Annabel Rixen, Sylvie Blangy. (2016). (Vol. 3).
Keywords: Caribou livelihoods Future scenarios Inuit well-being Mine closure Participatory action research Remediation
Programme: 1193
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Karine Delord, Christophe Barbraud, David Pinaud, Stephanie Ruault, Samantha C. Patrick, Henri Weimerskirch. (2019). Individual consistency in the non-breeding behavior of a long-distance migrant seabird, the Grey Petrel Procellaria cinerea (Vol. 47).
Abstract: There is growing interest in the consistency of individual differences in animal behavior as it relates to life history traits and fitness. Despite the relatively large number of studies investigating repeatable behaviors, studies have only recently investigated repeatability in foraging or migratory behaviors, and this has seldom been explored between years. We examined the individual consistency in foraging behavior of the Grey Petrel Procellaria cinerea, a pelagic long-distance migrant seabird. We analyzed how foraging, activity, and migratory patterns were repeatable across different seasons. We used tracking data to monitor the migratory movements and behavior of individuals during the non-breeding period over five years. Despite the small sample size, we found that there was a relatively high individual consistency in wintering strategies across years, with birds displaying high fidelity to their non-breeding destinations during consecutive years. Activity parameters, date of departure of inward migration, duration of migration, and duration spent in non-breeding areas were repeatable as well. The duration of the non-breeding period was the most repeatable, reflecting consistent departure times and, to a lesser extent, consistent arrival times. A high overall repeatability was seen in the timing of return migration. With respect to sex, males tended to be more consistent in their migration strategy (i.e., timing of migration, time spent in non-breeding areas) than females. Although conditions during the Holocene have generally been stable in the Southern Ocean, species lacking variability in migratory traits are probably at a considerable disadvantage in terms of their capacity to respond to the rapid environmental changes currently underway.
Programme: 109
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. (2014). (Vol. 27).
Keywords: Arctic Glacier limit Ground penetrating Radar Polar glacier Spitsbergen
Programme: 1108
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T. Shirai, M. Ishizawa, R. Zhuravlev, A. Ganshin, D. Belikov, M. Saito, T. Oda, V. Valsala, A. J. Gomez-Pelaez, R. Langenfelds, S. Maksyutov. (2017). (Vol. 69).
Keywords: carbon cycle carbon dioxide coupled model flux estimation inversion top-down approach tropical Asia
Programme: 416
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. (2019). Abiotic degradation of highly branched isoprenoid alkenes and other lipids in the water column off East Antarctica (Vol. 210).
Abstract: In some previous studies, the ratio between a di-unsaturated highly branched isoprenoid (HBI) lipid termed IPSO25 and a structurally related tri-unsaturated counterpart (HBI III) (viz. IPSO25/HBI III) has been used as a proxy measure of variable sea ice cover in the Antarctic owing to their production by certain sea ice algae and open water diatoms, respectively. To investigate this further, we quantified selected lipids and their photo- and autoxidation products in samples of suspended particulate matter (SPM) collected at different water depths in the polynya region west of the Dalton Iceberg Tongue (East Antarctica). The results obtained confirm the high efficiency of photo- and autoxidation processes in diatoms from the region. The systematic increase of the ratio IPSO25/HBI III with water depth in the current samples appeared to be dependent on the sampling site and was due to both (i) a relatively higher contribution of ice algae to the deeper samples resulting from their increased aggregation and therefore higher sinking rate, or (ii) a stronger abiotic degradation of HBI III during settling through the water column. Analyses of samples taken from the water-sediment interface and some underlying near-surface sediments revealed a further increase of the ratio IPSO25/HBI III, indicative of further differential oxidation of the more unsaturated HBI. Unfortunately, specific oxidation products of HBI III could not be detected in the strongly oxidized SPM and sediment samples, likely due to their lability towards further oxidation. In contrast, oxidation products of HBI III were detected in weakly oxidized samples of phytoplanktonic cells collected from Commonwealth Bay (also East Antarctica), thus providing more direct evidence for the involvement of photo- and/or autoxidation of HBI III in the region. This oxidative alteration of the ratio IPSO25/HBI III between their source and sedimentary environments might need to be considered more carefully when using this parameter for palaeo sea ice reconstruction purposes in the Antarctic.
Keywords: Alteration of IPSO/HBI III ratio East Antarctica Lipids Near-surface sediments Paleoceanographic implications Photo- and autoxidation Suspended particulate matter
Programme: 1010
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. (2019). Individual variability in contaminants and physiological status in a resident Arctic seabird species (Vol. 249).
Keywords: Black guillemot Oxidative stress Polar regions Pollutants Seabirds Telomeres
Programme: 137
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. (2016). Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds (Vol. 4).
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. (2021). Exploring the Microdiversity Within Marine Bacterial Taxa: Toward an Integrated Biogeography in the Southern Ocean (Vol. 12).
Abstract: Most of the microbial biogeographic patterns in the oceans have been depicted at the whole community level, leaving out finer taxonomic resolution (i.e., microdiversity) that is crucial to conduct intra-population phylogeographic study, as commonly done for macroorganisms. Here, we present a new approach to unravel the bacterial phylogeographic patterns combining community-wide survey by 16S rRNA gene metabarcoding and intra-species resolution through the oligotyping method, allowing robust estimations of genetic and phylogeographic indices, and migration parameters. As a proof-of-concept, we focused on the bacterial genus Spirochaeta across three distant biogeographic provinces of the Southern Ocean; maritime Antarctica, sub-Antarctic Islands, and Patagonia. Each targeted Spirochaeta operational taxonomic units were characterized by a substantial intrapopulation microdiversity, and significant genetic differentiation and phylogeographic structure among the three provinces. Gene flow estimations among Spirochaeta populations support the role of the Antarctic Polar Front as a biogeographic barrier to bacterial dispersal between Antarctic and sub-Antarctic provinces. Conversely, the Antarctic Circumpolar Current appears as the main driver of gene flow, connecting sub-Antarctic Islands with Patagonia and maritime Antarctica. Additionally, historical processes (drift and dispersal limitation) govern up to 86% of the spatial turnover among Spirochaeta populations. Overall, our approach bridges the gap between microbial and macrobial ecology by revealing strong congruency with macroorganisms distribution patterns at the populational level, shaped by the same oceanographic structures and ecological processes.
Programme: 1044
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Damien Ertz, Neil Sanderson, Marc Lebouvier. (2021). Thelopsis challenges the generic circumscription in the Gyalectaceae and brings new insights to the taxonomy of Ramonia (Vol. 53).
Abstract: The genus Thelopsis was classified in the family Stictidaceae but its systematic position has never been investigated by molecular methods. In order to determine its family placement and to test its monophyly, fungal DNA of recent collections of Thelopsis specimens was sequenced. Phylogenetic analyses using nuLSU, RPB2 and mtSSU sequences reveal that members of Thelopsis form a monophyletic group within the genus Gyalecta as currently accepted. The placement of Thelopsis, including the generic type T. rubella, within the genus Gyalecta challenges the generic circumscription of this group because Thelopsis is well recognized by the combination of morphological characters: perithecioid ascomata, well-developed periphysoids, polysporous asci and small, few-septate ellipsoid-oblong ascospores. The sterile sorediate Opegrapha corticola is also placed in the Gyalectaceae as sister species to Thelopsis byssoidea + T. rubella. Ascomata of O. corticola are illustrated for the first time and support its placement in the genus Thelopsis. The hypothesis that O. corticola might represent the sorediate fertile morph of T. rubella is not confirmed because the species is phylogenetically and morphologically distinct. Thelopsis is recovered as polyphyletic, with T. melathelia being placed as sister species to Ramonia. The new combinations Thelopsis corticola (Coppins & P. James) Sanderson & Ertz comb. nov. and Ramonia melathelia (Nyl.) Ertz comb. nov. are introduced and a new species of Gyalecta, G. amsterdamensis Ertz, is described from Amsterdam and Saint-Paul Islands, characterized by a sterile thallus with discrete soralia. Petractis luetkemuelleri and P. nodispora are accommodated in the new genus Neopetractis, differing from the generic type (P. clausa) by having a different phylogenetic position and a different photobiont. Francisrosea bicolor Ertz & Sanderson gen. & sp. nov. is described for a sterile sorediate lichen somewhat similar to Opegrapha corticola but having an isolated phylogenetic position as sister to a clade including Gyalidea praetermissa and the genera Neopetractis and Ramonia. Gyalecta farlowii, G. nidarosiensis and G. carneola are placed in a molecular phylogeny for the first time. The taxonomic significance of morphological characters in Gyalectaceae is discussed.
Keywords: Arthoniales Gyalectales lichen multispory phylogeny
Programme: 1167
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J. Krug, J. Weiss, O. Gagliardini, G. Durand. (2013). A new calving law based on continuous damage and
fracture mechanics.
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