ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
Filter
  • Wiley  (26,053)
  • Nature Publishing Group  (8,075)
  • 2020-2024  (166)
  • 1995-1999  (20,246)
  • 1980-1984  (13,716)
  • 1925-1929
  • 2023  (166)
  • 1996  (20,246)
  • 1983  (13,716)
Collection
Years
  • 2020-2024  (166)
  • 1995-1999  (20,246)
  • 1980-1984  (13,716)
  • 1925-1929
Year
  • 1
    Publication Date: 2023-10-02
    Description: Cold seeps in the deep sea harbor various animals that have adapted to utilize seepage chemicals with the aid of chemosynthetic microbes that serve as primary producers. Corals are among the animals that live near seep habitats and yet, there is a lack of evidence that corals gain benefits and/or incur costs from cold seeps. Here, we focused on Callogorgia delta and Paramuricea sp. type B3 that live near and far from visual signs of currently active seepage at five sites in the deep Gulf of Mexico. We tested whether these corals rely on chemosynthetically-derived food in seep habitats and how the proximity to cold seeps may influence; (i) coral colony traits (i.e., health status, growth rate, regrowth after sampling, and branch loss) and associated epifauna, (ii) associated microbiome, and (iii) host transcriptomes. Stable isotope data showed that many coral colonies utilized chemosynthetically derived food, but the feeding strategy differed by coral species. The microbiome composition of C. delta, unlike Paramuricea sp., varied significantly between seep and non-seep colonies and both coral species were associated with various sulfur-oxidizing bacteria (SUP05). Interestingly, the relative abundances of SUP05 varied among seep and non-seep colonies and were strongly correlated with carbon and nitrogen stable isotope values. In contrast, the proximity to cold seeps did not have a measurable effect on gene expression, colony traits, or associated epifauna in coral species. Our work provides the first evidence that some corals may gain benefits from living near cold seeps with apparently limited costs to the colonies. Cold seeps provide not only hard substrate but also food to cold-water corals. Furthermore, restructuring of the microbiome communities (particularly SUP05) is likely the key adaptive process to aid corals in utilizing seepage-derived carbon. This highlights that those deep-sea corals may upregulate particular microbial symbiont communities to cope with environmental gradients.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2023-10-12
    Description: Due to the strong interconnectedness between the ocean and our societies worldwide, improved ocean governance is essential for sustainable development in the context of the UN Ocean Decade. However, a multitude of different perspectives—ecological, societal, political, economic—and relations between these have to be understood and taken into consideration to foster transformative pathways towards marine sustainability. A core challenge that we are facing is that the ‘right’ response to complex societal issues cannot be known beforehand as abilities to predict complex systems are limited. Consequently, societal transformation is necessarily a journey towards the unknown and therefore requires experimental approaches that must enable the involvement of everyone with stakes in the future of our marine environment and its resources. A promising transdisciplinary research method that fulfils both criteria—being participatory and experimental—are real-world laboratories. Here, we discuss how real-world labs can serve as an operational framework in the context of the Ocean Decade by facilitating and guiding successful knowledge exchange at the interface of science and society. The core element of real-world labs is transdisciplinary experimentation to jointly develop potential strategies leading to targeted real-world interventions, essential for achieving the proposed ‘Decade Outcomes’. The authors specifically illustrate how deploying the concept of real-world labs can be advantageous when having to deal with multiple, overlapping challenges in the context of ocean governance and the blue economy. Altogether, we offer a first major contribution to synthesizing knowledge on the potentials of marine real-world labs, considering how they act as a way of exploring options for sustainable ocean futures. Indeed, in the marine context, real-world labs are still under-explored but are a tangible way for addressing the societal challenges of working towards sustainability transformations over the coming UN Ocean Decade and beyond. Read the free Plain Language Summary for this article on the Journal blog.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2023-09-18
    Description: Coastal ecosystem functioning often hinges on habitat-forming foundation species that engage in positive interactions (e.g. facilitation and mutualism) to reduce environmental stress. Seagrasses are important foundation species in coastal zones but are rapidly declining with losses typically linked to intensifying global change-related environmental stress. There is growing evidence that loss or disruption of positive interactions can amplify coastal ecosystem degradation as it compromises its stress mitigating capacity. Multiple recent studies highlight that seagrass can engage in a facultative mutualistic relationship with lucinid bivalves that alleviate sulphide toxicity. So far, however, the generality of this mutualism, and how its strength and relative importance depend on environmental conditions, remains to be investigated. Here we study the importance of the seagrass-lucinid mutualistic interaction on a continental-scale using a field survey across Europe. We found that the lucinid bivalve Loripes orbiculatus is associated with the seagrasses Zostera noltii and Zostera marina across a large latitudinal range. At locations where the average minimum temperature was above 1 °C, L. orbiculatus was present in 79% of the Zostera meadows; whereas, it was absent below this temperature. At locations above this minimum temperature threshold, mud content was the second most important determinant explaining the presence or absence of L. orbiculatus. Further analyses suggest that the presence of the lucinids have a positive effect on seagrass biomass by mitigating sulphide stress. Finally, results of a structural equation model (SEM) support the existence of a mutualistic feedback between L. orbiculatus and Z. noltii. We argue that this seagrass-lucinid mutualism should be more solidly integrated into management practices to improve seagrass ecosystem resilience to global change as well as the success of restoration efforts.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Publication Date: 2023-09-19
    Description: During the productive polar day, zooplankton and sea-ice amphipods fulfill a critical role in energy transfer from primary producers to higher trophic-level species in Arctic marine ecosystems. Recent polar night studies on zooplankton and sea-ice amphipods suggest higher levels of biological activity than previously assumed. However, it is unknown if these invertebrates maintain polar night activity on stored lipids, opportunistic feeding, or a combination of both. To assess how zooplankton (copepods, amphipods, and krill) and sea-ice amphipods support themselves on seasonally varying resources, we studied their lipid classes, fatty acid compositions, and compound-specific stable isotopes of trophic biomarker fatty acids during polar day (June/July) and polar night (January). Lipid storage and fatty acid results confirm previously described dietary sources in all species during polar day. We found evidence of polar night feeding in all species, including shifts from herbivory to omnivory. Sympagic-, pelagic-, and Calanus spp.-derived carbon sources supported zooplankton and sea-ice amphipods in both seasons. We provide a first indication of polar night feeding of sea-ice amphipods in the pelagic realm.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    Publication Date: 2023-09-22
    Description: The availability of underwater light, as primary energy source for all aquatic photoautotrophs, is (and will further be) altered by changing precipitation, water turbidity, mixing depth, and terrestrial input of chromophoric dissolved organic matter (CDOM). While experimental manipulations of CDOM input and turbidity are frequent, they often involve multiple interdependent changes (light, nutrients, C-supply). To create a baseline for the expected effects of light reduction alone, we performed a weighted meta-analysis on 240 published experiments (from 108 studies yielding 2500 effect sizes) that directly reduced light availability and measured marine autotroph responses. Across all organisms, habitats, and response variables, reduced light led to an average 23% reduction in biomass-related performance, whereas the effect sizes on physiological performance did not significantly differ from zero. Especially, pigment content increased with reduced light, which indicated a strong physiological plasticity in response to diminished light. This acclimation potential was also indicated by light reduction effects minimized if the experiments lasted longer. Nevertheless, the performance (especially biomass accrual) was reduced the more the less light intensity remained available. Light reduction effects were also more negative at higher temperatures if ambient light conditions were poor. Macrophytes or benthic systems were more negatively affected by light reduction than microalgae or plankton systems, especially in physiological responses were microalgae and plankton showed slightly positive responses. Otherwise, the effect magnitudes remained surprisingly consistent across habitats and aspects of experimental design. Therefore, the strong observed log–linear relationship between remaining light and autotrophic performance can be used as a baseline to predict marine primary production in future light climate.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Publication Date: 2023-09-22
    Description: Driven by climate change, marine biodiversity is undergoing a phase of rapid change that has proven to be even faster than changes observed in terrestrial ecosystems. Understanding how these changes in species composition will affect future marine life is crucial for conservation management, especially due to increasing demands for marine natural resources. Here, we analyse predictions of a multiparameter habitat suitability model covering the global projected ranges of 〉33,500 marine species from climate model projections under three CO2 emission scenarios (RCP2.6, RCP4.5, RCP8.5) up to the year 2100. Our results show that the core habitat area will decline for many species, resulting in a net loss of 50% of the core habitat area for almost half of all marine species in 2100 under the high-emission scenario RCP8.5. As an additional consequence of the continuing distributional reorganization of marine life, gaps around the equator will appear for 8% (RCP2.6), 24% (RCP4.5), and 88% (RCP8.5) of marine species with cross-equatorial ranges. For many more species, continuous distributional ranges will be disrupted, thus reducing effective population size. In addition, high invasion rates in higher latitudes and polar regions will lead to substantial changes in the ecosystem and food web structure, particularly regarding the introduction of new predators. Overall, our study highlights that the degree of spatial and structural reorganization of marine life with ensued consequences for ecosystem functionality and conservation efforts will critically depend on the realized greenhouse gas emission pathway.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    Publication Date: 2023-11-16
    Description: Global warming causes dramatic environmental change to Arctic ecosystems. While pelagic primary production is initiated earlier and its intensity can be increased due to earlier ice melt and extended open-water periods, sea-ice primary production is progressively confined on a spatio-temporal scale, leading to unknown consequences for the ice-associated (sympagic) food web. Understanding ecological responses to changes in the availability and composition of pelagic and sympagic food sources is crucial to determine potential changes of food-web structure and functioning in Arctic marine communities under increasingly ice-free conditions. Focus was placed on the importance of suspended particulate organic matter vs. sympagic organic matter for 12 zooplankton species with different feeding modes covering five taxonomic groups (copepods, krill, amphipods, chaetognaths, and appendicularians) at two ice-covered, but environmentally different, stations in the north-western Barents Sea in August 2019. Contributions of diatom- and flagellate-associated fatty acids (FAs) to total lipid content and carbon stable isotopic compositions of these FAs were used to discriminate food sources and trace flows of organic matter in marine food webs. Combination of proportional contributions of FA markers with FA isotopic composition indicated that consumers mostly relied, directly (herbivorous species), or indirectly (omnivorous and carnivorous species), on pelagic diatoms and flagellates, independently of environmental conditions at the sampling locations, trophic position, and feeding mode. Differences were nevertheless observed between species. Contrary to other studies demonstrating a high importance of sympagic organic matter for food-web processes, our results highlight the complexity and variability of trophic structures and dependencies in different Arctic food webs.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Publication Date: 2023-12-19
    Description: Phytoplankton growth is controlled by multiple environmental drivers, which are all modified by climate change. While numerous experimental studies identify interactive effects between drivers, large-scale ocean biogeochemistry models mostly account for growth responses to each driver separately and leave the results of these experimental multiple-driver studies largely unused. Here, we amend phytoplankton growth functions in a biogeochemical model by dual-driver interactions (CO2 and temperature, CO2 and light), based on data of a published meta-analysis on multiple-driver laboratory experiments. The effect of this parametrization on phytoplankton biomass and community composition is tested using present-day and future high-emission (SSP5-8.5) climate forcing. While the projected decrease in future total global phytoplankton biomass in simulations with driver interactions is similar to that in control simulations without driver interactions (5%-6%), interactive driver effects are group-specific. Globally, diatom biomass decreases more with interactive effects compared with the control simulation (-8.1% with interactions vs. no change without interactions). Small-phytoplankton biomass, by contrast, decreases less with on-going climate change when the model accounts for driver interactions (-5.0% vs. -9.0%). The response of global coccolithophore biomass to future climate conditions is even reversed when interactions are considered (+33.2% instead of -10.8%). Regionally, the largest difference in the future phytoplankton community composition between the simulations with and without driver interactions is detected in the Southern Ocean, where diatom biomass decreases (-7.5%) instead of increases (+14.5%), raising the share of small phytoplankton and coccolithophores of total phytoplankton biomass. Hence, interactive effects impact the phytoplankton community structure and related biogeochemical fluxes in a future ocean. Our approach is a first step to integrate the mechanistic understanding of interacting driver effects on phytoplankton growth gained by numerous laboratory experiments into a global ocean biogeochemistry model, aiming toward more realistic future projections of phytoplankton biomass and community composition.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    Publication Date: 2023-12-11
    Description: Phytoplankton are responsible for about 90% of the oceanic primary production, largely supporting marine food webs, and actively contributing to the biogeochemical cycling of carbon. Yet, increasing temperature and pCO2, along with higher dissolved nitrogen: phosphorus ratios in coastal waters are likely to impact phytoplankton physiology, especially in terms of photosynthetic rate, respiration, and dissolved organic carbon (DOC) production. Here, we conducted a full-factorial experiment to identify the individual and combined effects of temperature, pCO2, and N : P ratio on the antioxidant capacity and carbon metabolism of the diatom Phaeodactylum tricornutum. Our results demonstrate that, among these three drivers, temperature is the most influential factor on the physiology of this species, with warming causing oxidative stress and lower activity of antioxidant enzymes. Furthermore, the photosynthetic rate was higher under warmer conditions and higher pCO2, and, together with a lower dark respiration rate and higher DOC exudation, generated cells with lower carbon content. An enhanced oceanic CO2 uptake and an overall stimulated microbial loop benefiting from higher DOC exudation are potential longer-term consequences of rising temperatures, elevated pCO2 as well as shifted dissolved N : P ratios.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    Publication Date: 2023-12-11
    Description: Marine community diversity surveys require a reliable assessment to estimate ecosystem functions and their dynamics. For these, non-invasive environmental DNA (eDNA) metabarcoding is increasingly applied in zoological studies to complement or even replace traditional morphological identification methods. However, uncertainties remain about the accuracy of the diversity detected with eDNA to capture the actual diversity in the field. Here, we validate the reliability of eDNA metabarcoding in identifying metazoan biodiversity in highly dynamic marine waters of the North Sea. We analyzed biodiversity from water (eDNA) and zooplankton samples with cytochrome c oxidase subunit 1 (COI) and 18S rRNA (18S) metabarcoding at Helgoland Roads and validated the optimal molecular resolution by morphological and molecular zooplankton identification (metabarcoding) with the result of merely a few false-negative detections. eDNA and zooplankton metabarcoding resolved 354 species from all major and in total 16 metazoan phyla. This molecular genetic species inventory overlapped by 95.9% (COI) and 81.9% (18S) with published inventories of local, morphologically identified species, among them neozoa and rediscovered species. Even though half of all species were detected by both eDNA and zooplankton metabarcoding, the methods differed significantly in their detected diversity. eDNA metabarcoding performed very well in cnidarians and annelids, whereas zooplankton metabarcoding identified higher numbers of fish and malacostraca. Species assemblages significantly differed between the individual sampling events and the cumulative number of identified species increased steadily over the sampling period and did not reach saturation. About a third of the species were detected only once while a core community of 22 species was identified continuously. Our study confirms eDNA metabarcoding to be a powerful tool to identify and analyze North Sea fauna in highly dynamic waters and we recommend investing in high sampling efforts by repetitive sampling and replication using at least 0.45 μm filters to increase filtration volume.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 11
    Publication Date: 2023-12-20
    Description: Benthic suspension feeders like corals and sponges are important bioengineers in many marine habitats, from the shallow tropics to the depth of polar oceans. While they are generally considered opportunistic, little is known about their actual in situ diet. To tackle this limitation, fatty acid trophic markers (FATMs) have been employed to gain insights into the composition of their diet. Yet, these in situ studies have not been combined with physiological investigations to understand how physiological limitations may modulate the biochemistry of these organisms. Here, we used the cold-water coral (CWC) Desmophyllum dianthus in its natural habitat in Comau Fjord (Northern Patagonia, Chile) as our model species to assess the trophic ecology in response to contrasting physico-chemical conditions (variable vs. stable) and ecological drivers (food availability) at three shallow sites and one deep site. We took advantage of the expression of two distinct phenotypes with contrasting performance (growth, biomass, respiration) coinciding with the differences in sampling depth. We analysed the corals' fatty acid composition to evaluate the utility of FATM profiles to gain dietary insights and assess how performance trade-offs potentially modulate an organism's FATM composition. We found that 20:1(n-9) zooplankton markers dominated the deep high-performance phenotype, while 20:5(n-3) and 22:6(n-3) diatom and flagellate markers, respectively, are more prominent in shallow low-performance phenotype. Surprisingly, both energy stores and performance were higher in the deep phenotype, in spite of measured lower zooplankton availability. Essential FA concentrations were conserved across sites, likely reflecting required levels for coral functioning and survival. While the deep high-performance phenotype met with these requirements, the low-performance phenotype appeared to need more energy to maintain functionality in its highly variable environment, potentially causing intrinsic re-allocations of energy and enrichment in certain essential markers (20:5(n-3), 22:6(n-3)). Our analysis highlights the biological and ecological insights that can be gained from FATM profiles in CWCs, but also cautions the reliability of FATM as diet tracers under limiting environmental conditions that may also be applicable to other marine organisms. Read the free Plain Language Summary for this article on the Journal blog.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 12
    Publication Date: 2024-01-23
    Description: Understanding how community assembly processes drive biodiversity patterns is a \ncentral goal of community ecology. While it is generally accepted that ecological communities are assembled by both stochastic and deterministic processes, quantifying \ntheir relative importance remains challenging. Few studies have investigated how the \nrelative importance of stochastic and deterministic community assembly processes vary \namong taxa and along gradients of habitat degradation. Using data on 1645 arthropod species across seven taxonomic groups in Malaysian Borneo, we quantified the \nimportance of ecological stochasticity and of a suite of community assembly processes \nacross a gradient of logging intensity. The relationship between logging and community assembly varied depending on the specific combination of taxa and stochasticity \nmetric used, but, in general, the processes that govern invertebrate community assembly were remarkably robust to changes in land use intensity.
    Keywords: community assembly ; determinism ; habitat degradation ; logging ; stochasticity
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 13
    Publication Date: 2024-01-22
    Description: Quantifying the abundances of fungi is key to understanding natural variation in mycorrhi-zal communities in relation to plant ecophysiology and environmental heterogeneity. High-throughput metabarcoding approaches have transformed our ability to characterize and com-pare complex mycorrhizal communities. However, it remains unclear how well metabarcodingread counts correlate with actual read abundances in the sample, potentially limiting their useas a proxy for species abundances. Here, we use droplet digital PCR (ddPCR) to evaluate the reliability of ITS2 metabarcodingdata for quantitative assessments of mycorrhizal communities in the orchid speciesNeottiaovatasampled at multiple sites. We performed specific ddPCR assays for eight families oforchid mycorrhizal fungi and compared the results with read counts obtained from metabar-coding. Our results demonstrate a significant correlation between DNA copy numbers measured byddPCR assays and metabarcoding read counts of major mycorrhizal partners ofN. ovata,highlighting the usefulness of metabarcoding for quantifying the abundance of orchid mycor-rhizal fungi. Yet, the levels of correlation between the two methods and the numbers of falsezero values varied across fungal families, which warrants cautious evaluation of the reliabilityof low-abundance families. This study underscores the potential of metabarcoding data for more quantitative analysesof mycorrhizal communities and presents practical workflows for metabarcoding and ddPCRto achieve a more comprehensive understanding of orchid mycorrhizal communities
    Keywords: droplet digital PCR ; fungalquantification ; metabarcoding ; mycorrhizalfungi ; orchid mycorrhiza
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 14
    Publication Date: 2023-02-28
    Description: Hazardous ground deformation and landslides occur frequently in the Mila Basin, Algeria and this problem remains unsolved. However, the historical seismicity in the area indicates no severe damage from past earthquakes. For this reason, studies are needed to monitor the slow ground movements and their triggering factors. Since about two decades ago, satellite observations by interferometric synthetic aperture radar (InSAR) technique and the multi-temporal (MT-InSAR) technique have provided a tool for monitoring slow and extremely slow ground displacements. In this study, 2D decomposition of InSAR outputs revealed a sliding surface at two regions located 12 km apart, indicating slow motion rather than fast movement along the damaged area. We concluded that the factors leading to surface displacement in the investigated area include the triggering earthquakes, precipitation, terrain topography and soil moisture. This study contributes to landslide hazard identification and risk assessment in the Mila Basin.
    Description: Published
    Description: 407–423
    Description: 2T. Deformazione crostale attiva
    Description: JCR Journal
    Keywords: Landslides ; InSAR ; Algeria ; Hazard ; Landslide monitoring using MT-InSAR technique in Algeria
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 15
    Publication Date: 2023-02-28
    Description: The Sicily region (central Mediterranean) is at high risk of drying and desertification caused by current warming and land management. The aim of this study is to place current climatic changes within the past trajectories and natural climatic variability of the Holocene. For this we re‐examine a sediment core retrieved at Lake Pergusa covering the last ca. 6700 years. A multiproxy investigation, and in particular the oxygen isotope composition of lacustrine carbonate (δ18Oc), allowed us to reconstruct decadal‐ to centennial‐scale hydrological changes. The wettest period occurred between ca. 6700 and 6000 cal a BP. The δ18Oc record indicates a new period of wetter conditions between ca. 3700 and 2400 cal a BP. In particular, a δ18Oc minimum between 2850 and 2450 cal a BP overlaps with the period of the ‘Great Solar Minimum’ and corresponds to a dramatic reduction of arboreal pollen (AP%) and to an increase in synanthropic pollen, marking the onset of Greek colonization in the region. The longest driest interval corresponds to the Medieval Climate Anomaly, whereas the highest δ18Oc values are recorded in the last 150 years. The trend of the last 3000 years suggests that, considering future climate projections, the area will experience unprecedented drying exacerbated by human impact.
    Description: Published
    Description: 1280-1293
    Description: 5A. Ricerche polari e paleoclima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 16
    Publication Date: 2023-02-21
    Description: The hinterland of the Cenozoic Northern Apennines fold-and-thrust belt exposes the metamorphic roots of the chain, vestiges of the subduction-related tectono-metamorphic evolution that led to the buildup of the Alpine orogeny in the Mediterranean region. Like in other peri-Mediterranean belts, the tectono-metamorphic evolution of the Palaeozoic continental basement in the Apennines is still poorly constrained, hampering the full understanding of their Alpine orogenic evolution. We report the first comprehensive tectono-metamorphic study of the low-grade metasedimentary (metapsammite/metapelite) succession of the Monti Romani Complex (MRC) that formed after Palaeozoic protoliths and constitutes the southernmost exposure of the metamorphic domain of the Northern Apennines. By integrating fieldwork with microstructural studies, Raman spectroscopy on carbonaceous material and thermodynamic modelling, we show that the MRC preserves a D1/M1 Alpine tectono-metamorphic evolution developed under HP–LT conditions (~1.0–1.1 GPa at T ~ 400°C) during a non-coaxial, top-to-the-NE, crustal shortening regime. Evidence for HP–LT metamorphism is generally cryptic within the MRC, dominated by graphite-bearing assemblages with the infrequent blastesis of muscovite ± chlorite ± chloritoid ± paragonite parageneses, equilibrated under cold palaeo-geothermal conditions (~10°C/km). Results of this study allow extending to the MRC the signature of subduction zone metamorphism already documented in the hinterland of the Apennine orogen, providing further evidence of the syn-orogenic ductile exhumation of the HP units in the Apennine belt. Finally, we discuss the possible role of fluid-mediated changes in the reactive bulk rock composition on mineral blastesis during progress of regional deformation and metamorphism at low-grade conditions.
    Description: Published
    Description: 919-953
    Description: 2TR. Ricostruzione e modellazione della struttura crostale
    Description: JCR Journal
    Keywords: Adria Paleozoic basement ; alpine orogeny ; chloritoid ; subduction metamorphism ; Northern Appennines ; 04.01. Earth Interior
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 17
    Publication Date: 2023-02-28
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Paight, C., Johnson, M., Lasek‐Nesselquist, E., & Moeller, H. Cascading effects of prey identity on gene expression in a kleptoplastidic ciliate. Journal of Eukaryotic Microbiology, 70(1), (2022): e12940, https://doi.org/10.1111/jeu.12940.
    Description: Kleptoplastidic, or chloroplast stealing, lineages transiently retain functional photosynthetic machinery from algal prey. This machinery, and its photosynthetic outputs, must be integrated into the host's metabolism, but the details of this integration are poorly understood. Here, we study this metabolic integration in the ciliate Mesodinium chamaeleon, a coastal marine species capable of retaining chloroplasts from at least six distinct genera of cryptophyte algae. To assess the effects of feeding history on ciliate physiology and gene expression, we acclimated M. chamaeleon to four different types of prey and contrasted well-fed and starved treatments. Consistent with previous physiological work on the ciliate, we found that starved ciliates had lower chlorophyll content, photosynthetic rates, and growth rates than their well-fed counterparts. However, ciliate gene expression mirrored prey phylogenetic relationships rather than physiological status, suggesting that, even as M. chamaeleon cells were starved of prey, their overarching regulatory systems remained tuned to the prey type to which they had been acclimated. Collectively, our results indicate a surprising degree of prey-specific host transcriptional adjustments, implying varied integration of prey metabolic potential into many aspects of ciliate physiology.
    Description: This work was supported by a grant from the Simons Foundation (Award # 689265 to HVM). Research was sponsored by the U.S. Army Research Office and accomplished under contract W911NF-19-D-0001 for the Institute for Collaborative Biotechnologies.
    Keywords: Acquired metabolism ; Cryptophyte ; Mesodinium chamaeleon ; Photophysiology ; Transcriptomics
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 18
    Publication Date: 2023-03-11
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Cones, S., Dent, M., Walkes, S., Bocconcelli, A., DeWind, C., Arjasbi, K., Rose, K., Silva, T., & Sayigh, L. Probable signature whistle production in Atlantic white-sided (Lagenorhynchus acutus) and short-beaked common (Delphinus delphis) dolphins near Cape Cod, Massachusetts. Marine Mammal Science, 39(1), (2022): 338-344, https://doi.org/10.1111/mms.12976.
    Description: Some delphinids produce a learned, individually specific tonal whistle that conveys identity information to conspecifics (Janik & Sayigh, 2013). These whistles, termed signature whistles, were first described by Caldwell and Caldwell (1965) and have been studied intensively over the past several decades (Janik & Sayigh, 2013). In common bottlenose dolphins (Tursiops truncatus) and potentially other species, signature whistles facilitate many ecologically-important behaviors, including individual recognition and maintenance of group cohesion (Janik & Slater, 1998). Additionally, signature whistle contours, or patterns of frequency change over time, can remain stable for several decades, aiding in long-term social bonds (Sayigh et al., 1990). Signature whistles account for approximately 38%–70% of all whistle production in free-swimming animals (Buckstaff, 2004; Cook et al., 2004; Watwood et al., 2005); this percentage can be up to 100% for isolated individuals in captivity (Caldwell et al., 1990). Most of our knowledge on the function and use of signature whistles stems from Tursiops spp., and their use and presence in other delphinid taxa is less understood. Nonetheless, seven additional delphinid species have been reported to produce signature whistles: Indo-Pacific bottlenose dolphins (Tursiops aduncus; Gridley et al., 2014), common dolphins (D. delphis; Caldwell & Caldwell 1968; Fearey et al., 2019), Atlantic spotted dolphins (Stenella plagiodon; Caldwell et al., 1970), Pacific white-sided dolphins (Lagenorhynchus obliquidens; Caldwell & Caldwell, 1973), Pacific humpback dolphins (Sousa chinensis; Van Parijs & Corkeron, 2001), and Guiana dolphins (Sotalia guianensis; Duarte de Figueiredo & Simão, 2009).
    Description: Woods Hole Sea Grant, Woods Hole Oceanographic Institution, Grant/Award Number: NA14OAR4170074
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 19
    Publication Date: 2023-03-24
    Description: Despite their high abundance and diversity, ostracods adapted to a particular chemosynthetic environment and its surroundings have rarely been studied. Therefore, the thresholds and environmental characteristics shaping their assemblages are poorly known. Here, we report a detailed study of the ostracod assemblages occurring around the Zannone Giant Pockmark, a CO2 hydrothermal vent system recently discovered in the central-eastern Tyrrhenian Sea. Although among crustaceans, ostracods seem to have the longest stratigraphic record in fossil seeps and hydrothermal vents starting in the Palaeozoic, our results indicate that their occurrence is driven by CO2 that represents an insurmountable threshold for ostracods’ life.
    Description: Published
    Description: e12698
    Description: 5V. Processi eruttivi e post-eruttivi
    Description: JCR Journal
    Keywords: CaCO3 undersaturated waters ; circalittoral ; hydrothermal vents ; Mediterranean Sea
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 20
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3International Journal of Climatology, Wiley, pp. 1-16, ISSN: 0899-8418
    Publication Date: 2023-05-08
    Description: Owing to the complicated spatial–temporal characteristics of East Asian precipitation (EAP), climate models have limited skills in simulating the modern Asian climate. This consequently leads to large uncertainties in simulations of the past EAP variation and future projections. Here, we explore the performance of the newly developed Alfred Wegener Institute Climate Model,version 3 (AWI-CM3) in simulating the climatological summer EAP. To test whether the model's skill depends on its atmosphere resolution, we design two AWI-CM3 simulations with different horizontal resolutions. The result shows that both simulations have acceptable performance in simulating the summer mean EAP, generally better than the majority of individual models participating in the Coupled Model Intercomparison Project (CMIP6). However, for the monthly EAP from June to August, AWI-CM3 exhibits a decayed skill, which is due to the subseasonal movement of the western Pacific subtropical high bias. The higher-resolution AWI-CM3 simulation shows an overall improvement relative to the one performed at a relatively lower resolution in all aspects taken into account regarding the EAP. We conclude that AWI-CM3 is a suitable tool for exploring the EAP for the observational period. Having verified the model's skill for modern climate, we suggest employing the AWI-CM3, especially with high atmosphere resolution, both for applications in paleoclimate studies and future projections.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 21
    Publication Date: 2023-08-08
    Description: Aim: The distribution of mesoplankton communities has been poorly studied at global scale, especially from in situ instruments. This study aims to (1) describe the global distribution of mesoplankton communities in relation to their environment and (2) as-sess the ability of various environmental- based ocean regionalizations to explain the distribution of these communities. Location: Global ocean, 0–500 m depth. Time Period: 2008–2019. Major Taxa Studied: Twenty-eight groups of large mesoplanktonic and macroplank-tonic organisms, covering Metazoa, Rhizaria and Cyanobacteria. Methods: From a global data set of 2500 vertical profiles making use of the Underwater Vision Profiler 5 (UVP5), an in situ imaging instrument, we studied the global distribu-tion of large (〉600 μm) mesoplanktonic organisms. Among the 6.8 million imaged ob-jects, 330,000 were large zooplanktonic organisms and phytoplankton colonies, the rest consisting of marine snow particles. Multivariate ordination (PCA) and clustering were used to describe patterns in community composition, while comparison with existing regionalizations was performed with regression methods (RDA). Results: Within the observed size range, epipelagic plankton communities were Trichodesmium- enriched in the intertropical Atlantic, Copepoda- enriched at high latitudes and in upwelling areas, and Rhizaria-enriched in oligotrophic areas. In the mesopelagic layer, Copepoda-enriched communities were also found at high lati-tudes and in the Atlantic Ocean, while Rhizaria-enriched communities prevailed in the Peruvian upwelling system and a few mixed communities were found elsewhere. The comparison between the distribution of these communities and a set of existing regionalizations of the ocean suggested that the structure of plankton communities described above is mostly driven by basin- level environmental conditions. Main Conclusions: In both layers, three types of plankton communities emerged and seemed to be mostly driven by regional environmental conditions. This work sheds light on the role not only of metazoans, but also of unexpected large protists and cy-anobacteria in structuring large mesoplankton communities.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 22
    Publication Date: 2023-08-09
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 23
    Publication Date: 2023-08-28
    Description: Ice wedge polygons on steep slopes have generally been described as being covered by periglacial sediments and, typically, the active layer on slopes becomes mobile during thaw periods, which can lead to solifluction. In West Greenland close to the ice margin, however, the active layer and ice wedge polygons are stable despite their occurrence on steep slopes with inclinations of ≥30°. We conducted a soil survey (including sampling for soil analyses and radiocarbon dating) in the Umimmalissuaq valley and installed a field station ~4 km east of the current ice margin to monitor soil temperature and water tension at depths of 10, 20 and 35 cm of the active layer on a steep, north-facing slope in the middle of an ice wedge polygon from 2009 to 2015. Thawing and freezing periods lasted between 2 and 3 months and the active layer was usually completely frozen from November to April. We observed simultaneous and complete water saturation at all three depths of the active layer in one summer for 1 day. The amount of water in the active layer apparently was not enough to trigger solifluction during the summer thaw, even at slope inclinations above 30°. In addition, the dense shrub tundra absorbs most of the water during periods between thawing and freezing, which further stabilizes the slope. This process, together with the dry and continental climate caused by katabatic winds combined with no or limited frost heave, plays a crucial role in determining the stability of these slopes and can explain the presence of large-scale stable ice wedge polygon networks in organic matter-rich permafrost, which is about 5,000 years old. This study underlines the importance of soil hydrodynamics and local climate regime for landscape stability and differing intensities of solifluction processes in areas with strong geomorphological gradients and rising air temperatures.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 24
    Publication Date: 2023-08-29
    Description: Growth rates and other biomass traits of phytoplankton are strongly affected by temperature. We hypothesized that resulting phenotypes originate from deviating temperature sensitivities of underlying physiological processes. We used membrane-inlet mass spectrometry to assess photosynthetic and respiratory O2 and CO2 fluxes in response to abrupt temperature changes as well as after acclimation periods in the diatom Phaeodactylum tricornutum. Abrupt temperature changes caused immediate over- or undershoots in most physiological processes, that is, photosynthetic oxygen release ((Figure presented.)), photosynthetic carbon uptake ((Figure presented.)), and respiratory oxygen release ((Figure presented.)). Over acclimation timescales, cells were, however, able to re-adjust their physiology and revert to phenotypic ‘sweet spots’. Respiratory CO2 release ((Figure presented.)) was generally inhibited under high temperature and stimulated under low-temperature settings, on abrupt as well as acclimation timescales. Such behavior may help mitochondria to stabilize plastidial ATP : NADPH ratios and thus maximize photosynthetic carbon assimilation.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 25
    Publication Date: 2023-02-21
    Description: © The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Jenouvrier, S., Aubry, L., van Daalen, S., Barbraud, C., Weimerskirch, H., & Caswell, H. When the going gets tough, the tough get going: effect of extreme climate on an Antarctic seabird’s life history. Ecology Letters, 25, (2022): 2120– 2131, https://doi.org/10.1111/ele.14076.
    Description: Individuals differ in many ways. Most produce few offspring; a handful produce many. Some die early; others live to old age. It is tempting to attribute these differences in outcomes to differences in individual traits, and thus in the demographic rates experienced. However, there is more to individual variation than meets the eye of the biologist. Even among individuals sharing identical traits, life history outcomes (life expectancy and lifetime reproduction) will vary due to individual stochasticity, that is to chance. Quantifying the contributions of heterogeneity and chance is essential to understand natural variability. Interindividual differences vary across environmental conditions, hence heterogeneity and stochasticity depend on environmental conditions. We show that favourable conditions increase the contributions of individual stochasticity, and reduce the contributions of heterogeneity, to variance in demographic outcomes in a seabird population. The opposite is true under poor conditions. This result has important consequence for understanding the ecology and evolution of life history strategies.
    Description: We acknowledge Institute Paul Emile Victor (Programme IPEV 109), and Terres Australes et Antarctiques Françaises for logistical and financial support in Terre Adélie. The study is a contribution to the Program EARLYLIFE funded by a European Research Council Advanced Grant under the European Community's Seven Framework Program FP7/2007-2013 (Grant Agreement ERC-2012-ADG_20120314 to Henri Weimerskirch), to the program SENSEI funded by the BNP Paribas Foundation, and to the Program INDSTOCH funded by ERC Advanced Grant 322989 to Hal Caswell. SJ acknowledges support from Ocean Life Institute and WHOI Unrestricted funds, and NSF projects DEB-1257545, OPP-1246407 and OPP-1840058.
    Keywords: Fixed heterogeneity ; Frailty ; Individual quality ; Individual stochasticity ; Unobserved individual heterogeneity ; SICs
    Repository Name: Woods Hole Open Access Server
    Type: Article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 26
    Publication Date: 2023-04-14
    Description: Thermokarst lagoons represent the transition state from a freshwater lacustrine to a marine environment, and receive little attention regarding their role for greenhouse gas production and release in Arctic permafrost landscapes. We studied the fate of methane (CH4) in sediments of a thermokarst lagoon in comparison to two thermokarst lakes on the Bykovsky Peninsula in northeastern Siberia through the analysis of sediment CH4 concentrations and isotopic signature, methane-cycling microbial taxa, sediment geochemistry, lipid biomarkers, and network analysis. We assessed how differences in geochemistry between thermokarst lakes and thermokarst lagoons, caused by the infiltration of sulfate-rich marine water, altered the microbial methane-cycling community. Anaerobic sulfate-reducing ANME-2a/2b methanotrophs dominated the sulfate-rich sediments of the lagoon despite its known seasonal alternation between brackish and freshwater inflow and low sulfate concentrations compared to the usual marine ANME habitat. Non-competitive methylotrophic methanogens dominated the methanogenic community of the lakes and the lagoon, independent of differences in porewater chemistry and depth. This potentially contributed to the high CH4 concentrations observed in all sulfate-poor sediments. CH4 concentrations in the freshwater-influenced sediments averaged 1.34 ± 0.98 μmol g−1, with highly depleted δ13C-CH4 values ranging from −89‰ to −70‰. In contrast, the sulfate-affected upper 300 cm of the lagoon exhibited low average CH4 concentrations of 0.011 ± 0.005 μmol g−1 with comparatively enriched δ13C-CH4 values of −54‰ to −37‰ pointing to substantial methane oxidation. Our study shows that lagoon formation specifically supports methane oxidizers and methane oxidation through changes in pore water chemistry, especially sulfate, while methanogens are similar to lake conditions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 27
    Publication Date: 2023-03-16
    Description: Active hydrothermal travertine systems are ideal environments to investigate how abiotic and biotic processes affect mineralization mechanisms and mineral fabric formation. In this study, a biogeochemical characterization of waters, dissolved gases, and microbial mats was performed together with a mineralogical investigation on travertine encrustations occurring at the outflow channel of a thermal spring. The comprehensive model, compiled by means of TOUGHREACT computational tool from measured parameters, revealed that mineral phases were differently influenced by either abiotic conditions or microbially driven processes. Microbial mats are shaped by light availability and temperature gradient of waters flowing along the channel. Mineralogical features were homogeneous throughout the system, with euhedral calcite crystals, related to inorganic precipitation induced by CO2 degassing, and calcite shrubs associated with organomineralization processes, thus indicating an indirect microbial participation to the mineral deposition (microbially influenced calcite). The microbial activity played a role in driving calcite redissolution processes, resulting in circular pits on calcite crystal surfaces possibly related to the metabolic activity of sulfur-oxidizing bacteria found at a high relative abundance within the biofilm community. Sulfur oxidation might also explain the occurrence of gypsum crystals embedded in microbial mats, since gypsum precipitation could be induced by a local increase in sulfate concentration mediated by S-oxidizing bacteria, regardless of the overall undersaturated environmental conditions. Moreover, the absence of gypsum dissolution suggested the capability of microbial biofilm in modulating the mobility of chemical species by providing a protective envelope on gypsum crystals.
    Description: Published
    Description: 837-856
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: biofilms; gypsum; hot spring; microbial mat; travertine
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 28
    Publication Date: 2023-06-12
    Description: While understanding feeding preferences of herbivores and carnivores is of major importance in ecology, we still know very little on the sensitivity of different functional groups to suboptimal stoichiometric resource quality. Here, we apply concepts of ecological stoichiometry to shed light on differences in the nutritional requirements of herbivores and carnivores, and to make predictions on the influence of suboptimal resource stoichiometric quality on the fitness of these different consumers to. Herbivores generally experience more variation in the quality of their resource than carnivores do, and these differences have likely shaped the extent to which coping mechanisms have evolved. Consequently, we expect 1) herbivores to maintain their stoichiometric homeostasis over a broader range of resource stoichiometry than carnivores, 2) the threshold elemental ratio (TER), i.e. the dietary carbon to nutrient ratio which maximizes fitness, of herbivores to be higher than that of carnivores, 3) a narrower and sharper knife-edge response in carnivores than herbivores and 4) asymmetric knife-edge responses indicating a higher sensitivity to the diet quality that consumers are not used to dealing with, namely nutrient limitation in carnivores and nutrient excess in herbivores. Our study poses that documenting the ranges of resource quality where consumer fitness declines in diverse organisms is a very promising avenue to increase our understanding of community composition and food web functioning.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 29
    Publication Date: 2023-06-21
    Description: Interoceanic canals can facilitate biological invasions as they connect the world's oceans and remove dispersal barriers between bioregions. As a consequence, multiple opportunities for biotic exchange arise and the resulting establishment of migrant species often causes adverse ecological and economic impacts. The Panama Canal is a key region for biotic exchange as it connects the Pacific and Atlantic Oceans in Central America. In this study, we used two complementary methods (environmental DNA (eDNA) metabarcoding and gillnetting) to survey fish communities in this unique waterway. Using COI (cytochrome oxidase subunit I) metabarcoding, we detected a total of 142 fish species, including evidence for the presence of sixteen Atlantic and eight Pacific marine fish in different freshwater sections of the Canal. Of these, nine are potentially new records. Molecular data did not capture all species caught with gillnets, but generally provided a more complete image of the known fish fauna as more small-bodied fish species were detected. Diversity indices based on eDNA surveys revealed significant differences across different sections of the Canal reflecting in part the prevailing environmental conditions. The observed increase in the presence of marine fish species in the Canal indicates a growing potential for interoceanic fish invasions. The potential ecological and evolutionary consequences of this increase in marine fishes are not only restricted to the fish fauna in the Canal as they could also impact adjacent ecosystems in the Pacific and Atlantic Oceans.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 30
    Publication Date: 2023-05-25
    Description: A recent discovery of a Bronze Age harbor site in Çamçalık provides new data for the relative sea level history along the coast of the Bozburun Peninsula over the last 3600 years. In this study, we compared the new and previously published data from nearby sites to determine the long-term relative sea level changes. Further comparison of the observed sea level data and newly produced glacial isostatic adjustment (GIA) models clarified the tectonic contribution to the relative sea level changes. Our results suggest a nonlinear tectonic subsidence trend in the coastal zone since 3600 B.P. The increase in the relative sea level accelerated over the last 1400 years, mostly due to the seismic events controlled by the tectonic regime of the southeastern Aegean Sea. We can conclude that, as in the past, this active tectonic process will have a major impact on the future sea level evolution of the coastal sector of the Bozburun Peninsula. Notably, our study can be used to understand the historical trend of sea level rise while providing a foundation for future trend prediction.
    Description: Published
    Description: 246-260
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 31
    Publication Date: 2023-07-10
    Description: The Pliocene Epoch (∼5.3-2.6 million years ago, Ma) was characterized by a warmer than present climate with smaller Northern Hemisphere ice sheets, and offers an example of a climate system in long-term equilibrium with current or predicted near-future atmospheric CO2 concentrations (pCO2). A long-term trend of ice-sheet expansion led to more pronounced glacial (cold) stages by the end of the Pliocene (∼2.6 Ma), known as the “intensification of Northern Hemisphere Glaciation” (iNHG). We assessed the spatial and temporal variability of ocean temperatures and ice-volume indicators through the late Pliocene and early Pleistocene (from 3.3 to 2.4 Ma) to determine the character of this climate transition. We identified asynchronous shifts in long-term means and the pacing and amplitude of shorter-term climate variability, between regions and between climate proxies. Early changes in Antarctic glaciation and Southern Hemisphere ocean properties occurred even during the mid-Piacenzian warm period (∼3.264-3.025 Ma) which has been used as an analogue for future warming. Increased climate variability subsequently developed alongside signatures of larger Northern Hemisphere ice sheets (iNHG). Yet, some regions of the ocean felt no impact of iNHG, particularly in lower latitudes. Our analysis has demonstrated the complex, non-uniform and globally asynchronous nature of climate changes associated with the iNHG. Shifting ocean gateways and ocean circulation changes may have pre-conditioned the later evolution of ice sheets with falling atmospheric pCO2. Further development of high-resolution, multi-proxy reconstructions of climate is required so that the full potential of the rich and detailed geological records can be realized.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 32
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3PAMM, Wiley, 22(1), ISSN: 1617-7061
    Publication Date: 2023-10-24
    Description: 〈jats:title〉Abstract〈/jats:title〉〈jats:p〉Ice shelves are large floating ice masses, that are formed when glaciers are becoming afloat at the margin of ice sheets. One dominating mass loss mechanism of ice shelves is calving, describing the detachment of icebergs at the front. Ice shelves stabilize inland ice glaciers due to buttressing. If the stabilizing effect of an ice shelf vanishes because of disintegration or thinning, the corresponding glacier accelerates resulting in sea level rise.〈/jats:p〉〈jats:p〉To describe calving and disintegration of ice shelves, it is important to investigate fracture propagation in ice. A powerful method in fracture mechanics is the phase field method which is based on Griffith's theory. It approximates cracks in a diffuse manner by using a continuous scalar field. We propose a phase field fracture model for ice considering its characteristic material properties. The material behavior of ice depends on the considered time scales. On short time scales it behaves like a solid and while it acts like a fluid on long time scales, which classifies it as a viscoelastic material of Maxwell type. This has been verified by observations. The phase field method allows us to simulate typical fracture situations of ice shelves in Antarctica and Greenland.〈/jats:p〉
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 33
    Publication Date: 2023-10-23
    Description: Morphological identification of cnidarian species can be difficult throughout all life stages due to the lack of distinct morphological characters. Moreover, in some cnidarian taxa genetic markers are not fully informative, and in these cases combinations of different markers or additional morphological verifications may be required. Proteomic fingerprinting based on MALDI-TOF mass spectra was previously shown to provide reliable species identification in different metazoans including some cnidarian taxa. For the first time, we tested the method across four cnidarian classes (Staurozoa, Scyphozoa, Anthozoa, Hydrozoa) and included different scyphozoan life-history stages (polyp, ephyra, medusa) in our dataset. Our results revealed reliable species identification based on MALDI-TOF mass spectra across all taxa with species-specific clusters for all 23 analysed species. In addition, proteomic fingerprinting was successful for distinguishing developmental stages, still by retaining a species specific signal. Furthermore, we identified the impact of different salinities in different regions (North Sea and Baltic Sea) on proteomic fingerprints to be negligible. In conclusion, the effects of environmental factors and developmental stages on proteomic fingerprints seem to be low in cnidarians. This would allow using reference libraries built up entirely of adult or cultured cnidarian specimens for the identification of their juvenile stages or specimens from different geographic regions in future biodiversity assessment studies.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 34
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Frontiers in Ecology and the Environment, Wiley, 21(5), pp. 227-233, ISSN: 1540-9295
    Publication Date: 2023-10-23
    Description: Sea ice is crucial for breeding in true Antarctic pinnipeds. Although critical to interpret and mitigate the effects of extreme climatic events on polar species, knowledge of the effects of strong sea-ice anomalies on the reproductive activity of true Antarctic pinnipeds is scarce. Underwater vocalizations in these species play a key role in reproduction and function as indicators for presence and breeding onset. Using 8 years of recordings, we quantified the effect of sea-ice concentration and drift on the acoustic presence probability of four pinniped species in their breeding areas. In all four species, acoustic activity timing was constant across years, but decreased when sea-ice cover conditions were 〈10%, suggesting that individuals may fail to anticipate rapid changes in sea-ice cover. In the species’ traditional breeding areas, extreme and regular negative anomalies in early austral-summer sea ice could affect long-term reproductive success. Our findings underscore the urgent need for a better understanding of climate-driven changes in high-fidelity breeding areas to mitigate current and future anthropogenic pressures, and to sustain the integrity and functionality of the Southern Ocean's ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 35
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Frontiers in Ecology and the Environment, Wiley, 21(5), pp. 227-233, ISSN: 1540-9295
    Publication Date: 2023-10-23
    Description: Sea ice is crucial for breeding in true Antarctic pinnipeds. Although critical to interpret and mitigate the effects of extreme climatic events on polar species, knowledge of the effects of strong sea-ice anomalies on the reproductive activity of true Antarctic pinnipeds is scarce. Underwater vocalizations in these species play a key role in reproduction and function as indicators for presence and breeding onset. Using 8 years of recordings, we quantified the effect of sea-ice concentration and drift on the acoustic presence probability of four pinniped species in their breeding areas. In all four species, acoustic activity timing was constant across years, but decreased when sea-ice cover conditions were 〈10%, suggesting that individuals may fail to anticipate rapid changes in sea-ice cover. In the species’ traditional breeding areas, extreme and regular negative anomalies in early austral-summer sea ice could affect long-term reproductive success. Our findings underscore the urgent need for a better understanding of climate-driven changes in high-fidelity breeding areas to mitigate current and future anthropogenic pressures, and to sustain the integrity and functionality of the Southern Ocean's ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 36
    Publication Date: 2023-10-23
    Description: Species identification is pivotal in biodiversity assessments and proteomic fingerprinting by MALDI-TOF mass spectrometry has already been shown to reliably identify calanoid copepods to species level. However, MALDI-TOF data may contain more information beyond mere species identification. In this study, we investigated different ontogenetic stages (copepodids C1–C6 females) of three co-occurring Calanus species from the Arctic Fram Strait, which cannot be identified to species level based on morphological characters alone. Differentiation of the three species based on mass spectrometry data was without any error. In addition, a clear stage-specific signal was detected in all species, supported by clustering approaches as well as machine learning using Random Forest. More complex mass spectra in later ontogenetic stages as well as relative intensities of certain mass peaks were found as the main drivers of stage distinction in these species. Through a dilution series, we were able to show that this did not result from the higher amount of biomass that was used in tissue processing of the larger stages. Finally, the data were tested in a simulation for application in a real biodiversity assessment by using Random Forest for stage classification of specimens absent from the training data. This resulted in a successful stage-identification rate of almost 90%, making proteomic fingerprinting a promising tool to investigate polewards shifts of Atlantic Calanus species and, in general, to assess stage compositions in biodiversity assessments of Calanoida, which can be notoriously difficult using conventional identification methods.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 37
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Scandinavian Journal of Economics, Wiley, 125(2), pp. 403-440, ISSN: 0347-0520
    Publication Date: 2023-10-23
    Description: We analyse the two-dimensional Nash bargaining solution (NBS) by deploying the standard labour market negotiations model of McDonald and Solow. We show that the two-dimensional bargaining problem can be decomposed into two one-dimensional problems, such that the two solutions together replicate the solution of the two-dimensional problem if the NBS is applied. The axiom of “independence of irrelevant alternatives” is shown to be crucial for this type of decomposability. This result has significant implications for actual negotiations because it allows for the decomposition of a multi-dimensional bargaining problem into one-dimensional problems – and thus helps to facilitate real-world negotiations.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 38
    Publication Date: 2023-07-06
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 39
    Publication Date: 2023-11-15
    Description: 〈jats:title〉ABSTRACT〈/jats:title〉〈jats:p〉Ooids are abundant carbonate grains throughout much of Earth's history, but their formation is not well understood. Here, an in‐depth study of microbial bioerosion features of Holocene ooids from the Schooner Cays ooid shoals (Great Bahama Bank, Eleuthera, Bahamas) and the Shalil al Ud ooid shoals in the Gulf (Abu Dhabi, United Arab Emirates) is presented. No obvious differences were found in ooid size distribution, cortex layer thickness, the composition of nuclei or euendolithic community when comparing ooids from both locations. Microendolithic borings are present in most studied ooid surfaces, but the intensity of (micro‐)bioerosion varies significantly. Applying an epoxy vacuum cast‐embedding technique allowed the identification of ichnotaxa and their inferred producers (various genera of diatoms, cyanobacteria, coccolithophores and unspecified bacteria). Euendolithic taxa have specific low‐light tolerances and light optima. This implies that information about the relative bathymetry (seafloor versus burial within an ooid shoal) and ecology for ooid cortex formation can be obtained via the presence or absence of their respective ichnotaxa. The history of a statistically significant number of ooid cortices can be translated into dune dynamics and the temporal variations thereof by allocating the inferred index producer to a defined burial or light penetration zone. In this context, ooid formation can be divided into four stages: (i) an agitation stage in the water column, characterized by the colonization of grains by photoautotrophs; (ii) a resting stage, characterized by temporary burial of the ooid, leading to immobilization and a shift towards heterotrophs; (iii) a sleeping stage, characterized by prolonged burial and colonialization by organotrophs; and (iv) a reactivation stage, characterized by a resurfacing of the ooid and a subsequent shift towards photoautotrophs. The sleeping stage is presumably a stage of ooid degradation where bioerosion, mainly by heterotrophic fungi and bacteria is particularly active.〈/jats:p〉
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 40
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Oikos, Wiley, ISSN: 0030-1299
    Publication Date: 2023-09-27
    Description: 〈jats:p〉Compositional measurements from species assemblages define a high dimensional dataspace in which the data can form complex structures, termed manifolds. Comparing assemblages in this dataspace is difficult because the data is often sparse relative to its dimensionality and the complex structure of the manifold introduces bias and error in measurements of distance. Here, we apply diffusion maps, a manifold learning method, to find and characterize manifolds in high‐dimensional compositional data. We show that diffusion maps embed the data in reduced dimensions in which the Euclidean distance between data points approximates the distance between them along the manifold. This is especially useful when species turnover is high, as it provides a way to measure meaningful distances between assemblages even when they harbor disjoint sets of species. We anticipate diffusion maps will therefore be particularly useful for characterizing community change over large spatial and temporal scales.〈/jats:p〉
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 41
    Publication Date: 2024-01-24
    Description: 〈jats:title〉Abstract〈/jats:title〉〈jats:p〉Phages depend on their bacterial hosts to replicate. The habitat, density and genetic diversity of host populations are therefore key factors in phage ecology, but our ability to explore their biology depends on the isolation of a diverse and representative collection of phages from different sources. Here, we compared two populations of marine bacterial hosts and their phages collected during a time series sampling program in an oyster farm. The population of 〈jats:italic〉Vibrio crassostreae〈/jats:italic〉, a species associated specifically to oysters, was genetically structured into clades of near clonal strains, leading to the isolation of closely related phages forming large modules in phage–bacterial infection networks. For 〈jats:italic〉Vibrio chagasii〈/jats:italic〉, which blooms in the water column, a lower number of closely related hosts and a higher diversity of isolated phages resulted in small modules in the phage–bacterial infection network. Over time, phage load was correlated with 〈jats:italic〉V. chagasii〈/jats:italic〉 abundance, indicating a role of host blooms in driving phage abundance. Genetic experiments further demonstrated that these phage blooms can generate epigenetic and genetic variability that can counteract host defence systems. These results highlight the importance of considering both the environmental dynamics and the genetic structure of the host when interpreting phage–bacteria networks.〈/jats:p〉
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 42
    Publication Date: 2024-01-23
    Description: Against the background of the UN decade on ecosystem restoration and the new EU Biodiversity Strategy for 2030, and in the context of marine spatial planning and complex maritime user conflicts, reliable information on habitat suitability for large-scale restoration is an important prerequisite for implementing conservation management and for supporting successful, sustainable, and ecologically efficient restoration measures. In this study, habitat suitability was assessed using multicriteria decision analysis (MCDA) for the restoration of the European oyster, Ostrea edulis, in marine protected areas (MPAs) of the German Bight in the North Sea: Borkum Reef Ground (Borkum Riffgrund, BRG) and Sylt Outer Reef – Eastern German Bight (Sylter Außenriff, SAR). Based on site selection criteria, exclusion and suitability factors for the MCDA were defined. Results were integrated with the available geodata to produce habitat suitability maps for oyster restoration in the area of interest. Suitable as well as unsuitable habitats have been successfully identified for both MPAs: several hundred square kilometres (≥97.2% of BRG) or several thousand square kilometres (≥74.5% of SAR) were classified as ecologically and logistically suitable for oyster restoration measures in the respective MPAs. As oyster restoration is significantly limited by human activities (e.g. bottom trawl fisheries), the management of fisheries is an important prerequisite for successful oyster restoration in both MPAs. Results show that designated fishery management measures will increase the possibilities for oyster restoration. In BRG, our results correspond to the known historical distribution. In SAR, our results significantly exceed the historically known distribution. The habitat suitability analysis will facilitate decision-making regarding ocean use, and will reduce restoration costs through targeted management activities in areas of high suitability and expand species recovery by improving the survival of reintroduced individuals. The habitat suitability analysis procedure is easily adaptable for application to other areas, other species, or other habitat restoration projects, or to other conservation management settings. The software applied is open source and the suitability calculation is described in detail to inform wider applications.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 43
    Publication Date: 2024-03-21
    Description: Protist plankton are major members of open-water marine food webs. Traditionally divided between phototrophic phytoplankton and phagotrophic zooplankton, recent research shows many actually combine phototrophy and phagotrophy in the one cell; these protists are the “mixoplankton.” Under the mixoplankton paradigm, “phytoplankton” are incapable of phagotrophy (diatoms being exemplars), while “zooplankton” are incapable of phototrophy. This revision restructures marine food webs, from regional to global levels. Here, we present the first comprehensive database of marine mixoplankton, bringing together extant knowledge of the identity, allometry, physiology, and trophic interactivity of these organisms. This mixoplankton database (MDB) will aid researchers that confront difficulties in characterizing life traits of protist plankton, and it will benefit modelers needing to better appreciate ecology of these organisms with their complex functional and allometric predator–prey interactions. The MDB also identifies knowledge gaps, including the need to better understand, for different mixoplankton functional types, sources of nutrition (use of nitrate, prey types, and nutritional states), and to obtain vital rates (e.g. growth, photosynthesis, ingestion, factors affecting photo’ vs. phago’ -trophy). It is now possible to revisit and re-classify protistan “phytoplankton” and “zooplankton” in extant databases of plankton life forms so as to clarify their roles in marine ecosystems.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 44
    Publication Date: 2024-03-22
    Description: We assessed the responses of solitary cells of Arctic Phaeocystis pouchetii grown under a matrix of temperature (2°C vs. 6°C), light intensity (55 vs. 160 μmol photons m−2 s−1) and pCO2 (400 vs. 1000 μatm CO2, i.e., 40.5 vs. 101.3 Pa). Next to acclimation parameters (growth rates, particulate and dissolved organic C and N, Chlorophyll a content), we measured physiological processes in vivo (electron transport rates and net photosynthesis) using fast-repetition rate fluorometry and membrane-inlet mass spectrometry. Within the applied driver ranges, elevated temperature had the most pronounced impacts, significantly increasing growth, elemental quotas and photosynthetic performance. Light stimulations manifested more prominently under 6°C, underlining temperature's role as a “master-variable”. pCO2 was the least effective driver, exerting mostly insignificant effects. The obtained data were used for a simplistic upscaling simulation to investigate potential changes in P. pouchetii's bloom dynamics in the Fram Strait with increasing temperatures over the 21st century. Although solitary cells might not be fully representative of colonial cells commonly observed in the field, our results suggest that global warming accelerates bloom dynamics, with earlier onsets of blooms and higher peak biomasses. Such a temperature-induced acceleration in the phenology of Phaeocystis and likely other Arctic phytoplankton might cause temporal mismatches, e.g., with the development of grazers, and therefore substantially affect the biogeochemistry and ecology of the Arctic.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 45
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Aquatic Conservation Marine and Freshwater Ecosystems, Wiley, 33(7), pp. 661-677, ISSN: 1052-7613
    Publication Date: 2024-03-22
    Description: Ecological restoration includes specific technical phases over the course of an ecosystem recovery process. In the marine environment and for oyster reef restoration, the installation and implementation of pilot reefs close the gap between feasibility studies with small-scale experiments and designated upscaling for marine conservation measures. Against this background, this study presents the design, planning and installation of the first pilot oyster reef in offshore sublittoral regions of the North Sea. The work was conducted as part of marine protected area management in the Natura 2000 site Borkum Reef Ground in the German Bight, in the area of historical offshore oyster grounds. It includes logistical considerations, material selection, methodology for reef base construction and deployment of European flat oysters Ostrea edulis as spat-on-shell, young and adult single seed oysters, and spat-on-reef, as well as the development of an efficient monitoring approach for reef-associated biodiversity. Native Oyster Restoration Alliance monitoring methodologies, such as underwater visual census and seabed images were selected, tested and successfully adapted for the pilot oyster reef and study site. The evaluation and optimization of offshore sublittoral oyster reef monitoring are presented here, and biodiversity metrics are put into perspective with data from recent and historical studies. Results show a few mobile fauna species (e.g., fish and decapods) as first colonizers after reef construction. One year later, biodiversity increased due to a larger number of invertebrate and fish species. However, the pilot oyster reef community still represents an early recolonization stage, with lower biodiversity than historical records. This study presents a proof of concept for the design, planning and construction of an offshore oyster reef and indicates stages in the recovery process. Strategies to optimize and to complement reef-monitoring in challenging environments are discussed, emphasizing additional molecular and functional analyses for future assessments.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 46
    Publication Date: 2024-02-08
    Description: Copepods are the most abundant metazoans on Earth, driving cycles of key elements in aquatic systems, most prominently carbon (C), nitrogen (N), and phosphorus (P). One key factor determining nutrient cycling is copepod somatic stoichiometry, which can reflect ecological strategy. We conducted a systematic review that updates the seminal work of Båmstedt (1986) by summarizing the effects of latitude, habitat, life history stage, and taxonomy on C:N, C:P, and N:P ratios of field-collected copepods. We found that differences among copepod families accounted for the greatest variation, with the Rhincalanidae and Diaptomidae being particularly C-rich, while the Calanidae were more N- and P-rich. Copepod C:N was higher in inland waters compared with animals from marine environments in both copepodites and adult females, matching the higher C content of seston in many inland freshwaters. For both copepodites and adult females, mid-latitude animals had higher C:N and C:P than high-latitude animals, which matched predictions based on the availability of nutrients or adaptation to cold environments. More data must be gathered to fill gaps in our knowledge of copepod stoichiometry, focusing particularly on younger life stages, non-calanoids, low and high latitudes, the southern hemisphere, and estuarine and some inland water habitats, including large lakes. Such information will help better parameterize models of aquatic ecosystems and improve our understanding of how copepods influence consumer-driven nutrient cycling and food web dynamics.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 47
    Publication Date: 2024-02-15
    Description: With declining biodiversity worldwide, a better understanding of species diversity and their relationships is imperative for conservation and management efforts. Marine sponges are species-rich ecological key players on coral reefs, but their species diversity is still poorly understood. This is particularly true for the demosponge order Haplosclerida, whose systematic relationships are contentious due to the incongruencies between morphological and molecular phylogenetic hypotheses. The single gene markers applied in previous studies did not resolve these discrepancies. Hence, there is a high need for a genome-wide approach to derive a phylogenetically robust classification and understand this group\'s evolutionary relationships. To this end, we developed a target enrichment-based multilocus probe assay for the order Haplosclerida using transcriptomic data. This probe assay consists of 20,000 enrichment probes targeting 2956 ultraconserved elements in coding (i.e. exon) regions across the genome and was tested on 26 haplosclerid specimens from the Red Sea. Our target-enrichment approach correctly placed our samples in a well-supported phylogeny, in agreement with previous haplosclerid molecular phylogenies. Our results demonstrate the applicability of high-resolution genomic methods in a systematically complex marine invertebrate group and provide a promising approach for robust phylogenies of Haplosclerida. Subsequently, this will lead to biologically unambiguous taxonomic revisions, better interpretations of biological and ecological observations and new avenues for applied research, conservation and managing declining marine diversity.
    Keywords: bait design ; exon ; phylogenetic markers ; target capture ; ultraconserved element
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
    Format: application/pdf
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 48
    Publication Date: 2024-04-10
    Description: Sedimentary ancient DNA (sedaDNA) has proven to be a useful tool for palaeoenvironmental studies, but only a handful of studies exist so far for tropical regions. In this study we used sedaDNA to study the temporal succession of Brachionus spp. rotifer mitochondrial DNA haplotypes using two sediment cores from two climatically different alkaline-saline crater lakes from the Kenyan Rift Valley. Data were retrieved from a sediment core (dating back to AD 1800) from Lake Kageinya, located in the remote, hot and hyper-arid Suguta Valley. sedaDNA was used to study the temporal succession of mitochondrial DNA haplotypes of Brachionus spp. rotifers. The results were compared to previously published data from Lake Sonachi, a well-studied lake in the humid and colder mountainous region of Kenya near the town of Naivasha, now supported by a 210Pb age chronology. Both records extend back before the onset of substantial anthropogenic impact in these regions. The results revealed that climate—rather than anthropogenic impact—was most strongly correlated with haplotype changes in both lakes. During prolonged dry periods (such as from AD 1910 to the late AD 1960s), certain haplotypes persisted. Sudden changes and the emergence of alter native haplotypes were observed when climate became more humid or during episodes of highly variable climate (before AD 1910 and from AD 1960s onwards). Progressive changes in prevailing haplotypes during periods with variable climate could reflect local adaptation and/or be the result of immigration of new haplotypes after the eradication of previous populations during extreme environmental conditions (high temperatures, UV irradiation, pH and salinity). The results indicate that, despite adverse chemical conditions, sedaDNA in tropical lake sediments is preserved for at least a few hundred years. Therefore, its analysis provides a useful complementary palaeoenvironmental proxy for palaeolimnological reconstructions and novel insights on changes in rotifer populations through time.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 49
    Publication Date: 2024-04-18
    Description: The Arctic Ocean is home to a unique fauna that is disproportionately affected by global warming but that remains under-studied. Due to their high mobility and responsiveness to global warming, cephalopods and fishes are good indicators of the reshuffling of Arctic communities. Here, we established a nekton biodiversity baseline for the Fram Strait, the only deep connection between the North Atlantic and Arctic Ocean. Using universal primers for fishes (12S) and cephalopods (18S), we amplified environmental DNA (eDNA) from seawater (50–2700 m) and deep-sea sediment samples collected at the LTER HAUSGARTEN observatory. We detected 12 cephalopod and 31 fish taxa in the seawater and seven cephalopod and 28 fish taxa in the sediment, including the elusive Greenland shark (Somniosus microcephalus). Our data suggest three fish (Mallotus villosus, Thunnus sp., and Micromesistius poutassou) and one squid (Histioteuthis sp.) range expansions. The detection of eDNA of pelagic origin in the sediment also suggests that M. villosus, Arctozenus risso, and M. poutassou as well as gonatid squids are potential contributors to the carbon flux. Continuous nekton monitoring is needed to understand the ecosystem impacts of rapid warming in the Arctic and eDNA proves to be a suitable tool for this endeavor.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 50
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Limnology and Oceanography, Wiley, 68(8), pp. 1880-1894, ISSN: 0024-3590
    Publication Date: 2024-03-01
    Description: The Southern Ocean, a globally important CO2 sink, is one of the most susceptible regions in the world to climate change. Phytoplankton of the coastal shelf waters around the Western Antarctic Peninsula have been experiencing rapid warming over the past decades and current ongoing climatic changes will expose them to ocean acidification and high light intensities due to increasing stratification. We conducted a multiple-stressor experiment to evaluate the response of the still poorly studied key Antarctic cryptophyte species Geminigera cryophila to warming in combination with ocean acidification and high irradiance. Based on the thermal growth response of G. cryophila, we grew the cryptophyte at suboptimal (2°C) and optimal (4°C) temperatures in combination with two light intensities (medium light: 100 μmol photons m−2 s−1 and high light [HL]: 500 μmol photons m−2 s−1) under ambient (400 μatm pCO2) and high pCO2 (1000 μatm pCO2) conditions. Our results reveal that G. cryophila was not susceptible to high pCO2, but was strongly affected by HL at 2°C, as both growth and carbon fixation were significantly reduced. In comparison, warming up to 4°C stimulated the growth of the cryptophyte and even alleviated the previously observed negative effects of HL at 2°C. When grown, however, at temperatures above 4°C, the cryptophyte already reached its maximal thermal limit at 8°C, pointing out its vulnerability toward even higher temperatures. Hence, our results clearly indicate that warming and high light and not pCO2 control the growth of G. cryophila.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 51
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Limnology and Oceanography, Wiley, 68(9), pp. 2153-2166, ISSN: 0024-3590
    Publication Date: 2024-03-01
    Description: Iron (Fe) and manganese (Mn) availability and the divergent requirements of phytoplankton species were recently shown to be potential important drivers of Southern Ocean community composition. Knowledge about Antarctic phytoplankton species requirements for Fe and Mn remains, however, scarce. By performing laboratory experiments and additional calculations of the photosynthetic electron transport, we investigated the response of the ecologically important species Phaeocystis antarctica under a combination of different Fe and Mn concentrations. Fe deprivation alone provoked typical physiological characteristics of Fe limitation in P. antarctica (e.g., lowered growth and photosynthetic efficiency). In comparison, under Mn deprivation alone, the growth and carbon production of P. antarctica were not impacted. Its tolerance to cope with low Mn concentrations resulted from an efficient photoacclimation strategy, including a higher number of active photosystems II through which fewer electrons were transported. This strategy allowed us to maintain similar high growth and carbon production rates as FeMn-enriched cells. Due to its low Mn requirement, P. antarctica performed physiologically as Fe-deprived cells under the combined depletion of Fe and Mn. Hence, our study reveals that different from other Southern Ocean phytoplankton species, P. antarctica possesses a high capacity to cope with natural low Mn concentrations, which can facilitate its dominance over others, potentially explaining its ecological success across the Southern Ocean.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 52
    Publication Date: 2024-02-22
    Description: The twisted-winged parasite genus Stylops has a history of different species concepts with varying host specificity resulting in diverse species diversity estimates in different regions of the Holarctic. The adoption of a supergeneralist species concept in Europe, proposing synonymization of all Western Palaearctic Stylops species, did not facilitate taxonomic clarity and obscured the available life-history data in the region for decades. Lack of molecular data has allowed divergent opinions on species hypotheses and little opportunity for evaluating them in this morphologically challenging genus. To solve these discrepancies and gain novel information about host associations, we applied whole-genome sequencing to 163 specimens, representing a significant portion of putative European species. We evaluate the existing and conflicting species hypotheses with molecular species delimitation using Species bOundry Delimitation using Astral (SODA)and use a maximum likelihood phylogeny to investigate host associations of the species. Furthermore, we evaluate the effect of a number of loci used in SODA for the number of inferred species. We find justification for synonymization of multiple species and indications of undescribed species, as well as new host\xe2\x80\x93parasite relationships. We show that the number of inferred species in SODA is exceedingly and positively correlated with the number of loci used, urging for cautious application. The results of our study bring clarity to the Western Palaearctic species diversity of Stylops. Furthermore, the comprehensive molecular dataset generated in this study will be a valuable resource for future studies on Stylops and the evolution of parasites in general.
    Keywords: [Released under the CC-BY NC 4.0 (\xe2\x80\x9cAttribution-NonCommercial 4.0 International\xe2\x80\x9d) ; License](https://creativecommons.org/licenses/by-nc/4.0/)
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 53
    Publication Date: 2024-04-16
    Description: A rapidly warming Arctic Ocean and associated sea-ice decline is resulting in changing sea-ice protist communities, affecting productivity of under-ice, pelagic, and benthic fauna. Quantifying such effects is hampered by a lack of biomarkers suitable for tracing specific basal resources (primary producers and microorganisms) through food webs. We investigate the potential of δ13C values of essential amino acids (EAAs) (δ13CEAA values) to estimate the proportional use of diverse basal resources by organisms from the under-ice (Apherusa glacialis), pelagic (Calanus hyperboreus) and benthic habitats (sponges, sea cucumber), and the cryo-pelagic fish Boreogadus saida. Two approaches were used: baseline δ13CEAA values, that is, the basal resource specific δ13CEAA values, and δ13CEAA fingerprints, or mean-centred baseline δ13CEAA values. Substantial use of sub-ice algae Melosira arctica by all studied organisms suggests that its role within Arctic food webs is greater than previously recognized. In addition, δ13CEAA fingerprints from algae-associated bacteria were clearly traced to the sponges, with an individually variable kelp use by sea cucumbers. Although mean-centred δ13CEAA values in A. glacialis, C. hyperboreus, and B. saida tissues were aligned with microalgae resources, they were not fully represented by the filtered pelagic- and sea-ice particulate organic matter constituting the spring diatom-dominated algal community. Under-ice and pelagic microalgae use could only be differentiated with baseline δ13CEAA values as similar microalgae clades occur in both habitats. We suggest that δ13CEAA fingerprints combined with microalgae baseline δ13CEAA values are an insightful tool to assess the effect of ongoing changes in Arctic basal resources on their use by organisms.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 54
    Publication Date: 2024-04-16
    Description: Color polymorphism is a classic study system for evolutionary genetics. One of the most color-polymorphic animal taxa is mollusks, but the investigation of the genetic basis of color determination is often hindered by their life history and the limited avail-ability of genetic resources. Here, we report on the discovery of shell color polymor-phism in a much-used model species, the great pond snail Lymnaea stagnalis. While their shell is usually beige, some individuals from a Greek population show a distinct red shell color, which we nicknamed Ginger. Moreover, we found that the inheritance fits simple, single-locus Mendelian inheritance with dominance of the Ginger allele. We also compared crucial life-history traits between Ginger and wild-type individuals, and found no differences between morphs. We conclude that the relative simplicity of this polymorphism will provide new opportunities for a deeper understanding of the genetic basis of shell color polymorphism and its evolutionary origin.
    Keywords: evolution ; genetics ; life history ; Mendelian inheritance ; simultaneous hermaphrodites
    Repository Name: National Museum of Natural History, Netherlands
    Type: info:eu-repo/semantics/article
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 55
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Journal of Phycology, Wiley, 59(5), pp. 799-808, ISSN: 0022-3646
    Publication Date: 2024-04-08
    Description: Dinoflagellates are a diverse group of eukaryotic microbes that are ubiquitous in aquatic environments. Largely photosynthetic, they encompass symbiotic, parasitic, and free-living lineages with a broad spectrum of trophism. Many free-living taxa can produce bioactive secondary metabolites such as biotox- ins, some of which cause harmful algal blooms. In contrast, most symbiotic species are crucial for sustaining coral reef health. The year 2023 marked a decade since the first genome data of dinoflagellates became available. The growing genome-scale resources for these taxa are highlighting their remarkable evolutionary and genomic complexities. Here, we discuss the prospect of developing dinoflagellate models using the criteria of accessibil- ity, tractability, resources, research support, and promise. Moving forward in the post-genomic era, we argue for the development of fit-to-purpose models that tailor to specific biological contexts, and that a one-size-fits-all model is inadequate for encapsulating the complex biology, ecology, and evolutionary history of dinoflagellates.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 56
    Publication Date: 2024-05-08
    Description: We analysed the robustness of species identification based on proteomic composition to data processing and intraspecific variability, specificity and sensitivity of species-markers as well as discriminatory power of proteomic fingerprinting and its sensitivity to phylogenetic distance. Our analysis is based on MALDI-TOF MS (matrix-assisted laser desorption ionization time of flight mass spectrometry) data from 32 marine copepod species coming from 13 regions (North and Central Atlantic and adjacent seas). A random forest (RF) model correctly classified all specimens to the species level with only small sensitivity to data processing, demonstrating the strong robustness of the method. Compounds with high specificity showed low sensitivity, that is identification was based on complex pattern-differences rather than on presence of single markers. Proteomic distance was not consistently related to phylogenetic distance. A species-gap in proteome composition appeared at 0.7 Euclidean distance when using only specimens from the same sample. When other regions or seasons were included, intraspecific variability increased, resulting in overlaps of intra and inter-specific distance. Highest intraspecific distances (〉0.7) were observed between specimens from brackish and marine habitats (i.e., salinity probably affects proteomic patterns). When testing library sensitivity of the RF model to regionality, strong misidentification was only detected between two congener pairs. Still, the choice of reference library may have an impact on identification of closely related species and should be tested before routine application. We envisage high relevance of this time- and cost-efficient method for future zooplankton monitoring as it provides not only in-depth taxonomic resolution for counted specimens but also add-on information, such as on developmental stage or environmental conditions.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , peerRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 57
    Publication Date: 2024-06-21
    Description: Nonvascular photoautotrophs (NVP), including bryophytes, lichens, terrestrial algae, and cyanobacteria, are increasingly recognized as being essential to ecosystem functioning in many regions of the world. Current research suggests that climate change may pose a substantial threat to NVP, but the extent to which this will affect the associated ecosystem functions and services is highly uncertain. Here, we propose a research agenda to address this urgent question, focusing on physiological and ecological processes that link NVP to ecosystem functions while also taking into account the substantial taxonomic diversity across multiple ecosystem types. Accordingly, we developed a new categorization scheme, based on microclimatic gradients, which simplifies the high physiological and morphological diversity of NVP and world-wide distribution with respect to several broad habitat types. We found that habitat-specific ecosystem functions of NVP will likely be substantially affected by climate change, and more quantitative process understanding is required on: (1) potential for acclimation; (2) response to elevated CO2; (3) role of the microbiome; and (4) feedback to (micro)climate. We suggest an integrative approach of innovative, multimethod laboratory and field experiments and ecophysiological modelling, for which sustained scientific collaboration on NVP research will be essential.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 58
    facet.materialart.
    Unknown
    Wiley
    In:  EPIC3Ecology and Evolution, Wiley, 13(10), pp. e10585-e10585, ISSN: 2045-7758
    Publication Date: 2024-06-21
    Description: Global climatic changes expected in the next centuries are likely to cause unparalleled vegetation disturbances, which in turn impact ecosystem services. To assess the significance of disturbances, it is necessary to characterize and understand typical natural vegetation variability on multi-decadal timescales and longer. We investigate this in the Holocene vegetation by examining a taxonomically harmonized and temporally standardized global fossil pollen dataset. Using principal component analysis, we characterize the variability in pollen assemblages, which are a proxy for vegetation composition, and derive timescale-dependent estimates of variability using the first-order Haar structure function. We find, on average, increasing fluctuations in vegetation composition from centennial to millennial timescales, as well as spatially coherent patterns of variability. We further relate these variations to pairwise comparisons between biome classes based on vegetation composition. As such, higher variability is identified for open-land vegetation compared to forests. This is consistent with the more active fire regimes of open-land biomes fostering variability. Needleleaf forests are more variable than broadleaf forests on shorter (centennial) timescales, but the inverse is true on longer (millennial) timescales. This inversion could also be explained by the fire characteristics of the biomes as fire disturbances would increase vegetation variability on shorter timescales, but stabilize vegetation composition on longer timecales by preventing the migration of less fire-adapted species.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 59
    Publication Date: 2024-06-18
    Description: The study of environmental ancient DNA provides us with the unique opportunity to link environmental with ecosystem change over a millennial timescale. Paleorecords such as lake sediments contain genetic pools of past living organisms that are a valuable source of information to reconstruct how ecosystems were and how they changed in response to climate in the past. Here, we report on paleometagenomics of a sedimentary record in northern Siberia covering the past 6700 years. We integrated taxonomic with functional gene analysis, which enabled to shed light not only on community compositions but also on eco-physiological adaptations and ecosystem functioning. We reconstructed the presence of an open boreal forest 6700 years ago that over time was gradually replaced by tundra. This vegetation change had major consequences on the environmental microbiome, primarily enriching bacterial and archaeal ammonia oxidizers (e.g., Nitrospira, Nitrosopumilus, and Ca. Nitrosocosmicus) in the tundra ecosystem. We identified a core microbiome conserved through time and largely consisting of heterotrophic bacteria of the Bacteroidetes phylum (e.g., Mucilaginibacter) harboring numerous functional genes for degradation of plant-biomass and abiotic and biotic stress resistance. Archaea were also a key functional guild, involved in nitrogen and carbon cycling, not only methanogenesis but possibly also degradation of plant material via enzymes such as cellulases and amylases. Overall, the paleo-perspective offered by our study can have a profound impact on modern climate change biology, by helping to explain and predict the ecological interplay among multiple ecosystem levels based on past experiences.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 60
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] TPA, an activator of protein kinase C, triggers platelet aggregation as well as the secretion of [14C]-serotonin from platelets11-13. The response to activation by 1 mM TPA at 37 C, with constant stirring, is more gradual than the response to activation by O.1Uml-1 thrombin and maximal aggregation ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 61
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 503-503 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] GASKELL REPLIES-While recognizing that the main point of Jordan's comment is to attempt to correct the allegedly misleading generalizations made by Fair all1 and myself2, I must state that the size of the forbidden line emitting region in Fairall 427 is not an open question. If one looks at ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 62
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 731-731 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE article on page 756 from Dr P. W. J. Rigby's group at Imperial College is an intriguing document which is plainly of the utmost importance, but for reasons which, at this stage, are not fully apparent. The obvious difficulty is that the observations described bear on such a variety of important ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 63
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 727-730 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] WRITING some thirty years ago, Hermann Bondi suggested that in astronomy, observations had proven a less reliable arbiter of hypotheses than had theoretical considerations1 . Subsequent historical studies have widened and deepened knowledge of some of the instances cited by Bondi and have uncovered ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 64
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 733-736 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE cellular myc gene may, depending on your point of view, be seen as either the most illuminating or the most confusing of the cellular oncogenes. The promise of illumination lies in the overwhelming circumstantial evidence that c-myc activation in some lymphoid tumours is a direct subversion, ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 65
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 737-738 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] AFTER some years of increasing interest, rapid progress is now being made in the understanding of lignin biodegradation. Research in a number of laboratories has culminated in the isolation by T.K. Kirk and Ming Tien of a purified enzyme able to depolymerize lignin1. This enzyme, isolated from the ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 66
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 739-740 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] ALTHOUGH an ever-increasing number of pharmacologically active peptides are being found in neurones of the central nervous system, it is still not proving possible to find out precisely what neuro-transmitter or neuromodulator functions they perform. This may not be so surprising when one remembers ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 67
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 741-741 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] IN a letter dated Tokio, October 3, Prof. James Main Dixon writes:- "During the two or three days at the end of August we enjoyed fine dry weather, but the sun was copper-coloured and had no brightness. When we got to Nikko, the people came to us to inquire if some catastrophe were impending, for ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 68
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 742-742 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] CAIRNS AND LOGAN REPLY - In the first half of his letter, Dr Holliday gives three reasons for thinking that programmed cell senescence is not a protection against the development of cancer. We believe that each of the arguments is fallacious. The common human cancers, as described in textbooks of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 69
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 743-746 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The date of the Crucifixion has been debated for many years, but there has been no agreement on the year nor the day. Astronomical calculations have now been used to reconstruct the Jewish calendar in the first century AD and to date a lunar eclipse that biblical and other references ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 70
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 747-751 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Tropospheric ions are of considerable interest as they have the potential to induce aerosol formation and because in situ measurements of their composition are a powerful tool for neutral trace gas detection. The first measurements of tropospheric ion compositions are now ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 71
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] A cDNA clone corresponding to a mRNA present at elevated levels in transformed fibroblasts encodes a Qa / Tla class I major histocompatibility complex (MHC) antigen. High levels of this mRNA are found in all tumour cells tested; the transcript can undergo alternative splicing; and a repetitive ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 72
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 765-766 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Our model of photon oscillations is a simple extension of the standard gauge theory of strong interactions wherein an additional gauged U'(l) factor is adjoined to the usual spontaneously broken SU(3) xSU(2) xU(1). Known particles transform trivially under U'(1). At this point, the model involves ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 73
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 768-770 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Graphitic particles can only be produced by combustion processes. If one excludes natural burning processes that are not expected to be a significant source during winter and spring when Arctic haze is at a maximum, then one can attribute these particles directly to anthropogenic combustion ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 74
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 772-773 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] More than half a century ago it was postulated that coal was a 'polymeric' or macromolecular substance1-3. However, the evidence has not been completely convincing, and the particular nature of the macromolecular state has remained uncertain. Boddy4 found that coals, which normally exhibit brittle ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 75
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 662-666 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The β-globin gene present on the deletion locus in a Dutch γβ-thalassaemic patient was found to be identical to the normal β-globin gene with respect to DNA sequence and its transcription in HeLa cells. DNase I sensitivity and methylation experiments show that the affected ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 76
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 670-673 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The lines in the spectrum of the Zurich sunspot index in the interval 100 〈 t 〈 8 yr (where t is the period) match those of a model in which a 22-yr carrier 'wave' representing the Hale 22-yr cycle is amplitude modulated (AM) at the 90 yr (Gleissburg) period in the presence of a small but ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 77
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 676-677 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] An observed deficiency of chloride ions in coastal aerosols in some locations has been attributed to a reaction of HNO3 or NO2 with NaCl (refs 7-12). Gaseous HC1 has been assumed to be the product based on studies11,12 showing that 0.1-100 p.p.m. NO2 reacted rapidly with moist NaCl aerosols to ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 78
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 679-680 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The anorthosites were emplaced into presumed Archaean quartzof eldspathic gneisses, although in large areas of the Grenville Province, both massifs and basement rocks were reworked during late Proterozoic (about 1,000 Myr) Grenvillian metamorphism5. The Adirondack anorthosite may have crystallized ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 79
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The basicranium is part of a dorsoventrally crushed skull and upper dentition of Diacodon alticuspis, an erinaceomorph from the Lower Eocene (Wasatchian North American Land Mammal Age, about 52 Myr BP) of northern New Mexico7. The specimen was collected in 1946 by an American Museum of Natural ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 80
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 688-691 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Indirect immunofluorescence techniques were used to identify the cholinergic and substance P-containing neurones of the midbrain and pontine tegmentum of young adult male rats (150-200 g, Wistar). To increase the levels of ChAT and substance P in cell bodies, the animals were given an injection of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 81
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] There is considerable evidence that the major immunogen is situated on VP1, one of the four capsid proteins1-5. Furthermore, the position of the major immunogenic site on VP1 of virus of serotype 0 has been shown to lie within the amino acid tract 141-1606-8. The same region of VP1 from other ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 82
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The Thy-1 glycoprotein exists in two allotypic forms, Thy 1.1 and Thy 1.2 (ref. 4). It has been proposed that an arginine residue at position 89 corresponds to the Thy 1.1 allotype and a glutamine residue to Thy 1.2 (ref. 5). Since the two proteins differ by only a single residue, they offered a ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 83
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 699-701 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Trypanosoma brucei rhodesiense, causative agent of East African sleeping sickness in man, also infects domestic and game animals. As the sole criterion for distinguishing T. b. rhodesiense from T. b. brucei is the former's infectivity to man, any T. brucei group stock isolated from reservoir host ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 84
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 704-707 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Previously we have isolated two recombinant plasmids (pYA102 and pYA208) containing overlapping DNA fragments which harbour the yeast actin gene8,9. In studying the region 5' to the actin gene we detected another gene whose transcription product is a polysomal RNA coding for a protein of 20,000 ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 85
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 707-709 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] The transforming genes of Harvey and Kirsten murine sarcoma viruses have been named ras oncogenes because these two oncogenic retroviruses were originally isolated by passage of murine leukaemia viruses in rats1. The ras oncogene of Harvey murine sarcoma virus has been named v-rasH and that of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 86
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 709-712 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] We have previously shown that linker histone (H1 and H5) induced chromatin condensation, as measured by electron microscopy, is directly proportional to the sedimentation rate5. Here we have used the sedimentation rate of chromatin as the primary measure of its higher order folding. Our ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 87
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 713-714 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THIS is the book we have been waiting for. Fifteen years ago, the neutral theory was proposed by Kimura, and independently by King and Jukes. In Kimura's formulation, it made two assertions. First, chance events have been more important than natural selection in bringing about evolutionary changes ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 88
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 714-714 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE realization in the early 1970s that free radicals are a normal component of the Earth's lower atmosphere revolutionized our understanding of atmospheric chemistry and its role in the larger biogeo-chemical cycling of the elements. However, the advances made in this field over the past decade ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 89
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 714-715 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] As most historians portray it, science is a linear sequence of triumphant discoveries. Occasionally we hear of scientists who were mistaken, just so long as they were mistaken in big ways. But most scientists fail in the most literal sense of this term. They may publish a few papers, but these ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 90
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 715-715 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] GLIMPSE of 1986 - an artist's impression of the International Solar Polar Mission spacecraft (which is now completed) atop a Centaur upper stage after its deployment from the Space Shuttle. The illustration is taken from a new publication of the European Space Agency, The International Solar Polar ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 91
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 521-521 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] How, in the long run, can a modern state hope to deal equitably with its pensioners, especially if a substantial fraction of its putatively working population is forced into premature pensionhood by unemployment? And what if the social burden of the unemployment rolls will in any case be made ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 92
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 522-522 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] ROBERT Nozick, the Harvard University philosopher, wrote last week in the New York Times that animal rights is a subject that seems to attract cranks. The distinguishing feature of a crank, he was quick to point out, is not merely preoccupation with a single issue; the solving of the world's ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 93
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 522-522 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] How would you find out whether a ball that bounces best on one surface bounces best on all surfaces? How would you tell why a snail will not cross a ring of salty water? These are some of the questions that have been put to 11-year-olds in British primary schools by a group of investigators from ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 94
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 523-523 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE Agricultural and Food Research Council (AFRC) has now completed its strategic plan, intended as an adaptation to the expected substantial drop in its share of the science budget over the next few years. The plan, which has not yet been ratified, will be discussed next week at a meeting of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 95
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 523-523 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] NATURE is able today to report the exciting news that there is life - of a kind - in outer space. Through the marvels of modern communications, President Ronald Reagan, Chancellor Helmut Kohl of West Germany, your correspondent and a few other European journalists were able on Monday to direct ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 96
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 524-524 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE Linus Pauling Institute of Science and Medicine in Palo Alto, California, has settled yet another lawsuit brought by a former employee who claimed to have been dismissed from a tenured research position. Dr Fred West all, who worked at the institute in 1978 and 1979, had accused Pauling of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 97
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 524-524 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Chicago UNDAUNTED by 12 years of intermittent controversy, distinguished academics continue to flock to the annual conference on "the unity of the sciences" sponsored by Reverend Sun Myung Moon's Unification Church. This year's conference, held here last week, heard the Nobel economist F.A. Hayek ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 98
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 525-525 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THE Wildlife and Countryside Act, introduced two years ago, has run into serious trouble. British conservation groups are complaining that the act fails to provide adequate protection to places designated by the Nature Conservancy Council (NCC) as Sites of Special Scientific Interest (SSSIs). The ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 99
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 525-525 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] FINLAND is planning a massive modification of its environmental legislation over the next ten years. At present, the laws of environmental protection are a confused collection of ad hoc acts introduced piecemeal to cope with specific problems. The need for a legislative review was underlined by the ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 100
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 306 (1983), S. 526-526 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] OUT of the political and economic gloom over the Athens summit earlier this week, where European Prime Ministers were attempting to thrash out a solution to the European Community's burgeoning "budget problem", officials were hoping for a little "green light" for biotechnology. The heads of ...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...