversity, distribution and abundance of fish species and exert an influence on the different fish trophic guilds.
    Description: Dada a grande diversidade de espécies de peixes contidas na região Neotropical, bem como a importância desses organismos como elo nas cadeias tróficas aquáticas, se faz necessário conhecer os distintos processos que governam a organização espacial de suas comunidades. Sabe-se que a estrutura das assembleias de peixes varia acentuadamente em relação ao espaço a depender de fatores abióticos, interações bióticas e processos de dispersão. Entretanto, esses fatores determinantes na estruturação das comunidades de peixes variam indiscriminadamente em corpos aquáticos barrados. O curso de grandes rios tem sido alterado devido a construção de reservatórios e o numero de empreendimentos em construção ou inventariados vem aumentando significativamente nas ultimas décadas. Portanto, avaliar como ocorre a organização espacial das assembleias de peixes nesses ambientes (i.e., barrados), bem como desvendar os preditores associados a essa organização e de extrema importância para fins conservacionistas e implementações de medidas de manejo. Para investigar tais aspectos, na primeira abordagem foram estudadas três cascatas de reservatórios pertencentes a diferentes bacias hidrográficas, para avaliar os efeitos da disposição em serie dos reservatórios nos padrões de diversidade, distribuição e riqueza das assembleias de peixes. Na segunda abordagem, foram avaliados 29 reservatórios situados no estado do Paraná com o objetivo de identificar relações entre a organização das guildas tróficas de peixes com preditores ambientais, espaciais e morfológicos. Os resultados encontrados pelas duas abordagens sugerem que, na maioria dos reservatórios estudados, as alterações ambientais provocadas devido a construção de barragens, bem como suas características morfológicas e modos de operação tem efeitos negativos sobre a diversidade, distribuição e abundancia das espécies de peixes e exercem influencia sobre as diferentes guildas tróficas de peixes.
    Description: PhD
    Keywords: Peixes de água doce ; Assembleia ; Guildas tróficas ; Cascata de reservatórios ; Padrões de distribuição ; Cascata de reservatórios Neotropicais ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Assemblages ; ASFA_2015::T::Trophic levels ; ASFA_2015::R::Reservoirs (water) ; ASFA_2015::F::Food chains ; ASFA_2015::D::Distribution ; ASFA_2015::S::Spatial distribution
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 153pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 47
    facet.materialart.
    Unknown
    Efeitos de diferentes intensidades de ocupação aquícola sobre a estrutura taxonômica e funcional de assembleias de peixes em riachos Neotropicais. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-29
    Description: Biological invasion processes are complex phenomena and comprise one of the greatest challenges for the conservation of biodiversity in continental aquatic environments. The pressure of propagules, i.e., the number of non-native individuals released and the number of release events, is among the different mechanisms involved in these decisive processes for the successful establishment of non-native species. In this scenario, aquaculture is an important source of propagules of species with high invasive potential, such as Nile Tilapia (Oreochromis niloticus), as accidental escapes and intentional releases from production ponds are recurrent. Nine small streams, tributaries of the Piquiri River (Paraná, Brazil), were sampled to evaluate the effect of aquaculture on fish assemblages in neotropical streams. The watersheds of these streams differ in percentage of aquaculture occupation, and this difference was used as a proxy for propagule pressure of O. niloticus in natural environments. Therefore, the present research aimed to evaluate the effects of different intensities of aquaculture production of tilapia on the richness patterns, composition and structure of the ichthyofauna, testing the hypothesis that the increase in propagule pressure of this species alters the patterns of occurrence and abundance of assemblages, as well as discuss the effects of this species on the functional structure of ichthyofauna, observing the effect of aquaculture occupation on responses of functional diversity indexes and on dissimilarity patterns among the different streams. The results indicated that streams with no aquaculture occupation and with no presence of O. Niloticus had more similar compositions and differed in patterns of occurrence and distribution of ichthyofauna from streams under aquaculture activity. In addition, the presence of tilapia altered the functional diversity indexes in the streams, as the species presented more extreme traits that allow it to increase the functional space of receptor environments and promote greater niche differentiation. The results reinforce the potential of aquaculture as an important source of propagules of non-native species for natural environments and raise attention to the structuring power of tilapia on the taxonomic and functional composition of native ichthyofauna.
    Description: Os processos de invasão biológica são fenômenos complexos e compreendem um dos maiores desafios para a conservação da biodiversidade em ambientes aquáticoscontinentais. Dentre os diferentes mecanismos envolvidos nesses processos, a pressão de propágulos, isto é, o número de indivíduos não nativos liberados e o número de eventos de liberação são determinantes no sucesso de estabelecimento de espécies não nativas. Neste cenário, a aquicultura se insere como uma importante fonte de propágulos de espécies com alto potencial invasor, a exemplo da Tilápia do Nilo, Oreochromis niloticus, uma vez que os escapes acidentais e as solturas intencionais dos tanques de produção são recorrentes. A fim de avaliar a influênciada aquiculturasobre as assembleias de peixes em riachos Neotropicais, nove riachos de pequena ordem,afluentes do rio Piquiriforam amostrados. Estes riachosdiferem quanto a porcentagem de ocupação aquícola emsuas microbacias, sendo essa diferença utilizada como um proxyda pressão de propágulos de O. niloticuspara ambientes naturais. Sendo assim, a presente pesquisa teve como objetivosavaliar os efeitos de diferentes intensidades deprodução aquícolada tilápiasobre os padrões de riqueza,composição eestrutura da ictiofauna, testando-se a hipótese de que o aumento da pressão de propágulos dessa espécie alteraos padrões deocorrência e deabundância das assembleias, bem comodiscutir os efeitosdessa mesma espécie sobre a estrutura funcional da ictiofauna, observando-se a influência da ocupação aquícola nas respostas dos índices de diversidade funcional e nos padrões de dissimilaridade entre os diferentes riachos. Os resultados indicaramqueriachos sem ocupação aquícola e sem a presença deO. niloticusforammais similares em suas composiçõese diferiramnospadrões de ocorrência e distribuição da ictiofauna dos riachos com atividade aquícola. Observou-se também a presença da espécie alterou os índices de diversidade funcional entre os riachos, por apresentar traços mais extremos que lhe permitem aumentar o espaço funcional dos ambientes receptores e promover maior diferenciação de nicho. Os resultados reforçam o potencial da aquicultura como uma fonte importante de propágulos de espécies não nativas para ambientes naturais e atentam para o poder estruturador da tilápia sobre a composição taxonômica e funcional da ictiofauna nativa.
    Description: PhD
    Keywords: Peixes de riachos, Assembleia de ; Peixes de água doce ; Oreochromis niloticus (Linnaeus, 1758) ; Bioinvasões ; Invasões biológicas ; Potencial invasor ; Composição taxonômica e funcional ; Ecologia ; Impactos ; Produção aquícola ; Pressão de Propágulos ; Piscicultura ; Tanques escavados ; Escapes e solturas ; Ocupação aquícola ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Aquaculture ; ASFA_2015::A::Assemblages ; ASFA_2015::S::Streams ; ASFA_2015::I::Ichthyofauna ; ASFA_2015::A::Alien species ; ASFA_2015::F::Fish ponds ; ASFA_2015::E::Environmental impact ; ASFA_2015::R::Release mechanisms ; ASFA_2015::P::Pisciculture ; ASFA_2015::T::Taxonomy
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 79pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 48
    facet.materialart.
    Unknown
    Preditores ecológicos de múltiplas facetas da diversidade beta usando grupos biológicos díspares e diferentes níveis taxonômicos em escalas espaciais e temporais hierárquicas. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-12
    Description: Our knowledge on temporal and fine- and broad-scale patterns of biodiversity, as a basis for biogeographical models and conservation planning, have been few explored to two fundamental components of beta diversity: replacement and richness difference. Whether variability in these components of beta diversity is congruent in space and time for disparate biological groups, which show wide variation in functional traits (e.g., dispersal mode), is, hitherto, unknown. Moreover, one of the main standing paradigms is to understand whether the empirical biogeographic patterns of macro-organisms also apply to micro-organisms. This thesis consists of three papers. The first one aimed to determine whether the cross-taxon congruence of taxonomic and functional beta diversity and its components varies across space, and time. Our results showed how detailed hierarchical analyses can reveal hidden patterns of cross-taxon congruence. We partly supported the hypothesis that the strength of cross-taxon congruence generally decreases with the increase of functional distances between pairs of biological groups. In the second paper, we contrasted longitudinal patterns in the total beta diversity and its components in the last non-dammed stretch of the Paraná River for actively (fish) and passively (phytoplankton) dispersing biological groups. The results ratify that biodiversity patterns exhibited by single biological groups do not necessarily match those of other groups that show wide variation in biological features. Our findings have improved understanding of tributary-induced heterogeneity and highlight the importance of dam-free stretches of rivers for preserving its integrity. In the third paper, we used morphological data from live organisms and molecular data to verify which approach better explain the role of environmental and spatial predictors on the ciliates structuration, as well as clarify their biogeography. We found that environmental filters had a greater influence on the morphological than on the molecular site-by-site dissimilarities. Meanwhile, biogeographic factors and the distance among sites limit the distribution of molecular-based composition, resulting in significantly different species compositions in each of the floodplain-associated lakes analyzed. In summary, the findings of this thesis suggest that conservation biology and environmental assessment need to monitor different biological groups, as well as take into account for the choice of taxonomic resolution, as each group and approach provides unique insights.
    Description: O conhecimento sobre padrões temporais e espaciais locais e regionais da biodiversidade, como base para modelos biogeográficos e planejamento de conservação, foi pouco explorado para dois componentes fundamentais da diversidade beta: substituição e diferença de riqueza. Avaliar até que ponto a variabilidade nesses componentes da diversidade beta é congruente no espaço e no tempo para grupos biológicos distintos, que possuem ampla variação em suas características funcionais (por exemplo, modo de dispersão) é, até agora, desconhecido. Ademais, um dos principais paradigmas da ecologia é entender se os padrões biogeográficos empíricos dos macrorganismos também se aplicam aos microrganismos. Assim, esta tese é composta por três segmentos. O primeiro teve como objetivo determinar se a congruência entre táxons da diversidade beta taxonômica e funcional e seus componentes variam ao longo do espaço e do tempo. Os resultados mostraram como análises hierárquicas detalhadas podem revelar padrões ocultos de congruência entre táxons. Foi apoiada parcialmente a hipótese de que a força da congruência entre táxons geralmente diminui com o aumento das distâncias funcionais entre pares de grupos biológicos. No segundo segmento, foram contrastados padrões longitudinais na diversidade beta total e seus componentes no último trecho não represado do rio Paraná para grupos biológicos de dispersão ativa (peixe) e passiva (fitoplâncton). Os resultados ratificam que os padrões de biodiversidade exibidos por grupos biológicos únicos não coincidem necessariamente com os de outros grupos que mostram grande variação nas características biológicas. Estas descobertas melhoram a compreensão da heterogeneidade induzida por tributários e destacam a importância dos trechos de rios livre de barramentos para preservar sua integridade. No terceiro segmento, foram utilizados dados morfológicos de organismos vivos e dados moleculares para verificar qual abordagem explica melhor o papel dos preditores ambientais e espaciais na estruturação de protistas ciliados, bem como tentar esclarecer sua biogeografia. Foi demonstrado que os filtros ambientais tiveram uma maior influência na dissimilaridade par a par baseada em dados morfológicos do que nas baseadas em dados moleculares. Entretanto, fatores biogeográficos, impostos pela distância entre os locais, limitam a distribuição da composição baseada em dados moleculares, resultando em composições de espécies significativamente distintas em cada um dos lagos associados às planícies de inundação analisadas. Em resumo, os resultados desta tese demonstram que a biologia da conservação e a avaliação ambiental precisam monitorar diferentes grupos biológicos, bem como levar em consideração a escolha da resolução taxonômica, pois cada grupo e abordagem fornecem insights exclusivos.
    Description: PhD
    Keywords: Comunidades, Ecologia de ; Ecologia de água doce ; Biodiversidade ; Dispersão ; Biologia da conservação ; Padrões biogeográficos ; Sistema rio-planície de inundação ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::B::Biodiversity ; ASFA_2015::C::Conservation ; ASFA_2015::D::Dispersion ; ASFA_2015::F::Floodplains ; ASFA_2015::R::Rivers ; ASFA_2015::B::Biogeography
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 159pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 49
    facet.materialart.
    Unknown
    The climatological rise in winter temperature- and dewpoint-based thaw events and their impact on snow depth on Mount Washington, New Hampshire (2022)
    American Meteorological Society
    Details
    Publication Date: 2022-06-06
    Description: Author Posting. © American Meteorological Society, 2021. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Applied Meteorology and Climatology 60(9), (2021): 1361–1370, https://doi.org/10.1175/JAMC-D-20-0254.1.
    Description: We analyze how winter thaw events (TE; T 〉 0°C) are changing on the summit of Mount Washington, New Hampshire, using three metrics: the number of TE, number of thaw hours, and number of thaw degree-hours for temperature and dewpoint for winters from 1935/36 to 2019/20. The impact of temperature-only TE and dewpoint TE on snow depth are compared to quantify the different impacts of sensible-only heating and sensible-and-latent heating, respectively. Results reveal that temperature and dewpoint TE for all metrics increased at a statistically significant rate (p 〈 0.05) over the full time periods studied for temperature (1935/36–2019/20) and dewpoint (1939/40–2019/20). Notably, around 2000/01, the positive trends increased for most variables, including dewpoint-thaw degree-hours that increased by 82.11 degree-hours decade−1 during 2000–20, which is approximately 5 times as faster as the 1939–2020 rate of 17.70 degree-hours decade−1. Furthermore, a clear upward shift occurred around 1990 in the lowest winter values of thaw hours and thaw degree-hours—winters now have a higher baseline amount of thaw than before 1990. Snow-depth loss during dewpoint TE (0.36 cm h−1) occurred more than 2 times as fast as temperature-only TE (0.14 cm h−1). With winters projected to warm throughout the twenty-first century in the northeastern United States, it is expected that the trends in winter thaw events, and the sensible and latent energy that they bring, will continue to rise and lead to more frequent winter flooding, fewer days of good quality snow for winter recreation, and changes in ecosystem function.
    Keywords: Atmosphere ; Snowmelt/icemelt ; Snowpack ; Winter/cool season ; Climate change ; Humidity ; Latent heating/cooling ; Snow cover ; Temperature
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 50
    facet.materialart.
    Unknown
    Mudanças globais: avaliando as interações entre CO2, eutrofização e espécies não nativas em ecossistemas aquáticos continentais. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-18
    Description: Ecosystems respond to the direct, indirect and synergistic effects of global changes caused by human activity. The understanding of the impacts of these changes and especially of the interaction between the impacts is still limited, especially for aquatic environments, because the interaction between them is rarely considered in environmental studies and assessments. We conducted a systematic literature review on the combination of the factors (i) increase of CO2, (ii) eutrophication and (iii) non-native species to verify how these factors have been considered in the context of climate change in freshwater ecosystems studies. Through the Web of Science database, we searched for articles published in English, up to 2020. Following the PRISMA protocol, 62 articles were analyzed. Only 8% of them addressed the combination of the three factors, among them, eutrophication was the most evaluated global change. Still, the studies do not seem to be looking for answers in a broad way and covering several ecological aspects, since they are concentrated in specific regions such as the Netherlands and United States (44%). Studies most focus on one type of environment, the lentic; use organisms from the base of the food-web; apply the experimental approach; evaluate one organizational level (community) and one response variable (biomass). We identified that the effect of the combination of factors is rarely classified with the terms synergistic and antagonist, even when the authors find these patterns. Our main findings reveal that little attention has been given to the combination of factors in freshwater ecosystems. We also find that when interactions are considered, non-native species tend to be favored and algal blooms intensified (74%). Considering that one of the major challenges is to understand how the interaction between global change factors will affect ecosystems, the combinations of factors still need to be prioritized in studies of aquatic ecosystems.
    Description: Os ecossistemas respondem aos efeitos diretos, indiretos e sinérgicos das mudanças globais causadas pela atividade humana. A compreensão sobre os impactos dessas mudanças e principalmente da interação entres os impactos ainda é limitada, especialmente para os ambientes aquáticos, pois raramente a interação entre eles é considerada nos estudos e avaliações ambientais. Realizou-se uma revisão sistemática da literatura para verificar como a combinação dos fatores: (i) aumento da concentração de CO2, (ii) eutrofização, e (iii) espécies não nativas, está sendo abordada no contexto de mudanças globais em ecossistemas aquáticos continentais. Por meio da plataforma Web of Science, procurou-se por artigos publicados em inglês, até 2020. Seguindo o protocolo PRISMA, 62 artigos foram analisados. Apenas 8% dos estudos abordaram a combinação dos três fatores, dentre eles, a eutrofização foi o fator de mudança global mais avaliado. Ainda, os estudos não parecem estar buscando respostas de forma ampla e abrangendo diversos aspectos ecológicos, visto que, se concentram em regiões específicas, na Holanda e nos Estados Unidos (44%), focam em ambientes lênticos; utilizam majoritariamente organismos da base da cadeia trófica; são em sua maioria experimentais; e avaliam um nível organizacional (comunidade) e uma variável resposta (biomassa). Raramente o efeito da combinação dos fatores é classificado com os termos sinérgico e antagônico, mesmo quando os autores encontram esses padrões. Como resultados principais evidenciou-se que pouca atenção tem sido dada à combinação dos fatores nos ecossistemas aquáticos continentais. Os estudos analisados mostraram que quando consideradas as interações, espécies não nativas tendem a ser favorecidas e florações algais intensificadas (74%). Considerando que um dos maiores desafios atuais é compreender como a interação entre fatores de mudanças globais afetará os ecossistemas, a combinação de fatores ainda precisa ser priorizada nos estudos dos ecossistemas aquáticos.
    Description: Masters
    Keywords: Ecossistemas de água doce ; Ambientes aquáticos continentais ; Mudanças globais ; Múltiplos fatores ; Efeitos da ação do homem ; Impactos ambientais sinérgicos ; Revisão de literatura ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::E::Ecosystems ; ASFA_2015::C::Climatic changes ; ASFA_2015::E::Eutrophication ; ASFA_2015::A::Alien species ; ASFA_2015::L::Literature reviews
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 42pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 51
    facet.materialart.
    Unknown
    Impactos da mudança climática sobre ostrácodes de água doce (Crustacea, Ostracoda). (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-04
    Description: Species are exposed to natural climate change throughout their evolutionary history. However, anomalous global warming and resulting variations in rainfall patterns affect survival, alter the distribution of organisms and the network of species interactions. The aim of this thesis was to find larger-scale (basin and biome level) patterns for the possible effects of climate change on the distribution of South American freshwater ostracods through ensemble analysis of several species-distribution modelling algorithms. Here, climate change was based on two assumptions of increasing carbon emissions, the moderate-optimistic (RCP 4.5) and pessimistic (RCP 8.5) scenarios of four climate models (AOGCMs), from 2050 and 2080. In the first approach, projections of changes in ostracod species richness and composition were presented, and conservation status of 61 species from 13 river basins in the Southern Cone. In the second approach, the geographical pattern of a symbiotic interspecific interaction of commensalism type was evaluated through the climatic suitability of Elpidium (Ostracoda) and tank bromeliads of the Atlantic Forest, and the availability of habitat for Elpidium (presence of tank bromeliads) in the future. For both approaches, climate change directly influenced the decrease in future distribution areas of ostracods. The results of the first approach showed a decrease in ostracod richness in the Southern Cone basins of South America, and different species compositions in 2050 and 2080, in both the moderate-optimistic and pessimistic scenarios. The decrease in the ranges of ostracods will change the conservation status of several species to “potentially threatened”. Elpidium ranges will be more limited in the future, and there will be less habitat availability, i.e. fewer tank bromeliad species for interaction. In general, precipitation and temperature regimes are synchronized with phenological life-history events of the species, which determine the direction of dispersal to the environmental set of optimal survival conditions in the future. Our results contribute to the inclusion of ostracods (and other invertebrates) in conservation plans for their habitats on larger geographical scales.
    Description: Espécies estão expostas às mudanças climáticas naturais ao longo de sua história evolutiva, entretanto o aquecimento global anômalo e as variações resultantes nos padrões pluviométricos afetam a sobrevivência, alteram a distribuição dos organismos e a rede de interações das espécies. O objetivo desta tese foi encontrar padrões em maior escala (nível de bacia e bioma) dos possíveis efeitos da mudança climática sobre a distribuição de ostrácodes de água doce da América do Sul, através de análise conjunta de diversos algoritmos de modelagem de distribuição de espécies. A mudança climática foi baseada em duas hipóteses de aumento das emissões de carbono, os cenários moderado-otimista (RCP 4.5) e pessimista (RCP 8.5) de quatro modelos climáticos (AOGCMs) de 2050 e 2080. Na primeira abordagem foram apresentadas projeções de mudanças na riqueza e composição de espécies de ostrácodes e status de conservação de 61 espécies de treze bacias hidrográficas no Cone Sul. Na segunda abordagem foi avaliado o padrão geográfico de uma interação interespecífica simbiótica do tipo comensalismo através da adequabilidade climática de Elpidium (Ostracoda) e bromélias tanque da Mata Atlântica, além da disponibilidade de habitat para o Elpidium (presença de bromélias tanque) no futuro. Para ambas as abordagens, a mudança climática influenciou diretamente a diminuição das áreas de distribuição dos ostrácodes no futuro. Os resultados da primeira abordagem mostraram uma diminuição da riqueza de ostrácodes nas bacias do Cone Sul da América do Sul, e diferentes composições de espécies em 2050 e 2080, em ambos os cenários moderado-otimista e pessimista. A diminuição nas áreas de distribuição de ostrácodes alterará o status de conservação de diversas espécies para potencialmente ameaçadas. As áreas de ocorrência de Elpidium serão mais limitadas em tempos futuros e haverá menor disponibilidade de habitat, ou seja, menos espécies de bromélias tanque para interação. Em geral, os regimes de precipitação e temperatura são sincronizados com eventos fenológicos de história de vida das espécies, os quais determinam a direção da dispersão para o conjunto ambiental das condições ideais de sobrevivência no futuro. Os resultados contribuem como subsídio para incluir ostrácodes (e outros invertebrados) em planos de conservação de seus habitats em escalas geográficas mais amplas.
    Description: PhD
    Keywords: Ostracoda (Crustacea) ; Microcrustáceos de água doce ; Invertebrados aquáticos ; Macroecologia ; Mudanças climáticas ; Bacias hidrográficas ; Mudanças climáticas globais ; Nicho ecológico ; Variação temporal ; Aquecimento global ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::C::Crustaceans (freshwater) ; ASFA_2015::I::Impacts ; ASFA_2015::C::Climatic changes ; ASFA_2015::E::Ecological niches ; ASFA_2015::R::River basins ; ASFA_2015::G::Global warming ; ASFA_2015::C::Conservation ; ASFA_2015::T::Temporal variations
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 124pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 52
    facet.materialart.
    Unknown
    Diatomáceas na bioindicação de mudanças paleoambientais em planície de inundação. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-06
    Description: The paleolimnological approach one of the few existing methods that assesses the rate of ecosystem changes in freshwater environments, over large time scales, and one of the few approaches that have been used successfully to infer pre-impact limnological conditions and post-perturbation trajectories of environmental changes. The diatoms are the most effective bioindicator microfossils in paleolimnological research in providing information on environmental changes in aquatic ecosystems. Among the ecosystems that have been altered over time, the floodplain of the Upper Paraná River in recent decades has been subjected to several natural and man-made disturbances, mainly hydroelectric dams, which have affected the entire ecosystem and the known freshwater biodiversity. Therefore, the temporal pattern of abundance and functional traits of the diatoms community of two lakes inserted in this floodplain was investigated, using the paleolimnological approach to infer a history of possible environmental changes. The results of these studies were divided into three works. Through the bioindication of the most abundant diatom species in Garças Lake and Patos Lake, it was possible to observe evidence of physical, chemical and hydrological changes in both environments over the last 100 years. It is inferred that both environments may have been influenced by effects imposed by the upstream reservoirs and climatic events. As well as the greater variation and reduction in functional diversity found in Garças Lake, which is closer to dams, indicates a greater influence of the reservoirs. Despite this, in different periods, both lakes have replaced and simplified similar functional categories, which are related to low water conditions and high turbulence in the water column, which were recurrent after the damming periods
    Description: A abordagem paleolimnológica é um dos poucos métodos existentes que avalia a taxa de alterações ecossistêmicas em ambientes de água doce em grandes escalas temporais e uma das poucas abordagens que têm sido usada com sucesso para inferir condições limnológicas pré-impacto e trajetórias pós-perturbação de mudanças ambientais. Sendo as diatomáceas os microfósseis bioindicadores mais eficazes na pesquisa paleolimnológica no fornecimento de informações sobre alterações ambientais nos ecossistemas aquáticos. Dentre os ecossistemas que tem sido alterado ao longo do tempo, tem-se como exemplo a Planície de inundação do alto rio Paraná, a qual nas últimas décadas tem sido submetida a diversos distúrbios naturais e antrópicos, principalmente por represas hidrelétricas, que afetaram todo o ecossistema e a biodiversidade de água doce conhecida. Portanto, investigou-se o padrão temporal da abundância e de traços funcionais da comunidade de diatomáceas de dois lagos inseridos nesta planície de inundação, utilizando a abordagem paleolimnológica para inferir um histórico de possíveis mudanças ambientais. Através da bioindicação das espécies de diatomáceas mais abundantes do lago das Garças e do lago dos Patos, foi possível observar evidências de mudanças físicas, químicas e hidrológicas em ambos os ambientes nos aproximados últimos 100 anos. Infere-se que ambos os ambientes podem ter tido influência de efeitos impostos pelos reservatórios a montante e eventos climáticos. Como também a maior variação e redução da diversidade funcional encontrado no lago das Garças, o qual está mais próximo de barragens, indica uma maior influência dos represamentos. Apesar disso, em períodos distintos, ambos os lagos apresentaram substituição e simplificação de categorias funcionais similares, as quais estão relacionadas com condições de águas baixas e alta turbulência da coluna d’água, as quais foram recorrentes após os períodos de represamento.
    Description: PhD
    Keywords: Diatomáceas (Bacillariophyta) de água doce ; Algas diatomáceas epilíticas ; Diatomáceas fósseis ; Algas unicelulares de água doce ; Paleolimnologia ; Comunidades, Ecologia de ; Bioindicadores ; Mudanças paleoambientais ; Lagos ; Lagos das Garças e dos Patos ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Algae ; ASFA_2015::D::Diatoms ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::B::Bioindicators ; ASFA_2015::P::Palaeolimnology ; ASFA_2015::F::Fossil diatoms ; ASFA_2015::L::Lakes ; ASFA_2015::F::Floodplains ; ASFA_2015::T::Taxonomy
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 125pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 53
    facet.materialart.
    Unknown
    Projected effects of climate change on Pseudo-nitzschia bloom dynamics in the Gulf of Maine (2022)
    Elsevier
    Details
    Publication Date: 2022-07-20
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Clark, S., Hubbard, K., Ralston, D., McGillicuddy, D., Stock, C., Alexander, M., & Curchitser, E. Projected effects of climate change on Pseudo-nitzschia bloom dynamics in the Gulf of Maine. Journal of Marine Systems, 230, (2022): 103737, https://doi.org/10.1016/j.jmarsys.2022.103737.
    Description: Worldwide, warming ocean temperatures have contributed to extreme harmful algal bloom events and shifts in phytoplankton species composition. In 2016 in the Gulf of Maine (GOM), an unprecedented Pseudo-nitzschia bloom led to the first domoic-acid induced shellfishery closures in the region. Potential links between climate change, warming temperatures, and the GOM Pseudo-nitzschia assemblage, however, remain unexplored. In this study, a global climate change projection previously downscaled to 7-km resolution for the Northwest Atlantic was further refined with a 1–3-km resolution simulation of the GOM to investigate the effects of climate change on HAB dynamics. A 25-year time slice of projected conditions at the end of the 21st century (2073–2097) was compared to a 25-year hindcast of contemporary ocean conditions (1994–2018) and analyzed for changes to GOM inflows, transport, and Pseudo-nitzschia australis growth potential. On average, climate change is predicted to lead to increased temperatures, decreased salinity, and increased stratification in the GOM, with the largest changes occurring in the late summer. Inflows from the Scotian Shelf are projected to increase, and alongshore transport in the Eastern Maine Coastal Current is projected to intensify. Increasing ocean temperatures will likely make P. australis growth conditions less favorable in the southern and western GOM but improve P. australis growth conditions in the eastern GOM, including a later growing season in the fall, and a longer growing season in the spring. Combined, these changes suggest that P. australis blooms in the eastern GOM could intensify in the 21st century, and that the overall Pseudo-nitzschia species assemblage might shift to warmer-adapted species such as P. plurisecta or other Pseudo-nitzschia species that may be introduced.
    Description: This research was funded by the National Science Foundation (Grant Number OCE-1840381), the National Institute of Environmental Health Sciences (Grant Number 1P01ES028938), the Woods Hole Center for Oceans and Human Health, and the Academic Programs Office of the Woods Hole Oceanographic Institution.
    Keywords: Gulf of Maine ; ROMS ; Pseudo-nitzschia ; Climate change ; Harmful algal blooms
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 54
    facet.materialart.
    Unknown
    Efeito temporal na parasitofauna do bagre invasor Trachelyopterus galeatus (Linnaeus, 1766) de uma planície Neotropical. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-12-06
    Description: Aquatic environments have been anthropically influenced over the years, mainly with the construction of dams and hydroelectric plants. However, few studies evaluate how the parasitic fauna can be influenced in the long term by these environmental changes. Possible changes in the composition of endoparasites of the invasive fish Trachelyopterus galeatus in the upper Paraná River floodplain were investigated over a 27-year study period. 79 fish were analyzed in period 1 (1993) and 31 in period 2 (2019/2020). In the first period, the fish showed higher values in the variables weight (g) and standard length (cm), when compared to period 2. A total of five species of endoparasites were found, three per period. Although the richness was the same, the composition of endoparasites differed between the periods, as only one species of digenetic (Microrchis oligovitellum) parasitized the host in both periods of study. It was found that both the development of the fish and its endoparasites were affected over time. It is noteworthy that the beginning of operation of the Porto Primavera dam, located upstream of the plain, occurred between the two sampling periods (1999), and caused several environmental changes, possibly being the main responsible for these changes in the parasitofauna. Most endoparasites require intermediate hosts to complete their life cycles. Therefore, a modified environment may lose diversity and ecological interactions, as it affects the populations they use during the transmission process between hosts. This may explain the difference found in the infracommunities of T. galeatus parasites, emphasizing, through the results obtained, the importance of including these organisms in studies that evaluate environmental impacts caused by anthropic actions
    Description: Ambientes aquáticos têm sido influenciado antropicamente ao longo dos anos, principalmente com a construção de barragens e usinas hidrelétricas. Contudo, poucos estudos avaliam como a fauna parasitária pode ser influenciada a longo prazo por essas mudanças ambientais. Investigou-se possíveis alterações na composição de endoparasitas do peixe invasor Trachelyopterus galeatus na planície de inundação do alto rio Paraná, em um intervalo de 27 anos de estudo. Foram analisados 79 peixes no período 1 (1993) e 31 no período 2 (2019/2020). No primeiro período, os peixes apresentaram maiores valores nas variáveis peso (g) e comprimento padrão (cm), quando comparados com o período 2. Encontrou-se um total de cinco espécies de endoparasitas, sendo três por período. Apesar da riqueza ter sido igual, a composição de endoparasitas diferiu entre os períodos, pois apenas uma espécie de digenético (Microrchis oligovitellum) parasitou o hospedeiro nos dois períodos de estudo. Constatou-se que tanto o desenvolvimento do peixe quanto seus endoparasitas foram afetados ao longo do tempo. Destaca-se que o início do funcionamento da barragem de Porto Primavera, localizada à montante da planície, ocorreu entre os dois períodos de amostragem (1999), e provocou diversas alterações ambientais, sendo, possivelmente, a principal responsável por essas mudanças da parasitofauna. A maioria dos endoparasitas requer hospedeiros intermediários para completar seus ciclos de vida. Portanto, um ambiente modificado, pode perder diversidade e interações ecológicas, visto que afeta as populações que eles utilizam durante o processo de transmissão entre hospedeiros. Isso pode explicar a diferença encontrada nas infracomunidades de parasitas de T. galeatus, enfatizando, por meio dos resultados obtidos, a importância de incluir esses organismos nos estudos que avaliam impactos ambientais causados por ações antrópicas.
    Description: Masters
    Keywords: Fauna endoparasitária (Platyhelminthes). ; Trachelyopterus galeatus (Linnaeus, 1766) “cangati”. ; Peixes siluriformes. ; Parasitismo. ; Ecologia. ; Parasitismo em peixes de água doce. ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::P::Parasitism ; ASFA_2015::P::Parasites
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 25pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 55
    facet.materialart.
    Unknown
    Increasing inhomogeneity of the global ocean (2022)
    American Geophysical Union
    Details
    Publication Date: 2022-12-23
    Description: Author Posting. © American Geophysical Union, 2022. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geophysical Research Letters 49(12), (2022): e2021GL097598, https://doi.org/10.1029/2021GL097598.
    Description: The ocean is inhomogeneous in hydrographic properties with diverse water masses. Yet, how this inhomogeneity has evolved in a rapidly changing climate has not been investigated. Using multiple observational and reanalysis datasets, we show that the spatial standard deviation (SSD) of the global ocean has increased by 1.4 ± 0.1% in temperature and 1.5 ± 0.1% in salinity since 1960. A newly defined thermohaline inhomogeneity index, a holistic measure of both temperature and salinity changes, has increased by 2.4 ± 0.1%. Climate model simulations suggest that the observed ocean inhomogeneity increase is dominated by anthropogenic forcing and projected to accelerate by 200%–300% during 2015–2100. Geographically, the rapid upper-ocean warming at mid-to-low latitudes dominates the temperature inhomogeneity increase, while the increasing salinity inhomogeneity is mainly due to the amplified salinity contrast between the subtropical and subpolar latitudes.
    Description: This work is supported by the Strategic Priority Research Program of Chinese Academy of Sciences (grant XDB42000000 and XDB40000000), the National Key R&D Program of China (2017YFA0603200), and the Shandong Provincial Natural Science Foundation (ZR2020JQ17), and the U.S. National Science Foundation Physical Oceanography Program (OCE- 2048336).
    Description: 2022-12-23
    Keywords: Global ocean ; Temperature ; Salinity ; Spatial inhomogeneity ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 56
    facet.materialart.
    Unknown
    Understanding the combined effects of multiple stressors: a new perspective on a longstanding challenge (2022)
    Elsevier
    Details
    Publication Date: 2022-05-26
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Pirotta, E., Thomas, L., Costa, D., Hall, A., Harris, C., Harwood, J., Kraus, S., Miller, P., Moore, M., Photopoulou, T., Rolland, R., Schwacke, L., Simmons, S., Southall, B., & Tyack, P. Understanding the combined effects of multiple stressors: a new perspective on a longstanding challenge. Science of The Total Environment, 821, (2022): 153322, https://doi.org/10.1016/j.scitotenv.2022.153322.
    Description: Wildlife populations and their habitats are exposed to an expanding diversity and intensity of stressors caused by human activities, within the broader context of natural processes and increasing pressure from climate change. Estimating how these multiple stressors affect individuals, populations, and ecosystems is thus of growing importance. However, their combined effects often cannot be predicted reliably from the individual effects of each stressor, and we lack the mechanistic understanding and analytical tools to predict their joint outcomes. We review the science of multiple stressors and present a conceptual framework that captures and reconciles the variety of existing approaches for assessing combined effects. Specifically, we show that all approaches lie along a spectrum, reflecting increasing assumptions about the mechanisms that regulate the action of single stressors and their combined effects. An emphasis on mechanisms improves analytical precision and predictive power but could introduce bias if the underlying assumptions are incorrect. A purely empirical approach has less risk of bias but requires adequate data on the effects of the full range of anticipated combinations of stressor types and magnitudes. We illustrate how this spectrum can be formalised into specific analytical methods, using an example of North Atlantic right whales feeding on limited prey resources while simultaneously being affected by entanglement in fishing gear. In practice, case-specific management needs and data availability will guide the exploration of the stressor combinations of interest and the selection of a suitable trade-off between precision and bias. We argue that the primary goal for adaptive management should be to identify the most practical and effective ways to remove or reduce specific combinations of stressors, bringing the risk of adverse impacts on populations and ecosystems below acceptable thresholds.
    Description: This work was supported by the Office of Naval Research [grant numbers N000142012697, N000142112096]; and the Strategic Environmental Research and Development Program [grant numbers RC20-1097, RC20-7188, RC21-3091].
    Keywords: Adaptive management ; Climate change ; Combined effects ; Mechanistic modelling ; Multiple stressors ; Population consequences
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 57
    facet.materialart.
    Unknown
    A new structure for the Sea Ice Essential Climate variables of the Global Climate Observing System (2022)
    American Meteorological Society
    Details
    Publication Date: 2022-12-01
    Description: Author Posting. © American Meteorological Society, 2022. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 103(6), (2022): E1502-E1521, https://doi.org/10.1175/bams-d-21-0227.1.
    Description: Climate observations inform about the past and present state of the climate system. They underpin climate science, feed into policies for adaptation and mitigation, and increase awareness of the impacts of climate change. The Global Climate Observing System (GCOS), a body of the World Meteorological Organization (WMO), assesses the maturity of the required observing system and gives guidance for its development. The Essential Climate Variables (ECVs) are central to GCOS, and the global community must monitor them with the highest standards in the form of Climate Data Records (CDR). Today, a single ECV—the sea ice ECV—encapsulates all aspects of the sea ice environment. In the early 1990s it was a single variable (sea ice concentration) but is today an umbrella for four variables (adding thickness, edge/extent, and drift). In this contribution, we argue that GCOS should from now on consider a set of seven ECVs (sea ice concentration, thickness, snow depth, surface temperature, surface albedo, age, and drift). These seven ECVs are critical and cost effective to monitor with existing satellite Earth observation capability. We advise against placing these new variables under the umbrella of the single sea ice ECV. To start a set of distinct ECVs is indeed critical to avoid adding to the suboptimal situation we experience today and to reconcile the sea ice variables with the practice in other ECV domains.
    Description: PH’s contribution was funded under the Australian Government’s Antarctic Science Collaboration Initiative program, and contributes to Project 6 of the Australian Antarctic Program Partnership (ASCI000002). PH acknowledges support through the Australian Antarctic Science Projects 4496 and 4506, and the International Space Science Institute (Bern, Switzerland) project #405.
    Description: 2022-12-01
    Keywords: Sea ice ; Climate change ; Climatology ; Climate records
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 58
    facet.materialart.
    Unknown
    OneArgo: a new paradigm for observing the global ocean (2022)
    Marine Technology Society
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Owens, W., Zilberman, N., Johnson, K., Claustre, H., Scanderbeg, M., Wijffels, S., & Suga, T. OneArgo: a new paradigm for observing the global ocean. Marine Technology Society Journal, 56(3), (2022): 84–90, https://doi.org/10.4031/MTSJ.56.3.8.
    Description: OneArgo is a major expansion of the Argo program, which has provided two decades of transformative physical data for the upper 2 km of the global ocean. The present Argo array will be expanded in three ways: (1) Global Core: the existing upper ocean measurements will be extended to high latitudes and marginal seas and with enhanced coverage in the tropics and western boundaries of the major ocean basins; (2) Deep: deep ocean measurements will be obtained for the 50% of the global oceans that are below 2,000-m depth; and (3) Biogeochemical: dissolved oxygen, pH, nitrate, chlorophyll, optical backscatter, and irradiance data will be collected to investigate biogeochemical variability of the upper ocean and the processes by which these cycles respond to a changing climate. The technology and infrastructure necessary for this expansion is now being developed through large-scale regional pilots to further refine the floats and sensors and to demonstrate the utility of these measurements. Further innovation is expected to improve the performance of the floats and sensors and to develop the analyses necessary to provide research-quality data. A fully global OneArgo should be operational within 5–10 years.
    Description: In the United States, the National Science Foundation–funded Global Ocean Biogeochemistry Array (GO-BGC; https://go-bgc.org).
    Keywords: Argo floats ; Argo sensors ; OneArgo ; Climate change ; Biogeochemical measurements
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 59
    facet.materialart.
    Unknown
    Carbon accumulation, flux, and fate in Stordalen Mire, a permafrost peatland in transition (2022)
    American Geophysical Union
    Details
    Publication Date: 2022-10-26
    Description: Author Posting. © American Geophysical Union, 2022. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 36(1), (2022): e2021GB007113, https://doi.org/10.1029/2021GB007113.
    Description: Stordalen Mire is a peatland in the discontinuous permafrost zone in arctic Sweden that exhibits a habitat gradient from permafrost palsa, to Sphagnum bog underlain by permafrost, to Eriophorum-dominated fully thawed fen. We used three independent approaches to evaluate the annual, multi-decadal, and millennial apparent carbon accumulation rates (aCAR) across this gradient: seven years of direct semi-continuous measurement of CO2 and CH4 exchange, and 21 core profiles for 210Pb and 14C peat dating. Year-round chamber measurements indicated net carbon balance of −13 ± 8, −49 ± 15, and −91 ± 43 g C m−2 y−1 for the years 2012–2018 in palsa, bog, and fen, respectively. Methane emission offset 2%, 7%, and 17% of the CO2 uptake rate across this gradient. Recent aCAR indicates higher C accumulation rates in surface peats in the palsa and bog compared to current CO2 fluxes, but these assessments are more similar in the fen. aCAR increased from low millennial-scale levels (17–29 g C m−2 y−1) to moderate aCAR of the past century (72–81 g C m−2 y−1) to higher recent aCAR of 90–147 g C m−2 y−1. Recent permafrost collapse, greater inundation and vegetation response has made the landscape a stronger CO2 sink, but this CO2 sink is increasingly offset by rising CH4 emissions, dominated by modern carbon as determined by 14C. The higher CH4 emissions result in higher net CO2-equivalent emissions, indicating that radiative forcing of this mire and similar permafrost ecosystems will exert a warming influence on future climate.
    Description: We would like to acknowledge the following funding in support of this project: Swedish Research Council (Vetenskapsrådet, VR) grants (NT 2007-4547 and NT 2013-5562 to P. Crill), U.S. Department of Energy grants (DE-SC0004632 and DE-SC0010580 to V. Rich and S. Saleska), and U.S. National Science Foundation MacroSystems Biology grant (NSF EF #1241037, PI Varner). This work was supported by the U.S. Department of Energy, Office of Science, Office of Biological and Environmental Research under the Genomic Science program. We also acknowledge funding from the National Science Foundation for the EMERGE Biology Integration Institute, NSF Award #2022070.
    Description: 2022-07-03
    Keywords: Peat ; Carbon cycling ; Permafrost ; Carbon-14 ; Lead-210 ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 60
    facet.materialart.
    Unknown
    Summer surface CO2 dynamics on the Bering Sea and eastern Chukchi Sea shelves from 1989 to 2019 (2022)
    American Geophysical Union
    Details
    Publication Date: 2022-10-26
    Description: Author Posting. © American Geophysical Union, 2022. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 127(1), (2022): e2021JC017424, https://doi.org/10.1029/2021JC017424.
    Description: By compiling boreal summer (June to October) CO2 measurements from 1989 to 2019 on the Bering and eastern Chukchi Sea shelves, we find that the study areas act as a CO2 sink except when impacted by river runoff and wind-driven upwelling. The CO2 system in this area is seasonally dominated by the biological pump especially in the northern Bering Sea and near Hanna Shoal, while wind-driven upwelling of CO2-rich bottom water can cause episodic outgassing. Seasonal surface ΔfCO2 (oceanic fCO2 – air fCO2) is dominantly driven by temperature only during periods of weak CO2 outgassing in shallow nearshore areas. However, after comparing the mean summer ΔfCO2 during the periods of 1989–2013 and 2014–2019, we suggest that temperature does drive long-term, multi-decadal patterns in ΔfCO2. In the northern Chukchi Sea, rapid warming concurrent with reduced seasonal sea-ice persistence caused the regional summer CO2 sink to decrease. By contrast, increasing primary productivity caused the regional summer CO2 sink on the Bering Sea shelf to increase over time. While additional time series are needed to confirm the seasonal and annual trajectory of CO2 changes and ocean acidification in these dynamic and spatially complex ecosystems, this study provides a meaningful mechanistic analysis of recent changes in inorganic carbonate chemistry. As high-resolution time series of inorganic carbonate parameters lengthen and short-term variations are better constrained in the coming decades, we will have stronger confidence in assessing the mechanisms contributing to long-term changes in the source/sink status of regional sub-Arctic seas.
    Description: We gratefully acknowledge the support of the funding agencies that supported this analysis, including the New Sustained Observations for Arctic Research project and the DBO-NCIS project (NA14OAR4320158, NA19OAR4320074) from the NOAA Arctic Research Program.
    Description: 2022-06-17
    Keywords: Pacific Arctic region ; Sea-air CO2 flux ; Ocean acidification ; Climate change ; Sea-ice loss ; Surface ocean CO2 Atlas
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 61
    facet.materialart.
    Unknown
    Macrófitas aquáticas na Região Neotropical: riqueza e qualificação das espécies. (2022)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-12-17
    Description: Aquatic macrophytes are macroscopic photosynthetic organisms that encompass several taxonomic groups of plants, with broad limnological characteristics that colonize from marshes to submerged areas, playing a fundamental role in structuring wetlands and affecting aquatic biodiversity. The Neotropical Region, covering from the south of Mexico to the south of Argentina, is characterized for being one of the most biodiverse regions in the world, with a unique biota, many endemic species and a great diversity of environments. As one of the wetlands with the greatest potential in this ecozone and the world, the Paraná-Paraguay basins stand out. The objectives of this thesis were to quantify and qualify the species of aquatic macrophytes that occur in the Neotropical Region and in the Paraná-Paraguay basins, carry out an analysis of hotspots for the Paraná-Paraguay basins and provide current information and indicators of areas of high richness of aquatic macrophytes. A conservation efficiency analysis is also available that correlates areas considered hotspots and the protected areas present in these basins. Data from systematic searches in important bibliographic bases were used to compose the lists and geographic coordinates. A total of 1616 spp. for the Neotropics and 979 species for the Paraná-Paraguay basins. The families with the highest number of species were Cyperaceae Juss. and Poaceae Barnhart in both regions studied. Species richness for the Paraná-Paraguay basins was recorded using occurrence points, with 5 locations with values from 71 to 139 species and 50 locations from 1 to 11 species, with the Lower Paraná River having the lowest number of occurrences and the Lower Paraguay River the largest amount. Sixteen sub-basins considered as hotspots were registered, and these areas coincided with the areas of greatest richness. Approximately 6% of the total ecological hotspot areas are being conserved within protected areas. In conclusion, the results obtained in both surveys reaffirm the high number of species present in these wetlands, highlighting the need for further systematic and taxonomic studies of aquatic macrophytes, seeking to precisely detail these megadiverse regions.
    Description: Macrófitas aquáticas são organismos fotossintetizantes macroscópicos que englobam vários grupos taxonômicos de plantas, com amplas características limnológicas que colonizam desde brejos até áreas submersas,desempenhando papel fundamental na estruturação das áreas úmidas e afetando a biodiversidade aquática. A Região Neotropical, abrange desde o sul do México até o sul da Argentina, caracteriza-se por ser uma das regiões mais biodiversas do mundo, com biota singular, grande número de espécies endêmicas e grande diversidade de ambientes. Como uma das áreas úmidas de maior potencial desta ecozona e do globo, destacam-se as bacias Paraná-Paraguai. Os objetivos dessa tese foram quantificar e qualificar as espécies de macrófitas aquáticas ocorrentes na Região Neotropical e nas bacias Paraná-Paraguai,efetuar análise de hotspots para as bacias Paraná-Paraguai e disponibilizar informações atuais e indicadoras de áreas de alta riqueza de macrófitas aquáticas. Também é disponibilizado uma análise de eficiência de conservação que correlaciona áreas consideradas hotspots e as áreas protegidas presentes nessas bacias. Dados de buscas sistemáticas em importantes bases bibliográficas foram utilizados para compor as listas e coordenadas geográficas. Registrou-se um total de 1616 spp. para os Neotrópicos e 979 espécies para as bacias Paraná-Paraguai. As famílias com maior número de espécies foram Cyperaceae Juss. e Poaceae Barnhart em ambas as regiões estudadas. A riqueza de espécies para as bacias Paraná-Paraguai foi registrada por meio de pontos de ocorrência, apresentando 5 locais com valores de 71 a 139 espécies e 50 locais de 1 a 11 espécies, sendo o Baixo Rio Paraná com a menor quantidade de ocorrências e o Baixo Rio Paraguai a maior quantia. Foram registradas 16 sub-bacias consideradas hotspots, e estas áreas coincidiram com as áreas de maior riqueza. Aproximadamente 6% do total das áreas de hotspots ecológicos estão sendo conservados dentro de áreas protegidas. Em conclusão, os resultados obtidos em ambas as pesquisas reafirmam o alto número de espécies presentes nessas áreas úmidas, deixando evidente a necessidade de mais estudos sistemáticos e taxonômicos para macrófitas aquáticas, em busca de detalhar precisamente essas regiões megadiversas.
    Description: PhD
    Keywords: Macrófitas aquáticas ; Diversidade ; Riqueza de espécies ; Revisão sistemática ; Áreas úmidas ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Macrophytes ; ASFA_2015::W::Wetlands ; ASFA_2015::F::Floodplains ; ASFA_2015::L::Literature reviews ; ASFA_2015::A::Aquatic plants ; ASFA_2015::B::Biodiversity ; ASFA_2015::H::Hot spots
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 448pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 62
    facet.materialart.
    Unknown
    Model responses to CO(2) and warming are underestimated without explicit representation of Arctic small-mammal grazing (2021)
    Ecological Society of America
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Rastetter, E. B., Griffin, K. L., Rowe, R. J., Gough, L., McLaren, J. R., & Boelman, N. T. Model responses to CO(2) and warming are underestimated without explicit representation of Arctic small-mammal grazing. Ecological Applications, (2021): e02478, https://doi.org/10.1002/eap.2478.
    Description: We use a simple model of coupled carbon and nitrogen cycles in terrestrial ecosystems to examine how “explicitly representing grazers” vs. “having grazer effects implicitly aggregated in with other biogeochemical processes in the model” alters predicted responses to elevated carbon dioxide and warming. The aggregated approach can affect model predictions because grazer-mediated processes can respond differently to changes in climate compared with the processes with which they are typically aggregated. We use small-mammal grazers in a tundra as an example and find that the typical three-to-four-year cycling frequency is too fast for the effects of cycle peaks and troughs to be fully manifested in the ecosystem biogeochemistry. We conclude that implicitly aggregating the effects of small-mammal grazers with other processes results in an underestimation of ecosystem response to climate change, relative to estimations in which the grazer effects are explicitly represented. The magnitude of this underestimation increases with grazer density. We therefore recommend that grazing effects be incorporated explicitly when applying models of ecosystem response to global change.
    Description: This work was supported in part by the National Science Foundation under NSF grants 1651722, 1637459, 1603560, 1556772, 1841608 to E.B.R.; 1603777 to N.T.B. and K.L.G.; 1603654 to R.J.R.; 1603760 to L.G.; and 1603677 to J.R.M.
    Keywords: Arctic tundra ; Biogeochemistry ; Carbon cycling ; Carbon-nitrogen ecosystem model ; Climate change ; Nitrogen cycling ; Population cycles ; Small-mammal herbivores
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 63
    facet.materialart.
    Unknown
    Estimating the impact of seep methane oxidation on ocean pH and dissolved inorganic radiocarbon along the US Mid-Atlantic Bight (2021)
    American Geophysical Union
    Details
    Publication Date: 2022-10-27
    Description: Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Biogeosciences 126(1), (2021): e2019JG005621, https://doi.org/10.1029/2019JG005621.
    Description: Ongoing ocean warming can release methane (CH4) currently stored in ocean sediments as free gas and gas hydrates. Once dissolved in ocean waters, this CH4 can be oxidized to carbon dioxide (CO2). While it has been hypothesized that the CO2 produced from aerobic CH4 oxidation could enhance ocean acidification, a previous study conducted in Hudson Canyon shows that CH4 oxidation has a small short‐term influence on ocean pH and dissolved inorganic radiocarbon. Here we expand upon that investigation to assess the impact of widespread CH4 seepage on CO2 chemistry and possible accumulation of this carbon injection along 234 km of the U.S. Mid‐Atlantic Bight. Consistent with the estimates from Hudson Canyon, we demonstrate that a small fraction of ancient CH4‐derived carbon is being assimilated into the dissolved inorganic radiocarbon (mean fraction of 0.5 ± 0.4%). The areas with the highest fractions of ancient carbon coincide with elevated CH4 concentration and active gas seepage. This suggests that aerobic CH4 oxidation has a greater influence on the dissolved inorganic pool in areas where CH4 concentrations are locally elevated, instead of displaying a cumulative effect downcurrent from widespread groupings of CH4 seeps. A first‐order approximation of the input rate of ancient‐derived dissolved inorganic carbon (DIC) into the waters overlying the northern U.S. Mid‐Atlantic Bight further suggests that oxidation of ancient CH4‐derived carbon is not negligible on the global scale and could contribute to deepwater acidification over longer time scales.
    Description: This study was sponsored by U.S. Department of Energy (DE‐FE0028980, awarded to J. D. K; DE‐FE0026195 interagency agreement with C. D. R.). We thank the crew of the R/V Hugh R. Sharp for their support, G. Hatcher, J. Borden, and M. Martini of the USGS for assistance with the LADCP, and Zach Bunnell, Lillian Henderson, and Allison Laubach for additional support at sea.
    Description: 2021-06-23
    Keywords: Radiocarbon ; Methane ; DIC ; Ocean acidification ; Climate change ; U.S Mid-Atlantic Bight
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 64
    facet.materialart.
    Unknown
    Time lags: insights from the U.S. Long Term Ecological Research Network (2021)
    Ecological Society of America
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Rastetter, E. B., Ohman, M. D., Elliott, K. J., Rehage, J. S., Rivera-Monroy, V. H., Boucek, R. E., Castaneda-Moya, E., Danielson, T. M., Gough, L., Groffman, P. M., Jackson, C. R., Miniat, C. F., & Shaver, G. R. Time lags: insights from the U.S. Long Term Ecological Research Network. Ecosphere, 12(5), (2021): e03431, https://doi.org/10.1002/ecs2.3431.
    Description: Ecosystems across the United States are changing in complex ways that are difficult to predict. Coordinated long-term research and analysis are required to assess how these changes will affect a diverse array of ecosystem services. This paper is part of a series that is a product of a synthesis effort of the U.S. National Science Foundation’s Long Term Ecological Research (LTER) network. This effort revealed that each LTER site had at least one compelling scientific case study about “what their site would look like” in 50 or 100 yr. As the site results were prepared, themes emerged, and the case studies were grouped into separate papers along five themes: state change, connectivity, resilience, time lags, and cascading effects and compiled into this special issue. This paper addresses the time lags theme with five examples from diverse biomes including tundra (Arctic), coastal upwelling (California Current Ecosystem), montane forests (Coweeta), and Everglades freshwater and coastal wetlands (Florida Coastal Everglades) LTER sites. Its objective is to demonstrate the importance of different types of time lags, in different kinds of ecosystems, as drivers of ecosystem structure and function and how these can effectively be addressed with long-term studies. The concept that slow, interactive, compounded changes can have dramatic effects on ecosystem structure, function, services, and future scenarios is apparent in many systems, but they are difficult to quantify and predict. The case studies presented here illustrate the expanding scope of thinking about time lags within the LTER network and beyond. Specifically, they examine what variables are best indicators of lagged changes in arctic tundra, how progressive ocean warming can have profound effects on zooplankton and phytoplankton in waters off the California coast, how a series of species changes over many decades can affect Eastern deciduous forests, and how infrequent, extreme cold spells and storms can have enduring effects on fish populations and wetland vegetation along the Southeast coast and the Gulf of Mexico. The case studies highlight the need for a diverse set of LTER (and other research networks) sites to sort out the multiple components of time lag effects in ecosystems.
    Description: This research was supported by the National Science Foundation Long Term Ecological Research program grants to the Arctic (Grants DEB-1637459 and 1026843), California Current (Grants OCE-1637632 and 1026607), Coweeta (Grants DEB-1637522, 1440485, 0823293, 9632854, and 0218001), and Florida Coastal Everglades (Grants DEB-9910514 and 1237517 and DBI-0620409) sites. We also acknowledge the sustained efforts of the CalCOFI program, present and previous staff of the SIO Pelagic Invertebrate Collection, and the late Ed Brinton for his pioneering insights in euphausiid ecology. The Coweeta research and synthesis were also supported by the USDA Forest Service, Southern Research Station, Coweeta Hydrologic Laboratory. Partial funding to VHRM was provided by the U.S. Department of the Interior South-Central Climate Science Center through Cooperative Agreement # G12AC00002.
    Keywords: Climate change ; Climate change detection ; Climate signal filtering ; Ecosystem response ; Special Feature: Forecasting Earth's Ecosystems with Long-Term Ecological Research
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 65
    facet.materialart.
    Unknown
    Deep North Atlantic last glacial maximum salinity reconstruction (2021)
    American Geophysical Union
    Details
    Publication Date: 2022-10-19
    Description: Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography and Paleoclimatology 36(7), (2021): e2020PA004088, https://doi.org/10.1029/2020PA004088.
    Description: We reconstruct deep water-mass salinities and spatial distributions in the western North Atlantic during the Last Glacial Maximum (LGM, 19–26 ka), a period when atmospheric CO2 was significantly lower than it is today. A reversal in the LGM Atlantic meridional bottom water salinity gradient has been hypothesized for several LGM water-mass reconstructions. Such a reversal has the potential to influence climate, ocean circulation, and atmospheric CO2 by increasing the thermal energy and carbon storage capacity of the deep ocean. To test this hypothesis, we reconstructed LGM bottom water salinity based on sedimentary porewater chloride profiles in a north-south transect of piston cores collected from the deep western North Atlantic. LGM bottom water salinity in the deep western North Atlantic determined by the density-based method is 3.41–3.99 ± 0.15% higher than modern values at these sites. This increase is consistent with: (a) the 3.6% global average salinity change expected from eustatic sea level rise, (b) a northward expansion of southern sourced deep water, (c) shoaling of northern sourced deep water, and (d) a reversal of the Atlantic's north-south deep water salinity gradient during the LGM.
    Description: This work was supported by the US National Science Foundation (grant numbers 1433150 and 1537485).
    Description: 2021-10-24
    Keywords: Carbon cycle ; Climate change ; Deep water ; Glaciation ; Meridional overturning circulation ; Paleosalinity ; Porewater
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 66
    facet.materialart.
    Unknown
    Marine sedimentary records of chemical weathering evolution in the western Himalaya since 17 Ma (2021)
    Geological Society of America
    Details
    Publication Date: 2022-10-19
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Zhou, P., Ireland, T., Murray, R. W., & Clift, P. D. Marine sedimentary records of chemical weathering evolution in the western Himalaya since 17 Ma. Geosphere, 17(3), (2021): 824–853, https://doi.org/10.1130/GES02211.1.
    Description: The Indus Fan derives sediment from the western Himalaya and Karakoram. Sediment from International Ocean Discovery Program drill sites in the eastern part of the fan coupled with data from an industrial well near the river mouth allow the weathering history of the region since ca. 16 Ma to be reconstructed. Clay minerals, bulk sediment geochemistry, and magnetic susceptibility were used to constrain degrees of chemical alteration. Diffuse reflectance spectroscopy was used to measure the abundance of moisture-sensitive minerals hematite and goethite. Indus Fan sediment is more weathered than Bengal Fan material, probably reflecting slow transport, despite the drier climate, which slows chemical weathering rates. Some chemical weathering proxies, such as K/Si or kaolinite/(illite + chlorite), show no temporal evolution, but illite crystallinity and the chemical index of alteration do have statistically measurable decreases over long time periods. Using these proxies, we suggest that sediment alteration was moderate and then increased from 13 to 11 Ma, remained high until 9 Ma, and then reduced from that time until 6 Ma in the context of reduced physical erosion during a time of increasing aridity as tracked by hematite/goethite values. The poorly defined reducing trend in weathering intensity is not clearly linked to global cooling and at least partly reflects regional climate change. Since 6 Ma, weathering has been weak but variable since a final reduction in alteration state after 3.5 Ma that correlates with the onset of Northern Hemispheric glaciation. Reduced or stable chemical weathering at a time of falling sedimentation rates is not consistent with models for Cenozoic global climate change that invoke greater Himalayan weathering fluxes drawing down atmospheric CO2 but are in accord with the idea of greater surface reactivity to weathering.
    Description: This study was made possible by samples provided by the IODP. The work was partially funded by a grant from The U.S. Science Support Program (USSSP), as well as additional funding from the Charles T. McCord Jr. Endowed Chair in petroleum geology at LSU.
    Keywords: Alteration ; Arabian Sea ; Arid environment ; Asia ; Bengal Fan ; Chemical composition ; Chemical weathering ; Chlorite ; Chlorite group ; Clay minerals ; Climate change ; Cooling ; Crystallinity ; Emission spectra ; Erosion ; Expedition 355 ; Glaciation ; Goethite ; Grain size ; Hematite ; Himalayas ; ICP mass spectra ; Illite ; Indian Ocean ; Indus Fan ; International Ocean Discovery Program ; IODP Site U1456 ; IODP Site U1457 ; Kaolinite ; Karakoram ; Magnetic properties ; Magnetic susceptibility ; Marine environment ; Mass spectra ; Mineral assemblages ; Moisture ; Oxides ; Paleoclimatology ; Paleoenvironment ; Paleomagnetism ; Provenance ; Reactivity ; Reconstruction ; Sediment transport ; Sedimentary rocks ; Sedimentation ; Sedimentation rates ; Sheet silicates ; Silicates ; Spectra ; Terrestrial environment ; Transport ; Weathering
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 67
    facet.materialart.
    Unknown
    Heterogeneous Changes to Wetlands in the Canadian Prairies Under Future Climate (2021)
    American Geophysical Union
    Details
    Publication Date: 2022-10-20
    Description: Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Water Resources Research 57(7), (2021): e2020WR028727, https://doi.org/10.1029/2020WR028727.
    Description: Numerous wetlands in the prairies of Canada provide important ecosystem services, yet are threatened by climate and land-use changes. Understanding the impacts of climate change on prairie wetlands is critical to effective conservation planning. In this study, we construct a wetland model with surface water balance and ecoregions to project future distribution of wetlands. The climatic conditions downscaled from the Weather Research and Forecasting model were used to drive the Noah-MP land surface model to obtain surface water balance. The climate change perturbation is derived from an ensemble of general circulation models using the pseudo global warming method, under the RCP8.5 emission scenario by the end of 21st century. The results show that climate change impacts on wetland extent are spatiotemporally heterogenous. Future wetter climate in the western Prairies will favor increased wetland abundance in both spring and summer. In the eastern Prairies, particularly in the mixed grassland and mid-boreal upland, wetland areas will increase in spring but experience enhanced declines in summer due to strong evapotranspiration. When these effects of climate change are considered in light of historical drainage, they suggest a need for diverse conservation and restoration strategies. For the mixed grassland in the western Canadian Prairies, wetland restoration will be favorable, while the highly drained eastern Prairies will be challenged by the intensified hydrological cycle. The outcomes of this study will be useful to conservation agencies to ensure that current investments will continue to provide good conservation returns in the future.
    Description: Z. Zhang was funded by a Mitacs Accelerate Fellowship funded by Ducks Unlimited Canada's Institute for Wetland and Waterfowl Research. Z. Zhang, Z. Li, and Y. Li acknowledge the financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant, and Global Water Futures Program, Canada First Research Excellence Fund. This project was supported by grants from Wildlife Habitat Canada, Bass Pro Shops Cabela’s Outdoor Fund, and the Alberta NAWMP Partnership.
    Description: 2021-12-21
    Keywords: Wetland ; Hydrology ; Climate change ; Prairie Pothole Region ; Waterfowl ; Conservation
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 68
    facet.materialart.
    Unknown
    A predação por peixes em sinergia com o estado trófico determina a estrutura de tamanho da comunidade zooplanctônica em lagoas rasas de uma planície de inundação neotropical, Brasil. (2021)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-27
    Description: The zooplankton body size is influenced by several factors, which in the natural ecosystem, can act directly, or interact, indirectly affecting the community structure. Water temperature, food availability, trophic status and predation by vertebrates are the main factors that influence the size structure of this community. Here we investigate how these factors can act on this characteristic of zooplankton directly or indirectly, mediated by the interaction between the factors. For this, we use a structural equation model that allows investigating complex interactions in natural ecosystems. The trophic state and the predation by fish were the main size planters of zooplankton. The trophic state positively influenced the small zooplankton, and indirectly the large zooplankton, mediated by the increase in fish abundance. The results indicated that the community size structure was regulated by top-down (predation) and bottom-up (nutrient availability) mechanisms, however the magnitude of the relationships was variable. Therefore, the results of the present study show that in tropical aquatic ecosystems there is a complex web of interactions that determine the structure of the zooplankton community.
    Description: O tamanho corporal do zooplâncton é influenciado por diversos fatores, que no ecossistema natural, podem agir de forma direta, ou interagir, afetando indiretamente a estrutura da comunidade. Temperatura da água, disponibilidade de alimento, estado trófico e predação por vertebrados são os principais fatores que influenciam na estrutura de tamanho desta comunidade. Aqui investigamos como estes fatores podem agir sobre a essa característica do zooplâncton de forma direta ou indireta, mediada pela interação entre os fatores. Para isso, utilizamos um modelo de equação estrutural que permite investigar complexas interações em ecossistemas naturais. O estado trófico e a predação por peixes foram os principais estruturadores de tamanho do zooplâncton. O estado trófico influenciou positivamente o zooplâncton de pequeno porte, e indiretamente o zooplâncton de grande porte, mediado pelo aumento na abundância dos peixes. Os resultados indicaram que a estrutura de tamanho da comunidade foi regulada por mecanismos top-down (predação) e bottom-up (disponibilidade de nutrientes), entretanto a magnitude das relações foi variável. Portanto, os resultados do estudo evidenciam que em ecossistemas aquáticos tropicais existe uma complexa teia de interações que determinam a estrutura da comunidade zooplanctônica.
    Description: Masters
    Keywords: Zooplâncton de água doce ; Ecologia de ecossistemas ; Estado trófico ; Tamanho corporal ; Predação ; ASFA_2015::Y::Zooplankton ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::E::Ecosystems ; ASFA_2015::P::Predation ; ASFA_2015::F::Food webs ; ASFA_2015::B::Body size ; ASFA_2015::F::Floodplains ; ASFA_2015::T::Trophic status
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 40pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 69
    facet.materialart.
    Unknown
    Cancelation of deglacial thermosteric sea level rise by a barosteric effect (2021)
    American Meteorological Society
    Details
    Publication Date: 2022-05-26
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 50(12),(2020): 3623-3639, https://doi.org/10.1175/JPO-D-20-0173.1
    Description: Sea level rise over the last deglaciation is dominated by the mass of freshwater added to the oceans by the melting of the great ice sheets. While the steric effect of changing seawater density is secondary over the last 20 000 years, processes connected to deglacial warming, the redistribution of salt, and the pressure load of meltwater all influence sea level rise by more than a meter. Here we develop a diagnostic for steric effects that is valid when oceanic mass is changing. This diagnostic accounts for seawater compression due to the added overlying pressure of glacial meltwater, which is here defined to be a barosteric effect. Analysis of three-dimensional global seawater reconstructions of the last deglaciation indicates that thermosteric height change (1.0–1.5 m) is counteracted by barosteric (−1.9 m) and halosteric (from −0.4 to 0.0 m) effects. The total deglacial steric effect from −0.7 to −1.1 m has the opposite sign of analyses that assume that thermosteric expansion is dominant. Despite the vertical oceanic structure not being well constrained during the Last Glacial Maximum, net seawater contraction appears robust as it occurs in four reconstructions that were produced using different paleoceanographic datasets. Calculations that do not account for changes in ocean pressure give the misleading impression that steric effects enhanced deglacial sea level rise.
    Description: GG is supported by NSF OCE-1536380 and OCE-1760878.
    Description: 2021-06-01
    Keywords: Abyssal circulation ; Sea level ; Water masses/storage ; Climate change ; Glaciation ; Water budget/balance
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 70
    facet.materialart.
    Unknown
    Paleoclimate constraints on the spatiotemporal character of past and future droughts (2021)
    American Meteorological Society
    Details
    Publication Date: 2022-05-26
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 33(22), (2020): 9883-9903, https://doi.org/10.1175/JCLI-D-20-0004.1.
    Description: Machine-learning-based methods that identify drought in three-dimensional space–time are applied to climate model simulations and tree-ring-based reconstructions of hydroclimate over the Northern Hemisphere extratropics for the past 1000 years, as well as twenty-first-century projections. Analyzing reconstructed and simulated drought in this context provides a paleoclimate constraint on the spatiotemporal characteristics of simulated droughts. Climate models project that there will be large increases in the persistence and severity of droughts over the coming century, but with little change in their spatial extent. Nevertheless, climate models exhibit biases in the spatiotemporal characteristics of persistent and severe droughts over parts of the Northern Hemisphere. We use the paleoclimate record and results from a linear inverse modeling-based framework to conclude that climate models underestimate the range of potential future hydroclimate states. Complicating this picture, however, are divergent changes in the characteristics of persistent and severe droughts when quantified using different hydroclimate metrics. Collectively our results imply that these divergent responses and the aforementioned biases must be better understood if we are to increase confidence in future hydroclimate projections. Importantly, the novel framework presented herein can be applied to other climate features to robustly describe their spatiotemporal characteristics and provide constraints on future changes to those characteristics.
    Description: This material is based upon work supported by the National Center for Atmospheric Research, which is a major facility sponsored by the National Science Foundation under Cooperative Agreement 1852977. JAF was also supported by the Regional and Global Model Analysis (RGMA) component of the Earth and Environmental System Modeling Program of the U.S. Department of Energy's Office of Biological & Environmental Research (BER) via National Science Foundation IA 1844590. JS was supported in part by the U.S. National Science Foundation through Grants AGS-1602920 and AGS-1805490, and by the National Oceanic and Atmospheric Administration by Grant NA20OAR4310425. We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in Table 1) for producing and making available their model output. For CMIP, the U.S. Department of Energy’s Program for Climate Model Diagnosis and Intercomparison provides coordinating support and led development of software infrastructure in partnership with the Global Organization for Earth System Science Portal. We thank the editor and two reviewers for comments that greatly improved the quality of this manuscript. This is SOEST Publication No. 11116 and LDEO Publication No. 8450.
    Description: 2021-04-15
    Keywords: Drought ; Climate change ; Paleoclimate ; Climate models ; Climate variability ; Other artificial intelligence/machine learning
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 71
    facet.materialart.
    Unknown
    Deltas in arid environments (2021)
    MDPI
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Day, J., Goodman, R., Chen, Z., Hunter, R., Giosan, L., & Wang, Y. Deltas in arid environments. Water, 13(12), (2021): 1677, https://doi.org/10.3390/w13121677.
    Description: Due to increasing water use, diversion and salinization, along with subsidence and sea-level rise, deltas in arid regions are shrinking worldwide. Some of the most ecologically important arid deltas include the Colorado, Indus, Nile, and Tigris-Euphrates. The primary stressors vary globally, but these deltas are threatened by increased salinization, water storage and diversion, eutrophication, and wetland loss. In order to make these deltas sustainable over time, some water flow, including seasonal flooding, needs to be re-established. Positive impacts have been seen in the Colorado River delta after flows to the delta were increased. In addition to increasing freshwater flow, collaboration among stakeholders and active management are necessary. For the Nile River, cooperation among different nations in the Nile drainage basin is important. River flow into the Tigris-Euphrates River delta has been affected by politics and civil strife in the Middle East, but some flow has been re-allocated to the delta. Studies commissioned for the Indus River delta recommended re-establishment of some monthly water flow to maintain the river channel and to fight saltwater intrusion. However, accelerating climate impacts, socio-political conflicts, and growing populations suggest a dire future for arid deltas.
    Description: This research received no external funding.
    Keywords: Salinization ; Climate change ; Colorado river ; Tigris-Euphrates river ; Nile river ; Indus river
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 72
    facet.materialart.
    Unknown
    Impacts of multiple stressors on a benthic foraminiferal community: a long-term experiment assessing response to ocean acidification, hypoxia and warming (2021)
    Frontiers Media
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2021. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Bernhard, J. M., Wit, J. C., Starczak, V. R., Beaudoin, D. J., Phalen, W. G., & McCorkle, D. C. Impacts of multiple stressors on a benthic foraminiferal community: a long-term experiment assessing response to ocean acidification, hypoxia and warming. Frontiers in Marine Science, 8, (2021): 643339, https://doi.org/10.3389/fmars.2021.643339.
    Description: Ocean chemistry is changing as a result of human activities. Atmospheric carbon dioxide (CO2) concentrations are increasing, causing an increase in oceanic pCO2 that drives a decrease in oceanic pH, a process called ocean acidification (OA). Higher CO2 concentrations are also linked to rising global temperatures that can result in more stratified surface waters, reducing the exchange between surface and deep waters; this stronger stratification, along with nutrient pollution, contributes to an expansion of oxygen-depleted zones (so called hypoxia or deoxygenation). Determining the response of marine organisms to environmental changes is important for assessments of future ecosystem functioning. While many studies have assessed the impact of individual or paired stressors, fewer studies have assessed the combined impact of pCO2, O2, and temperature. A long-term experiment (∼10 months) with different treatments of these three stressors was conducted to determine their sole or combined impact on the abundance and survival of a benthic foraminiferal community collected from a continental-shelf site. Foraminifera are well suited to such study because of their small size, relatively rapid growth, varied mineralogies and physiologies. Inoculation materials were collected from a ∼77-m deep site south of Woods Hole, MA. Very fine sediments (〈53 μm) were used as inoculum, to allow the entire community to respond. Thirty-eight morphologically identified taxa grew during the experiment. Multivariate statistical analysis indicates that hypoxia was the major driving factor distinguishing the yields, while warming was secondary. Species responses were not consistent, with different species being most abundant in different treatments. Some taxa grew in all of the triple-stressor samples. Results from the experiment suggest that foraminiferal species’ responses will vary considerably, with some being negatively impacted by predicted environmental changes, while other taxa will tolerate, and perhaps even benefit, from deoxygenation, warming and OA.
    Description: This work was supported by the US NSF SEES-OA grant OCE-1219948 to JB and the Investment in Science Program at WHOI. DM also received support from the NSF Independent Research and Development Program.
    Keywords: Deoxygenation ; Ocean acidification ; Benthic communities ; Benthic foraminifera ; Climate change ; Propagule bank ; Global warming
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 73
    facet.materialart.
    Unknown
    Importance of Orography for Greenland cloud and melt response to atmospheric blocking (2020)
    American Meteorological Society
    Details
    Publication Date: 2022-05-25
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Hahn, L. C., Storelvmo, T., Hofer, S., Parfitt, R., & Ummenhofer, C. C. Importance of Orography for Greenland cloud and melt response to atmospheric blocking. Journal of Climate, 33(10), (2020): 4187-4206, doi:10.1175/JCLI-D-19-0527.1.
    Description: More frequent high pressure conditions associated with atmospheric blocking episodes over Greenland in recent decades have been suggested to enhance melt through large-scale subsidence and cloud dissipation, which allows more solar radiation to reach the ice sheet surface. Here we investigate mechanisms linking high pressure circulation anomalies to Greenland cloud changes and resulting cloud radiative effects, with a focus on the previously neglected role of topography. Using reanalysis and satellite data in addition to a regional climate model, we show that anticyclonic circulation anomalies over Greenland during recent extreme blocking summers produce cloud changes dependent on orographic lift and descent. The resulting increased cloud cover over northern Greenland promotes surface longwave warming, while reduced cloud cover in southern and marginal Greenland favors surface shortwave warming. Comparison with an idealized model simulation with flattened topography reveals that orographic effects were necessary to produce area-averaged decreasing cloud cover since the mid-1990s and the extreme melt observed in the summer of 2012. This demonstrates a key role for Greenland topography in mediating the cloud and melt response to large-scale circulation variability. These results suggest that future melt will depend on the pattern of circulation anomalies as well as the shape of the Greenland Ice Sheet.
    Description: This research was supported by the Woods Hole Oceanographic Institution Summer Student Fellow program, by the U.S. National Science Foundation under AGS-1355339 to C.C.U., and by the European Research Council through Grant 758005.
    Keywords: Ice sheets ; Blocking ; Cloud cover ; Topographic effects ; Climate change ; Climate variability
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 74
    facet.materialart.
    Unknown
    Fatores determinantes das diversidades beta taxonômica e funcional do zooplâncton em planícies de inundação neotropicais. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-07
    Description: Freshwater ecosystems are changing their natural conditions, influenced and accelerated by human activities. These processes are capable of changing the hydrological regime and the composition of the communities, letting the future of aquatic biodiversity unknown. The construction of dams has been one of the main factors responsible for environmental changes, such as nutrients depletion, increased water transparency and loss of biodiversity in freshwater ecosystems. The aim of our study was to analyze the functional and taxonomic dissimilarity of the zooplankton community and its drivers in response to the effect of the hydrological cycle (drought and rainy), in two highly distinct floodplains, the Upper Paraná River (river with a cascade of dams) and the Amazon. A total of 72 samples were collected (16 AMA dry and 16 on rainy and 20 PAR dry and 20 on rainy) from zooplankton communities as the response variable, phytoplankton as a predictor of food, fish as a predictor of potential predators and limnological variables. Were calculated β-Total diversity and partitioned in the components β-Repl and β-Rich (taxonomic and functional approach). We expect that environmental heterogeneity is going to drive higher values of beta diversity. In sequence, distance-based redundancy analysis (db-RDA) was calculated using the distance matrices generated in the functional and taxonomic beta to assess which are the determinants of zooplankton beta diversity. Thus, we hypothesized that biotic interactions will have stronger relationships with zooplankton dissimilarity during the drought and, limnological variables and spatial component will be more important during rainy season. Greater environmental heterogeneity was found in the Amazon floodplain and also in the dry season. The beta functional and taxonomic diversity of zooplankton showed a similar relationship between the floodplains and between the hydrological periods, represented by the β-Repl component, except for the drought season in the Upper Paraná River, where the functional diversity showed the lowest values, undetected by the taxonomic approach. The factors that influenced the zooplankton beta functional and taxonomic diversity in the two floodplains were different depending on the hydrological period, reflecting once again the difference in environmental heterogeneity and the strength of hydrodynamics within each plain. The analysis of the species and functional traits distribution and, which are the variables structuring this distribution is extremely important to analyze ecosystem processes and services, especially in impacted environments such as the Upper Paraná River floodplain, and a floodplain so biodiverse as the Amazon, and even so, with the prediction of the construction of numerous dams in its hydrographic basin. We reinforce the importance of periodic flooding in these floodplains, for the maintenance of biodiversity and ecosystem services over time, and in this way, prevent biotic homogenization, and consequently, conserve these aquatic ecosystems.
    Description: Os ecossistemas de água doce estão passando por frequentes alterações nas suas condições naturais, influenciadas e aceleradas por atividades humanas. Esses processos são capazes de alterar o regime hidrológico e a composição das comunidades, deixando cada vez mais incerto o futuro da biodiversidade aquática. A construção de barramentos tem sido um dos principais responsáveis por modificações ambientais, como a redução de nutrientes, o aumento da transparência da água e a perda de biodiversidade em ecossistemas dulcícolas. O objetivo deste estudo foi analisar a dissimilaridade funcional e taxonômica da comunidade zooplanctônica e seus determinantes em resposta ao efeito do ciclo hidrológico (seca e chuva) em duas planícies de inundação altamente distintas, a planície do alto rio Paraná (rio com cascata de barramentos) e planície Amazônica. Foram coletadas 72 amostras (16 na seca e 16 na cheia na planície Amazônica e 20 na seca e 20 na cheia na palnície do alto rio Paraná) das comunidades de zooplâncton como variável resposta, de fitoplâncton como variável preditora de alimentação, de peixes como preditor de potenciais predadores e as variáveis limnológicas. Foram calculadas a diversidade β-Total e particionada nos componentes β-Repl e β-Rich em uma abordagem taxonômica e funcional, e espera-se que a heterogeneidade ambiental conduza a maiores valores de diversidade beta. Na sequência, foi calculada através das matrizes de distância geradas na beta funcional e taxonômica a análise de redundância baseada em distância (db-RDA) para avaliar quais os determinantes da diversidade beta. Assim, foi hipotetizado que as interações bióticas apresentarão relações mais fortes com a dissimilaridade zooplanctônica na seca e as variáveis limnológicas e o espaço na cheia. Foi encontrada uma maior heterogeneidade ambiental na planície Amazônica e também no período de seca. A diversidade beta funcional e taxonômica do zooplâncton apresentou uma relação semelhante entre as planícies e entre os períodoshidrológicos, representados pelo componente β-Repl, exceto pelo período de seca na planície do alto rio Paraná onde a diversidade funcional apresentou os menores valores, não detectado pela abordagem taxonômica. Os fatores que influenciaram a diversidade beta funcional e taxonômica zooplanctônica nas duas planícies de inundação foram bem distintos dependendo do período hidrológico, refletindo mais uma vez a diferença na heterogeneidade ambiental e na força da hidrodinâmica dentro de cada planície. A análise da distribuição das espécies e dos traços funcionais, e de quais variáveis estruturam essa distribuição é de extrema importância para analisar os processos e serviços ecossistêmicos, especialmente em ambientes impactados como a planície de inundação do alto rio Paraná, e uma planície tão biodiversa como a Amazônica e, mesmo assim, com previsão de construção de inúmeros barramentos em sua bacia hidrográfica. Reforça-se a importância da inundação periódica nessas planícies, para a manutenção da biodiversidade e dos serviços ecossistêmicos ao longo do tempo e, desta forma, prevenir a homogeneização biótica, e consequentemente, a conservação dos ecossistemas aquáticos.
    Description: PhD
    Keywords: Zooplâncton de água doce ; Comunidades, Ecologia de ; Diversidades beta taxonômica e funcional ; Planícies de inundação ; Floodplain ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::Y::Zooplankton ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::S::Species diversity
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 56pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 75
    facet.materialart.
    Unknown
    Relações filogenéticas em Geophagini (Acanthopterygii, Cichlidae), utilizando caracteres miológicos. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-05
    Description: Although several studies have dealt with the description of morphological characters in Cichlidae, usually aiming for phylogenetic inference, little attention has been given to their musculature. The complete striated musculature of a cichlid species, Geophagus sveni Lucinda, Lucena & Assis, was described for the first time, with illustrations of all muscles and a protocol for the dissection of specimens. The striated musculature of at least of species of each genus in tribe Geophagini, among other cichlids, was compared, and 98 characters were described with the purpose of analysing their relation with the group’s phylogeny. This character matrix was employed to produce two unconstrained phylogenetic analyses, one weighted and the other unweighted. The myological characters were mapped upon a pre-existing phylogenetic hypothesis, for understanding the correlation among the characters and trophic specialisations of each taxon. The conclusion is that Geophagini specialised in sifting substrate (winnowers) tend to present a few convergent adaptations, manifested in the shape and degree of development of muscles such as adductor mandibulae, levator arcus palatini, dilatator operculi, adductor branchialis 1 and obliqui ventrales 1–2. This study facilitates future investigations on the functions of the striated muscles in fishes and their role in the processes of adaptive radiation, i.e., functional diversification.
    Description: Apesar de diversos estudos terem tratado da descrição de caracteres morfológicos em Cichlidae, geralmente para fins de inferência filogenética, muito pouco se estudou sobre sua musculatura. Descreveu-se, pela primeira vez, a musculatura estriada completa de uma espécie de ciclídeo, Geophagus sveni Lucinda, Lucena & Assis, com ilustrações de todos os músculos e um protocolo para a dissecção de exemplares. Comparou-se a musculatura esquelética de pelo menos uma espécie de cada gênero da tribo Geophagini, dentre outros ciclídeos, e descreveram-se 98 caracteres com o propósito de analisar sua relação com a filogenia do grupo. Essa matriz de caracteres foi empregada para produzir duas análises filogenéticas sem restrição, uma com pesagem e outra sem pesagem. Mapearam-se os caracteres miológicos sobre uma hipótese filogenética pré-existente, para a compreensão da correlação entre os caracteres e as especializações tróficas de cada táxon. Conclui-se que os Geophagini especializados em peneirar o substrato (winnowers) tendem a apresentar algumas adaptações convergentes, manifestadas na forma e no grau de desenvolvimento de músculos como adductor mandibulae, levator arcus palatini, dilatator operculi, adductor branchialis 1 e obliqui ventrales 1–2. Este estudo possibilita futuras investigações acerca das funções dos músculos estriados em peixes e seu papel nos processos de irradiação adaptativa, i.e., diversificação funcional.
    Description: PhD
    Keywords: Geophagini (Acanthopterygii, Cichlidae) “cará” ; Peixes de água doce ; Filogenia ; Morfologia ; Musculatura esquelética ; ASFA_2015::F::Freshwater fish ; ASFA_2015::T::Taxonomy ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::M::Morphology (organisms) ; ASFA_2015::P::Phylogeny ; ASFA_2015::M::Musculoskeletal system
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 234pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 76
    facet.materialart.
    Unknown
    Predação e estruturação de habitat por macrófitas modificam a diversidade taxonômica e funcional do zooplâncton. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-06-28
    Description: In Neotropical rivers the predation by fish and the structuring of the habitat by macrophytes influence the dynamics of the zooplankton community, altering the richness and composition of species and the richness and functional composition of the zooplankton and thus the functioning of the ecosystem. We analyzed the influence of macrophytes bank structure and predation by forage fish species on taxonomic and functional zooplankton diversity, estimated by different diversity indices (taxonomic and functional richness, taxonomic beta diversity and functional beta diversity). Thus, we assume that different levels of macrophytes structure and fish predation will alter the taxonomic and functional composition of the zooplankton (alpha and beta) between the analyzed points. Beta diversity was split into two distinct components, turnover and nesting. The zooplankton species richness was positively associated with the macrophytes richness and the macrophytes diversity. In turn, the functional richness of zooplankton had a positive association with fish richness and macrophytes richness. For the variation of total taxonomic beta diversity of zooplankton, the Generalized Dissimilarity Modeling (GDM) explained 32.58% of the total among the predictor variables. The macrophytes biomass represented the taxonomic turnover. The variation in total functional beta diversity of the zooplankton explained 9.98% by the GDM model. The abundance of fish represented the functional nesting. Macrophytes structure represented the taxonomic components and predation represented the functional components. The limnological heterogeneity of the coastal region of the Bay River made possible the colonization by multispecies macrophytes banks, influencing the alteration of the fish and zooplankton community and the more heterogeneous the environmental conditions, the greater is the capacity of colonization of different species, which can present different functional traits. The results indicate the importance of maintaining heterogeneous locations, the need to preserve the tributaries in river floodplain systems as they serve as nursery for fish spawning and contribute to a greater richness of fish, which causes an increase in the functional diversity of zooplankton.
    Description: Em rios neotropicais a predação por peixes e a estruturação do habitat por macrófitas influenciam na dinâmica da comunidade zooplanctônica, alterando a riqueza e composição de espécies e a riqueza e composição funcional do zooplâncton e, assim, o funcionamento do ecossistema. Analisou-se a influência da estruturação dos bancos de macrófitas e a predação por espécies de peixes forrageiras sobre a diversidade taxonômica e funcional zooplanctônica, estimadas por diferentes índices de diversidade (riqueza taxonômica e funcional, diversidade beta taxonômica e diversidade beta funcional). Assim, supõe-se que diferentes níveis de estruturação por macrófitas e predação por peixes alterarão a composição taxonômica e funcional do zooplâncton (alfa e beta) entre os pontos analisados. A diversidade beta foi particionada em dois componentes distintos, o turnover e o aninhamento. A riqueza de espécies do zooplâncton associou-se de forma positiva com a riqueza de macrófitas e a diversidade de macrófitas. Por sua vez, a riqueza funcional do zooplâncton teve associação positiva com a riqueza de peixes e a riqueza de macrófitas. Para a variação da diversidade beta total taxonômica do zooplâncton, a Modelagem de Dissimilaridade Generalizada (GDM) explicou 32,58% do total dentre as variáveis preditoras. A biomassa de macrófitas representou o turnover taxonômico. A variação da diversidade beta total funcional do zooplâncton, explicou 9,98% pelo modelo da GDM. A abundância de peixes representou o aninhamento funcional. A estruturação por macrófitas representou os componentes taxonômicos e a predação representou os componentes funcionais. A heterogeneidade limnológica da região litorânea do rio Baía possibilitou a colonização por bancos de macrófitas multiespecíficos, influenciando na alteração da comunidade de peixes e de zooplâncton e quanto mais heterogêneas as condições ambientais, maior é a capacidade de colonização de diferentes espécies, que podem apresentar distintos traços funcionais. Os resultados indicam a importância da manutenção de locais heterogêneos, a necessidade de preservação dos tributários em sistemas rio-planície de inundação por servirem como berçário para desova de peixes e contribuir para uma maior riqueza de peixes, o que causa um aumento na diversidade funcional do zooplâncton.
    Description: Masters
    Keywords: Zooplâncton de água doce ; Riqueza taxonômica e funcional ; Diversidade beta ; Taxonomic richness ; Functional richness ; Beta diversity ; Nestedness ; Turnover ; Comunidades, Ecologia de ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::Y::Zooplankton ; ASFA_2015::M::Macrophytes ; ASFA_2015::T::Taxonomy ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::P::Predation
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 49pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 77
    facet.materialart.
    Unknown
    Effects of dam operation on stability, species interactions, and the mechanisms underlying the synchrony of fish in reservoirs. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-08-31
    Description: The construction of dams is among the main anthropogenic impacts in natural freshwater systems. The first consequence of impoundments is the formation of reservoirs upstream, which represents a completely new environment compared to the natural river. In addition to this primary impact, the variations in the reservoir water level may be considered another facet of disturbances. Although several studies investigated the processes that occur in reservoirs, there is a shortfall regarding the effects of the dam operation scheme on ecosystem health. Most dams are designed to operate under two almost contrasting schemes: storage (STR) and run-of-river (ROR). These alternative operation schemes result in very different temporal variations, with STR reservoirs presenting rapid fluctuations while ROR reservoirs have a relatively constant volume. Likewise, this difference in the temporal dynamics of water level likely affects the stability of these ecosystems. In order to investigate how the dam operation scheme could affect the temporal stability of freshwater ecosystems, we used the fish communities from two reservoirs in the Iguaçu River that operate under contrasting schemes. The hypothesis was that the STR reservoir would be less stable, considering the environmental heterogeneity created by frequent water level variations, and the interactions among species would be less important for the structure of the resident fish community. In the first approach, the focus was on stability in terms of the ability to resist and recover (i.e., resistance and resilience) to disturbances. In the second approach, empirical data and simulations were used to assess which mechanism (species interactions, environmental or demographic stochasticity) underlie the synchrony of fish communities. Contrary to the expectation, the results showed the ROR reservoir as less stable than the STR, and the mechanisms underlying species synchrony coincided between reservoirs but played opposite roles. More specifically, the temporal dynamics imposed by ROR operation may have weakened the species-environment relationships, which led to a less stable community. Although the results were consistent, they were only primary evidence and such cause-effect relationships between dam operation and its effects on ecosystem stability require further investigations.
    Description: A construção de barragens está entre os principais impactos antropogênicos em ambientes de água doce. A primeira consequência dos barramentos é a formação de um reservatório à montante, que representa um ambiente completamente modificado, em relação ao rio natural. Impactos secundários, como as variações no nível da água, também podem ser considerados outros tipos de distúrbio. Embora vários estudos investigaram os processos que ocorrem em reservatórios, existe uma lacuna a respeito dos efeitos do modo de operação da barragem sobre a estado dos ecossistemas. A maioria das barragens é projetada para operar sob dois modos: acumulação (ACU) e fio d’água (FDA). Esses modos alternativos resultam em variações temporais muito distintas, com reservatórios ACU apresentando flutuações rápidas, enquanto reservatórios FDA possuem volume relativamente constante. Do mesmo modo, essa diferença na dinâmica temporal do nível da água provavelmente afeta a estabilidade desses ecossistemas. A fim de investigar como o modo de operação da barragem pode afetar a estabilidade temporal dos ambientes de água doce, foram utilizadas comunidades de peixes de dois reservatórios do rio Iguaçu, que operam sob modos diferentes. A hipótese testada foi que o reservatório ACU seria menos estável, considerando a heterogeneidade ambiental criada pelas variações frequentes no nível da água, e as interações entre as espécies seriam menos importantes para a estrutura da comunidade de peixes. Na primeira abordagem, o foco foi na estabilidade em termos da habilidade em resistir e se recuperar (i.e., resistência e resiliência) aos distúrbios. Na segunda abordagem, dados empíricos e simulações foram utilizados para verificar quais mecanismos (interações entre espécies, ou estocasticidade ambiental/demográfica) seriam subjacentes à sincronia das comunidades de peixes. Ao contrário do esperado, os resultados mostraram que o reservatório FDA foi menos estável do que o reservatório ACU e os mecanismos subjacentes à sincronia das espécies coincidiram entre os reservatórios, mas com papéis opostos. Mais especificamente, a dinâmica temporal imposta pela operação do reservatório FDA provavelmente enfraqueceu as relações espécie-ambiente, o que levou a uma comunidade menos estável. Embora os resultados sejam consistentes, são apenas indícios primários e as relações de causa-e-efeito entre o modo de operação da barragem e a estabilidade dos ecossistemas requer investigações futuras.
    Description: PhD
    Keywords: Peixes de água doce ; Reservatórios de água doce ; Environmental stochasticity ; Reservatórios ; Comunidades, Ecologia de ; Competição interespecífica ; Impactos ambientais antropogênicos ; Manejo ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::N::Niches ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::I::Impacts ; ASFA_2015::C::Competition ; ASFA_2015::R::Reservoirs (water) ; ASFA_2015::S::Species diversity ; ASFA_2015::I::Interactions ; ASFA_2015::I::Impoundments
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 98pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 78
    facet.materialart.
    Unknown
    Aspectos ecológicos e taxonômicos da fauna ectoparasitária de Plagioscion squamosissimus (Heckel, 1840) (Sciaenidae) no rio Tapajós, Bacia Amazônica, Brasil. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-01
    Description: Plagioscion squamosissimus (Heckel, 1840) (Sciaenidae), known as “corvina” is a native species of Amazon basin and it is a model for studding their parasites. Intending to analyze ectoparasites ecological aspects, such as distribution and interactions, gills of twenty specimens were analyzed, from rio Tapajós, in the region of Santarém-PA, Brazil. Ecological analyzes considered distribution of parasites between host specimens and also microhabitats occupied by ectoparasites. Eighteen ectoparasites species were founded, fourteen monogenetic and four copepods. Considering species abundance, monogenetic were the dominant group and Euryhaliotrema thatcheri was the most abundant in all analyzed hosts. There was a significate correlation between some parasite species abundance and prevalence with total length and host condition factor. Each species of parasite presented an aggregate distribution pattern. The community of P. squamosissimus ectoparasites were interactive. Considering the distribution of the species in the gills, there was a significant difference in the composition between arches, segments and regions. It is suggested that this distribution is related to factors related to microhabitat, such as water flow and area available for fixation of parasites, as well as the structures of fixation of each species and interactions such as positive associations and competition. During the investigation of the material, specimens that differed from the species already described were founded, so three new monogenetic species were proposed, belonging to the genus Aetheolabes, Anakohnia and Euryhaliotrema, based on their morphological characteristics.
    Description: A corvina de água doce ou pescada branca, Plagioscion squamosissimus (Heckel, 1840) (Sciaenidae) se distribui pela bacia Amazônica e que como hospedeira, consiste em um modelo para o estudo de seus parasitas. Analisou-se os aspectos ecológicos da fauna ectoparasitária de P. squamosissimus, tais como a distribuição e as interações e entre as espécies, por meio das brânquias de vinte espécimes coletados no rio Tapajós, região de Santarém-PA. Considerou-se a distribuição de parasitas entre os espécimes de hospedeiros e também, a partir dos microhabitats que os ectoparasitas ocupavam nesses espécimes. Foram encontradas dezoito espécies de ectoparasitas, dentre os quais catorze monogenéticos e quatro copépodes. Em relação a abundância das espécies, os monogenéticos destacaram-se como grupo dominante e, dentre estas espécies, Euryhaliotrema thatcheri apresentou-se como a mais abundante em todos os hospedeiros analisados. Houve correlação da abundância e da prevalência de algumas espécies de parasitas com o comprimento total e o fator de condição dos hospedeiros. Cada espécie de parasita apresentou padrão de distribuição agregado. A comunidade de ectoparasitas de P. squamosissimus foi considerada interativa. Em relação à distribuição das espécies nas brânquias, houve diferença significativa na composição entre os arcos, segmentos e regiões. Sugere-se que esta distribuição se relaciona com fatores referentes ao microhabitat, como o fluxo de água e a área disponível para fixação dos parasitas, bem como as estruturas de fixação de cada espécie e também interações como associações positivas e competição. Durante a investigação do material, os espécimes encontrados diferiram das espécies previamente descritas, de modo que realizou-se a proposta de três novas espécies de monogenéticos pertencentes aos gêneros Aetheolabes, Anakohnia e Euryhaliotrema a partir de suas características morfológicas.
    Description: PhD
    Keywords: Fauna ectoparasitária ; Monogenea ; Copepoda ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::P::Parasites ; ASFA_2015::E::Ectoparasites ; ASFA_2015::E::Ectoparasitism
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 83pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 79
    facet.materialart.
    Unknown
    Simulated estuary-wide response of seagrass (Zostera marina) to future scenarios of temperature and sea level (2020)
    Frontiers Media
    Details
    Publication Date: 2022-10-27
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Scalpone, C. R., Jarvis, J. C., Vasslides, J. M., Testa, J. M., & Ganju, N. K. Simulated estuary-wide response of seagrass (Zostera marina) to future scenarios of temperature and sea level. Frontiers in Marine Science, 7, (2020): 539946, doi:10.3389/fmars.2020.539946.
    Description: Seagrass communities are a vital component of estuarine ecosystems, but are threatened by projected sea level rise (SLR) and temperature increases with climate change. To understand these potential effects, we developed a spatially explicit model that represents seagrass (Zostera marina) habitat and estuary-wide productivity for Barnegat Bay-Little Egg Harbor (BB-LEH) in New Jersey, United States. Our modeling approach included an offline coupling of a numerical seagrass biomass model with the spatially variable environmental conditions from a hydrodynamic model to calculate above and belowground biomass at each grid cell of the hydrodynamic model domain. Once calibrated to represent present day seagrass habitat and estuary-wide annual productivity, we applied combinations of increasing air temperature and sea level following regionally specific climate change projections, enabling analysis of the individual and combined impacts of these variables on seagrass biomass and spatial coverage. Under the SLR scenarios, the current model domain boundaries were maintained, as the land surrounding BB-LEH is unlikely to shift significantly in the future. SLR caused habitat extent to decrease dramatically, pushing seagrass beds toward the coastline with increasing depth, with a 100% loss of habitat by the maximum SLR scenario. The dramatic loss of seagrass habitat under SLR was in part due to the assumption that surrounding land would not be inundated, as the model did not allow for habitat expansion outside the current boundaries of the bay. Temperature increases slightly elevated the rate of summer die-off and decreased habitat area only under the highest temperature increase scenarios. In combined scenarios, the effects of SLR far outweighed the effects of temperature increase. Sensitivity analysis of the model revealed the greatest sensitivity to changes in parameters affecting light limitation and seagrass mortality, but no sensitivity to changes in nutrient limitation constants. The high vulnerability of seagrass in the bay to SLR exceeded that demonstrated for other systems, highlighting the importance of site- and region-specific assessments of estuaries under climate change.
    Description: This research was supported by the National Science Foundation Research Experience for Undergraduates Program (OCE-1659463), the Woods Hole Oceanographic Institution Summer Student Fellowship Program, the Barnegat Bay Partnership (through a US EPA Clean Water Act grant to Ocean County College; CE98212313), and the USGS Coastal and Marine Hazards/Resources Program. Although this project has been funded in part by the United States Environmental Protection Agency pursuant to a grant agreement with Ocean County College, it has not gone through the Agency’s publications review process and may not necessarily reflect the views of the Agency; therefore, no official endorsement should be assumed. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
    Keywords: Seagrass (Zostera) ; Climate change ; Spatial model ; Sea level rise ; Temperature ; North American Atlantic Coast ; Regional ; Eelgrass (Zostera marina)
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 80
    facet.materialart.
    Unknown
    Growth rates under low and high temperatures for Emiliania huxleyi in constant and fluctuating thermal environments (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Ehux growth rates under thermal variation
    Description: This dataset includes the growth rates under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments. Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/782888
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1538525
    Keywords: Thermal Performance Curves ; Growth Rates ; Emiliania huxleyi ; Climate change ; Calcification ; Elemental quotas
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 81
    facet.materialart.
    Unknown
    Intracellular elemental quotas under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Ehux physiology under thermal variation
    Description: Intracellular elemental quotas under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments. This dataset includes the growth rates under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments. Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/782901
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1538525
    Keywords: Thermal Performance Curves ; Growth Rates ; Emiliania huxleyi ; Climate change ; Calcification ; Elemental quotas
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 82
    facet.materialart.
    Unknown
    Continuous culture studies of possible climate change effects: Thalassiosira pseudonana CCMP1335 growth in nitrate-limited and nutrient-replete cultures (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Thalassiosira pseudonana CCMP1335 in nitrate-limited and nutrient-replete cultures
    Description: The marine diatom Thalassiosira pseudonana clone CCMP 1335 was grown in a continuous culture system on a 14:10 light-dark cycle under either nitrate-limited or nutrient-replete conditions, a photoperiod irradiance of either 50 or 300 micro-mol photons per square meter per second, partial pressures of either 400 or 1000 ppm CO2, and temperatures ranging from 5 to 32 degrees Celsius. Growth rates, photosynthetic rates, respiration rates, C:N ratios, C:Chlorophyll-a ratios, productivity indices, Fv/Fm ratios, and the initial slope and light-saturated asymptote of short-term photosynthesis-irradiance curves are reported. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/779368
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1536581
    Keywords: Climate change ; Phytoplankton ; Light ; Temperature ; CO2 partial pressure ; Acclimation
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 83
    facet.materialart.
    Unknown
    Growth rates for Emiliania huxleyi thermal response curve across 12 temperatures from 8.5-28.6C (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Ehux growth rates for thermal response curve
    Description: This dataset presents growth rates for Emiliania huxleyi thermal response curve across 12 temperatures from 8.5-28.6C.Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/782911
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1538525
    Keywords: Thermal Performance Curves ; Growth Rates ; Emiliania huxleyi ; Climate change ; Calcification ; Elemental quotas
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 84
    facet.materialart.
    Unknown
    Elemental stoichiometry for Emiliania huxleyi across a range of 12 temperatures from 8.5-28.6C (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Ehux elemental composition across thermal range
    Description: This dataset includes elemental stoichiometry for Emiliania huxleyi across a range of 12 temperatures from 8.5-28.6C. Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/782921
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1538525
    Keywords: Thermal Performance Curves ; Growth Rates ; Emiliania huxleyi ; Climate change ; Calcification ; Elemental quotas
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 85
    facet.materialart.
    Unknown
    Gill Net Catch Data in Bays along Texas Coast from 1986 to 2018 (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Gill Net Catch Data
    Description: Vertebrate caught with gill net in Sabine Lake, Galveston Bay, Matagorda Bay, San Antonio Bay, Aransas Bay, Corpus Christi Bay, Upper Laguna Madre, and Lower Laguna Madre from 1986 to 2018 (except in Sabine Lake sampling begun in 1986). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/828794
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1656923
    Keywords: Marine biodiversity ; Climate change ; Coastal ecosystems ; Fish diversity
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 86
    facet.materialart.
    Unknown
    Continuous culture studies of possible climate change effects: Synechococcus elongatus CCMP1629 growth in nitrate-limited and nutrient-replete cultures (2020)
    Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu
    Details
    Publication Date: 2022-10-31
    Description: Dataset: Synechococcus elongatus CCMP1629 in nitrate-limited and nutrient-replete cultures
    Description: The marine cyanobacterium Synechococcus elongatus clone CCMP1629 was grown in a continuous culture system on a 14:10 light-dark cycle under either nitrate-limited or nutrient-replete conditions, a photoperiod irradiance of either 50 or 300 micro-mol photons per square meter per second, partial pressures of either 400 or 1000 ppm CO2, and temperatures ranging from 20 to 45 degrees Celsius. Growth rates, photosynthetic rates, respiration rates, C:N ratios, C:Chlorophyll-a ratios, productivity indices, Fv/Fm ratios, and the initial slope and light-saturated asymptote of short-term photosynthesis-irradiance curves are reported. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/811093
    Description: NSF Division of Ocean Sciences (NSF OCE) OCE-1536581
    Keywords: Climate change ; Phytoplankton ; Light ; Temperature ; CO2 partial pressure ; Acclimation
    Repository Name: Woods Hole Open Access Server
    Type: Dataset
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 87
    facet.materialart.
    Unknown
    Soothsaying DOM: A current perspective on the future of oceanic dissolved organic carbon (2020)
    Frontiers Media
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Wagner, S., Schubotz, F., Kaiser, K., Hallmann, C., Waska, H., Rossel, P. E., Hansmann, R., Elvert, M., Middelburg, J. J., Engel, A., Blattmann, T. M., Catala, T. S., Lennartz, S. T., Gomez-Saez, G., V., Pantoja-Gutierrez, S., Bao, R., & Galy, V. Soothsaying DOM: A current perspective on the future of oceanic dissolved organic carbon. Frontiers in Marine Science, 7, (2020): 341, doi:10.3389/fmars.2020.00341.
    Description: The vast majority of freshly produced oceanic dissolved organic carbon (DOC) is derived from marine phytoplankton, then rapidly recycled by heterotrophic microbes. A small fraction of this DOC survives long enough to be routed to the interior ocean, which houses the largest and oldest DOC reservoir. DOC reactivity depends upon its intrinsic chemical composition and extrinsic environmental conditions. Therefore, recalcitrance is an emergent property of DOC that is analytically difficult to constrain. New isotopic techniques that track the flow of carbon through individual organic molecules show promise in unveiling specific biosynthetic or degradation pathways that control the metabolic turnover of DOC and its accumulation in the deep ocean. However, a multivariate approach is required to constrain current carbon fluxes so that we may better predict how the cycling of oceanic DOC will be altered with continued climate change. Ocean warming, acidification, and oxygen depletion may upset the balance between the primary production and heterotrophic reworking of DOC, thus modifying the amount and/or composition of recalcitrant DOC. Climate change and anthropogenic activities may enhance mobilization of terrestrial DOC and/or stimulate DOC production in coastal waters, but it is unclear how this would affect the flux of DOC to the open ocean. Here, we assess current knowledge on the oceanic DOC cycle and identify research gaps that must be addressed to successfully implement its use in global scale carbon models.
    Description: This work was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) project number 422798570. The Hanse-Wissenschaftskolleg and the Geochemical Society provided funding for the conference. Additional support was provided by the National Science Foundation OCE #1756812 to SW. TB acknowledges funding from ETH Zürich and JAMSTEC. JM was supported by the Netherlands Earth System Science Centre. SP-G was funded by COPAS Sur-Austral (CONICYT PIA APOYO CCTE AFB170006). GG-S acknowledges funding from DFG, DI 842/6-1.
    Keywords: Dissolved organic carbon ; Global carbon cycle ; Recalcitrance ; Isotopic probing ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 88
    facet.materialart.
    Unknown
    Editorial: advances in understanding marine heatwaves and their impacts (2020)
    Frontiers Media
    Details
    Publication Date: 2022-10-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Benthuysen, J. A., Oliver, E. C. J., Chen, K., & Wernberg, T. Editorial: advances in understanding marine heatwaves and their impacts. Frontiers in Marine Science, 7, (2020): 147, doi:10.3389/fmars.2020.00147.
    Description: Editorial on the Research Topic Advances in Understanding Marine Heatwaves and Their Impacts In recent years, prolonged, extremely warm water events, known as marine heatwaves, have featured prominently around the globe with their disruptive consequences for marine ecosystems. Over the past decade, marine heatwaves have occurred from the open ocean to marginal seas and coastal regions, including the unprecedented 2011 Western Australia marine heatwave (Ningaloo Niño) in the eastern Indian Ocean (e.g., Pearce et al., 2011), the 2012 northwest Atlantic marine heatwave (Chen et al., 2014), the 2012 and 2015 Mediterranean Sea marine heatwaves (Darmaraki et al., 2019), the 2013/14 western South Atlantic (Rodrigues et al., 2019) and 2017 southwestern Atlantic marine heatwave (Manta et al., 2018), the persistent 2014–2016 “Blob” in the North Pacific (Bond et al., 2015; Di Lorenzo and Mantua, 2016), the 2015/16 marine heatwave spanning the southeastern tropical Indian Ocean to the Coral Sea (Benthuysen et al., 2018), and the Tasman Sea marine heatwaves in 2015/16 (Oliver et al., 2017) and 2017/18 (Salinger et al., 2019). These events have set new records for marine heatwave intensity, the temperature anomaly exceeding a climatology, and duration, the sustained period of extreme temperatures. We have witnessed the profound consequences of these thermal disturbances from acute changes to marine life to enduring impacts on species, populations, and communities (Smale et al., 2019). These marine heatwaves have spurred a diversity of research spanning the methodology of identifying and quantifying the events (e.g., Hobday et al., 2016) and their historical trends (Oliver et al., 2018), understanding their physical mechanisms and relationships with climate modes (e.g., Holbrook et al., 2019), climate projections (Frölicher et al., 2018), and understanding the biological impacts for organisms and ecosystem function and services (e.g., Smale et al., 2019). By using sea surface temperature percentiles, temperature anomalies can be quantified based on their local variability and account for the broad range of temperature regimes in different marine environments. For temperatures exceeding a 90th-percentile threshold beyond a period of 5-days, marine heatwaves can be classified into categories based on their intensity (Hobday et al., 2018). While these recent advances have provided the framework for understanding key aspects of marine heatwaves, a challenge lies ahead for effective integration of physical and biological knowledge for prediction of marine heatwaves and their ecological impacts. This Research Topic is motivated by the need to understand the mechanisms for how marine heatwaves develop and the biological responses to thermal stress events. This Research Topic is a collection of 18 research articles and three review articles aimed at advancing our knowledge of marine heatwaves within four themes. These themes include methods for detecting marine heatwaves, understanding their physical mechanisms, seasonal forecasting and climate projections, and ecological impacts.
    Description: We thank the contributing authors, reviewers, and the editorial staff at Frontiers in Marine Science for their support in producing this issue. We thank the Marine Heatwaves Working Group (http://www.marineheatwaves.org/) for inspiration and discussions. This special issue stemmed from the session on Advances in Understanding Marine Heat Waves and Their Impacts at the 2018 Ocean Sciences meeting (Portland, USA).
    Keywords: Marine heatwaves ; Extreme events ; Ocean and atmosphere interactions ; Marine ecosystems ; Marine resources ; Climate change ; Climate variability ; Climate prediction
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 89
    facet.materialart.
    Unknown
    A complexidade do habitat e a variação individual na dieta e na morfologia de uma espécie de peixe associada à macrófitas. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-01
    Description: Generalist species can be composed of specialist individuals, who use a small part of the population's niche. This process is known as individual specialization and can involve changes in diet and morphology. In this study, we hypothesized that individual variations in the diet and morphology of fish associated with macrophytes are related to the habitat’s complexity and greater levels of individual specialization will be found in the intermediate levels of macrophyte biomass. Fish and macrophytes were sampled in 30 multispecific macrophytes stands with different biomasses in a 13.7 km stretch of the rio Baía (Paraná River floodplain). Habitat complexity was assessed using the biomass of aquatic macrophytes (five stands with low biomass, five with intermediate biomass and five with high biomass were selected) and the fish species used in this study was Moenkhausia forestii. The individuals' diet was evaluated using the volumetric method, and the morphology through 18 linear measurements and six area measurements. To assess individual specialization in the diet, the Specialization Index (IS) and the NODF nesting index were used. Individual morphological specialization was assessed using ecomorphological diversity for each level of macrophyte biomass. Correlations between diet and morphology were assessed using the Mantel test. IS and NODF values indicated greater individual specialization in the diet in macrophytes stands with low biomass. The greatest individual morphological specialization was found in macrophytes stands with intermediate biomasses. The Mantel test showed that there was no significant correlation between diet and morphology. The individual specialization of M. forestii diet is related to the increase in competition, mainly intraspecific, intensified by the low availability of resources in low biomass stands. Morphological specialization, in turn, is related to greater availability and accessibility to resources within the intermediate biomass stands, where there are ideal conditions for increasing richness and abundance of resources and little structural complexity when compared to high biomass stands.
    Description: Espécies generalistas podem ser compostas por indivíduos especialistas, que utilizam uma pequena parte do nicho da população. Este processo é conhecido como especialização individual e pode envolver mudanças na dieta e na morfologia. Investigou-se a hipótese de que variações individuais na dieta e na morfologia de peixes associados à macrófitas estão relacionadas à complexidade do habitat e que maiores níveis de especialização individual serão encontrados nos níveis intermediários de biomassa de macrófitas. Foram amostrados peixes e macrófitas em 30 bancos multiespecíficos de macrófitas com diferentes biomassas em um trecho de 13,7 km de extensão do rio Baía (planície de inundação do rio Paraná). A complexidade do habitat foi medida por meio da biomassa das macrófitas aquáticas (selecionou-se cinco bancos com biomassas baixas, cinco com biomassas intermediárias e cinco com biomassas altas) e a espécie de peixe utilizada foi Moenkhausia forestii. Analisou-se a dieta dos indivíduos mediante o método volumétrico e a morfologia mediante 18 medidas lineares e seis medidas de área. Para avaliar a especialização individual na dieta utilizou-se o Índice de Especialização (IS) e o Índice NODF de aninhamento. A especialização individual morfológica foi avaliada por intermédio da diversidade ecomorfológica para cada nível de biomassa de macrófitas. As correlações entre a dieta e a morfologia foram avaliadas por meio de um teste de Mantel. Os valores de IS e NODF indicaram maior especialização individual na dieta em bancos de macrófitas com baixas biomassas. A maior especialização morfológica individual foi verificada em bancos de macrófitas com biomassas intermediárias. O teste de Mantel mostrou que não houve correlação significativa entre a dieta e a morfologia. A especialização individual da dieta de M. forestii está relacionada com o aumento da competição, principalmente intraespecífica, intensificada pela baixa disponibilidade de recursos nos bancos de baixas biomassas. A especialização morfológica por sua vez está relacionada com a maior disponibilidade e acessibilidade aos recursos dentro dos bancos de biomassas intermediárias, onde existem condições ideais para o aumento da riqueza e abundância de recursos e pouca complexidade estrutural quando comparado aos bancos de biomassa alta.
    Description: Masters
    Keywords: Populações, Ecologia de ; Ecologia trófica ; Macrófitas aquáticas ; Especialização individual ; Indivíduos da mesma espécie ; Complexidade estrutural ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::A::Aquatic plants ; ASFA_2015::M::Macrophytes ; ASFA_2015::P::Population dynamics ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::P::Population structure ; ASFA_2015::T::Trophic levels
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 38pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 90
    facet.materialart.
    Unknown
    Sensoriamento remoto orbital para o estudo das interações ambiente-ictiofauna em um reservatório Neotropical. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-05
    Description: The differential distribution of productivity in reservoirs has consequences for the fish assemblage, influencing spatially in its distribution, along a longitudinal gradient. Following the hypothesis that the spatiotemporal dynamics of chlorophyll a and turbidity influence the distribution of the fish assemblage in the Sobradinho reservoir, BA, three predictions were tested: i) Whether the spatiotemporal variations of these variables, determined by digital processing of remote sensing images, follow the spatial zoning pattern described in the literature, for large reservoirs; ii) Whether with the increase in distance, in kilometers, from the collection points to the dam, there is an increase in the total abundance of fish; and iii) If, with the increase in productivity, represented by higher concentrations of chlorophyll a and turbidity, there is an increase in the abundance of fish (total or by trophic guild). The sampling was distributed in five periods, between April 2008 and July 2009, with at least one collection being carried out in each zone of the reservoir, fluvial, transition and lake, in each period. Bands 2 and 3 of scenes from the Landsat-5 satellite were selected, in which the chosen limnological variables show their peak of reflection. With the values of the collections in situ and the reflectance of the scenes, an interpolation was performed and, later, thematic maps of each of the variables were elaborated. The chlorophyll a and turbidity values of the ichthyofauna collection points were extracted from the interpolations. To analyze the existence of the longitudinal gradient, Spearman correlation analyses were performed between the value of the limnological variables and the distance from the collection point to the dam, obtained by extracting a longitudinal profile of the reservoir. To search for associations between limnological variables and ichthyofauna, Spearman's correlation analyses were performed with the value of the variables and total abundance and by trophic guilds. Also, the analyses were carried out dividing the collection points according to the reservoir area and the rainfall regime (dry and full). The Sobradinho reservoir showed a pattern of productivity zoning consistent with the typical pattern of large reservoirs. This zoning had a strong association with the distribution of fish abundance in the Sobradinho reservoir. There was an association between the abundance of fish in the lake area and the seasonal increase in productivity, with a remarkable decrease in abundance during the dry months and an increase in abundance during the floods. However, in the river zone, excess turbidity acted as a limiting factor. High values of this variable, also showing a greater flow of water, may have favored the dispersion of organisms to places of lesser environmental stress, reducing the abundance of fish in this region during floods. However, in general, the fluvial zone showed the highest abundances, exhibiting the well-known fluvial〉 transition〉 lacustrine pattern. The presence of favorable characteristics in the river zone, such as seasonal flooding and greater environmental heterogeneity, may have contributed to this result.
    Description: A distribuição diferencial da produtividade em reservatórios apresenta consequências sobre a assembleia de peixes, influenciando espacialmente na sua distribuição, ao longo de um gradiente longitudinal. Seguindo a hipótese de que as dinâmicas espaço-temporais de clorofila a e turbidez têm influência na distribuição da assembleia de peixes no reservatório de Sobradinho, BA, foram testadas três predições: i) Se as variações espaço-temporais destas variáveis, determinadas por processamento digital de imagens de sensoriamento remoto, seguem o padrão espacial de zonação descrito na literatura, para grandes reservatórios; ii) Se com o aumento da distância, em quilômetros, dos pontos de coleta em relação à barragem há incremento na abundância total de peixes; e iii) Se com o aumento da produtividade, representada por maiores concentrações de clorofila a e turbidez, há incremento na abundância de peixes (total ou por guilda trófica). A amostragem foi distribuída em cinco períodos, entre abril de 2008 e julho de 2009, sendo realizada pelo menos uma coleta em cada zona do reservatório, fluvial, transição e lacustre, em cada período. Selecionou-se as bandas 2 e 3 de cenas do satélite Landsat-5, nas quais as variáveis limnológicas escolhidas apresentam seu pico de reflexão. Com os valores das coletas in situ e a reflectância das cenas foi realizada uma interpolação e, posteriormente elaborou-se mapas temáticos de cada uma das variáveis. Os valores de clorofila a e turbidez dos pontos de coleta da ictiofauna foram extraídos das interpolações. Para analisar a existência do gradiente longitudinal, realizou-se análises de correlação de Spearman entre o valor das variáveis limnológicas e a distância do ponto de coleta em relação à barragem, obtidos através da extração de um perfil longitudinal do reservatório. Para buscar associações entre as variáveis limnológicas e a ictiofauna realizou-se análises de correlação de Spearman com o valor das variáveis e abundância total e por guilda trófica. Também, efetuou-se as análises dividindo os pontos de coleta de acordo com a zona do reservatório e com o regime pluviométrico (seca e cheia). O reservatório de Sobradinho apresentou um padrão de zonação de produtividade condizente com o padrão típico de grandes reservatórios. Esta zonação teve forte associação com a distribuição da abundância de peixes no reservatório de Sobradinho. Foi evidenciada uma associação entre a abundância de peixes da zona lacustre e o incremento sazonal da produtividade, sendo notável a diminuição da abundância durante os meses secos e o incremento desta durante as cheias. No entanto, na zona fluvial, o excesso de turbidez agiu como um fator limitante. Valores altos dessa variável, evidenciando também maior fluxo d’água, podem ter favorecido a dispersão dos organismos para locais de menor stress ambiental, diminuindo a abundância de peixes nesta região durante as cheias. Entretanto, em geral, a zona fluvial apresentou as maiores abundâncias, exibindo o conhecido padrão fluvial 〉 transição 〉 lacustre. A presença de características favoráveis na zona fluvial, como inundação sazonal e maior heterogeneidade ambiental, podem ter contribuido para esse resultado.
    Description: Masters
    Keywords: Ictiofauna de água doce ; Sensoriamento remoto orbital (SR) ; Reservatórios ; Variáveis limnológicas ; Gradiente longitudinal ; ASFA_2015::I::Ichthyofauna ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::R::Reservoirs (water) ; ASFA_2015::V::Variability ; ASFA_2015::L::Limnology ; ASFA_2015::R::Remote sensing
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 45pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 91
    facet.materialart.
    Unknown
    Abordagem multimétrica na avaliação da integridade ecológica : fundamentos conceituais e aplicações. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-05
    Description: The use of multimetric indices (MMIs) to assess ecological conditions in aquatic environments has been applied globally. These indices are practical tools that incorporate various biotic metrics at different levels of biological organization. However, criticism has been directed to the use of MMIs, especially regarding the methodological criteria applied in the process such as related to metric selection and scoring and identification of reference conditions that consider all sources of ecological integrity disturbance. A review of the scientific literature was carried out to evaluate processes of creation and validation of MMIs worldwide. The criteria used by scientists to identify reference conditions, metric selection and scoring, the main metrics globally used in MMIs, and the challenges in applying these indices were verified. It was identified whether nonnative species have been considered as a source of degradation of ecological integrity in the MMIs application. The results indicated that there are no common criteria for determining reference conditions, for metric selection and scoring, which makes it difficult to compare different programs and regions, and to develop or improve future MMIs. The results showed that metrics related to species richness were most frequently used in MMIs applied worldwide, thus, it represents a consistent response pattern in the assessment of ecological conditions. The results also indicate that differentiating natural variability from anthropogenic impacts was evidenced as the major challenge in the MMIs creation and application. The review of the scientific literature indicated that biological invasions are neglected in ecological integrity assessments, as nonnative species are rarely considered as a disturbing factor in identifying reference conditions and species origin metrics are not widely used in MMIs. The results presented in this review may promote the advancement and improvement of MMIs as bioassessment tools.
    Description: O uso de índices multimétricos (MMIs) para avaliação das condições ecológicas em ambientes aquáticos tem sido aplicado globalmente. Estes índices são ferramentas práticas que incorporam várias métricas bióticas em diferentes níveis de organização biológica. No entanto, críticas têm sido endereçadas ao uso de MMIs, especialmente em relação aos critérios metodológicos empregados no processo, como a seleção e pontuação de métricas e identificação de condições de referência que considerem todas as fontes de perturbação da integridade ecológica. Efetuou-se uma revisão de literatura científica a fim de avaliar processos de criação e validação de MMIs em todo o mundo. Verificou-se os critérios usados pelos cientistas para identificação de condições de referência, seleção e pontuação de métricas, as principais métricas usadas globalmente nos MMIs e os desafios na aplicação desses índices. Foi verificado se espécies não nativas têm sido consideradas como fonte de degradação da integridade ecológica na aplicação de MMIs. Os resultados obtidos indicaram que não existem critérios comuns para determinação das condições de referência e seleção e pontuação de métricas, o que dificulta a avaliação comparável entre diferentes programas e regiões e desenvolvimento ou aprimoramento de futuros MMIs. Os resultados mostraram que as métricas de riqueza de espécies foram as mais frequentemente usadas nos MMIs aplicados em todo o mundo, representando, assim, um padrão de resposta consistente na avaliação das condições ecológicas. Os resultados obtidos também sugerem que diferenciar a variabilidade natural dos impactos antropogênicos foi evidenciado como o maior desafio na criação e aplicação de MMIs. A revisão da literatura científica indicou que invasões biológicas são negligenciadas em avaliações de integridade ecológica, pois espécies não nativas são raramente consideradas como fator de perturbação na identificação de condições de referência e métricas de origem das espécies não são amplamente empregadas nos MMIs. Os resultados apresentados nessa revisão podem promover o avanço e aprimoramento dos MMIs como ferramentas de bioavaliação.
    Description: PhD
    Keywords: Ecossistemas de água doce ; Biomonitoramento ; Invasões biológicas ; Indicadores biológicos ; Índice de Integridade Biótica ; Seleção de métricas ; Integridade ecológica ; Indicadores ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::E::Ecosystems ; ASFA_2015::B::Bioindicators ; ASFA_2015::I::Indigenous species
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 92pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 92
    facet.materialart.
    Unknown
    Nematoides como indicadores de alterações ambientais em um rio com diferentes níveis de impacto antropogênico. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-02
    Description: Changes in the biodiversity of parasites communities can be used as indicators of the healthy ecosystem as they reflect environmental impacts through their responses to changes in habitat. Thus, the aim of the study was to investigate the potential use of parasites from Geophagus brasiliensis as bioindicators of environmental changes. Three sample points were determined of rio Iguaçu with different degrees of environmental impact. Among 69 specimes analyzed of G. brasiliensis, 32 (46.3%) were parasitized by at least one parasite. A total of 56 specimens of endoparasites belonging to the phylum Nematoda were collected. The abundance of nematode species was significantly higher in fishes collected in point 3 (Kruskal-Wallis2;69 = 8.62; p = 0.01) and species composition between points were significantly different (F = 6.95, p = 0.002). There was no significant difference in relative condition factor (Kn) of G. brasilienses between the points (F2;66 = 2.54; p = 0.08) there was no correlation in Kn and abundance of nematodes (rs = 0.1; p = 0.4). The lower abundance of nematodes was observed in point 1 (critically degraded), due to this environment showing changes in abiotic factors, represented in the relatively high values of conductivity and phosphorus when compared with points 2 and 3 (moderately degraded).The results obtained in the present study indicate that the parasitic community of G. brasiliensis is characterized by low diversity in polluted locations, thus the absence of certain species of parasites and the occurrence of nematode species demonstrated a variation in response to the pollution gradient.
    Description: Alterações na biodiversidade de comunidades parasitárias são utilizadas como indicadoras da saúde de sistemas ecológicos, pois refletem impactos ambientais mediante suas respostas às alterações no habitat. Investigou-se o potencial uso de nematoides de Geophagus brasiliensis como indicadores de alterações ambientais mediante o registro de sua presença e ausência. Foram determinados três pontos amostrais no rio Iguaçu com diferentes graus de impacto ambiental. Entre os 69 espécimes de G. brasiliensis analisados, 32 (46,3%) estavam parasitados por pelo menos um parasita. Um total de 56 espécimes de endoparasitas pertencentes a Nematoda foram coletados. A abundância de espécies de nematoides foi significativamente maior em peixes coletados no ponto 3 (Kruskal-Wallis 2;69 = 8,62; p = 0,01) e a composição das espécies entre os pontos foram significativamente diferentes (F = 6,95, p = 0,002). Não houve diferença significativa no fator de condição relativo (Kn) de G. brasiliensis entre os pontos (F2;66 = 2,54; p = 0,08) e na correlação entre o Kn e a abundância de nematoides (rs = 0,1; p = 0,4). A menor abundância foi verificada no ponto 1 (criticamente degradado), devido a esse ambiente apresentar alterações nos fatores abióticos e na estrutura biológica, quando comparado com os pontos 2 e 3 (moderadamente degradados). Os resultados obtidos indicam que a comunidade parasitária de G. brasiliensis é caracterizada por baixa diversidade em locais poluídos, portanto a ausência de certas espécies de parasitas e a ocorrência de espécies de nematoides demonstraram uma variação em resposta ao gradiente de poluição.
    Description: Masters
    Keywords: Peixes de água doce ; Ictioparasitologia de água doce ; Ecotoxicologia aquática ; Rio impactado ; Parasitas ; Ecotoxicologia ; Bioindicadores ; ASFA_2015::F::Freshwater fish ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::P::Parasites ; ASFA_2015::E::Ecotoxicology ; ASFA_2015::B::Bioindicators ; ASFA_2015::I::Impacts
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 26pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 93
    facet.materialart.
    Unknown
    Drivers of spatio-temporal dissimilarity in community composition: temporal changes in land use and environmental heterogeneity. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-02
    Description: Biodiversity encompasses multiple aspects or facets changing in space and time. Before a loss of biodiversity in response to anthropogenic impacts it is of the utmost importance to determine what facets of biodiversity are altered and the determinants of such changes. By using information from species abundance, their evolutionary relatedness, and ecological traits we determine how the dissimilarity in composition of fish communities is influenced by temporal changes in land use and changes in environmental heterogeneity across space. In the first approach, we can see that changes in land use over time affected mainly the substitution of evolutionary lineages and functional traits. In the second approach, we find evidence of taxonomic and functional homogenization over time, likely following a decrease in diversity of traits related to habitat use. Furthermore, we found that ecological traits contributed differently to the changes in functional composition as well in their response to environmental heterogeneity. These results support recently evidence showing that anthropogenic impacts are driving changes in biological communities through a taxonomic and functional homogenization.
    Description: A biodiversidade está constituída por múltiplos aspectos ou facetas que mudam no espaço e tempo. Ante um cenário de perda de diversidade em resposta a impactos antropogênicos é urgente determinar quais aspectos da biodiversidade estão sendo alterados e os determinantes de tais mudanças. Usando informação de abundância de espécies, suas relações evolutivas e características ecológicas, determinamos como dissimilaridade da composição entre comunidades de peixes é influenciada por mudanças no uso da terra ao longo do tempo e mudanças da heterogeneidade ambiental no espaço. Na primeira abordagem, podemos ver que ao longo do tempo as mudanças no uso da terra afetam principalmente a substituição de linhagens evolutivas e características ecológicas. Na segunda abordagem, encontramos evidência de que as comunidades estão sendo homogeneizadas taxonômica e funcionalmente ao longo do tempo, provavelmente devido à perda de diversidade em características relacionadas ao uso de habitat. Ademais, encontramos que as características ecológicas contribuem de forma diferente para as mudanças na composição funcional e apresentam diferenças na resposta à heterogeneidade ambiental. Esses resultados suportam evidências de que impactos antropogênicos estão levando a mudanças nas comunidades biológicas, as quais estão tendendo a perder diversidade mediante homogeneização taxonômica e funcional
    Description: PhD
    Keywords: Peixes de água doce ; Comunidades, Ecologia de ; Impactos ambientais antropogênicos ; Mudanças espaciais e temporais ; Diversidades funcional e filogenética ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::L::Land use ; ASFA_2015::P::Phylogenetics ; ASFA_2015::F::Functional analysis ; ASFA_2015::E::Ecological diversity ; ASFA_2015::T::Temporal variations ; ASFA_2015::T::Taxonomy ; ASFA_2015::E::Environmental impact
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 89pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 94
    facet.materialart.
    Unknown
    Variáveis relacionadas com a distribuição regional, dominância e estruturação de comunidades de peixes em riachos. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-02
    Description: Different ecological processes (e.g., rescue effect, environmental filtering, limiting similarity and dispersal) shape the structure of ecological communities. These processes, which are related to the theories of metapopulation and metacommunities, guided this study. For this purpose, data from fish communities in streams in the Upper Araguaia river basin (Mato Grosso and the Goiás States, Brazil) were used. It was observed that the regional distribution of fish species was modelled according to niche attributes (position and breadth), body size, trophic position, and swimming capacity. The results indicated that average abundance, niche position and niche amplitude predict the regional distribution of the species. Taken together, these results suggest the importance of metapopulation dynamics and niche-based processes explaining the regional distribution of species in the studied system. At another time, it was tested whether the abundance of subordinate species (i.e., any species that are not dominant in a local community) was correlated with the functional distance between dominant and subordinate species. In the results, a negative relationship between these quantities and that the subordinate species had larger body sizes compared to the dominant species in the local communities. These results also suggest that species filtering is more important than the interspecific competition to explain the patterns of species abundance distribution. In this study, was analyzed the relative importance of local environmental, landscape and spatial variables in structuring fish communities in streams of “veredas” (small wetlands in the Cerrado). The local environmental variables, after controlling the effect of space, were clearly more important than those obtained at the landscape scale. In view of the observations, it is concluded that the use of landscape data, in studies seeking environmental correlates of local community structure, should not occur at the expense of obtaining local variables (mainly those related to the habitat structure). The results of the three investigations in this study shown the predominant role of local environmental filters in the structuring of the fish communities analyzed. Species with high niche amplitude tend to have wide regional distributions and small-bodied ones tend to be locally dominant.
    Description: Diversos processos ecológicos, tais como efeito resgate, filtragem ambiental, similaridade limitante e dispersão atuam na estruturação das comunidades. Esses processos, relacionados às teorias de metapopulação e metacomunidades, direcionaram este estudo. Para tanto, dados de comunidades de peixes em riachos do Alto da bacia do rio Araguaia (estados do Mato Grosso e Goiás, Brasil) foram utilizados. Foi observado que a distribuição regional das espécies de peixes em função de atributos do nicho (posição e amplitude), tamanho do corpo, posição trófica e capacidade natatória. Observou-se que apenas a abundância média, a posição de nicho e a amplitude de nicho predizem a distribuição regional das espécies. Em conjunto, esses resultados indicam a importância da dinâmica metapopulacional e de processos baseados no nicho para explicar a distribuição regional das espécies de peixes de riachos do Cerrado. Em outro momento, foi testado se a abundância de espécies subordinadas (i.e., quaisquer espécies que não são dominantes numa comunidade local) estava correlacionada com a distância funcional entre espécies dominantes e subordinadas. Nos resultados, encontrou-se uma relação negativa entre essas quantidades e que as espécies subordinadas apresentavam maiores tamanhos corpóreos em comparação com as espécies dominantes nas comunidades locais. Esses resultados mostram que a filtragem de espécies é mais importante que a competição interespecífica para explicar a distribuição da abundância entre as espécies. Neste estudo, foi analisada a importância relativa de variáveis ambientais locais, da paisagem e espaciais na estruturação de comunidades de peixes de riachos de veredas (pequenas áreas úmidas do Cerrado). As variáveis ambientais locais, após controlar o efeito do espaço, foram claramente mais importantes que aquelas obtidas na escala da paisagem. Diante das observações, conclui-se que a obtenção de dados de paisagem, em estudos que buscam variáveis ambientais relacionadas com a estruturação de comunidades locais, não deve ocorrer em detrimento da obtenção de variáveis locais (principalmente aquelas relacionadas com a estruturação dos habitats). Os resultados das três investigações deste estudo mostram o papel preponderante de filtros ambientais locais na estruturação das comunidades de peixes em riachos do Cerrado. Espécies de peixes com maiores amplitudes de nicho tendem a apresentar maiores distribuições regionais e espécies com menores tamanhos corpóreos tendem a ser localmente dominantes.
    Description: PhD
    Keywords: Peixes de riachos de cerrado ; Ecologia funcional ; Peixes de riachos de água doce ; Comunidades, Ecologia de ; Escala espaço-temporal ; Diversidade funcional ; Variáveis ambientais ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::S::Stream ecology ; ASFA_2015::F::Functional analysis ; ASFA_2015::N::Niches ; ASFA_2015::D::Dispersion ; ASFA_2015::A::Abundance ; ASFA_2015::F::Filters
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 105pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 95
    facet.materialart.
    Unknown
    A diversidade de macrófitas altera a comunidade de invertebrados e a dieta de peixes. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-09-07
    Description: The diversity of aquatic macrophytes provides different local conditions, containing more microhabitat than homogeneous systems, thus supporting diverse biotic communities. Considering that the diversity of these plants can affect the invertebrate community and, consequently, the associated fish diet, this study assessed the influence of macrophyte diversity on the abundance, richness, and diversity of invertebrates, and the diet of Moenkhausia forestii. Fish, invertebrates, and macrophytes were sampled in macrophyte stands with different diversities, distributed along with a 14 km extension of the coastal region of Rio Baía (Upper Paraná River floodplain). The stands were separated into low, medium and high diversity, and they all had biomass that did not differ significantly. The invertebrates associated with the macrophytes and those consumed by M. forestii were identified and counted. Differences in abundance, richness, and diversity of invertebrates between levels of macrophyte diversity (low, medium and high) were tested using an ANOVA. Differences in the composition of the M. forestii diet were tested using a PERMANOVA, and feeding selectivity was calculated using the Ivlev index. Richness, diversity, and abundance of invertebrates were greater in high diversity macrophyte stands, however, for abundance, there was no significant difference between the levels of macrophyte diversity. The diet of M. forestii differed significantly between stands, and aquatic plants were the most used resource in low diversity. Invertebrates were dominant in high diversity, while aquatic plants and invertebrates were important in medium diversity of macrophytes. These results indicate that invertebrate communities were influenced by the diversity of macrophytes since richer and more diverse communities were also associated with more diverse stands of these plants. Changes observed in the diet of M. forestii were also associated with the diversity of macrophytes. In a scenario where involving changes in the attributes of these plants, and these stands become dominated by one or a few species of macrophytes, it is expected that this will reflect on other trophic levels, even at a local scale.
    Description: A diversidade de macrófitas aquáticas proporciona condições locais distintas, de modo a conter mais micro-habitat do que sistemas homogêneos, sustentando assim comunidades associadas diversas. Considerando que a diversidade destas plantas pode influenciar a comunidade de invertebrados e, consequentemente, a dieta de peixes associados, este estudo avaliou a influência da diversidade de macrófitas sobre a abundância, riqueza e diversidade de invertebrados, e sobre a dieta de Moenkhausia forestii. Peixes, invertebrados e macrófitas foram amostrados em bancos de macrófitas com diferentes diversidades, distribuídos ao longo de 14 km de extensão da região litorânea do rio Baía (planície de inundação do alto rio Paraná). Os bancos de macrófitas foram categorizados em diversidade baixa, média e alta, e todos apresentaram biomassa que não diferiram significativamente. Os invertebrados associados à macrófitas e os consumidos por M. forestii foram identificados e contados. Diferenças na abundância, riqueza e diversidade de invertebrados entre os níveis de diversidade de macrófitas (baixa, média e alta) foram testadas por uma ANOVA. Diferenças na composição da dieta de M. forestii entre os níveis de diversidade foram avaliadas por uma PERMANOVA. A riqueza, a diversidade e a abundância de invertebrados foram maiores em bancos de macrófitas com maior diversidade, porém para a abundância não houve diferença significativa entre os níveis de diversidade de macrófitas. A dieta de M. forestii diferiu significativamente entre os bancos, sendo que vegetal foi o recurso mais utilizado em baixa diversidade de macrófitas, invertebrado foi dominante em alta diversidade e vegetal e invertebrado foram importantes em média diversidade de macrófitas. Estes resultados indicam que as comunidades de invertebrados foram influenciadas pela diversidade de macrófitas, visto que comunidades mais ricas e diversas estiveram também associadas a bancos mais diversos destas plantas. As alterações constatadas na dieta de M. forestii também estiveram associadas à diversidade de macrófitas. A espécie passou de uma dieta onívora, em bancos de baixa diversidade, para uma dieta invertívora em bancos com alta diversidade de macrófitas. Assim, em um cenário onde haja mudanças nos atributos dessas plantas, e esses bancos passem a ser dominados por uma ou poucas espécies de macrófitas, é esperado que isso se reflita para os outros níveis tróficos, ainda que em uma escala local.
    Description: Masters
    Keywords: Macrófitas aquáticas ; Comunidades, Ecologia de ; Ecologia trófica ; Diversidade ; Peixes ; Alimentação ; Nicho ; Amplitude ; ASFA_2015::M::Macrophytes ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::E::Ecological diversity ; ASFA_2015::E::Ecology ; ASFA_2015::T::Trophic levels ; ASFA_2015::N::Niches ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::I::Invertebrate zoology
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 32pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 96
    facet.materialart.
    Unknown
    A diversidade funcional da assembleia de peixes em uma planície de inundação Neotropical: variações com eventos de El Niño Oscilação Sul (ENSO). (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-04
    Description: El Niño Southern Oscillation (ENSO) is a natural phenomenon that generates El Niño and La Niña events worldwide. Among the consequences caused by this climatic fluctuation, there are changes in the rainfall regime, which can trigger in times of extreme drought or extreme flood in freshwater environments, such as floodplains. The floodplain flood phases cause homogenization between the different environments, which also cause the homogenization of the fish assemblage in these floodplains. Among the rivers affected by ENSO is the Rio Paraná and the floodplain associated with its upper stretch, the upper Rio Paraná floodplain (UPRF). We aimed to study if El Niño phenomena change the functional diversity of fish in the floodplain between different environments, lakes and rivers. The results answered the hypotheses that: 1. El Niño events intensify floods in UPRF and, consequently, promote a functional homogenization of the fish assemblage; 2. Different functional guilds will be favored in times of El Niño or La Niña. The measurement of ENSO was obtained by the Oceanic Niño Index (ONI), while the hydrometric level of the upper Rio Paraná was obtained by daily measurement on a hydrometric ruler. The fish were collected with gillnets in different environments of the floodplain, lakes and rivers, being grouped in reproductive and trophic guilds, used to calculate indices of functional diversity. It was tested how ONI affects the hydrometric level of the upper Rio Paraná (Pearson's correlation); how ENSO affects the functional composition of floodplain fish (PCoA; PERMANOVA), as well as the effect of homogenization; which functional guilds are favored in El Niño or La Niña events and whether there is an additive effect of ONI and hydrometric level on the functional composition of the floodplain fish. The hydrometric level presented a positive correlation with ONI, indicating that El Niño events cause flooding in the upper Paraná River, while La Niña drought. The effect of El Niño's functional homogenization on fish was more visible in lakes, with rivers being less affected by ENSO, and floods were not intense enough to homogenize these two types of environment, this may be the same for other floodplains where ENSO acts in the same way. Fish with parental care and invertivores were favored in El Niño events, while herbivorous and piscivorous fish were favored in La Niña events. Migratory fish appears to respond one year after these climatic events, as they have a long-life cycle. The additive effect of ENSO and hydrometric level on the functional composition wasn’t found, because other regional and local factors can influence this interaction. However, even with these factors, the fish assemblage from the floodplain still responds to these climatic fluctuations, being more homogeneous in El Niño events than in La Niña events.
    Description: El Niño Oscilação Sul (El Niño Southern Oscillation – ENSO) é um fenômeno natural que gera eventos de El Niño e La Niña no mundo todo. Dentre as consequências causadas por essa oscilação climática, existem alterações no regime pluviométrico, que podem desencadear em épocas de extrema seca ou extrema cheia em ambientes de água doce, como as planícies de inundação. As fases de cheia de planícies de inundação causam uma homogeneização entre os diferentes ambientes, o que também causa a homogeneização da assembleia de peixes dessas planícies. Dentre os rios afetados por ENSO encontra-se o rio Paraná e a planície de inundação associada ao seu trecho superior, a planície de inundação do alto rio Paraná (PIARP). Estudou-se o fenômeno de El Niño e por meio da amostragem constatou-se mudanças na diversidade funcional dos peixes da planície de inundação entre diferentes ambientes, lagoas e rios. Os resultados responderam as hipóteses de que: 1. Eventos de El Niño intensifiquem cheias na PIARP e, consequentemente, provoquem uma homogeneização funcional da assembleia de peixes; 2. Diferentes guildas funcionais serão favorecidas em épocas de El Niño ou La Niña. Obteve-se a mensuração de ENSO pelo índice de ONI (Oceanic Niño Index), enquanto que o nível hidrométrico do alto rio Paraná foi obtido pela medição diária em uma régua hidrométrica. Os peixes foram coletados com redes de espera em diferentes ambientes da planície de inundação, lagoas e rios, sendo agrupados em guildas reprodutivas e alimentares, usados para calcular índices de diversidade funcional. Testou-se como o ONI afeta o nível hidrométrico do alto rio Paraná (correlação de Pearson); como o ENSO afeta a composição funcional dos peixes da planície de inundação (PCoA; PERMANOVA), bem como o efeito da homogeneização; quais guildas funcionais são favorecidas em eventos de El Niño ou La Niña e se há efeito aditivo de ONI e nível hidrométrico sobre a composição funcional dos peixes da planície. O nível hidrométrico apresentou correlação positiva com ONI, indicando que eventos de El Niño causam cheias no alto rio Paraná, enquanto La Niña, seca. O efeito da homogeneização funcional de El Niño sobre os peixes foi mais visível em lagoas, sendo que os rios foram menos afetados por ENSO, e as cheias não foram intensas o suficiente para homogeneizarem esses dois tipos de ambiente, podendo ser o mesmo para demais planícies de inundação onde ENSO age da mesma maneira. Peixes com cuidado parental e invertívoros foram favorecidos em épocas de El Niño, enquanto que, peixes herbívoros e piscívoros foram favorecidos em épocas de La Niña. Os peixes migradores aparentam responder um ano após esses eventos climáticos, por possuírem ciclo de vida longo. O efeito aditivo de ONI e nível hidrométrico sobre a composição funcional não foi encontrado, sendo que outros fatores regionais e locais podem influenciar nessa interação. Entretanto, mesmo com esses fatores a assembleia de peixes da planície de inundação ainda responde à essas oscilações climáticas, sendo mais homogênea em eventos de El Niño do que em eventos de La Niña.
    Description: Masters
    Keywords: Peixes de água doce, Assembleia de ; El Niño Oscilação Sul (ENSO) ; Diversidade e índices funcionais ; Mudanças climáticas ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::A::Assemblages ; ASFA_2015::D::Diversity index ; ASFA_2015::I::Impacts ; ASFA_2015::C::Climatic changes ; ASFA_2015::E::El Nino phenomena
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 49pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 97
    facet.materialart.
    Unknown
    Efeitos do El Niño Southern Oscillation (ENSO) nas assembleias de peixes de uma planície de inundação Neotropical. (2020)
    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais.
    Details
    Publication Date: 2022-07-04
    Description: We evaluated the effects of El Niño Southern Oscillation in the fish assemblages of the upper Paraná River floodplain. Specifically, we tested if: (i) reservoirs regulate ENSO effects on the hydrometric level in the rivers that compose the plain (Rio Paraná – intensely dammed and Rio Ivinhema – not dammed); (ii) ENSO events influence the structure of the fish assemblages of the study rivers; and that (iii) the hydrometric level and the ENSO events will act synergistically on the structure of the fish assemblage of the Rio Paraná and Rio Ivinhema. ENSO data was gathered at the National Oceanic and Atmospheric Administration (NOAA), using as proxy the “Oceanic Niño Index” (ONI). Water level data were gathered from the hydrological stations located in the sampled area. Fish samplings were carried out quarterly between the years 2000 and 2018. In general, ENSO events were correlated with the hydrometric level of the Rio Paraná and Rio Ivinhema, but with lower correlation for the Rio Paraná, probably due to the effects of dams upstream the plain. The fish assemblages of the Rio Paraná and Rio Ivinhema presented distinct structures, and the ENSO events appeared to influence this differentiation. Migratory species were negatively correlated with ONI, but the greatest abundances were found one year after the events of El Niño ("Lag" of one year). Higher values of the attributes of the fish assemblages were recorded for the Rio Ivinhema, in all events of ENSO (La Niña, Neutral and El Niño), probably because it presents more pristine conditions. The hydrometric level and the ENSO events act synergistically, but distinctively in the study rivers, which should be related to their degree of impacts. Thus, the influence of ENSO in the studied area is apparently minimized, especially in the Rio Paraná, due to the flow control imposed by dams located upstream of the area.
    Description: Avaliou-se os efeitos do El Niño Oscilação Sul (El Niño Southern Oscillation-ENSO) nas assembleias de peixes da planície de inundação do alto rio Paraná. Especificamente, foram testados: (i) os reservatórios minimizam os efeitos do ENSO no nível hidrométrico nos rios que compõem a planície (rios Paraná - intensamente represado e Ivinhema - não represado); (ii) os eventos ENSO influenciam a estrutura das assembleias de peixes dos rios estudados; (iii) o nível hidrométrico e os eventos ENSO atuam sinergicamente na estrutura da assembleia de peixes dos rios Paraná e Ivinhema. Coletaram-se os dados do ENSO no National Oceanic and Atmospheric Administration (NOAA), utilizando como proxy o "Índice Niño Oceânico" (Oceanic Niño Index-ONI). Os dados do nível hidrométrico foram coletados nas estações fluviométricas localizadas na área de estudo. As amostragens de peixes transcorreram trimestralmente entre os anos 2000 e 2018. Em geral, os eventos ENSO correlacionaram-se com o nível hidrométrico dos rios Paraná e Ivinhema, mas com menor correlação para o rio Paraná, provavelmente devido aos efeitos de barragens a montante da planície. As assembleias de peixes dos respectivos rios apresentaram estruturas distintas, e os eventos ENSO pareciam influenciar essa diferenciação. As espécies migradoras possuem correlação negativa com o ONI, mas com registro de maiores abundâncias um ano após os eventos de El Niño ("Lag" de um ano). Maiores valores de riqueza e abundancia total de espécies registradas para o rio Ivinhema, em todos os eventos do ENSO (La Niña, Neutro e El Niño), provavelmente por apresentar condições mais pristinas. O nível hidrométrico e os eventos do ENSO atuam sinergicamente, mas de maneira distinta nos rios estudados, o que deve estar relacionado ao grau de impacto antrópico. Assim, a influência do ENSO na área de estudo é aparentemente minimizada, principalmente no rio Paraná, devido ao controle de vazão imposto por barragens localizadas a montante da área.
    Description: Masters
    Keywords: Peixes de água doce, Assembleia de ; El Niño Southern Oscillation (ENSO) ; Diversidade taxonômica ; Mudanças climáticas ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::A::Assemblages ; ASFA_2015::E::El Nino phenomena ; ASFA_2015::C::Climatic changes ; ASFA_2015::T::Taxonomy
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 41pp.
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 98
    facet.materialart.
    Unknown
    The emperor penguin - vulnerable to projected rates of warming and sea ice loss (2020)
    Elsevier
    Details
    Publication Date: 2022-05-26
    Description: © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Trathan, P. N., Wienecke, B., Barbraud, C., Jenouvrier, S., Kooyman, G., Le Bohec, C., Ainley, D. G., Ancel, A., Zitterbart, D. P., Chown, S. L., LaRue, M., Cristofari, R., Younger, J., Clucas, G., Bost, C., Brown, J. A., Gillett, H. J., & Fretwell, P. T. The emperor penguin - vulnerable to projected rates of warming and sea ice loss. Biological Conservation, 241, (2020): 108216, doi:10.1016/j.biocon.2019.108216.
    Description: We argue the need to improve climate change forecasting for ecology, and importantly, how to relate long-term projections to conservation. As an example, we discuss the need for effective management of one species, the emperor penguin, Aptenodytes forsteri. This species is unique amongst birds in that its breeding habit is critically dependent upon seasonal fast ice. Here, we review its vulnerability to ongoing and projected climate change, given that sea ice is susceptible to changes in winds and temperatures. We consider published projections of future emperor penguin population status in response to changing environments. Furthermore, we evaluate the current IUCN Red List status for the species, and recommend that its status be changed to Vulnerable, based on different modelling projections of population decrease of ≥50% over the current century, and the specific traits of the species. We conclude that current conservation measures are inadequate to protect the species under future projected scenarios. Only a reduction in anthropogenic greenhouse gas emissions will reduce threats to the emperor penguin from altered wind regimes, rising temperatures and melting sea ice; until such time, other conservation actions are necessary, including increased spatial protection at breeding sites and foraging locations. The designation of large-scale marine spatial protection across its range would benefit the species, particularly in areas that have a high probability of becoming future climate change refugia. We also recommend that the emperor penguin is listed by the Antarctic Treaty as an Antarctic Specially Protected Species, with development of a species Action Plan.
    Description: We thank Thomas J. Bracegirdle, Tony Phillips and Kevin Hughes for helpful comments on earlier drafts of this manuscript. PNT acknowledges the support of WWF-UK under GB095701 and SJ the support of NSF OPP1744794 and 1643901.
    Keywords: Antarctic ; Climate change ; Aptenodytes forsteri ; IUCN Red List threat status ; Protection ; Conservation
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 99
    facet.materialart.
    Unknown
    Intergyre salt transport in the climate warming response (2020)
    American Meteorological Society
    Details
    Publication Date: 2022-05-26
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 50(1), (2020): 255-268, doi:10.1175/JPO-D-19-0166.1.
    Description: Regional connectivity is important to the global climate salinity response, particularly because salinity anomalies do not have a damping feedback with atmospheric freshwater fluxes and may therefore be advected over long distances by ocean circulation, resulting in nonlocal influences. Climate model intercomparison experiments such as CMIP5 exhibit large uncertainty in some aspects of the salinity response, hypothesized here to be a result of ocean dynamics. We use two types of Lagrangian particle tracking experiments to investigate pathways of exchange for salinity anomalies. The first uses forward trajectories to estimate average transport time scales between water cycle regimes. The second uses reverse trajectories and a freshwater accumulation method to quantitatively identify remote influences in the salinity response. Additionally, we compare velocity fields with both resolved and parameterized eddies to understand the impact of eddy stirring on intergyre exchange. These experiments show that surface anomalies are readily exchanged within the ocean gyres by the mean circulation, but intergyre exchange is slower and largely eddy driven. These dynamics are used to analyze the North Atlantic salinity response to climate warming and water cycle intensification, where the system is broadly forced with fresh surface anomalies in the subpolar gyre and salty surface anomalies in the subtropical gyres. Under these competing forcings, strong intergyre eddy fluxes carry anomalously salty subtropical water into the subpolar gyre which balances out much of the local freshwater input.
    Description: We acknowledge the World Climate Research Programme’s Working Group on Coupled Modelling, which is responsible for CMIP, and we thank the climate modeling groups (listed in Table 1 of this paper) for producing and making available their model output. We also thank the creators of the SODA and ECCO reanalysis products. This work was supported by NASA Headquarters under the NASA Earth and Space Science Fellowship Program Award 80NSSC17K0372, and by National Science Foundation Award OCE-1433132. The SODA outputs used here can be accessed at http://www.atmos.umd.edu/~ocean/, and the ECCO outputs at https://ecco.jpl.nasa.gov/. Data from the CMIP5 ensemble is available at https://esgf-node.llnl.gov/projects/esgf-llnl/. The particle tracking code used for these experiments can be found at https://github.com/slevang/particle-tracking.
    Description: 2020-07-20
    Keywords: North Atlantic Ocean ; Eddies ; Hydrologic cycle ; Lagrangian circulation/transport ; Transport ; Climate change
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
  • 100
    facet.materialart.
    Unknown
    An observational estimate of the direct response of the cold-season atmospheric circulation to the Arctic Sea ice loss (2020)
    American Meteorological Society
    Details
    Publication Date: 2022-05-26
    Description: Author Posting. © American Meteorological Society, 2020. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Climate 33(9), (2020): 3863-3882, doi:10.1175/JCLI-D-19-0687.1.
    Description: The direct response of the cold-season atmospheric circulation to the Arctic sea ice loss is estimated from observed sea ice concentration (SIC) and an atmospheric reanalysis, assuming that the atmospheric response to the long-term sea ice loss is the same as that to interannual pan-Arctic SIC fluctuations with identical spatial patterns. No large-scale relationship with previous interannual SIC fluctuations is found in October and November, but a negative North Atlantic Oscillation (NAO)/Arctic Oscillation follows the pan-Arctic SIC fluctuations from December to March. The signal is field significant in the stratosphere in December, and in the troposphere and tropopause thereafter. However, multiple regressions indicate that the stratospheric December signal is largely due to concomitant Siberian snow-cover anomalies. On the other hand, the tropospheric January–March NAO signals can be unambiguously attributed to SIC variability, with an Iceland high approaching 45 m at 500 hPa, a 2°C surface air warming in northeastern Canada, and a modulation of blocking activity in the North Atlantic sector. In March, a 1°C northern Europe cooling is also attributed to SIC. An SIC impact on the warm Arctic–cold Eurasia pattern is only found in February in relation to January SIC. Extrapolating the most robust results suggests that, in the absence of other forcings, the SIC loss between 1979 and 2016 would have induced a 2°–3°C decade−1 winter warming in northeastern North America and a 40–60 m decade−1 increase in the height of the Iceland high, if linearity and perpetual winter conditions could be assumed.
    Description: This research was supported by the Blue-Action project (European Union’s Horizon 2020 research and innovation program, Grant 727852) and by the National Science Foundation (OPP 1736738).
    Description: 2020-10-06
    Keywords: Atmosphere-ocean interaction ; Climate change ; Climate variability ; Ice loss/growth
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER (OA)
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...