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SAUCEDE T. (2008). An illustration of the French Research in Antarctic: a study of biodiversity patterns in the marine fauna..
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Gattacceca J., Rochette P., Denise M., Consolmagno G., Folco L. (2005). An impact origin for the foliation of ordinary chondrites. Earth Planet. Sci. Lett., 234, 351–368.
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Emile A. Okal, Nooshin Saloor, Stephen H. Kirby, Meredith Nettles. (2018). An implosive component to the source of the deep Sea of Okhotsk earthquake of 24 May 2013: Evidence from radial modes and CMT inversion (Vol. 281).
Abstract: We study the spectral amplitudes of the first two Earth radial modes, 0S0 and 1S0, excited by the Sea of Okhotsk earthquake of 24 May 2013, the largest deep event ever recorded, in the search for an isotropic component to its source. In contrast to the case of the 1994 Bolivian earthquake, we detect an implosive component MI=-1.1×1027 dyn*cm, equivalent to 3% of the full scalar moment, but 14% of the lone deviatoric component exciting the Earth’s radial modes. An independent moment tensor inversion, using the standard GlobalCMT algorithm but after relaxing its zero-trace constraint, similarly yields an implosive isotropic component, albeit with a larger amplitude, while it fails to document one in the case of the 1994 Bolivian deep earthquake. An implosive component to the source is expected in the model of transformational faulting in which deep earthquake rupture nucleates and grows upon transformation of metastable olivine to ringwoodite in the cold subducting slab. This interpretation is supported by quantitative estimates (0.9–4 m) of the thickness of the transformed shear zone, which scale favorably, relative to earthquake fault length, with the upper end of the range of laboratory results reported for ices, germanates and silicates. The resulting extent of the transformation in the metastable wedge is consistent with the local geometry of the deep slab, as recently determined by rupture modeling and aftershock distribution. Our results are in contrast to those for the two runner-up largest deep earthquakes, the 1994 Bolivian and 1970 Colombian shocks, for which a similar isotropic component could not be detected. We attribute this difference to variability in the ratio of isotropic to deviatoric components, which combined with the smaller size of the 1970 and 1994 events, would make any putative implosive component fall below detection levels, especially in the case of the 1970 Colombian earthquake for which only analog narrow-band records were available.
Programme: 133
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Morganti Andrea; Becagli Silvia; Castellano Emiliano; Severi Mirko; Traversi Rita; Udisti Roberto. (2007). An improved flow analysis-ion chromatography method for determination of cationic and anionic species at trace levels in Antarctic ice cores. Anal. Chim. Acta, 603(2), 190–198.
Abstract: A method was developed for the quantitative determination of cations and anions in Antarctic ice cores at microgL(-1) and sub-microgL(-1) levels by ion chromatography (IC), after ultra-clean decontamination procedures. Strict manipulation and decontamination procedures were used in sub-sampling, in order to minimise sample contamination. Na+, NH4+, K+, Mg2+ and Ca2+ were determined by 12-min isocratic elution (H2SO4 eluent). Contemporaneously, in a parallel device, F-, MSA (methanesulfonic acid), Cl-, NO3- and SO4(2-) were analysed in a single 12-min run with multiple-step elution using Na2CO3/NaHCO3 as eluent. Melted ice samples were pumped from their still-closed containers (polystyrene accuvettes with polyethylene caps), shared between the two ion chromatographic systems, online filtered (0.45 microm Teflon membrane) and pre-concentrated (anions and cations pre-concentration columns) using a flow analysis system, thus avoiding uptake of contaminants from the laboratory atmosphere. Sensitivity, linear range, reproducibility and detection limit were evaluated for each chemical species. Anion or cation detection limits ranged from 0.01 to 0.15 microgL(-1) by using a relatively small sample volume (1.5 mL). Such values are significantly lower than those reported in literature for almost all the components. These methods were successfully applied to the analysis of cations and anions at trace levels in the Dome C ice core. The composition of the atmospheric aerosol for the last 850 kyr was reconstructed by high-resolution continuous chemical stratigraphies. Concentration trends in the last nine glacial-interglacial climatic cycles were shown and briefly discussed.
Programme: 1181
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Alexandra Lavrillier, Semen Gabyshev. (2021). An Indigenous science of the climate change impacts on landscape topography in Siberia (Vol. 50).
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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Leclaire Sarah, Merkling Thomas, Raynaud Christine, Giacinti Géraldine, Bessière Jean-Marie, Hatch Scott, Danchin Étienne, . (2011). An individual and a sex odor signature in kittiwakes? Study of the semiochemical composition of preen secretion and preen down feathers
. Naturwissenschaften, 98(7), 615–624.
Abstract: The importance of olfaction in birds social behavior has long been denied. Avian chemical signaling has thus been relatively unexplored. The black-legged kittiwake provides a particularly appropriate model for investigating this topic. Kittiwakes preferentially mate with genetically dissimilar individuals, but the cues used to assess genetic characteristics remain unknown. As in other vertebrates, their body odors may carry individual and sexual signatures thus potentially reliably signaling individual genetic makeup. Here, we test whether body odors in preen gland secretion and preen down feathers in kittiwakes may provide a sex and an individual signature. Using gas chromatography and mass spectrometry, we found that male and female odors differ quantitatively, suggesting that scent may be one of the multiple cues used by birds to discriminate between sexes. We further detected an individual signature in the volatile and nonvolatile fractions of preen secretion and preen down feathers. These results suggest that kittiwake body odor may function as a signal associated with mate recognition. It further suggests that preen odor might broadcast the genetic makeup of individuals, and could be used in mate choice to assess the genetic compatibility of potential mates.
Keywords: Biomedical and Life Sciences,
Programme: 1162
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Beans C., Courcot L., Goffart A., Koubbi P., Vallet C., Vandeputte A., Volkaert F. & Hecq J.H. (2005). An initial study on the diet of post-larval antarctic silverfish (Pleuragramma antarcticum, Boulanger 1902) from Antarctic coastal waters.
Abstract: 29th Annual Larval Fish Conference – AFS ELHS, Barcelona, Espagne.
Programme: 281
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Fund F, Perosanz F, Testut L, Loyer S, . (2013). An Integer Precise Point Positioning technique for sea surface observations using a GPS buoy
. Adv Space Res, 51(8), 1311–1322.
Abstract: GPS data dedicated to sea surface observation are usually processed using differential techniques. Unfortunately, the precision of resulting kinematic positions is baseline-length dependent. So, high precision sea surface observations using differential GPS techniques are limited to coasts, lakes, and rivers. Recent improvements in GPS satellite products (orbits, clocks, and phase biases) make phase ambiguity fixing at the zero difference level achievable and opens up the observation of the sea surface without geographical constraints. This paper recalls the concept of the Integer Precise Point Positioning technique and discusses the precision of GPS buoy positioning. A sequential version of the GINS software has been implemented to achieve single epoch GPS positioning. We used 1 Hz data from a two week GPS campaign conducted in the Kerguelen Islands. A GPS buoy has been moored close to a radar gauge and 90 m away from a permanent GPS station. This infrastructure offers the opportunity to compare both kinematic Integer Precise Point Positioning and classical differential GPS positioning techniques to in situ radar gauge data. We found that Precise Point Positioning results are not significantly biased with respect to radar gauge data and that horizontal time series are consistent with differential processing at the sub-centimetre precision level. Nevertheless, standard deviations of height time series with respect to radar gauge data are typically [45] cm. The dominant driver for noise at this level is attributed to errors in tropospheric estimates which propagate into position solutions.
Keywords: GPS, Ambiguity fixing, Tropospheric delays, Buoy, Radar gauge,
Programme: 688
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Tuck Geoffrey N, Thomson Robin B, Barbraud Christophe, Delord Karine, Louzao Maite, Herrera Miguel, Weimerskirch Henri, . (2015). An integrated assessment model of seabird population dynamics: can individual heterogeneity in susceptibility to fishing explain abundance trends in Crozet wandering albatross?
. J Appl Ecol, 52(4), 950–959.
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N. Van der Putten, J. -P. Hébrard, C. Verbruggen, B. Van de Vijver, J. -R. Disnar, S. Spassov, J. -L. de Beaulieu, M. De Dapper, D. Keravis, J. Hus, N. Thouveny, Y. Frenot. (2008). An integrated palaeoenvironmental investigation of a 6200 year old peat sequence from Ile de la Possession, Iles Crozet, sub-Antarctica (Vol. 270).
Abstract: A 6200 year old peat sequence, cored in a volcanic crater on the sub-Antarctic Ile de la Possession (Iles Crozet), has been investigated, based on a multi-proxy approach. The methods applied are macrobotanical (mosses, seeds and fruits) and diatom analyses, complemented by geochemical (Rock-Eval6) and rock magnetic measurements. The chronology of the core is based on 5 radiocarbon dates. When combining all the proxy data the following changes could be inferred. From the onset of the peat formation (6200 cal yr BP) until ca. 5550 cal yr BP, biological production was high and climatic conditions must have been relatively warm. At ca. 5550 cal yr BP a shift to low biological production occurred, lasting until ca. 4600 cal yr BP. During this period the organic matter is well preserved, pointing to a cold and/or wet environment. At ca. 4600 cal yr BP, biological production increased again. From ca. 4600 cal yr BP until ca. 4100 cal yr BP a “hollow and hummock” micro topography developed at the peat surface, resulting in the presence of a mixture of wetter and drier species in the macrobotanical record. After ca. 4100 cal yr BP, the wet species disappear and a generally drier, acidic bog came into existence. A major shift in all the proxy data is observed at ca. 2800 cal yr BP, pointing to wetter and especially windier climatic conditions on the island probably caused by an intensification and/or latitudinal shift of the southern westerly belt. Caused by a stronger wind regime, erosion of the peat surface occurred at that time and a lake was formed in the peat deposits of the crater, which is still present today.
Keywords: Diatoms Geochemical analysis Holocene Iles Crozet Macrofossil record Palaeoclimate Palaeoecology Rock magnetism Sub-Antarctic
Programme: 136
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