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Author Yushiro Fujii, Kenji Satake, Shingo Watada, Tung-Cheng Ho doi  openurl
  Title Re-examination of Slip Distribution of the 2004 Sumatra–Andaman Earthquake (Mw 9.2) by the Inversion of Tsunami Data Using Green’s Functions Corrected for Compressible Seawater Over the Elastic Earth Type Journal
  Year 2021 Publication Pure and Applied Geophysics Abbreviated Journal  
  Volume 178 Issue (down) 12 Pages 4777-4796  
  Keywords 2004 Sumatra–Andaman earthquake far-field tsunami waveform phase-corrected Green’s function slip distribution tsunami data inversion  
  Abstract We re-examined the slip distribution on faults of the 2004 Sumatra–Andaman (M 9.1 according to USGS) earthquake by the inversion of tsunami data with phase-corrected Green’s functions applied to linear long waves. The correction accounts for the effects of compressibility of seawater, elasticity of solid earth, and gravitational potential variation associated with the motion of mass to reproduce the delayed arrivals and the reversed phase of the first tsunami waves. We used sea surface height (SSH) data from satellite altimetry (SA) measurements along five tracks, and the tsunami waveforms recorded at tide gauges (TGs) and ocean bottom pressure gauges (OBPGs) in and around the Indian Ocean. The inversion results for both data sets for different rupture velocities (Vr) show that the reproducibility of the spatiotemporal SSHs and tsunami waveforms is improved by the phase corrections, although the effects are not so significant within the Indian Ocean. The best slip distribution model from joint inversion of SA, TG and OBPG data with Vr of 1.3 km/s shows the largest slips of 16–25 m off Sumatra Island, large slips of 2–11 m off the Nicobar Islands, and moderate slips of 2–6 m in the Andaman Islands. The inversion results reproduce the far-field tsunami waveforms well at distant stations even more than 13,000–25,000 km from the epicenter. The total source length is about 1400 km and the seismic moment is Mw 9.2, longer and larger than that of our previous estimates based on TG records.  
  Programme 688  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1420-9136 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8411  
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Author Jean-Pierre Féral, Marc Verlaque, Sebastián Rosenfeld, Elie Poulin, Anne Chenuil, Thomas Saucède doi  openurl
  Title The Marine Vegetation of the Kerguelen Islands: History of Scientific Campaigns, Inventory of the Flora and First Analysis of Its Biogeographical Affinities Type Journal
  Year 2021 Publication Cryptogamie, Algologie Abbreviated Journal  
  Volume 42 Issue (down) 12 Pages 173-216  
  Keywords  
  Abstract Conceived as a baseline for the management and conservation of the marine protected area of the French Southern Territories (réserve naturelle nationale des Terres australes françaises), the checklist of marine macroalgae of the Kerguelen Islands was updated based on an extensive review of the literature and scientific databases, from the first report of the Ross expedition, in 1840, to the most recent works. This work was also conceived as a starting point for forthcoming investigations using molecular systematics tools and for monitoring the effects of global change on sub-Antarctic marine ecosystems. After a brief history of scientific campaigns, a list of 166 species was established (103 Rhodophyta, 35 Chlorophyta and 28 Ochrophyta [Phaeophyceae]). Molecular systematics studiess have shown the existence of recurrent discrepancies between the established, morphology-based taxonomy and molecular species delimitation, calling for a revision of systematics. Nevertheless, a first analysis of biogeographical affinities of the marine flora of the Kerguelen Islands is carried out and preliminary results are partially congruent with the main regions currently recognized in the Southern Ocean suggesting the importance of long-distance dispersal to explain the observed distribution patterns.  
  Programme 1044  
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  ISSN 0181-1568, 1776-0984 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8440  
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Author Manfred R. Enstipp, Charles-André Bost, Céline Le Bohec, Nicolas Chatelain, Henri Weimerskirch, Yves Handrich file  doi
openurl 
  Title The early life of king penguins: ontogeny of dive capacity and foraging behaviour in an expert diver Type Journal
  Year 2021 Publication The Journal of Experimental Biology Abbreviated Journal  
  Volume 224 Issue (down) 12 Pages jeb242512  
  Keywords Animals Behavior, Animal Bio-logging Diving Feeding Behavior Foraging proficiency Ontogeny Seabirds Spheniscidae Temperature Wiggles  
  Abstract The period of emancipation in seabirds, when juveniles change from a terrestrial existence to a life at sea, is associated with many challenges. Apart from finding favourable foraging sites, they have to develop effective prey search patterns and physiological capacities that enable them to capture sufficient prey to meet their energetic needs. Animals that dive to forage, such as king penguins (Aptenodytes patagonicus), need to acquire an adequate breath-hold capacity, allowing them to locate and capture prey at depth. To investigate the ontogeny of their dive capacity and foraging performance, we implanted juvenile king penguins before their first departure to sea and also adult breeders with a data-logger recording pressure and temperature. We found that juvenile king penguins possess a remarkable dive capacity when leaving their natal colony, enabling them to conduct dives in excess of 100 m within their first week at sea. Despite this, juvenile dive/foraging performance, investigated in relation to dive depth, remained below the adult level throughout their first year at sea, probably reflecting physiological limitations as a result of incomplete maturation. A significantly shallower foraging depth of juveniles, particularly during their first 5 months at sea, could also indicate differences in foraging strategy and targeted prey. The initially greater wiggle rate suggests that juveniles fed opportunistically and also targeted different prey from adults and/or that many of the wiggles of juveniles reflect unsuccessful prey-capture attempts, indicating a lower foraging proficiency. After 5 months, this difference disappeared, suggesting sufficient physical maturation and improvement of juvenile foraging skills.  
  Programme 137,394  
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  Corporate Author Thesis Bachelor's thesis  
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  ISSN 1477-9145 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8473  
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Author Mathilde Poirier, Dominique Fauteux, Gilles Gauthier, Florent Domine, Jean-François Lamarre doi  openurl
  Title Snow hardness impacts intranivean locomotion of arctic small mammals Type Journal
  Year 2021 Publication Ecosphere Abbreviated Journal  
  Volume 12 Issue (down) 11 Pages e03835  
  Keywords Arctic burrowing behavior digging fossorial hardness lemming locomotion rain-on-snow rodent snow subnivean tunnel  
  Abstract Fossorial locomotion is often considered as the most energetically costly of all terrestrial locomotion. Small arctic rodents, such as lemmings, dig tunnels not only in the soil but also through the snowpack, which is present for over 8 months of the year. Lemmings typically dig in the softest snow layer called the depth hoar but with climate change, melt-freeze and rain-on-snow (ROS) events are expected to increase in the Arctic, leading to a higher frequency of hardened snowpacks. We assessed the impacts of snow hardness on the locomotion of two lemming species showing different morphological adaptations for digging. We hypothesized that an increase in snow hardness would (1) decrease lemming performance and (2) increase their effort while digging, but those responses would differ between lemming species. We exposed four brown lemmings (Lemmus trimucronatus) and three collared lemmings (Dicrostonyx groenlandicus) to snow of different hardness (soft, hard, and ROS) during 30-min trials (n = 63 trials) in a cold room and filmed their behavior. We found that the digging speed and tunnel length of both species decreased with snow hardness and density, underlining the critical role of snow properties in affecting lemming digging performance. During the ROS trials, time spent digging by lemmings increased considerably and they also started using their incisors to help break the hard snow, validating our second hypothesis. Overall, digging performance was higher in collared lemmings, the species showing more morphological adaptations to digging, than in brown lemmings. We conclude that the digging performance of lemming is highly dependent on snowpack hardness and that the anticipated increase in ROS events may pose a critical energetic challenge for arctic rodent populations.  
  Programme 1042  
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  Series Volume Series Issue Edition  
  ISSN 2150-8925 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8028  
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Author Alexandra Lavrillier, Semen Gabyshev doi  openurl
  Title An Indigenous science of the climate change impacts on landscape topography in Siberia Type Journal
  Year 2021 Publication Ambio Abbreviated Journal  
  Volume 50 Issue (down) 11 Pages 1910-1925  
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  Abstract As with many Indigenous Peoples, the Siberian Evenki nomadic reindeer herders and hunters have observed increasing consequences of climate change on the cryosphere and biodiversity. Since 2017, they have observed previously unthinkable changes in topography. Based exclusively on an Evenki Indigenous Ecological Knowledge system-social anthropology coproduction and community-based continuous observation from 2013, this paper analyses what a Subarctic People observes, knows, does not know, hypothesizes, and models (collectively or individually) about climate change impacts on Indigenous landscape types typical for local river systems. These landscapes are crucial tools for traditional activities. To the nomads, the landscape changes emerge from general anomalies: competition from new plant species; atmosphere–ground–vegetation interactions; icing blisters decrease; rising receding river water interactions; the formation of new soil, ice, and snow types; increasing ground, air, and water temperatures; and the (non)circulation of harsh air throughout the snowpack. We demonstrate the science-like structure and value of Indigenous typologies and hypotheses.  
  Programme 1127  
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  Series Volume Series Issue Edition  
  ISSN 1654-7209 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 7627  
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Author M. Legrand, R. Weller, S. Preunkert, B. Jourdain doi  openurl
  Title Ammonium in Antarctic Aerosol: Marine Biological Activity Versus Long-Range Transport of Biomass Burning Type Journal
  Year 2021 Publication Geophysical Research Letters Abbreviated Journal  
  Volume 48 Issue (down) 11 Pages e2021GL092826  
  Keywords aerosol black carbon ammonium Antarctic biomass burning et marine biota oxalate potassium  
  Abstract Year-round records of the ionic composition of Antarctic aerosol were obtained at the inland Dome C (DC) and coastal Neumayer (NM) sites, with additional observations of black carbon (BC) at NM. Discussions focus on the origin of ammonium in Antarctica. This first Antarctic atmospheric study of several species emitted by biomass burning (BB) indicates that BC and oxalate reach a maximum in October in relation to BB activity in the southern hemisphere. Ammonium reaches a maximum 2 months later, suggesting that BB remains a minor ammonium source there. The ammonium maximum in December coincides with the occurrence of diatom blooms in the austral ocean, suggesting that oceanic ammonia emissions are the main source of ammonium in Antarctica. The ammonium to sulfur-derived biogenic species molar ratio of 0.15 in summer suggests far lower ammonia emissions from the Antarctic oceans than midlatitude southern oceans.  
  Programme 903  
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  Series Volume Series Issue Edition  
  ISSN 1944-8007 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8252  
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Author Stefan Osterwalder, Sarrah M. Dunham-Cheatham, Beatriz Ferreira Araujo, Olivier Magand, Jennie L. Thomas, Foteini Baladima, Katrine Aspmo Pfaffhuber, Torunn Berg, Lei Zhang, Jiaoyan Huang, Aurélien Dommergue, Jeroen E. Sonke, Mae Sexauer Gustin doi  openurl
  Title Fate of Springtime Atmospheric Reactive Mercury: Concentrations and Deposition at Zeppelin, Svalbard Type Journal
  Year 2021 Publication ACS Earth and Space Chemistry Abbreviated Journal  
  Volume 5 Issue (down) 11 Pages 3234-3246  
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  Abstract Mid-latitude atmospheric elemental mercury (Hg) emissions undergo extensive oxidation to reactive Hg (RM) compounds during Arctic polar sunrise, resulting in enhanced atmospheric deposition that impacts Arctic marine wildlife and humans. It has been difficult to estimate RM dry deposition, because RM concentrations, compounds, and their deposition velocities are ill-defined. Here, we investigate RM concentrations sampled with membrane-based methods and find these to exceed denuder-based RM detection by 5 times at the Zeppelin Observatory on Svalbard (March 26–July 24, 2019). Measured dry deposition of gaseous oxidized Hg was about half of the modeled RM deposition, demonstrating that particulate-bound Hg was an important component of dry deposition. Using thermal membrane desorption, RM chemistry was found to be dominated by Hg–Cl/Br (51%) and Hg–N (45%) compounds. Back-trajectory analysis indicated that Hg–Br/Cl compounds were predominantly advected from within the marine boundary layer (sea ice exposure), while Hg–N originated from the free troposphere. Weekly average RM compound-specific dry deposition velocities ranged from 0.12 to 0.49 cm s–1, with a net RM dry deposition of 1.9 μg m–2 (1.5–2.5 μg m–2; 95% confidence interval) that exceeds the mean annual Hg wet deposition flux in Svalbard. Overall, we find that springtime atmospheric RM deposition has been underestimated in the Arctic marine environment.  
  Programme 1028  
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  Notes Approved yes  
  Call Number Serial 8361  
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Author Hugo Saiz, David Renault, Sara Puijalon, Miguel Barrio, Mathilde Bertrand, Matteo Tolosano, Aurélien Pierre, Charly Ferreira, Clémentine Prouteau, Anne-Kristel Bittebiere doi  openurl
  Title Huff and puff and blow down: invasive plants traits response to strong winds at the Southern Oceanic Islands Type Journal
  Year 2021 Publication Oikos Abbreviated Journal  
  Volume 130 Issue (down) 11 Pages 1919-1929  
  Keywords environmental filter functional traits hypervolume Iles Kerguelen intraspecific variability mechanical stress  
  Abstract Invasions constitute a major driver of biodiversity changes. Insular plant communities are particularly vulnerable to invasions and are relevant models for investigating mechanisms supporting the establishment and spread of introduced plants. Terrestrial flora of sub-Antarctic islands must often thrive in highly windy habitats, thus imposing strong mechanical constraints on individuals. Many alien plants at the sub-Antarctic islands are of tropical or temperate origins, where they were exposed to less stringent wind conditions. As wind likely represents a strong environmental filter for the successful establishment and further geographic spread of plants, they should have developed responses to resist and successfully colonize the Iles Kerguelen. We studied responses to wind of three herbaceous species that are invasive at Iles Kerguelen. We sampled plant individuals at different locations, under windy and sheltered conditions. Traits related to wind avoidance and tolerance and to resource acquisition were measured. We additionally assessed individual performance (biomass) to determine the consequences of trait variations. We focused on trait mean and variance, in particular, through the calculation of hypervolumes. This study emphasized that wind has important effects on plant economics spectrum, including traits involved in mechanical avoidance and light acquisition, with varying strategies, which seem to depend on the biological type of the species (grass versus non-grass). Wind generally reduces individual performance, and this negative effect is not direct but operates through the modification of plant trait values. Furthermore, analyses performed at the hypervolume scale indicate that not only functional trait mean but also its variability account for plant performance. The existence of contrasting growth strategies to cope with local environmental conditions suggests that invaders will be able to occupy different niches, which may ultimately impact local communities. Our results highlight the importance of considering multi-traits responses to meaningfully capture plant adjustments to stress.  
  Programme 136  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1600-0706 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8372  
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Author Casey Youngflesh, Yun Li, Heather J. Lynch, Karine Delord, Christophe Barbraud, Rubao Ji, Stephanie Jenouvrier doi  openurl
  Title Lack of synchronized breeding success in a seabird community: extreme events, niche separation, and environmental variability Type Journal
  Year 2021 Publication Oikos Abbreviated Journal  
  Volume 130 Issue (down) 11 Pages 1943-1953  
  Keywords Antarctica environmental indicators extreme events global change niche separation synchrony  
  Abstract Synchrony in ecological systems, the degree to which elements respond similarly over time or space, can inform our understanding of how ecosystems function and how they are responding to global change. While studies of ecological synchrony are often focused on within-species dynamics, synchrony among species may provide important insights into how dynamics of one species are indicative of conditions relevant to the larger community, with both basic and applied implications. Ecological theory suggests there may be conditions under which communities might exhibit increased synchrony, however, the degree to which these patterns are borne out in natural systems is currently unknown. We used long-term breeding success data from a community of Antarctic seabirds to assess the degree of interspecific, community synchrony, and the role that extreme events play in driving these dynamics. We assessed theoretical links between community synchrony, niche separation, and environmental variability using data from this and three other seabird communities as well as a simulation study. Results show that reproductive success for individual species in the Antarctic seabird community fluctuated relatively independently from one another, resulting in little synchrony across this community, outside of extreme years. While an exceptionally poor year for a given species was not necessarily associated with an exceptionally poor year for any other species, one community-wide extreme year existed. When compared to other seabird communities, this group of Antarctic seabirds exhibited lower overall synchrony and higher estimated niche separation, supporting theoretical predictions. Empirical and simulation-derived results suggest that communities where temporal variation is small for conditions in which species respond substantially differently, and large for conditions in which species respond similarly, may exhibit more synchronous dynamics. Identifying where and why synchronous dynamics might be more apparent has the potential to inform how ecological communities might respond to future global change.  
  Programme 109  
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  ISSN 1600-0706 ISBN Medium  
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  Notes Approved yes  
  Call Number Serial 8385  
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Author María José Frugone, Theresa L. Cole, María Eugenia López, Gemma Clucas, Pável Matos-Maraví, Nicolás A. Lois, Pierre Pistorius, Francesco Bonadonna, Phil Trathan, Andrea Polanowski, Barbara Wienecke, Andrea Raya-Rey, Klemens Pütz, Antje Steinfurth, Ke Bi, Cynthia Y. Wang-Claypool, Jonathan M. Waters, Rauri C. K. Bowie, Elie Poulin, Juliana A. Vianna doi  openurl
  Title Taxonomy based on limited genomic markers may underestimate species diversity of rockhopper penguins and threaten their conservation Type Journal
  Year 2021 Publication Diversity and Distributions Abbreviated Journal  
  Volume 27 Issue (down) 11 Pages 2277-2296  
  Keywords Eudyptes genomics rockhopper penguins species delimitation  
  Abstract Aim Delimiting recently diverged species is challenging. During speciation, genetic differentiation may be distributed unevenly across the genome, as different genomic regions can be subject to different selective pressures and evolutionary histories. Reliance on limited numbers of genetic markers that may be underpowered can make species delimitation even more challenging, potentially resulting in taxonomic inconsistencies. Rockhopper penguins of the genus Eudyptes comprise three broadly recognized taxa: northern (E. moseleyi), southern (E. chrysocome) and eastern rockhopper (E. filholi). Their taxonomic status has been controversial for decades, with researchers disagreeing about whether E. chrysocome and E. filholi are distinct species or conspecific. Our goal is to evaluate genome-wide patterns of divergence to evaluate genetic differentiation and species delimitation in rockhopper penguins, and to assess which mechanisms may underlie previous discordance among nuclear versus mitochondrial analyses. Location Sub-Antarctic and temperate coastal regions of the Southern Hemisphere. Methods We generated reduced-representation genomic libraries using double digest restriction-site associated DNA (ddRAD) sequencing to evaluate genetic differentiation, contemporary migration rates and admixture among colonies of rockhopper penguins. Results The extent of genetic differentiation among the three taxa was consistently higher than population-level genetic differentiation found within these and other penguin species. There was no evidence of admixture among the three taxa, suggesting the absence of ongoing gene flow among them. Species delimitation analyses based on molecular data, along with other lines of evidence, provide strong support for the taxonomic distinction of three species of rockhopper penguins. Main conclusions Our results provide strong support for the existence of three distinct species of rockhopper penguins. The recognition of this taxonomic diversity is crucial for the management and conservation of this widely distributed species group. This study illustrates that widespread dispersive seabird lineages lacking obvious morphological differences may nevertheless have complex evolutionary histories and comprise cryptic species diversity.  
  Programme 354  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1472-4642 ISBN Medium  
  Area Expedition Conference  
  Notes Approved yes  
  Call Number Serial 8421  
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