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. (2017). (Vol. 272-273).
Keywords: Kerguelen Oceanic plateau Spinel harzburgites Ultra-refractory Xenoliths
Programme: 1077
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Xu, G.; Frey, F.A.; Weis, D.; Scoates, J.S.; Giret, A. (2007). Flood basalts from Mt. Capitole in the central Kerguelen Archipelago: Insights into the growth of the archipelago and source components contributing to plume-related volcanism. Geochem. Geophys. Geosyst., 8.
Abstract: The Kerguelen Archipelago, constructed on the submarine Northern Kerguelen Plateau, is attributed to Cenozoic volcanism arising from the Kerguelen hot spot. Geochemical studies of 325 to 1000 m thick lava sections of the ?30 to 25 Ma flood basalt forming the bulk of the archipelago show a temporal change from older tholeiitic basalt to younger slightly alkalic basalt. This compositional transition is expressed in a 630 m lava section at Mt. Capitole where the lava sequence is lowermost tholeiitic basalt overlain by slightly alkalic basalt overlain by plagioclase-rich cumulates that are mixtures of plagioclase-phyric basalt and more evolved magmas. During growth of the archipelago, magma supply from the hot spot was variable and at times sufficiently low to enable extensive crystal fractionation; e.g., at Mt. Capitole and nearby Mt. Tourmente only 10 of 120 lava flows have >6 wt% MgO. On the basis of this study and previous isotopic data for the ?34 Ma submarine lavas erupted on the Northern Kerguelen Plateau, other flood basalt sections in the Kerguelen Archipelago, and younger lavas erupted in the archipelago and at Heard Island, there is significant Sr, Nd, Hf, and Pb isotopic heterogeneity that can be explained by two stages of mixing. The first mixing event, best shown by the submarine lavas, is between components that are related to Indian Ocean mid-ocean ridge basalt (MORB) and the Kerguelen hot spot. From ?34 Ma to <1 Ma, on average the proportion of the MORB-related component decreased. Subsequently, a second mixing process involved addition of a component with relatively high 87Sr/86Sr (>0.7060) and low 143Nd/144Nd (<0.5125) and 176Hf/177Hf (<0.2827) and nonradiogenic Pb isotope ratios (<17.9 for 206Pb/204Pb). We infer that this component was lower continental crust.
Keywords: Kerguelen mantle plume; Kerguelen Archipelago; Mt. Capitole; lower continental crust; Sr; Nd; Hf; Pb isotopic ratios; 1037 Geochemistry: Magma genesis and partial melting; 1038 Geochemistry: Mantle processes; 1065 Geochemistry: Major and trace element geochemistry
Programme: 444
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Gregory B. Cunningham, Richard W. Van Buskirk, Mark J. Hodges, Gabrielle A. Nevitt. (2012). Responses of common diving petrel chicks (Pelecanoides urinatrix) to burrow and colony specific odours in a simple wind tunnel (Vol. 24).
Abstract: Researchers have previously assumed that common diving petrels (Pelecanoides urinatrix) have a limited sense of smell since they have relatively small olfactory bulbs. A recent study, however, showed that adult diving petrels prefer the scent of their own burrow compared to burrows of other diving petrels, implying that personal scents contribute to the burrow's odour signature. Because diving petrels appear to be adapted to use olfaction in social contexts, they could be a useful model for investigating how chemically mediated social recognition develops in birds. A first step is to determine whether diving petrel chicks can detect familiar and unfamiliar odours. We compared behavioural responses of chicks to three natural stimuli in a wind tunnel: soil collected from their burrow or colony, and a blank control. During portions of the experiment, chicks turned the least and walked the shortest distances in response to odours from the nest, which is consistent with their sedentary behaviour within the burrow. By contrast, behaviours linked to olfactory search increased when chicks were exposed to blank controls. These results suggest that common diving petrel chicks can detect natural olfactory stimuli before fledging, and lay the foundation for future studies on the role of olfaction in social contexts for this species.
Keywords: Kerguelen kin recognition olfaction procellariiform
Programme: 109
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A. Jaffal, N. Givaudan, S. Betoulle, A. Terreau, S. Paris-Palacios, S. Biagianti-Risbourg, E. Beall, H. Roche. (2011). Polychlorinated biphenyls in freshwater salmonids from the Kerguelen Islands in the Southern Ocean (Vol. 159).
Keywords: Kerguelen Islands PCB accumulation Salmonids Sub-Antarctic area
Programme: 409
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. (2015). Insects in fluctuating thermal environments.
. Annu. Rev. Entomol., 60, 123–40.
Abstract: All climate change scenarios predict an increase in both global temperature means and the magnitude of seasonal and diel temperature variation. The nonlinear relationship between temperature and biological processes means that fluctuating temperatures lead to physiological, life history, and ecological consequences for ectothermic insects that diverge from those predicted from constant temperatures. Fluctuating temperatures that remain within permissive temperature ranges generally improve performance. By contrast, those which extend to stressful temperatures may have either positive impacts, allowing repair of damage accrued during exposure to thermal extremes, or negative impacts from cumulative damage during successive exposures. We discuss the mechanisms underlying these differing effects. Fluctuating temperatures could be used to enhance or weaken insects in applied rearing programs, and any prediction of insect performance in the field-including models of climate change or population performance-must account for the effect of fluctuating temperatures.
Keywords: Jensen's inequality, climate change, life history traits, temperature variations, thermal tolerance,
Programme: 136
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. (2012). Specific pathways for the incorporation of dissolved barium and molybdenum into the bivalve shell: An isotopic tracer approach in the juvenile Great Scallop (Pecten maximus)
. Mar. Environ. Res., 78, 15–25.
Keywords: Isotopes, Femtosecond laser ablation, Scallop shell, Barium, Molybdenum, Pecten maximus, Tracers, Biogeochemical cycle,
Programme: 1090
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. (2021). Seabird population changes following mammal eradication at oceanic Saint-Paul Island, Indian Ocean (Vol. 63).
Keywords: Island restoration Petrels Population growth rate Rats Shearwaters Terns
Programme: 109
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. (2012). Effects of climate change on an emperor penguin population: analysis of coupled demographic and climate models
. Glob Chang Biol, 18(9), 2756–2770.
Keywords: IPCC, sea ice, seabirds, stochastic climate forecast, stochastic matrix population model, uncertainties,
Programme: 109
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Chisham G, Freeman M P, Abel G A, Bristow W A, Marchaudon A, Ruohoniemi J M, Sofko G J, . (2009). Spatial distribution of average vorticity in the high-latitude ionosphere and its variation with interplanetary magnetic field direction and season
. J. Geophys. Res., 114(A9), A09301–.
Keywords: ionosphere, vorticity, field-aligned current, 2431 Ionosphere: Ionosphere/magnetosphere interactions, 2409 Ionosphere: Current systems, 2437 Ionosphere: Ionospheric dynamics, 2494 Ionosphere: Instruments and techniques, 2721 Magnetospheric Physics: Field-aligned currents and current systems,
Programme: 312;911
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Lukianova R, Hanuise C, Christiansen F, . (2008). Asymmetric distribution of the ionospheric electric potential in the opposite hemispheres as inferred from the SuperDARN observations and FAC-based convection model
. 1364-6826, 70(18), 2324–2335.
Abstract: We compare the SuperDARN convection patterns with the predictions of a new numerical model of the global distribution of ionospheric electric potentials. The model utilizes high-precision statistical maps of field-aligned currents (FAC) derived from measurements made by polar-orbiting low-altitude satellites. Both the solar and auroral precipitation contributions are included in order to derive the ionospheric conductance. Taking into account the electrodynamic coupling of the opposite hemispheres, the model allows one to obtain the convection patterns developed simultaneously in both hemispheres for given input parameters. SuperDARN, with its database containing global northern and southern convection maps, provides the unique opportunity to compare the model predictions of electric fields with observations. In the present study we focus on the effect of significant interhemispheric asymmetry governed by the IMF clock angle and solar zenith angle. We calculate the convection patterns for specific cases caused by the sign of BY and season and demonstrate the capability of the FAC-based model reproduce the radar observations. The simulation confirms that the solar zenith angle should be linked to the IMF clock angle to fully characterize the convection patterns. The model predicts that the cross-polar cap potential drop is regularly larger in the winter hemisphere than in the summer hemisphere.
Keywords: Ionosphere, Convection, Field-aligned currents, SuperDARN,
Programme: 312;911
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