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Author Alain Manceau, Romain Brossier, Sarah E. Janssen, Tylor J. Rosera, David P. Krabbenhoft, Yves Cherel, Paco Bustamante, Brett A. Poulin doi  openurl
  Title (up) Mercury Isotope Fractionation by Internal Demethylation and Biomineralization Reactions in Seabirds: Implications for Environmental Mercury Science Type Journal
  Year 2021 Publication Environmental Science & Technology Abbreviated Journal  
  Volume 55 Issue 20 Pages 13942-13952  
  Keywords  
  Abstract A prerequisite for environmental and toxicological applications of mercury (Hg) stable isotopes in wildlife and humans is quantifying the isotopic fractionation of biological reactions. Here, we measured stable Hg isotope values of relevant tissues of giant petrels (Macronectes spp.). Isotopic data were interpreted with published HR-XANES spectroscopic data that document a stepwise transformation of methylmercury (MeHg) to Hg-tetraselenolate (Hg(Sec)4) and mercury selenide (HgSe) (Sec = selenocysteine). By mathematical inversion of isotopic and spectroscopic data, identical δ202Hg values for MeHg (2.69 ± 0.04‰), Hg(Sec)4 (−1.37 ± 0.06‰), and HgSe (0.18 ± 0.02‰) were determined in 23 tissues of eight birds from the Kerguelen Islands and Adélie Land (Antarctica). Isotopic differences in δ202Hg between MeHg and Hg(Sec)4 (−4.1 ± 0.1‰) reflect mass-dependent fractionation from a kinetic isotope effect due to the MeHg → Hg(Sec)4 demethylation reaction. Surprisingly, Hg(Sec)4 and HgSe differed isotopically in δ202Hg (+1.6 ± 0.1‰) and mass-independent anomalies (i.e., changes in Δ199Hg of ≤0.3‰), consistent with equilibrium isotope effects of mass-dependent and nuclear volume fractionation from Hg(Sec)4 → HgSe biomineralization. The invariance of species-specific δ202Hg values across tissues and individual birds reflects the kinetic lability of Hg-ligand bonds and tissue-specific redistribution of MeHg and inorganic Hg, likely as Hg(Sec)4. These observations provide fundamental information necessary to improve the interpretation of stable Hg isotope data and provoke a revisitation of processes governing isotopic fractionation in biota and toxicological risk assessment in wildlife.  
  Programme 109  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0013-936X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8427  
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Author Marina Renedo, Zoyne Pedrero, David Amouroux, Yves Cherel, Paco Bustamante doi  openurl
  Title (up) Mercury isotopes of key tissues document mercury metabolic processes in seabirds Type Journal
  Year 2021 Publication Chemosphere Abbreviated Journal  
  Volume 263 Issue Pages 127777  
  Keywords Demethylation Detoxification Metabolism Methylmercury Moult  
  Abstract Seabirds accumulate significant amounts of mercury (Hg) due to their long-life span together with their medium to high trophic position in marine food webs. Hg speciation and Hg isotopic analyses of total Hg in different tissues (pectoral muscles, liver, brain, kidneys, blood and feathers) were assessed to investigate their detoxification mechanisms. Three species with contrasted ecological characteristics were studied: the Antarctic prion (zooplankton feeder), the white-chinned petrel (pelagic generalist consumer) and the southern giant petrel (scavenger on seabirds and marine mammals). The difference of mass-dependent fractionation (MDF, δ202Hg) values between liver and muscles (up to 0.94 ‰) in all three seabirds strongly suggests hepatic demethylation of the isotopically lighter methylmercury (MeHg) and subsequent redistribution of the isotopically heavier fraction of MeHg towards the muscles. Similarly, higher δ202Hg values in feathers (up to 1.88 ‰) relative to muscles and higher proportion of MeHg in feathers (94–97%) than muscles (30–70%) likely indicate potential MeHg demethylation in muscle and preferential excretion of MeHg (isotopically heavier) in the growing feathers during moult. The extents of these key detoxification processes were strongly dependent on the species-specific detoxification strategies and levels of dietary MeHg exposure. We also found higher mass-independent fractionation (MIF, Δ199Hg) values in feathers relative to internal tissues, possibly due to different integration times of Hg exposure between permanently active organs and inert tissues as feathers. Hg isotope variations reported in this study show evidence of detoxification processes in seabirds and propose a powerful approach for deep investigation of the Hg metabolic processes in seabirds.  
  Programme 109  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0045-6535 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8084  
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Author Petra Zemunik, Jadranka Šepić, Havu Pellikka, Leon Ćatipović, Ivica Vilibić doi  openurl
  Title (up) Minute Sea-Level Analysis (MISELA): a high-frequency sea-level analysis global dataset Type Journal
  Year 2021 Publication Earth system science data Abbreviated Journal  
  Volume 13 Issue 8 Pages 4121-4132  
  Keywords  
  Abstract

Abstract. Sea-level observations provide information on a variety of processes occurring over different temporal and spatial scales that may contribute to coastal flooding and hazards. However, global research on sea-level extremes is restricted to hourly datasets, which prevent the quantification and analyses of processes occurring at timescales between a few minutes and a few hours. These shorter-period processes, like seiches, meteotsunamis, infragravity and coastal waves, may even dominate in low tidal basins. Therefore, a new global 1 min sea-level dataset – MISELA (Minute Sea-Level Analysis) – has been developed, encompassing quality-checked records of nonseismic sea-level oscillations at tsunami timescales (T<2 h) obtained from 331 tide-gauge sites (https://doi.org/10.14284/456, Zemunik et al., 2021b). This paper describes data quality control procedures applied to the MISELA dataset, world and regional coverage of tide-gauge sites, and lengths of time series. The dataset is appropriate for global, regional or local research of atmospherically induced high-frequency sea-level oscillations, which should be included in the overall sea-level extremes assessments.

 
  Programme 688  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1866-3508 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8392  
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Author Danish A. Ahmed, Emma J. Hudgins, Ross N. Cuthbert, Phillip J. Haubrock, David Renault, Elsa Bonnaud, Christophe Diagne, Franck Courchamp doi  openurl
  Title (up) Modelling the damage costs of invasive alien species Type Journal
  Year 2021 Publication Biological Invasions Abbreviated Journal  
  Volume Issue Pages  
  Keywords  
  Abstract The rate of biological invasions is growing unprecedentedly, threatening ecological and socioeconomic systems worldwide. Quantitative understandings of invasion temporal trajectories are essential to discern current and future economic impacts of invaders, and then to inform future management strategies. Here, we examine the temporal trends of cumulative invasion costs by developing and testing a novel mathematical model with a population dynamical approach based on logistic growth. This model characterises temporal cost developments into four curve types (I–IV), each with distinct mathematical and qualitative properties, allowing for the parameterization of maximum cumulative costs, carrying capacities and growth rates. We test our model using damage cost data for eight genera (Rattus, Aedes, Canis, Oryctolagus, Sturnus, Ceratitis, Sus and Lymantria) extracted from the InvaCost database—which is the most up-to-date and comprehensive global compilation of economic cost estimates associated with invasive alien species. We find fundamental differences in the temporal dynamics of damage costs among genera, indicating they depend on invasion duration, species ecology and impacted sectors of economic activity. The fitted cost curves indicate a lack of broadscale support for saturation between invader density and impact, including for Canis, Oryctolagus and Lymantria, whereby costs continue to increase with no sign of saturation. For other taxa, predicted saturations may arise from data availability issues resulting from an underreporting of costs in many invaded regions. Overall, this population dynamical approach can produce cost trajectories for additional existing and emerging species, and can estimate the ecological parameters governing the linkage between population dynamics and cost dynamics.  
  Programme 136  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1573-1464 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8090  
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Author Charlène Guillaumot file  openurl
  Title (up) Modelling the response of Antarctic marine species to environmental changes. Methods, applications and limitations. /// Modéliser la réponse des espèces marines antarctiques aux changements environnementaux. Méthodes, applications et limites. Type Thesis
  Year 2021 Publication Thèse de doctorat. université libre de bruxelles / université de bourgogne franche-comté Abbreviated Journal  
  Volume Issue Pages 620 pp.  
  Keywords  
  Abstract Parmi les outils qui permettent de mieux comprendre les systèmes naturels, la modélisation écologique a connu un essor particulièrement important depuis une vingtaine d’années. Les modèles écologiques, représentation simplifiée d’une réalité complexe, permettent de mettre en avant les facteurs environnementaux qui déterminent la niche écologique des espèces et de mieux comprendre leur réponse aux changements de l’environnement. Dans le cas des faunes marines antarctiques, la modélisation écologique fait face à plusieurs défis méthodologiques. Les jeux de données de présence des espèces sont très souvent agrégés dans le temps et dans l’espace, à proximité des stations de recherche. Ces données sont souvent trop peu nombreuses pour caractériser l’espace environnemental occupé par les espèces ainsi que leur physiologie. Enfin, les jeux de données environnementales manquent encore de précision pour finement représenter la complexité des habitats marins. Dans ces conditions, est-il possible de générer des modèles performants et justes à l’échelle de l’océan Austral ? Quelles sont les approches possibles et leurs limites ? Comment améliorer les méthodes afin de générer de meilleurs modèles ? Au cours de ce travail de thèse, trois types de modèles ont été étudiés et leurs performances évaluées. (1) Les modèles physiologiques de type DEB (Dynamic Energy Budget) simulent la manière dont l’environnement abiotique influe sur le métabolisme des individus et proposent une représentation de la niche fondamentale des espèces. (2) Les modèles de distribution d’espèces (SDMs pour Species Distribution Models) prédisent la probabilité de distribution des espèces en étudiant la relation spatiale entre données de présence et environnement. Ils proposent une représentation de la niche réalisée des espèces. Enfin (3), les modèles de dispersion de type lagrangien prédisent le mouvement de propagules dans les masses d’eau. Les résultats montrent que les modèles physiologiques réussissent à simuler les variations métaboliques des espèces antarctiques en fonction de l’environnement et à prédire les dynamiques de populations. Cependant, davantage de données sont nécessaires pour pouvoir caractériser finement les différences physiologiques entre populations et évaluer correctement les modèles. Les résultats obtenus pour les SDMs montrent que les modèles générés à l’échelle de l’océan Austral et leurs prédictions futures ne sont pas fiables du fait du manque de données disponibles pour caractériser l’espace occupé par les espèces, du manque de précision des scénarios climatiques futurs et de l’impossibilité d’évaluer les modèles. De plus, les modèles extrapolent sur une très grande proportion de l’espace projeté. L’apport d’information complémentaire sur les limites physiologiques des espèces (observations, résultats d’expériences, sorties de modèles physiologiques) permet de réduire l’extrapolation et d’augmenter la capacité des modèles à décrire la niche réalisée des espèces. L’agrégation spatiale des données, qui influençait les prédictions et l’évaluation des modèles a également pu être corrigée. Enfin, les modèles de dispersion ont montré un potentiel intéressant pour révéler le rôle des barrières géographiques ou à l’inverse, la connectivité spatiale, mais également le lien existant entre distribution, physiologie et histoire phylogénétique des espèces. Ce travail de thèse propose de nombreux conseils et fournit des codes annotés parfois sous forme de tutoriels, afin de constituer une aide utile aux futurs travaux de modélisation sur les espèces marines antarctiques.  
  Programme 688,1044  
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  Corporate Author Thesis Bachelor's thesis  
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  Notes Approved yes  
  Call Number Serial 6439  
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Author F. Bultelle, I. Boutet, S. Devin, F. Caza, Y. St-Pierre, R. Péden, P. Brousseau, P. Chan, D. Vaudry, F. Le Foll, M. Fournier, M. Auffret, B. Rocher doi  openurl
  Title (up) Molecular response of a sub-antarctic population of the blue mussel (Mytilus edulis platensis) to a moderate thermal stress Type Journal
  Year 2021 Publication Marine Environmental Research Abbreviated Journal  
  Volume 169 Issue Pages 105393  
  Keywords 2DE Abiotic stress Biomonitoring Gills Indicator species Kerguelen island Mytilus sp. qRT-PCR Temperature  
  Abstract The Kerguelen Islands (49°26′S, 69°50′E) represent a unique environment due to their geographical isolation, which protects them from anthropogenic pollution. The ability of the endemic mussel, part of the Mytilus complex, to cope with moderate heat stress was explored using omic tools. Transcripts involved in six major metabolic functions were selected and the qRT-PCR data indicated mainly changes in aerobic and anaerobic energy metabolism and stress response. Proteomic comparisons revealed a typical stress response pattern with cytoskeleton modifications and elements suggesting increased energy metabolism. Results also suggest conservation of protein homeostasis by the long-lasting presence of HSP while a general decrease in transcription is observed. The overall findings are consistent with an adaptive response to moderate stresses in mussels in good physiological condition, i.e. living in a low-impact site, and with the literature concerning this model species. Therefore, local blue mussels could be advantageously integrated into biomonitoring strategies, especially in the context of Global Change.  
  Programme 409  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0141-1136 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8256  
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Author Crouzet N. openurl 
  Title (up) Monitoring warm transiting exoplanets for Ariel with ASTEP+ Type Communication
  Year 2021 Publication Journée Ariel France, 28 janvier 2021 Abbreviated Journal  
  Volume Issue Pages  
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  Programme 1066  
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  Notes Approved yes  
  Call Number Serial 7826  
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Author Barbora Chattová, Marc Lebouvier, Vít Syrovátka, Bart Van de Vijver doi  openurl
  Title (up) Moss-inhabiting diatom communities from Ile Amsterdam (TAAF, southern Indian Ocean) Type Journal
  Year 2021 Publication Plant Ecology and Evolution Abbreviated Journal  
  Volume 154 Issue 1 Pages 63-79  
  Keywords Bacillariophyta diatoms ecology Ile Amsterdam mosses southern Indian Ocean sub-Antarctic region  
  Abstract Background and aims – Despite the ongoing taxonomical revision of the entire (sub)-Antarctic diatom flora, our knowledge on the ecology and community associations of moss-inhabiting diatoms is still rather limited. In the present study, our research aim was to survey the diversity together with the environmental factors structuring the epiphytic moss diatom communities on Ile Amsterdam (TAAF), a small volcanic island in the southern Indian Ocean.Material and methods – A morphology-based dataset and (physico)chemical measurements were used for the ecological and biogeographical analysis of moss-inhabiting diatom flora from Ile Amsterdam. In total, 148 moss samples were examined using light microscopy.Key results – The analysis revealed the presence of 125 diatom taxa belonging to 38 genera. The uniqueness of the Ile Amsterdam diatom flora is mainly reflected by the species composition of the dominant genera Pinnularia, Nitzschia, Humidophila, and Luticola, with a large number of unknown and often new species. This highly specific diatom flora, together with differences in the habitats sampled and the isolated position of the island, resulted in very low similarity values between Ile Amsterdam and the other islands of the Southern Ocean. From a biogeographical point of view, 40% of the taxa have a typical cosmopolitan distribution, whereas 22% of all observed species can be considered endemic to Ile Amsterdam, with another 17% species showing a restricted sub-Antarctic distribution. The NMDS analysis, based on a cluster dendrogram, divides the samples into six main groups. For each group, indicator species were determined. Both environmental data and diatom distributions indicate that apart from elevation, specific conductance, pH, and moisture are the major factors determining the structure of moss-inhabiting diatom communities on Ile Amsterdam.Conclusion – The isolated geographic position and unique climatological and geological features of the island shaped the presence of a unique diatom flora, characterised by many endemic species. The results of the study are of prime importance for further (palaeo-)ecological and biogeographical research.  
  Programme 136  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 2032-3921 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7974  
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Author L A Ermert, K Sager, T Nissen-Meyer, A Fichtner doi  openurl
  Title (up) Multifrequency inversion of global ambient seismic sources Type Journal
  Year 2021 Publication Geophysical Journal International Abbreviated Journal  
  Volume 225 Issue 3 Pages 1616-1623  
  Keywords  
  Abstract We develop and apply a method to constrain the space- and frequency-dependent location of ambient noise sources. This is based on ambient noise cross-correlation inversion using numerical wavefield simulations, which honour 3-D crustal and mantle structure, ocean loading and finite-frequency effects. In the frequency range from 3 to 20 mHz, our results constrain the global source distribution of the Earth’s hum, averaged over the Southern Hemisphere winter season of 9 yr. During Southern Hemisphere winter, the dominant sources are largely confined to the Southern Hemisphere, the most prominent exception being the Izu-Bonin-Mariana arc, which is the most active source region between 12 and 20 mHz. Generally, strong hum sources seem to be associated with either coastlines or bathymetric highs. In contrast, deep ocean basins are devoid of hum sources. While being based on the relatively small number of STS-1 broad-band stations that have been recording continuously from 2004 to 2013, our results demonstrate the practical feasibility of a frequency-dependent noise source inversion that accounts for the complexities of 3-D wave propagation. It may thereby improve full-waveform ambient noise inversions and our understanding of the physics of noise generation.  
  Programme 133  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0956-540X ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 7992  
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Author Maud Quéroué, Christophe Barbraud, Frédéric Barraquand, Daniel Turek, Karine Delord, Nathan Pacoureau, Olivier Gimenez file  doi
openurl 
  Title (up) Multispecies integrated population model reveals bottom-up dynamics in a seabird predator–prey system Type Journal
  Year 2021 Publication Ecological Monographs Abbreviated Journal  
  Volume 91 Issue 3 Pages e01459  
  Keywords Bayesian inference demography environmental variation integrated population model matrix population model Nimble predator–prey interactions  
  Abstract Assessing the effects of climate and interspecific relationships on communities is challenging because of the complex interplay between species population dynamics, their interactions, and the need to integrate information across several biological levels (individuals, populations, communities). Usually used to quantify single-species demography, integrated population models (IPMs) have recently been extended to communities. These models allow fitting multispecies matrix models to data from multiple sources while simultaneously accounting for uncertainty in each data source. We used multispecies IPMs accommodating climatic variables to quantify the relative contribution of climate vs. interspecific interactions on demographic parameters, such as survival and breeding success, in the dynamics of a predator–prey system. We considered a stage-structured predator–prey system combining 22 yr of capture–recapture data and population counts of two seabirds, the Brown Skua (Catharacta lönnbergi) and its main prey the Blue Petrel (Halobaena caerulea), both breeding on the Kerguelen Islands in the Southern Ocean. Our results showed that climate and predator–prey interactions drive the demography of skuas and petrels in different ways. The breeding success of skuas appeared to be largely driven by the number of petrels and to a lesser extent by intraspecific density dependence. In contrast, there was no evidence of predation effects on the demographic parameters of petrels, which were affected by oceanographic factors. We conclude that bottom-up mechanisms are the main drivers of this skua–petrel system.  
  Programme 109  
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  Corporate Author Thesis Bachelor's thesis  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1557-7015 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8210  
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