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Author |
Chuxian Li, Jeroen E. Sonke, Gaël Le Roux, Natalia Piotrowska, Nathalie Van der Putten, Stephen J. Roberts, Tim Daley, Emma Rice, Roland Gehrels, Maxime Enrico, Dmitri Mauquoy, Thomas P. Roland, François De Vleeschouwer |
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Title |
Unequal Anthropogenic Enrichment of Mercury in Earth’s Northern and Southern Hemispheres |
Type |
Journal |
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Year |
2020 |
Publication |
ACS Earth and Space Chemistry |
Abbreviated Journal |
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Volume |
4 |
Issue |
11 |
Pages |
2073-2081 |
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Abstract |
Remote Northern Hemisphere (NH) and Southern Hemisphere (SH) lake sediment and peat records of mercury (Hg) deposition have shown a ×3 to ×5 Hg enrichment since pre-industrial times (<1880 AD), leading to the perception that global atmospheric Hg enrichment is moderate and uniform across the hemispheres. Anthropogenic Hg emissions in the NH are, however, approximately 4 times higher than those in the SH. Here, we reconstruct atmospheric Hg deposition in four remote SH peatlands and review sediment and peat Hg records from both hemispheres. We observe a ×4 all-time enrichment in SH Hg deposition from pre-anthropogenic (<1450 AD) to the late 20th-century periods, which is lower than the large ×16 all-time enrichment in NH Hg deposition. We attribute this difference to lower anthropogenic Hg emissions in the SH, and higher natural atmospheric SH Hg concentrations, supported by ×2 higher natural background Hg accumulation in SH peat records. We suggest that the higher SH natural atmospheric Hg deposition reflects the SH land–ocean distribution, and is driven by important SH marine Hg emissions. Our findings indicate that atmospheric Hg background levels and anthropogenic enrichment in both hemispheres are different and should be taken into account in international Hg assessments and environmental policy. |
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1065,1133 |
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Bachelor's thesis |
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Approved |
yes |
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Call Number |
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Serial |
7791 |
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Author |
Liubomira Romanova, Charles Stépanoff, Norbert Telmon, Eric Crubézy |
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Title |
Health access inequities and magic medicine: the first ancient evidence? |
Type |
Journal |
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Year |
2020 |
Publication |
The Lancet |
Abbreviated Journal |
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Volume |
395 |
Issue |
10233 |
Pages |
1343-1344 |
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Keywords |
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Abstract |
Inequities in access to the latest advances in health care and effective drugs constitute public health problems today,1 but was this also the case in ancient societies when practitioners used traditional medicines with limited means? The excavation of frozen graves in Yakutia (present day eastern Siberia, Russia) dating from 1700 CE2 led to the identification of a woman, buried almost naked, covered with a magnificent robe and with half a horse bit in her mouth (figure). The other half of the horse bit was found in the trunk behind her head with her earrings, bracelets, and signet rings. |
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Programme |
1038 |
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Thesis |
Bachelor's thesis |
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Publisher |
Elsevier |
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ISBN |
0140-6736, 1474-547X |
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yes |
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Call Number |
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Serial |
7666 |
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Author |
Chuxian Li, Jeroen E. Sonke, Gaël Le Roux, Nathalie Van der Putten, Natalia Piotrowska, Catherine Jeandel, Nadine Mattielli, Mathieu Benoit, Giles F. S. Wiggs, François De Vleeschouwer |
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Title |
Holocene dynamics of the southern westerly winds over the Indian Ocean inferred from a peat dust deposition record |
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Journal |
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Year |
2020 |
Publication |
Quaternary Science Reviews |
Abbreviated Journal |
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Volume |
231 |
Issue |
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Pages |
106169 |
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Keywords |
Amsterdam Island Anthropogenic activities Dust sources Peat Southern westerly winds |
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Abstract |
The southern westerly winds (SWW) play a major role in climate variability in Southern Hemisphere mid- and high-latitudes, regulating rainfall, ocean circulation, and the Southern Ocean carbon sink. Despite their importance, little is known about millennial scale changes in the SWW and how they have influenced the climate system in the past and interacted with the Earth’s surface elements, such as dust, nutrients and carbon. Here we present a dust record from a 6.6 kyr old peat core in Amsterdam Island (AMS) situated at the northern edge of the SWW (37°S) in the Southern Indian Ocean. Mineral dust flux was used to track atmospheric dust production, long-distance transport and subsequent deposition. Dust provenance was determined from rare earth element (REE) and Nd isotopic signatures (εNd) in the peat core, compared with a reference dataset of Southern Hemisphere dust sources. Using a multi-proxy mixing model, the εNd and REE ratios show a relatively uniform mixture of ca. 40% local, 15% Southern African and 45% Southern South American dust sources since 6.6 cal kyr BP. However, from 1910 AD onwards, there is a doubling in the contribution from Southern Africa (32%). Two mineral dust flux minima occur at 6.2–4.9 cal kyr BP and 3.9–2.7 cal kyr BP, interpreted as periods with equatorward-shifted and/or strengthened SWW at the northern edge of the wind belt. Conversely, periods of higher dust flux at 6.6–6.2 cal kyr BP, 4.9–3.9 cal kyr BP, and 1.4 cal kyr BP onwards are interpreted as poleward-shifted and/or weakened SWW. These interpretations are based on the findings that higher (lower) wind speeds lead to enhanced (less) removal of distal dust on the way to AMS, by wet deposition and turbulence. Published Holocene SWW records at the northern edge of the wind belt (33–41°S) covering South-America, Southern-Africa and Australia, show much variability over the last 6.6 kyr. We suggest this reflects complex regional climate variability in the different SH longitudinal sectors, indicating that SWW are not zonally homogeneous at the northern edge of the wind belt. The recent shift in dust provenance is not accompanied by enhanced total dust deposition at AMS. We therefore suggest that human impact (e.g., land use changes) and drier climate conditions in Southern Africa have led to enhanced dust mobilization. |
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Programme |
1065,1133 |
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Corporate Author |
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Thesis |
Bachelor's thesis |
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Place of Publication |
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Series Issue |
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ISSN |
0277-3791 |
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Approved |
yes |
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Call Number |
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Serial |
8193 |
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Author |
Héloïse Barbel, Dominique Todisco, Najat Bhiry |
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Title |
A geochemical investigation of an Early Inuit semi-subterranean winter dwelling in a periglacial context |
Type |
Journal |
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Year |
2020 |
Publication |
Journal of archaeological science: reports |
Abbreviated Journal |
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Volume |
33 |
Issue |
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Pages |
102552 |
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Keywords |
C-N analysis Cryosolic soils geochemistry FTIR ICP-AES Inuit archaeology Nunavik Semi-subterranean house |
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Abstract |
Geochemical investigations using FTIR, ICP-AES and C-N analyses were carried out on a single-family semi-subterranean Inuit house in order to assess the contribution of Inuit domestic activities in the formation of cryosolic soils in a periglacial archaeological context (Kuuvik Bay, Nunavik, Canada). The geochemical elements data were analyzed using box plots and enrichment factors. The information was also summarized and visualized through principal component analysis (PCA). These complementary statistical approaches provided evidence of a moderate but identifiable and significant imprint of Inuit domestic activities on soil geochemistry. The box plots indicate moderate Ca, Mn, Cu and P enrichments and more noticeable Mg, Fe and S enrichments. These enrichment factors and the ICP-AES data show that samples from the peripheral wall and the tunnel entrance of the house and its vicinity are significantly enriched. While FTIR analysis highlighted the main soil element contents (e.g., organic and mineral components), ICP-AES analysis was used to further document variations in the background elements throughout the site. However, the obtained results do not allow us to undertake a spatial analysis of Inuit activities or to describe them in detail. In addition, the data highlight the difficulty of documenting the natural variability of element contents in cryosolic soils, especially in archaeological contexts. Cryo-pedological processes in the active layer as well as house cleaning and nutrient inputs resulting from Inuit occupations may have attenuated chemical signatures of previous Inuit domestic activities. |
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Programme |
1080 |
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Campaign |
LOTECHAIN |
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Address |
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Thesis |
Bachelor's thesis |
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Place of Publication |
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Series Issue |
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Edition |
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ISSN |
2352-409X |
ISBN |
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Notes |
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yes |
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Call Number |
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Serial |
8206 |
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Author |
Renac Christophe, Moine Bertrand, Goudour Jean-Pierre, LeRomancer Marc, Perrache Chantal |
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Title |
Stable isotope study of rainfall, river drainage and hot springs of the kerguelen archipelago, SW Indian Ocean |
Type |
Journal |
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Year |
2020 |
Publication |
Geothermics |
Abbreviated Journal |
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Volume |
83 |
Issue |
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Pages |
101726 |
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Keywords |
Geothermal springs Kerguelen archipelago Stable isotope composition Water-Rock interaction |
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Abstract |
This study is the first synthesis of chemical composition and stable isotopes values for the Kerguelen archipelago waters. The stable isotope values for rainfall and river waters in the Kerguelen archipelago allow a calculation of the Local Meteoric Water Line (δD rainfall = 8.43 x δ18O rainfall + 11) and a summer runoff line (δD river drainage = 7.45 x δ18O river drainage + 6). Surface waters with low- ion concentrations, chlorine facies and stable isotope values infiltrate through fractures and lava flows recharging deeper groundwaters. Thermal groundwater with low- (7 to 50 °C) and high- (50 to 100 °C) temperatures emerges in different localities in the volcanic archipelago. The low-temperature thermal waters might represent a mixture of high-temperature water with rainfall, thermal gradient changes or shallower infiltration compared to that for high-temperature thermal waters. The Rallier du Baty and Val Travers areas contain geothermal fluids with high-temperature springs, fumaroles and a large water flow. In the Rallier du Baty, the major ion chemistry and O, H, C and S stable isotope ratio of low (7 to 50 °C) temperature spring waters in Rallier du Baty area demonstrate a geothermal-system recharged by meteoric water (δD H2O liquid = 7.0 x δ18O H2O liquid + 0.5) rather than sea water. The chemical and isotopic compositions of elevated temperature spring waters (50 to 100 °C) have a long and complex history of meteoric water interacting with cooling magmas (δD H2O liquid = 1.78 x δ18O H2O liquid – 23). Surficial precipitation of aragonite, kaolinite, pyrite, native sulfur attest to a long livied geothermal system. A temperature of the geothermal reservoir has been estimated between 193 and 259 °C by cation geothermometry. The combination of minerals observed, major ion composition of water with thermodynamic modeling and stable isotope data suggest a geothermal system with a series of water/rock interactions from 50 to 250 °C. The conductive cooling of rising of H2O−CO2-rich fluids have produced a H2O−CO2 phase separation with the precipitation of secondary minerals. |
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Programme |
408,444 |
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Address |
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Corporate Author |
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Thesis |
Bachelor's thesis |
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Place of Publication |
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Summary Language |
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Original Title |
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ISSN |
0375-6505 |
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Notes |
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Approved |
yes |
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Call Number |
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Serial |
8262 |
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Author |
Alice Carravieri, Paco Bustamante, Pierre Labadie, Hélène Budzinski, Olivier Chastel, Yves Cherel |
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Title |
Trace elements and persistent organic pollutants in chicks of 13 seabird species from Antarctica to the subtropics |
Type |
Journal |
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Year |
2020 |
Publication |
Environment International |
Abbreviated Journal |
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Volume |
134 |
Issue |
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Pages |
105225 |
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Keywords |
Albatrosses; Mercury; Penguins; Petrels; Selenium; Stable isotopes |
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Abstract |
Seabirds from remote regions are mainly exposed to environmental contaminants from non-point contamination of their food webs. Pre-fledging seabird chicks are fed by their parents with marine prey captured in the vicinity of breeding colonies. Contaminant concentrations in tissues of pre-fledging chicks can thus be mostly related to local dietary sources, and have the potential to unravel spatial patterns of environmental contamination in marine ecosystems. Here, mercury (Hg), 13 other trace elements, and 18 persistent organic pollutants (POPs) were quantified in blood of chicks across four breeding locations that encompass a large latitudinal range in the southern Indian Ocean (from Antarctica, through subantarctic areas, to the subtropics), over a single breeding season. Thirteen species of penguins, albatrosses and petrels were studied, including endangered and near-threatened species, such as Amsterdam albatrosses and emperor penguins. Blood Hg burdens varied widely between species, with a factor of ~50 between the lowest and highest concentrations (mean ± SD, 0.05 ± 0.01 and 2.66 ± 0.81 µg g−1 dry weight, in thin-billed prions and Amsterdam albatrosses, respectively). Species relying on Antarctic waters for feeding had low Hg exposure. Concentrations of POPs were low in chicks, with the exception of hexachlorobenzene. Contaminant concentrations were mainly explained by species differences, but feeding habitat (inferred from δ13C values) and chicks’ body mass also contributed to explain variation. Collectively, our findings call for further toxicological investigations in Amsterdam albatrosses and small petrel species, because they were exposed to high and diverse sources of contaminants, and in macaroni penguins, which specifically showed very high selenium concentrations. Capsule Seabird chicks from four distant sites in the southern Indian Ocean had contrasted blood metallic and organic contaminant patterns depending on species, feeding habitat and body mass. |
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Programme |
109 |
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Thesis |
Bachelor's thesis |
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Place of Publication |
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Language |
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Summary Language |
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Original Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0160-4120 |
ISBN |
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Medium |
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Notes |
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Approved |
yes |
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Call Number |
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Serial |
7674 |
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Author |
Philip N. Trathan, Barbara Wienecke, Christophe Barbraud, Stéphanie Jenouvrier, Gerald Kooyman, Céline Le Bohec, David G. Ainley, André Ancel, Daniel P. Zitterbart, Steven L. Chown, Michelle LaRue, Robin Cristofari, Jane Younger, Gemma Clucas, Charles-André Bost, Jennifer A. Brown, Harriet J. Gillett, Peter T. Fretwell |
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Title |
The emperor penguin – Vulnerable to projected rates of warming and sea ice loss |
Type |
Journal |
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Year |
2020 |
Publication |
Biological Conservation |
Abbreviated Journal |
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Volume |
241 |
Issue |
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Pages |
108216 |
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Keywords |
Antarctic Climate change Conservation IUCN Red List threat status Protection |
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Abstract |
We argue the need to improve climate change forecasting for ecology, and importantly, how to relate long-term projections to conservation. As an example, we discuss the need for effective management of one species, the emperor penguin, Aptenodytes forsteri. This species is unique amongst birds in that its breeding habit is critically dependent upon seasonal fast ice. Here, we review its vulnerability to ongoing and projected climate change, given that sea ice is susceptible to changes in winds and temperatures. We consider published projections of future emperor penguin population status in response to changing environments. Furthermore, we evaluate the current IUCN Red List status for the species, and recommend that its status be changed to Vulnerable, based on different modelling projections of population decrease of ≥50% over the current century, and the specific traits of the species. We conclude that current conservation measures are inadequate to protect the species under future projected scenarios. Only a reduction in anthropogenic greenhouse gas emissions will reduce threats to the emperor penguin from altered wind regimes, rising temperatures and melting sea ice; until such time, other conservation actions are necessary, including increased spatial protection at breeding sites and foraging locations. The designation of large-scale marine spatial protection across its range would benefit the species, particularly in areas that have a high probability of becoming future climate change refugia. We also recommend that the emperor penguin is listed by the Antarctic Treaty as an Antarctic Specially Protected Species, with development of a species Action Plan. |
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Programme |
137,394 |
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Thesis |
Bachelor's thesis |
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Place of Publication |
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Summary Language |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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ISSN |
0006-3207 |
ISBN |
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Notes |
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Approved |
yes |
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Call Number |
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Serial |
7678 |
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| Permanent link to this record |
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Author |
Audrey Jaeger, Amandine Gamble, Erwan Lagadec, Camille Lebarbenchon, Vincent Bourret, Jérémy Tornos, Christophe Barbraud, Karin Lemberger, Karine Delord, Henri Weimerskirch, Jean-Baptiste Thiebot, Thierry Boulinier, Pablo Tortosa |
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Title |
Impact of Annual Bacterial Epizootics on Albatross Population on a Remote Island |
Type |
Journal |
| |
Year |
2020 |
Publication |
EcoHealth |
Abbreviated Journal |
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Volume |
17 |
Issue |
2 |
Pages |
194-202 |
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Keywords |
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Abstract |
The reduced species richness typical of oceanic islands provides an interesting environmental setup to examine in natura the epidemiological dynamics of infectious agents with potential implications for public health and/or conservation. On Amsterdam Island (Indian Ocean), recurrent die-offs of Indian yellow-nosed albatross (Thalassarche carteri) nestlings have been attributed to avian cholera, caused by the bacterium Pasteurella multocida. In order to help implementing efficient measures for the control of this disease, it is critical to better understand the local epidemiology of P. multocida and to examine its inter- and intra-annual infection dynamics. We evaluated the infection status of 264 yellow-nosed albatrosses over four successive breeding seasons using a real-time PCR targeting P. multocida DNA from cloacal swabs. Infection prevalence patterns revealed an intense circulation of P. multocida throughout the survey, with a steady but variable increase in infection prevalence within each breeding season. These epizootics were associated with massive nestling dies-offs, inducing very low fledging successes (≤ 20%). These results suggest important variations in the transmission dynamics of this pathogen. These findings and the developed PCR protocol have direct applications to guide future research and refine conservation plans aiming at controlling the disease. |
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Programme |
109, 1151 |
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Thesis |
Bachelor's thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1612-9210 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
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Approved |
yes |
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Call Number |
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Serial |
7961 |
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Author |
Lorène Julia Marchand, Michèle Tarayre, Thomas Dorey, Yann Rantier, Françoise Hennion |
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Title |
Morphological variability of cushion plant Lyallia kerguelensis (Caryophyllales) in relation to environmental conditions and geography in the Kerguelen Islands: implications for cushion necrosis and climate change |
Type |
Journal |
| |
Year |
2020 |
Publication |
Polar Biology |
Abbreviated Journal |
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Volume |
44 |
Issue |
1 |
Pages |
17-30 |
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Keywords |
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Abstract |
In recent decades, climate change has been faster in various parts of the world. Within species, to counter rapid climate changes shift of geographical area, individuals’ plastic responses or populations’ genetic adaptation might occur. The sub-Antarctic islands are subject to one of the most rapid climate changes on earth, with already visible impacts on native vegetation. Such might be the case of Lyallia kerguelensis a cushion plant strictly endemic to the Kerguelen Islands. In L. kerguelensis, necrotic parts were observed in cushions these last decades and possibly related to water stress. We analysed morphological variability of L. kerguelensis, including necrosis extent, across 19 populations spanning a wide range of environments across the Kerguelen Islands. Inter-population variations in the cushion surface area, shape and compactness were well explained by topography, degree of wind exposure, slope aspect, proportions of coarse sand and bare soil, and geographical distance between populations. All these variables are related to wind intensity and water availability. Moreover, in cushions with less than 10% necrosis in surface area, necrosis extent was positively correlated to soil sodium. Sodium availability might reduce the plant’s capacity for osmotic adjustment in face of other abiotic stresses, such as water stress. We conclude that cushion morphology may have the capacity to adjust to environmental variation, including aspects of climate change, but that cushion necrosis may be accelerated in the driest and most saline environments. |
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Programme |
1116 |
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Address |
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Corporate Author |
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Thesis |
Bachelor's thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1432-2056 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
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Approved |
yes |
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Call Number |
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Serial |
7793 |
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| Permanent link to this record |
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Author |
Guillaumot Charlène, Danis Bruno, Saucède Thomas |
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Title |
Selecting environmental descriptors is critical for modelling the distribution of Antarctic benthic species |
Type |
Journal |
| |
Year |
2020 |
Publication |
Polar Biology |
Abbreviated Journal |
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Volume |
43 |
Issue |
9 |
Pages |
1363-1381 |
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Keywords |
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Abstract |
Species distribution models (SDMs) are increasingly used in ecological and biogeographic studies by Antarctic biologists, including for conservation and management purposes. During the modelling process, model calibration is a critical step to ensure model reliability and robustness, especially in the case of SDMs, for which the number of selected environmental descriptors and their collinearity is a recurring issue. Boosted regression trees (BRT) was previously considered as one of the best modelling approach to correct for this type of bias. In the present study, we test the performance of BRT in modelling the distribution of Southern Ocean species using different numbers of environmental descriptors, either collinear or not. Models are generated for six sea star species with contrasting ecological niches and wide distribution ranges over the entire Southern Ocean. For the six studied species, overall modelling performance is not affected by the number of environmental descriptors used to generate models, BRT using the most informative descriptors and minimizing model overfitting. However, removing collinear descriptors also helps reduce model overfitting. Our results confirm that BRTs may perform well and are relevant to deal with complex and redundant environmental information for Antarctic biodiversity distribution studies. Selecting a limited number of non-collinear descriptors before modelling may generate simpler models and facilitate their interpretation. The modelled distributions do not differ noticeably between the different species despite contrasting species ecological niches. This unexpected result stresses important limitations in using SDMs for broad scale spatial studies, based on limited, spatially aggregated data, and low-resolution descriptors. |
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1044,1124 |
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Bachelor's thesis |
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1432-2056 |
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yes |
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8184 |
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