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  • 1
    Publication Date: 2024-04-27
    Description: Peatlands store and emit large amounts of greenhouse gases. With the climate changing due to global warming, measuring these emissions helps to get a better understanding of the role of peatlands in the global carbon cycle. Measurements at a bog site of the Siikaneva peatland show that the emissions vary along the different microtopographies shaped by their vegetation and ground water level. To upscale these measurements, a supervised classification of the study area was implemented in this study by testing a method that uses high-resolution multispectral aerial imagery, captured by a UAV (Uncrewed Aerial Vehicle), and a Random Forest classifier. A cohesive orthomosaic of the study area was produced, training data were generated to adjust the Random Forest model, and the study area was classified. The results show that the applied methods were successful in generating a multispectral orthomosaic as well as a classified raster of the study area. A mean classification accuracy of 75.7 % was achieved, which can be considered as a good result. Misclassification rates of neighboring microtopographies with similar vegetation could be mitigated by utilizing a LiDAR (Light Detection and Ranging) sensor in further studies.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Thesis , notRev
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  • 2
    Publication Date: 2024-04-26
    Description: Comprehensive metadata are key to making data FAIR. It is therefore essential to collect metadata in an organized and standardized way. For standardized data acquisition, ie. on research vessels, tools are already available and constantly improved. In land-based permafrost expeditions, however, the data and metadata are as diverse as the science questions behind them. We present an overview of this diversity in (meta)data and (meta)data collection and propose strategies to writing good and comprehensive metadata. We encourage to think about metadata right from the start and work on them steadily during the whole process from field work preparation to data collection and from data analysis to final publication. Easy to adapt templates and only choosing the tools that fit the specific data set increases the participation of the whole team.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , NonPeerReviewed
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  • 3
    Publication Date: 2024-04-26
    Description: Albedo – the reflectivity of a surface - is an important component in the energy budget, impacting the local to global climate. Data from nadir-viewing satellites can be combined with bidirectional reflectance distribution function (BRDF) data from multi-angular observation platforms to achieve realistic albedo values that acknowledge anisotropy. In my thesis, I evaluated how the land surface albedo varied on spatial and temporal scales during the snow-free period on Disko Island, Greenland. I examined how the albedo differed among the vegetation classes. Concerning the methodology, I assessed how the combination of MODIS BRDF data with Landsat 8 (L8) or Sentinel-2 (S2) influenced the albedo. The study area was located at the southern tip of Disko Island (69.27 °N, -53.47 °E) in West Greenland and covered a wetland and a range of tundra vegetation. I analysed automatic weather station (AWS) data from 2013 to 2022 and conducted mobile albedo measurements in August and September 2022 to examine the temporal and spatial variability. For the period from June to September 2022, I derived the L8 and S2 based albedo with inclusion of MODIS BRDF and narrow to broadband conversion and analysed their variability with regard to vegetation classes. In the snow-free period, the albedo increased from a monthly mean of 0.16 in June to 0.19 in September in the AWS data. The mobile measurements ranged from 〈 0.10 above bare soil and water to 〉 0.23 above areas dominated by lichen, Salix glauca or Equisetum arvense. The satellite-based albedo revealed temporally variable, significant correlations to normalised difference vegetation and moisture indices that reached values 〉 0.5 in the fen and wet heath class on several days. The albedo of shrubs was not notably smaller than other vegetation types but partly 0.01-0.05 above them in both the mobile measurements and the satellite-derived albedo. This finding challenges the assumption that shrubification causes climate forcing in all circumstances. The albedo of L8 and S2 differed to each other and the local data (root-mean-square error 0.04-0.14). The BRDF correction increased the albedo by 0.01 on average compared to nadir reflectance. L8 was better in reproducing the expected temporal and spatial variability of albedo than S2, which displayed less variability. S2 seemed to be more sensitive to atmospheric effects of haze and clouds influencing albedo. Thus, L8 seemed more suitable to calculate albedo in the study area. Though there were some methodological limitations, this thesis highlights aspects that should be considered when analysing albedo or jointly using L8 and S2 in high latitude regions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Thesis , notRev
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  • 4
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    Institute of Geography, Russian Academy of Sciences
    In:  EPIC3Geographical series, Institute of Geography, Russian Academy of Sciences, (4), pp. 69-69, ISSN: 0373-2444
    Publication Date: 2024-04-26
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
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  • 5
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    Copernicus Publications
    In:  EPIC3Climate of the Past, Copernicus Publications, 8(6), pp. 1897-1911, ISSN: 1814-9324
    Publication Date: 2024-04-26
    Description: The combination of permafrost history and dynamics, lake level changesRussian Arctic. The purpose of this study is to propose a depositional framework based on analyses of the core strata from the lake margin and historical reconstructions from various studies at the site. A sedimentological program has been conducted using frozen core samples from the 141.5m long El’gygytgyn 5011-3 permafrost well. The drill site is located in sedimentary permafrost west of the lake that partly fills the El’gygytgyn Crater. The total core sequence is interpreted as strata building up a progradational alluvial fan delta. Four macroscopically distinct sedimentary units are identified. Unit 1 (141.5–117.0 m) is comprised of ice-cemented, matrix-supported sandy gravel and intercalated sandy layers. Sandy layers represent sediments which rained out as particles in the deeper part of the water column under highly energetic conditions. Unit 2 (117.0–24.25 m) is dominated by ice-cemented, matrix-supported sandy gravel with individual gravel layers. Most of the Unit 2 diamicton is understood to result from alluvial wash and subsequent gravitational sliding of coarse-grained (sandy gravel) material on the basin slope. Unit 3 (24.25–8.5 m) has icecemented, matrix-supported sandy gravel that is interrupted by sand beds. These sandy beds are associated with flooding events and represent near-shore sandy shoals. Unit 4 (8.5–0.0 m) is ice-cemented, matrix-supported sandy gravel with varying ice content, mostly higher than below. It consists of slope material and creek fill deposits. The uppermost metre is the active layer (i.e. the top layer of soil with seasonal freeze and thaw) into which modern soil organic matter has been incorporated. The nature of the progradational sediment transport taking place from the western and northern crater margins may be related to the complementary occurrence of frequent turbiditic layers in the central lake basin, as is known from the lake sediment record. Slope processes such as gravitational sliding and sheet flooding occur especially during spring melt and promote mass wasting into the basin. Tectonics are inferred to have initiated the fan accumulation in the first place and possibly the off-centre displacement of the crater lake.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 6
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    In:  EPIC3Journal of Advances in Modelling Earth Systems, ISSN: 1942-2466
    Publication Date: 2024-04-26
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 7
    Publication Date: 2024-04-26
    Description: The cladoceran assemblages of the lacustrine deposits of the Krest-Yuryakh sequence (Marine Isotope Stage 5e, MIS5e; Last Interglacial, LIG) exposed at the southern coast of Bol’shoy Lyakhovsky Island and the Oyogos Yar mainland coast along the Dmitry Laptev Strait (Yakutia, Siberia, Russia) were investigated. Field studies on both sides of the Laptev Strait were conducted in 2002, 2007, and 2014. The vegetation of the study area is currently represented by Arctic tundra. The mean air temperature of the warmest month of the year (MTWA) is 3.5 °C for the studied sites on Bol’shoy Lyakhovsky Island and 6.9 °C for Oyogos Yar (https://www.worldclim.org; Fick and Hijmans, 2017). Age information of the Krest-Yuryakh lacustrine deposits is based on infrared-stimulated luminescence (IRSL) (Schirrmeister et al., submitted). Cladocera were studied in profile L7-11 on Bol’shoy Lyakhovsky Island and in profiles Oya-3-11, Oy7-01, Oy7-08, Oya 5-1 on Oyogos Yar.? The studied fossil cladocera remains of Krest-Yuryakh deposits are exceptionally well preserved. The overall cladocera record comprises 13 taxa. The most common species are Chydorus cf. sphaericus, Bosmina sp. and Daphnia pulex gr. The cladoceran assemblages are dominated by littoral shallow-water taxa, such as Chydorus cf. sphaericus, Alona guttata / Coronatella rectangula. However, profile L7-11 on Bol’shoy Lyakhovsky had very low concentrations of specimens of which Chydorus cf. sphaericus is the most common species. The cladoceran records on Oyogos Yar are more diverse and had much higher concentrations than those on Bol’shoy Lyakhovsky. Most of the cladoceran remains on Oyogos Yar belong to littoral phytophilous species, associated with macrophytes. In the cladoceran communities of Oyogos Yar, along with cold-water taxa, also more thermophilic taxa were found. In particular, the findings of remains of the species L. leidigi indicate much warmer conditions in the past than today. According to Flößner (2000), this species is absent nowadays in the arctic-subarctic zones, but present in the boreal zone. Thus, the modern distribution of L. leidigi is located considerably further south today. The northernmost known discovery of this species in Yakutia (northern Russia) is located in the basin of the Omoloy River (MTWA of +11.5 °C, Frolova & Nigmatullin, unpublished data).We conclude that the climatic conditions were more favorable for cladocerans on Oyogos Yar than on Bol’shoy Lyakhovsky in the Last Interglacial (LIG) sub-stage. The cladoceran assemblages of Oyogos Yar indicate lacustrine habitats with a well-developed vegetated littoral zone as well pelagic open-water zones in the paleo-lakes. Discoveries of cladoceran taxa significantly north of their modern ranges allow the reconstruction of warmer climatic conditions during LIG. Presumably, on Oyogos Yar, the mean temperature of the warmest month (MTWA) was at least ~4.5°C higher than today, which is supported by independent proxy-based - temperature reconstructions such as plant macro-fossils, pollen, and chironomids (Kienast et al., 2011) as well as by climate modeling simulations (Schirrmeister et al., submitted).
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , NonPeerReviewed
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  • 8
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    Public Library of Science (PLoS)
    In:  EPIC3PLOS ONE, Public Library of Science (PLoS), 19(4), pp. e0300138-e0300138, ISSN: 1932-6203
    Publication Date: 2024-04-26
    Description: Using the climate model CLIMBER-X, we present an efficient method for assimilating the temporal evolution of surface temperatures for the last deglaciation covering the period 22000 to 6500 years before the present. The data assimilation methodology combines the data and the underlying dynamical principles governing the climate system to provide a state estimate of the system, which is better than that which could be obtained using just the data or the model alone. In applying an ensemble Kalman filter approach, we make use of the advances in the parallel data assimilation framework (PDAF), which provides parallel data assimilation functionality with a relatively small increase in computation time. We find that the data assimilation solution depends strongly on the background evolution of the decaying ice sheets rather than the assimilated temperatures. Two different ice sheet reconstructions result in a different deglacial meltwater history, affecting the large-scale ocean circulation and, consequently, the surface temperature. We find that the influence of data assimilation is more pronounced on regional scales than on the global mean. In particular, data assimilation has a stronger effect during millennial warming and cooling phases, such as the Bølling-Allerød and Younger Dryas, especially at high latitudes with heterogeneous temperature patterns. Our approach is a step toward a comprehensive paleo-reanalysis on multi-millennial time scales, including incorporating available paleoclimate data and accounting for their uncertainties in representing regional climates.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
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  • 9
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    Universidade Estadual de Maringá. Departamento de Biologia. Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais
    Publication Date: 2024-04-26
    Description: The freshwater ichthyofauna is largely threatened by the anthropogenic impacts in these ecosystems. The climatic changes caused by human actions and dams’ constructions concerningly affects the freshwater fishes, including its biotic interactions network. Thus, this work aimed at evaluating the Upper Paraná River floodplain’s (UPRF) ichthyofauna under the impacts caused by climate changes, years of extreme drought an extreme flood, and under the impacts caused by the construction of an upstream dam, the Sérgio Motta Hydroelectric Power Plant, Brazil. The sampled years were classified in extreme drought, neutral and extreme flood, according to the predominant characteristics of its hydrological regime, and in pré-damming years, before the upstream hydroelectric power plant construction and reservoir’s flooding, and post-damming years. The abiotic and hydrometric variables were concurrently sampled with the abundance of fish species, allowing to exclude the environmental variables’ effects over the species’ cooccurrence, using multivariate generalized linear models with latent variables. The force of the interspecific biotic interactions was obtained through cooccurrence values for each pair of species, visualized through negative, neutral, and positive values. Regarding the results involving the hydrological regime influence, it was observed differences between drought, neutral and flood years, with stronger cooccurrence values between the UPRF’s ichthyofauna in drought years (for positive and negative values). Regarding the results involving the construction of the UPRF’s upstream dam, it was observed differences comparing the pré-damming and post-damming years cooccurrence patters, with predominantly positive values in post-damming years, and predominantly neutral cooccurrences in pré-damming years. These work results indicate the increment of the cooccurrence values between a floodplain’s fish species due to extreme droughts and upstream dams’ constructions, once the cooccurrence values were more intense under these conditions. Stands out the importance of biotic interactions for the elaboration of management plans and freshwater species conservation in response to anthropogenic actions.
    Description: A ictiofauna de ambientes de água doce se encontra amplamente ameaçada por ações antrópicas. As mudanças climáticas e a construção de barragens afetam os peixes de água doce e suas redes de interações bióticas. Neste contexto, este estudo avaliou a ictiofauna da planície de inundação do alto rio Paraná (PIARP) sob os impactos de mudanças climáticas, épocas de secas e cheias extremas, e sob os impactos causados pela construção de uma barragem a montante, a Usina Hidrelétrica Sérgio Motta, Brasil. Os anos amostrados foram classificados em anos de seca extrema, neutros e de cheia extrema, de acordo com as condições predominantes de seu regime hidrológico, e em anos de pré-barramento, antes da construção e inundação do reservatório da usina hidrelétrica a montante, e pós-barramento. As variáveis abióticas e variáveis hidrométricas foram amostradas concomitantemente com a abundância das espécies de peixe, permitindo excluir o efeito das variáveis ambientais sobre a ocorrência das espécies, com o uso de modelos lineares generalizados multivariados de variáveis latentes. Obteve-se a força das interações bióticas interespecíficas pelos valores de coocorrência, positivos ou negativos, entre cada par de espécies. Com relação aos resultados envolvendo a influência dos regimes hidrológicos, foram encontradas diferenças nos valores médios de coocorrência entre anos de seca extrema, anos neutros e anos de cheia extrema, indicando que os valores de coocorrência são mais fortes entre a ictiofauna da PIARP (tanto interações positivas quanto negativas) em anos de seca. Para os efeitos da construção da barragem a montante da PIARP, observou-se diferenças entre os padrões de coocorrência de espécies antes e após a sua construção, indicando valores de coocorrência predominantemente positivos no período pós-barramento, e coocorrências predominantemente neutras no período pré-barramento. Os resultados indicam incremento nos padrões de coocorrência entre as espécies de peixes da planície de inundação frente secas extremas e construção de barragens a montante, uma vez que os valores de coocorrência foram mais intensos sob essas condições. Destaca-se a importância das interações bióticas em resposta às ações antrópicas para a elaboração de planos de manejo e para a conservação das espécies de peixes de água doce.
    Description: PhD
    Keywords: Peixes de água doce ; Comunidades, Ecologia de ; Interações bióticas ; Ações antrópicas ; Coocorrência de espécies ; Variáveis ambientais ; Variáveis hidrométricas ; Generalized linear latent variable models (GLLVM) ; ASFA_2015::F::Freshwater ecology ; ASFA_2015::F::Freshwater fish ; ASFA_2015::C::Communities (ecological) ; ASFA_2015::I::Interactions ; ASFA_2015::A::Anthropogenic factors ; ASFA_2015::S::Species diversity ; ASFA_2015::E::Environmental factors ; ASFA_2015::H::Hydrometers
    Repository Name: AquaDocs
    Type: Thesis/Dissertation
    Format: 71pp.
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  • 10
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    Comisión Colombiana del Océano | Bogotá D.C., Colombia
    Publication Date: 2024-04-26
    Description: Hace tres años atrás el Comité Técnico Nacional de Coordinación de Datos e Información Oceánicos (CTN Diocean) de la Comisión Colombiana del Océano (CCO), estableció un plan de trabajo que abarca cinco años de actividades institucionales para fortalecer la gestión de estos importantes activos del país. Para entonces se tuvieron en cuenta diferentes estrategias como línea base para definir las tareas a desarrollar, y en la actualidad es gratificante para miembros e invitados permanentes confirmar, que lo planeado sigue vigente y acorde con los desafíos del ‘Decenio de las Ciencias Oceánicas para el Desarrollo Sostenible’, las necesidades de la comunidad y los recientes lineamientos de política nacionales e internacionales. En el presente número del Boletín CTN Diocean, se destacan entre otros, dos reconocimientos logrados en el nivel internacional por parte de instituciones que hacen parte del comité y que le aportan al fortalecimiento de la gestión de datos oceánicos de Colombia: el primero, los datos abiertos oceanográficos como una actividad del ‘Decenio de las Ciencias Oceánicas para el Desarrollo Sostenible’ de la Comisión Oceanográfica Intergubernamental (COI); y el segundo, la copresidencia para el periodo entre sesiones 2023-2025 del programa para el Intercambio Internacional de Datos Oceanográficos (COI-IODE) junto con Suecia, en el marco de la cual se inició la asesoría con nuestros hermanos panameños en la materia.
    Description: Published
    Description: Not Known
    Keywords: Acceso abierto ; Usuario de información ; Gestión de la información ; Base de datos ; Sistema de información ; Organización y gestión ; ASFA_2015::G::Geographic information systems ; ASFA_2015::I::Information centres ; ASFA_2015::D::Databases ; ASFA_2015::I::Information handling
    Repository Name: AquaDocs
    Type: Book/Monograph/Conference Proceedings
    Format: 29
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  • 11
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    Universität Göttingen,Abteilung Bodenphysik
    In:  Universität Göttingen
    Publication Date: 2024-04-26
    Description: research
    Keywords: Wasserhaushalt ; Bodenphysik ; Physikochemische Bodeneigenschaft ; Hydrodynamik Hochebene ; Pseudogley ; Waldboden
    Language: German
    Type: doc-type:book
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  • 12
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    Universität Göttingen,Abteilung Bodenphysik
    In:  Universität Göttingen
    Publication Date: 2024-04-26
    Description: research
    Keywords: Pflanzensoziologie ; Waldgesellschaft ; Ostalpen ; Exkursion Italien ; Waldpflanzen ; Forst Ostalpen ; Vegetation ; Italienische Alpen ; Oberitalien
    Language: German
    Type: doc-type:book
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  • 13
    Publication Date: 2024-04-26
    Description: The Amazonian rainforest is arguably the most species-rich terrestrial ecosystem in the world, yet the timing of the origin and volutionary causes of this diversity are a matter of debate. We review the geologic and phylogenetic evidence from Amazonia and compare it with uplift records from the Andes. This uplift and its effect on regional climate fundamentally changed the Amazonian landscape by reconfiguring drainage patterns and creating a vast influx of sediments into the basin. On this “Andean” substrate, a region-wide edaphic mosaic developed that became extremely rich in species, particularly in Western Amazonia. We show that Andean uplift was crucial for the evolution of Amazonian landscapes and ecosystems, and that current biodiversity patterns are rooted deep in the pre-Quaternary.
    Keywords: Amazonia ; evolution ; biodiversity
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
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  • 14
    Publication Date: 2024-04-26
    Description: Tropical coastal benthic communities will change in species composition and relative dominance due to global (e.g., increasing water temperature) and local (e.g., increasing terrestrial influence due to land-based activity) stressors. This study aimed to gain insight into possible trajectories of coastal benthic assemblages in Raja Ampat, Indonesia, by studying coral reefs at varying distances from human activities and marine lakes with high turbidity in three temperature categories (〈31 °C, 31–32 °C, and 〉32 °C). The benthic community diversity and relative coverage of major benthic groups were quantified via replicate photo transects. The composition of benthic assemblages varied significantly among the reef and marine lake habitats. The marine lakes 〈31 °C contained hard coral, crustose coralline algae (CCA), and turf algae with coverages similar to those found in the coral reefs (17.4–18.8% hard coral, 3.5–26.3% CCA, and 15–15.5% turf algae, respectively), while the higher temperature marine lakes (31–32 °C and 〉32 °C) did not harbor hard coral or CCA. Benthic composition in the reefs was significantly influenced by geographic distance among sites but not by human activity or depth. Benthic composition in the marine lakes appeared to be structured by temperature, salinity, and degree of connection to the adjacent sea. Our results suggest that beyond a certain temperature (〉31 °C), benthic communities shift away from coral dominance, but new outcomes of assemblages can be highly distinct, with a possible varied dominance of macroalgae, benthic cyanobacterial mats, or filter feeders such as bivalves and tubeworms. This study illustrates the possible use of marine lake model systems to gain insight into shifts in the benthic community structure of tropical coastal ecosystems if hard corals are no longer dominant.
    Keywords: Benthic cover ; Biodiversity ; Coral reef ; Marine lake ; Anthropogenic pressures ; Raja ; Ampat (Indonesia)
    Repository Name: National Museum of Natural History, Netherlands
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  • 15
    Publication Date: 2024-04-26
    Description: Dynamics of microbiomes through time are fundamental regarding survival and resilience of their hosts when facing environmental alterations. As for marine species with commercial applications, such as marine sponges, assessing the temporal change of prokaryotic communities allows us to better consider the adaptation of sponges to aquaculture designs. The present study aims to investigate the factors shaping the microbiome of the sponge Dactylospongia metachromia, in a context of aquaculture development in French Polynesia, Rangiroa, Tuamotu archipelago. A temporal approach targeting explants collected during farming trials revealed a relative high stability of the prokaryotic diversity, meanwhile a complementary biogeographical study confrmed a spatial specifcity amongst samples at diferent longitudinal scales. Results from this additional spatial analysis confrmed that diferences in prokaryotic communities might frst be explained by environmental changes (mainly temperature and salinity), while no signifcant efect of the host phylogeny was observed. The core community of D. metachromia is thus characterized by a high spatiotemporal constancy, which is a good prospect for the sustainable exploitation of this species towards drug development. Indeed, a microbiome stability across locations and throughout the farming process, as evidenced by our results, should go against a negative infuence of sponge translocation during in situ aquaculture.
    Keywords: Holobiont ; Marine sponges ; Microbiome ; Farming trials ; Biogeography ; French Polynesia
    Repository Name: National Museum of Natural History, Netherlands
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  • 16
    Publication Date: 2024-04-26
    Description: With the aim of dating the early salt production at Puntone di Scarlino (Central Tuscany, Italy) and establishing the environmental history of this coastal site, a sediment core was studied, taken from the lagoon next to the archaeological site. Diachronic radiocarbon dating of terrestrial plant macro remains and Loripes orbiculatus (Poli, 1795) shells, a burrowing lucinid bivalve occurring throughout the sediment cored, revealed a Marine Reservoir Effect (MRE) that varied markedly over time. Between ca. 4000 and 2500 cal BP, the △R values ranged between −50 and + 500 14C years, thus rendering the Loripes shells truly unsuited for independent radiocarbon dating. Extensive geochemical and palaeoecological study of the core and its environment showed that none of the ubiquitous explanations for this highly variable MRE, such as ‘hard water’ or ‘upwelling old seawater’, can be valid. We attribute the phenomenon to the uptake by this lucinid mollusc of ‘old carbon’ from the sediment column into which it had burrowed, released by diagenetic microbial decomposition processes such as methanogenesis. The age of this inorganic carbon varied, being linked to the sedimentation rate: with decreasing sedimentation rate its impact will increase, whereas at high sedimentation rates its impact will likely be minimal. Our results raise serious doubts about the suitability for radiocarbon dating of benthic fauna from shallow coastal environments and point at these diagenetic processes as potentially important sources of ‘old carbon’.
    Keywords: Holocene ; Paleoceanography ; Europe ; Radiogenic isotopes ; Marine reservoir effect ; Loripes orbiculatus ; Diagenetic carbon flux
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
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  • 17
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    Naturalis Biodiversity Center
    In:  Persoonia - Molecular Phylogeny and Evolution of Fungi vol. 45, pp. 221-249
    Publication Date: 2024-04-26
    Description: Specimens of Nectria spp. and Nectriella rufofusca were obtained from the fungarium of Pier Andrea Saccardo, and investigated via a morphological and molecular approach based on MiSeq technology. ITS1 and ITS2 sequences were successfully obtained from 24 specimens identified as ‘Nectria’ sensu Saccardo (including 20 types) and from the type specimen of Nectriella rufofusca. For Nectria ambigua, N. radians and N. tjibodensis only the ITS1 sequence was recovered. On the basis of morphological and molecular analyses new nomenclatural combinations for Nectria albofimbriata, N. ambigua, N. ambigua var. pallens, N. granuligera, N. peziza subsp. reyesiana, N. radians, N. squamuligera, N. tjibodensis and new synonymies for N. congesta, N. flageoletiana, N. phyllostachydis, N. sordescens and N. tjibodensis var. crebrior are proposed. Furthermore, the current classification is confirmed for Nectria coronata, N. cyanostoma, N. dolichospora, N. illudens, N. leucotricha, N. mantuana, N. raripila and Nectriella rufofusca. This is the first time that these more than 100-yr-old specimens are subjected to molecular analysis, thereby providing important new DNA sequence data authentic for these names.
    Keywords: Ecology ; Evolution ; Behavior and Systematics ; ancient DNA ; Ascomycota ; Hypocreales ; Illumina ; ribosomal sequences ; Sordariomycetes
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
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  • 18
    Publication Date: 2024-04-26
    Description: Novel species of fungi described in this study include those from various countries as follows: Australia, Austroboletus asper on soil, Cylindromonium alloxyli on leaves of Alloxylon pinnatum, Davidhawksworthia quintiniae on leaves of Quintinia sieberi, Exophiala prostantherae on leaves of Prostanthera sp., Lactifluus lactiglaucus on soil, Linteromyces quintiniae (incl. Linteromyces gen. nov.) on leaves of Quintinia sieberi, Lophotrichus medusoides from stem tissue of Citrus garrawayi, Mycena pulchra on soil, Neocalonectria tristaniopsidis (incl. Neocalonectria gen. nov.) and Xyladictyochaeta tristaniopsidis on leaves of Tristaniopsis collina, Parasarocladium tasmanniae on leaves of Tasmannia insipida, Phytophthora aquae-cooljarloo from pond water, Serendipita whamiae as endophyte from roots of Eriochilus cucullatus, Veloboletus limbatus (incl. Veloboletus gen. nov.) on soil. Austria, Cortinarius glaucoelotus on soil. Bulgaria, Suhomyces rilaensis from the gut of Bolitophagus interruptus found on a Polyporus sp. Canada, Cantharellus betularum among leaf litter of Betula, Penicillium saanichii from house dust. Chile, Circinella lampensis on soil, Exophiala embothrii from rhizosphere of Embothrium coccineum. China, Colletotrichum cycadis on leaves of Cycas revoluta. Croatia, Phialocephala melitaea on fallen branch of Pinus halepensis. Czech Republic, Geoglossum jirinae on soil, Pyrenochaetopsis rajhradensis from dead wood of Buxus sempervirens. Dominican Republic, Amanita domingensis on litter of deciduous wood, Melanoleuca dominicana on forest litter. France, Crinipellis nigrolamellata (Martinique) on leaves of Pisonia fragrans, Talaromyces pulveris from bore dust of Xestobium rufovillosum infesting floorboards. French Guiana, Hypoxylon hepaticolor on dead corticated branch. Great Britain, Inocybe ionolepis on soil. India, Cortinarius indopurpurascens among leaf litter of Quercus leucotrichophora. Iran, Pseudopyricularia javanii on infected leaves of Cyperus sp., Xenomonodictys iranica (incl. Xenomonodictys gen. nov.) on wood of Fagus orientalis. Italy, Penicillium vallebormidaense from compost. Namibia, Alternaria mirabibensis on plant litter, Curvularia moringae and Moringomyces phantasmae (incl. Moringomyces gen. nov.) on leaves and flowers of Moringa ovalifolia, Gobabebomyces vachelliae (incl. Gobabebomyces gen. nov.) on leaves of Vachellia erioloba, Preussia procaviae on dung of Procavia capensis. Pakistan, Russula shawarensis from soil on forest floor. Russia, Cyberlindnera dauci from Daucus carota. South Africa, Acremonium behniae on leaves of Behnia reticulata, Dothiora aloidendri and Hantamomyces aloidendri (incl. Hantamomyces gen. nov.) on leaves of Aloidendron dichotomum, Endoconidioma euphorbiae on leaves of Euphorbia mauritanica, Eucasphaeria proteae on leaves of Protea neriifolia, Exophiala mali from inner fruit tissue of Malus sp., Graminopassalora geissorhizae on leaves of Geissorhiza splendidissima, Neocamarosporium leipoldtiae on leaves of Leipoldtia schultzii, Neocladosporium osteospermi on leaf spots of Osteospermum moniliferum, Neometulocladosporiella seifertii on leaves of Combretum caffrum, Paramyrothecium pituitipietianum on stems of Grielum humifusum, Phytopythium paucipapillatum from roots of Vitis sp., Stemphylium carpobroti and Verrucocladosporium carpobroti on leaves of Carpobrotus quadrifolius, Suttonomyces cephalophylli on leaves of Cephalophyllum pilansii. Sweden, Coprinopsis rubra on cow dung, Elaphomyces nemoreus from deciduous woodlands. Spain, Polyscytalum pini-canariensis on needles of Pinus canariensis, Pseudosubramaniomyces septatus from stream sediment, Tuber lusitanicum on soil under Quercus suber. Thailand, Tolypocladium flavonigrum on Elaphomyces sp. USA, Chaetothyrina spondiadis on fruits of Spondias mombin, Gymnascella minnisii from bat guano, Juncomyces patwiniorum on culms of Juncus effusus, Moelleriella puertoricoensis on scale insect, Neodothiora populina (incl. Neodothiora gen. nov.) on stem cankers of Populus tremuloides, Pseudogymnoascus palmeri from cave sediment. Vietnam, Cyphellophora vietnamensis on leaf litter, Tylopilus subotsuensis on soil in montane evergreen broadleaf forest. Morphological and culture characteristics are supported by DNA barcodes.
    Keywords: Ecology ; Evolution ; Behavior and Systematics ; ITS nrDNA barcodes ; LSU ; new taxa ; systematics
    Repository Name: National Museum of Natural History, Netherlands
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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  • 21
    Publication Date: 2024-04-26
    Description: The oxidation of hydrocarbons, including methane, is part of interrelated hydrogeochemical reactions affecting the carbon budget in Earth’s crust. To investigate these processes in deep siliciclastic strata, we analyzed core samples from Lower Triassic red beds in the Mahu Sag (Junggar Basin, northwest China) by coupling petrological observations with high-resolution in situ secondary ion mass spectroscopy stable carbon and oxygen isotope analyses and clumped isotopes (Δ47) of authigenic calcite. The strata contain variable oil and gas content as well as abundant high-valence Fe and/or Mn oxides. Three sequential generations of cement occur, which are characterized as (1) non-luminescent, early diagenetic calcite (MnO 〈0.3%, δ13CVPDB [Vienna Peedee belemnite] = −5.6‰ to −4.1‰); (2) bright-orange luminescent late-stage I calcite (0.75%−5.23% MnO, δ13C = −51.4‰ to −25.8‰); and (3) dull-orange late-stage II calcite (4.10%−12.93% MnO, δ13C = −91.4‰ to −30.9‰). Clumped isotopic thermometry reveals that the calcite precipitation temperature increases successively from 〈40 °C, to 81−107 °C, to finally 107−132 °C, corresponding to three precipitation time periods: before the Late Triassic, from the Early Jurassic to the Early Cretaceous, and from the Early Cretaceous to the present, respectively. δ13C values of −55.7‰ to −25.8‰ indicate that late-stage I calcite is the final product of oxidation of both methane and C2+ hydrocarbons, whereas δ13C values as low as −91‰ indicate that late-stage II calcite is mainly derived from the thermochemical oxidation of methane (δ13C = −46.8‰ to −39.3‰) induced by high-valence Mn and/or Fe oxides. For late-stage I calcite, hydrocarbon oxidation was most likely promoted by high temperatures, although microbial oxidation cannot be completely ruled out. The higher precipitation temperature of late-stage II calcite demonstrates that the oxidation of methane requires higher activation energies than oxidation of C2+ hydrocarbons. We provide reliable geochemical evidence for thermally induced sequential oxidation of hydrocarbons within deep siliciclastic strata.
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  • 22
    Publication Date: 2024-04-26
    Description: Understanding the spatiotemporal dynamics of river water chemistry from its source to sinks is critical for constraining the origin, transformation, and “hotspots” of contaminants in a river basin. To provide new spatiotemporal constraints on river chemistry, dissolved trace element concentrations were measured at 17 targeted locations across the Ramganga River catchment. River water samples were collected across three seasons: pre-monsoon, monsoon, and post-monsoon between 2019 and 2021. To remove the dependency of trace element concentrations on discharge, we used molar ratios, as discharge data on Indian transboundary rivers are not publicly available. The dataset reveals significant spatiotemporal variability in dissolved trace element concentrations of the Ramganga River. Samples collected upstream of Moradabad, a major industrial city in western Uttar Pradesh, are characterized by ~ 1.2–2.5 times higher average concentrations of most of the trace elements except Sc, V, Cr, Rb, and Pb, likely due to intense water–rock interactions in the headwaters. Such kind of enrichment in trace metal concentrations was also observed at sites downstream of large cities and industrial centers. However, such enrichment was not enough to bring a major change in the River Ganga chemistry, as the signals got diluted downstream of the Ramganga-Ganga confluence. The average river water composition of the Ramganga River was comparable to worldwide river water composition, albeit a few sites were characterized by very high concentrations of dissolved trace elements. Finally, we provide an outlook that calls for an assessment of stable non-traditional isotopes that are ideally suited to track the origin and transformation of elements such as Li, Mg, Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Sr, Ag, Cd, Sn, Pt, and Hg in Indian rivers.
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    Publication Date: 2024-04-26
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  • 24
    Publication Date: 2024-04-26
    Description: The southwest monsoon rainfall not only provides water and food security over the Indo-Gangetic Basin, it also plays an important role in reducing atmospheric pollution by removing ambient particles via wet deposition processes. In addition to rainfall, aerosol loading and its removal from ambient air are also governed by other meteorological parameters, such as the temperature, humidity, wind speed, and wind direction. To understand the effect of southwest monsoon withdrawal on aerosol loading over the Indo-Gangetic Basin, airborne particles (PM10 size fraction) and meteorological parameters, including the temperature, humidity, rainfall, wind speed, and wind direction data were collected between July and October 2015 at Kanpur, India, which is a large industrial city in the central part of the Indo-Gangetic Basin. The study shows that withdrawal of the southwest monsoon since July 2015 increased the aerosol loading in the ambient air by up to 28, 43 and 152% during August, September, and October, respectively. The aerosol loading exceeded the ambient Indian National Air Quality Standard limit of 100 μg/m–3 just within 3 months. In addition to increased aerosol mass loading, the concentration of heavy metals (Cr, Ni, Cu, and Cd) in the aerosols also increased with monsoon withdrawal. The only heavy metal that did not show an increasing trend was Pb, which indicates that Pb is either coming from local source(s) or that Pb was not efficiently scavenged by wet deposition processes. In general, Cd, Pb, and Cu concentrations were 10–1500 times higher when compared to the upper continental crust and were mostly derived from coal-burning products. The study shows that southwest monsoon strongly influence the physiochemical properties of aerosols over the Indo-Gangetic Basin.
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  • 25
    Publication Date: 2024-04-26
    Description: latinum group element (PGE) is among the emerging airborne contaminants mainly emitting from automobile catalysts. The ambient PGE concentration in Asia is expected to rise due to an increase in vehicle sales over the last two decades. Of all the Asian countries, the automobile industry in India has grown at a spectacular rate (〉 50% in the last 10 years) and is expected to become a hotspot of global PGE contamination. However, the Indian subcontinent can be regarded as a “white spot” on the global PGE contamination map, indicating the presence of very limited field data. Here, we report the annual time-series record of PGE concentrations of the airborne particulate matter 〈10-micron-sized (PM10) collected from a high-altitude remote site in the central Himalaya that draws a significant fraction of air mass from the heavily polluted Indo-Gangetic Plain (IGP). The time-series record reveals that the PGE concentrations in PM10 are amongst the lowest recorded levels globally, lack seasonal variability, and are derived from aged catalyst and coal combustion products. We conclude that the annual average Pt, Pd, Rh, and Ru concentrations of 0.88 ± 0.57, 2.07 ± 1.75, 0.14 ± 0.1, and 0.16 ± 0.08 pg m−3, respectively, would serve as a baseline concentration in PM10 to judge the future magnitude of PGE contamination in the Indian subcontinent.
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  • 26
    Publication Date: 2024-04-26
    Description: he Indo-Gangetic Plain (IGP) is one of the most highly polluted regions of the world, yet the temporal pattern of transport of anthropogenic aerosols from this region to the Himalayas is poorly constrained. On the basis of the seasonal variation of planetary boundary layer heights, air mass back trajectory analysis, and year-long time-series data for 208Pb/204Pb, 207Pb/204Pb, 206Pb/204Pb, and 143Nd/144Nd from aerosols collected over a high-altitude station, we demonstrate that anthropogenic Pb transport to the glacierized catchment has a seasonal pattern. The Pb isotope data reveal that during winter, the thinned boundary layer traps up to 10 ± 7% more coal-derived Pb in the IGP. In contrast, in nonwinter months, a thicker boundary layer and enhanced subtropical westerly winds result in efficient Pb transport to the Himalayas. As Pb isotope ratios are robust conservative chemical tracers and Pb is predominantly derived from anthropogenic sources, these observations suggest that enhanced transport of anthropogenic aerosols to the glacierized catchment of the Himalayas coincides with higher near-surface temperatures in the summer, creating positive feedback that enhances melting. Our results further suggest that 〉50% of Pb in the Himalayan aerosols originates from the resuspension of historic Pb derived from phased out leaded gasoline, highlighting the importance of legacy Pb stored in the Indo-Gangetic Plains.
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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  • 31
    Publication Date: 2024-04-26
    Description: The Indo-Gangetic Basin (IGB) alluvial aquifer system provides a reliable drinking water supply to over half a billion people. Understanding the groundwater quality, aquifer processes, groundwater storage, and depletion trends in the IGB alluvial aquifer system— one of the world's most important freshwater resources has been the focus of many previous studies. However, understanding what governs uranium variability in the IGB alluvial aquifer system— for example, whether uranium is released from natural deposits or anthropogenic sources such as mill tailing, emissions from the nuclear industry, combustion of fossil fuels, and phosphate fertilizers— are under-explored but critically important for constraining the environmental fate of uranium. Here, we present surface and groundwater uranium concentration data in the central parts of the IGB alluvial aquifer system. We find a high concentration of groundwater uranium above the World Health Organization provisional guideline value of 30 μg/L in 17% (n = 29) of collected groundwater samples, whereas other heavy metals, namely Cr, Ni, Pb, and Cd were within the recommended range. Trace element systematic demonstrates that anomalous uranium enrichment is primarily derived from geogenic sources, while uranium mobility is predominantly controlled by the alkalinity (a proxy for bicarbonate), hence by soluble uranyl carbonate complexes. As in the year 2020, the Bureau of Indian Standard incorporated uranium as a possible drinking water contaminant, our dataset calls for additional assessments of groundwater uranium concentrations in Indian groundwater resources because uranium concentration data are scarce compared to other geogenic contaminants such as arsenic and fluoride. We conclude that uranium, like arsenic and fluoride, is also critical geogenic contaminant in the alluvial aquifers that needs to be better monitored as higher levels of uranium in drinking water have adverse health effects.
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
    Description: Himalayan glaciers are invariably covered by supra-glacial debris. Of these glaciers, the Chhota Shigri Glacier (CSG) in the western Himalaya has minimal debris cover (3.4%), yet has a comparable melt rate to other Himalayan glaciers. Utilizing osmium isotopic composition, and major and trace element geochemistry of cryoconite, a dark colored aggregate of mineral and organic materials on the surface of the ablation zone of the CSG, we show that the surface of CSG is essentially free of anthropogenically emitted particles, contrary to many previous findings. Given this and the overall lack of debris, we conclude that the high melt rate of CSG is primarily related to the increase of the Earth's near-surface temperature linked directly to global warming. Therefore, the future meltwater supply for glacial-fed rivers originating from Lahaul and Spiti region would be most vulnerable for 〉50 million population living downstream and requires immediate attention.
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    Publication Date: 2024-04-26
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  • 41
    Publication Date: 2024-04-26
    Description: Groundwater contamination throughout India is a global concern as it feeds more than a billion people. Of all the contaminants, fluoride (F) is one of the most widespread and well documented since its toxic nature pose serious threats to human health. In India, groundwater F concentrations have been extensively studied over the past decades. These studies have generally concluded that the groundwater F concentrations are typically higher than the drinking water standard for human health. Here, we present the occurrence, distribution, and sources of groundwater F in the Kanpur Nagar and Kanpur Dehat districts covering ~ 6000 km2 of the area in the central part of the Ganga Basin. The result revealed significant spatial variability in dissolved F concentration ranging between 0.2 and 5.2 mg/L (average 0.9 ± 0.7 mg/L, n = 172, 1 SD), which is beyond the drinking water guideline (0.5–1.5 mg/L) of the Indian Standards. We find that 31% of groundwater sampled have F content below the optimal requirement of 0.5–1.0 mg/L causing dental caries problems. The F levels only exceeded the safe drinking water limit of 1.5 mg/L in 8% of the groundwater sampled mostly in the urban regions. Fluoride distribution shows a closer resemblance with the spatial distribution pattern of electrical conductivity, and total dissolved solids demonstrate that F in the shallow alluvial aquifers is largely derived from geogenic sources. This is further confirmed by a strong positive correlation (r = 0.91, p 〈 0.05) observed between chloride-normalized concentration of F and the sum of geogenic elements (∑Li, Rb, Sr, Ba). We additionally performed health risk assessments, which revealed that children are most vulnerable to dental caries (commonly known as tooth decay) and dental fluorosis problems. As F concentrations show large spatial variability in the studied aquifer, we suggest that uniform application of a single de-fluoridation and fluoridation technology on an aquifer or sub-aquifer scale without a detailed well-designed groundwater F survey will have an adverse health impact on local residents as optimal level of F in drinking water may not be compromised.
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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    Publication Date: 2024-04-26
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  • 46
    Publication Date: 2024-04-26
    Description: Enhanced geothermal systems (EGS) require cost-effective monitoring of fracture networks. We validate the capability of using borehole distributed acoustic sensing (DAS) ambient noise for fracture monitoring using core photos and core logs. The EGS Collab project has conducted 10 m scale field experiments of hydraulic fracture stimulation using 50–60 m deep experimental wells at the Sanford Underground Research Facility (SURF) in Lead, South Dakota. The first EGS Collab testbed is located at 1616.67 m (4850 ft) depth at SURF and consists of one injection well, one production well, and six monitoring wells. All wells are drilled subhorizontally from an access tunnel called a drift. The project uses a single continuous fiber-optic cable installed sequentially in the six monitoring wells to record DAS data for monitoring hydraulic fracturing during stimulation. We analyze 60 s time records of the borehole DAS ambient noise data and compute the noise root-mean-square (rms) amplitude on each channel (points along the fiber cable) to obtain DAS ambient noise rms amplitude depth profiles along the monitoring wellbore. Our noise rms amplitude profiles indicate amplitude peaks at distinct depths. We compare the DAS noise rms amplitude profiles with borehole core photos and core logs and find that the DAS noise rms amplitude peaks correspond to the locations of fractures or lithologic changes indicated in the core photos or core logs. We then compute the hourly DAS noise rms amplitude profiles in two monitoring wells during three stimulation cycles in 72 h and find that the DAS noise rms amplitude profiles vary with time, indicating the fracture opening/growth or closing during the hydraulic stimulation. Our results demonstrate that borehole DAS passive ambient noise can be used to detect fractures and monitor fracturing processes in EGS reservoirs.
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  • 47
    Publication Date: 2024-04-26
    Description: In this paper, we anticipate geospatial population distributions to quantify the future number of people living in earthquake-prone and tsunami-prone areas of Lima and Callao, Peru. We capitalize upon existing gridded population time series data sets, which are provided on an open-source basis globally, and implement machine learning models tailored for time series analysis, i.e., based on long short-term memory (LSTM) networks, for prediction of future time steps. Specifically, we harvest WorldPop population data and teach LSTM and convolutional LSTM models equipped with both unidirectional and bidirectional learning mechanisms, which are derived from different feature sets, i.e., driving factors. To gain insights regarding the competitive performance of LSTM-based models in this application context, we also implement multilinear regression and random forest models for comparison. The results clearly underline the value of the LSTM-based models for forecasting gridded population data; the most accurate prediction obtained with an LSTM equipped with a bidirectional learning scheme features a root-mean-squared error of 3.63 people per 100 × 100 m grid cell while maintaining an excellent model fit (R2= 0.995). We deploy this model for anticipation of population along a 3-year interval until the year 2035. Especially in areas of high peak ground acceleration of 207–210 cm s−2, the population is anticipated to experience growth of almost 30 % over the forecasted time span, which simultaneously corresponds to 70 % of the predicted additional inhabitants of Lima. The population in the tsunami inundation area is anticipated to grow by 61 % until 2035, which is substantially more than the average growth of 35 % for the city. Uncovering those relations can help urban planners and policymakers to develop effective risk mitigation strategies.
    Language: English
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  • 48
    Publication Date: 2024-04-26
    Keywords: Ablation area; Accumulation area; Accumulation area ratio; DATE/TIME; Date/time end; Equilibrium line altitude; GLAC; Glaciers Austria; Mass balance, total; Mass balance in ablation area; Mass balance in accumulation area; Sampling/measurements on glacier; Sonnblickkees; Specific mass balance; Specific mass balance in the ablation area; Specific mass balance in the accumulation area; SSK; Stubacher Sonnblick, Hohe Tauern, Austria; Total area
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  • 49
    Publication Date: 2024-04-26
    Keywords: Ablation area; Accumulation area; Accumulation area ratio; DATE/TIME; Date/time end; Equilibrium line altitude; GLAC; Glaciers Austria; Mass balance, total; Mass balance in ablation area; Mass balance in accumulation area; Sampling/measurements on glacier; Sonnblickkees; Specific mass balance; Specific mass balance in the ablation area; Specific mass balance in the accumulation area; SSK; Stubacher Sonnblick, Hohe Tauern, Austria; Total area
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    Publication Date: 2024-04-26
    Keywords: Ablation area; Accumulation area; Accumulation area ratio; DATE/TIME; Date/time end; Equilibrium line altitude; GLAC; Glaciers Austria; Mass balance, total; Mass balance in ablation area; Mass balance in accumulation area; Sampling/measurements on glacier; Sonnblickkees; Specific mass balance; Specific mass balance in the ablation area; Specific mass balance in the accumulation area; SSK; Stubacher Sonnblick, Hohe Tauern, Austria; Total area
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