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	Author	Nolwenn Béhagle, Cédric Cotté, Anne Lebourges-Dhaussy, Gildas Roudaut, Guy Duhamel, Patrice Brehmer, Erwan Josse, Yves Cherel
	Title	Acoustic distribution of discriminated micronektonic organisms from a bi-frequency processing: The case study of eastern Kerguelen oceanic waters			Type	Journal
	Year	2017	Publication	Progress in Oceanography	Abbreviated Journal
	Volume	156	Issue		Pages	276-289
	Keywords	Acoustics Euphausiid Kerguelen Myctophid Southern Ocean
	Abstract	Despite its ecological importance, micronekton remains one of the least investigated components of the open-ocean ecosystems. Our main goal was to characterize micronektonic organisms using bi-frequency acoustic data (38 and 120kHz) by calibrating an algorithm tool that discriminates groups of scatterers in the top 300m of the productive oceanic zone east of Kerguelen Islands (Indian sector of the Southern Ocean). The bi-frequency algorithm was calibrated from acoustic properties of mono-specific biological samples collected with trawls, thus allowing to discriminate three acoustic groups of micronekton: (i) “gas-bearing” (ΔSv,120-38<−1dB), (ii) “fluid-like” (ΔSv,120-38>2dB), and (iii) “undetermined” scatterers (−1<ΔSv,120-38<2dB). The three groups likely correspond biologically to gas-filled swimbladder fish (myctophids), crustaceans (euphausiids and hyperiid amphipods), and other marine organisms potentially present in these waters and containing either lipid-filled or no inclusion (e.g. other myctophids), respectively. The Nautical Area Scattering Coefficient (NASC) was used (echo-integration cells of 10m long and 1m deep) between 30 and 300m depth as a proxy of relative biomass of acoustic targets. The distribution of NASC values showed a complex pattern according to: (i) the three acoustically-defined groups, (ii) the type of structures (patch vs. layers) and (iii) the timing of the day (day/night cycle). NASC values were higher at night than during the day. A large proportion of scatterers occurred in layers while patches, that mainly encompass gas-bearing organisms, are especially observed during daytime. This method provided an essential descriptive baseline of the spatial distribution of micronekton and a relevant approach to (i) link micronektonic group to physical parameters to define their habitats, (ii) investigate trophic interactions by combining active acoustic and top predator satellite tracking, and (iii) study the functioning of the pelagic ecosystems at various spatio-temporal scales.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0079-6611	ISBN	0079-6611	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7148
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	Author	Sara Labrousse, Jean-Baptiste Sallée, Alexander D. Fraser, Robert A. Massom, Phillip Reid, Michael Sumner, Christophe Guinet, Robert Harcourt, Clive McMahon, Frédéric Bailleul, Mark A. Hindell, Jean-Benoit Charrassin
	Title	Under the sea ice: Exploring the relationship between sea ice and the foraging behaviour of southern elephant seals in East Antarctica			Type	Journal
	Year	2017	Publication	Progress in Oceanography	Abbreviated Journal
	Volume	156	Issue		Pages	17-40
	Keywords
	Abstract	Investigating ecological relationships between predators and their environment is essential to understand the response of marine ecosystems to climate variability and change. This is particularly true in polar regions, where sea ice (a sensitive climate variable) plays a crucial yet highly dynamic and variable role in how it influences the whole marine ecosystem, from phytoplankton to top predators. For mesopredators such as seals, sea ice both supports a rich (under-ice) food resource, access to which depends on local to regional coverage and conditions. Here, we investigate sex-specific relationships between the foraging strategies of southern elephant seals (Mirounga leonina) in winter and spatio-temporal variability in sea ice concentration (SIC) and coverage in East Antarctica. We satellite-tracked 46 individuals undertaking post-moult trips in winter from Kerguelen Islands to the peri-Antarctic shelf between 2004 and 2014. These data indicate distinct general patterns of sea ice usage: while females tended to follow the sea ice edge as it extended northward, the males remained on the continental shelf despite increasing sea ice. Seal hunting time, a proxy of foraging activity inferred from the diving behaviour, was longer for females in late autumn in the outer part of the pack ice, ∼150–370km south of the ice edge. Within persistent regions of compact sea ice, females had a longer foraging activity (i) in the highest sea ice concentration at their position, but (ii) their foraging activity was longer when there were more patches of low concentration sea ice around their position (either in time or in space; 30days & 50km). The high spatio-temporal variability of sea ice around female positions is probably a key factor allowing them to exploit these concentrated patches. Despite lack of information on prey availability, females may exploit mesopelagic finfishes and squids that concentrate near the ice-water interface or within the water column (from diurnal vertical migration) in the pack ice region, likely attracted by an ice algal autumn bloom that sustains an under-ice ecosystem. In contrast, male foraging effort increased when they remained deep within the sea ice (420–960km from the ice edge) over the shelf. Males had a longer foraging activity (i) in the lowest sea ice concentration at their position, and (ii) when there were more patches of low concentration sea ice around their position (either in time or in space; 30days & 50km) presumably in polynyas or flaw leads between land fast and pack ice. This provides access to zones of enhanced resources in autumn or in early spring such as polynyas, the Antarctic shelf and slope. Our results suggest that some seals utilized a highly sea ice covered environment, which is key for their foraging effort, sustaining or concentrating resources during winter.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0079-6611	ISBN	0079-6611	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7167
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	Author	David Renault, Mathieu Laparie, Shannon J. McCauley, Dries Bonte
	Title	Environmental Adaptations, Ecological Filtering, and Dispersal Central to Insect Invasions			Type	Journal
	Year	2018	Publication	Annual review of entomology	Abbreviated Journal
	Volume	63	Issue	1	Pages	345-368
	Keywords
	Abstract	Insect invasions, the establishment and spread of nonnative insects in new regions, can have extensive economic and environmental consequences. Increased global connectivity accelerates rates of introductions, while climate change may decrease the barriers to invader species? spread. We follow an individual-level insect- and arachnid-centered perspective to assess how the process of invasion is influenced by phenotypic heterogeneity associated with dispersal and stress resistance, and their coupling, across the multiple steps of the invasion process. We also provide an overview and synthesis on the importance of environmental filters during the entire invasion process for the facilitation or inhibition of invasive insect population spread. Finally, we highlight important research gaps and the relevance and applicability of ongoing natural range expansions in the context of climate change to gain essential mechanistic insights into insect invasions.
	Programme	136
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0066-4170	ISBN	0066-4170	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6609
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	Author	Lucie Marandel, Philippe Gaudin, François Guéraud, Stéphane Glise, Alexandre Herman, Elisabeth Plagnes-Juan, Vincent Véron, Stéphane Panserat, Jacques Labonne
	Title	A reassessment of the carnivorous status of salmonids: Hepatic glucokinase is expressed in wild fish in Kerguelen Islands			Type	Journal
	Year	2017	Publication	Science of The Total Environment	Abbreviated Journal
	Volume	612	Issue		Pages	276-285
	Keywords	Carbohydrates Environment Gluconeogenesis Glucose metabolism Polar
	Abstract	Salmonids belong to a high trophic level and are thus considered as strictly carnivorous species, metabolically adapted for high catabolism of proteins and low utilisation of dietary carbohydrates. However they conserved a “mammalian-type” nutritional regulation of glucokinase encoding gene and its enzymatic activity by dietary carbohydrates which remains puzzling regarding their dietary regime. The present study investigates the hypothesis that this conservation could be linked to a real consumption by trout of this nutrient in their natural habitat. To do so, brown trout were sampled in the sub-Antarctic Kerguelen Islands, a site presenting oligotrophic hydrosystems and no local freshwater fish fauna prior the introduction of salmonids fifty years ago. Qualitative and quantitative analysis of carbohydrate content within Kerguelen trout stomachs demonstrate that these animals are fed on food resources containing digestible carbohydrates. Additionally, glycaemia and more particularly gck mRNA level and gck enzymatic activity prove that Kerguelen trout digest and metabolise dietary carbohydrates. Physiological and molecular analyses performed in the present study thus strongly evidence for consumption of dietary carbohydrates by wild trout in natural environments. Investigating differences between Kerguelen individuals, we found that smaller individuals presented higher glycaemia, as well as higher carbohydrates contents in stomach. However no relationship between scaled mass index and any physiological indicator was found. Thus it appears that Kerguelen trout do not turn to carbohydrate diet because of a different condition index, or that the consumption of carbohydrates does not lead to a generally degraded physiological status. As a conclusion, our findings may explain the evolutionary conservation of a “mammalian-type” nutritional regulation of gck by dietary carbohydrates in these carnivorous fish.
	Programme	1041
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697	ISBN	0048-9697	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6887
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	Author	Ika Djukic, Sebastian Kepfer-Rojas, Inger Kappel Schmidt, Klaus Steenberg Larsen, Claus Beier, Björn Berg, Kris Verheyen, Adriano Caliman, Alain Paquette, Alba Gutiérrez-Girón, Alberto Humber, Alejandro Valdecantos, Alessandro Petraglia, Heather Alexander, Algirdas Augustaitis, Amélie Saillard, Ana Carolina Ruiz Fernández, Ana I. Sousa, Ana I. Lillebø, Anderson da Rocha Gripp, André-Jean Francez, Andrea Fischer, Andreas Bohner, Andrey Malyshev, Andrijana Andrić, Andy Smith, Angela Stanisci, Anikó Seres, Anja Schmidt, Anna Avila, Anne Probst, Annie Ouin, Anzar A. Khuroo, Arne Verstraeten, Arely N. Palabral-Aguilera, Artur Stefanski, Aurora Gaxiola, Bart Muys, Bernard Bosman, Bernd Ahrends, Bill Parker, Birgit Sattler, Bo Yang, Bohdan Juráni, Brigitta Erschbamer, Carmen Eugenia Rodriguez Ortiz, Casper T. Christiansen, E. Carol Adair, Céline Meredieu, Cendrine Mony, Charles A. Nock, Chi-Ling Chen, Chiao-Ping Wang, Christel Baum, Christian Rixen, Christine Delire, Christophe Piscart, Christopher Andrews, Corinna Rebmann, Cristina Branquinho, Dana Polyanskaya, David Fuentes Delgado, Dirk Wundram, Diyaa Radeideh, Eduardo Ordóñez-Regil, Edward Crawford, Elena Preda, Elena Tropina, Elli Groner, Eric Lucot, Erzsébet Hornung, Esperança Gacia, Esther Lévesque, Evanilde Benedito, Evgeny A. Davydov, Evy Ampoorter, Fabio Padilha Bolzan, Felipe Varela, Ferdinand Kristöfel, Fernando T. Maestre, Florence Maunoury-Danger, Florian Hofhansl, Florian Kitz, Flurin Sutter, Francisco Cuesta, Francisco de Almeida Lobo, Franco Leandro de Souza, Frank Berninger, Franz Zehetner, Georg Wohlfahrt, George Vourlitis, Geovana Carreño-Rocabado, Gina Arena, Gisele Daiane Pinha, Grizelle González, Guylaine Canut, Hanna Lee, Hans Verbeeck, Harald Auge, Harald Pauli, Hassan Bismarck Nacro, Héctor A. Bahamonde, Heike Feldhaar, Heinke Jäger, Helena C. Serrano, Hélène Verheyden, Helge Bruelheide, Henning Meesenburg, Hermann Jungkunst, Hervé Jactel, Hideaki Shibata, Hiroko Kurokawa, Hugo López Rosas, Hugo L. Rojas Villalobos, Ian Yesilonis, Inara Melece, Inge Van Halder, Inmaculada García Quirós, Isaac Makelele, Issaka Senou, István Fekete, Ivan Mihal, Ivika Ostonen, Jana Borovská, Javier Roales, Jawad Shoqeir, Jean-Christophe Lata, Jean-Paul Theurillat, Jean-Luc Probst, Jess Zimmerman, Jeyanny Vijayanathan, Jianwu Tang, Jill Thompson, Jiří Doležal, Joan-Albert Sanchez-Cabeza, Joël Merlet, Joh Henschel, Johan Neirynck, Johannes Knops, John Loehr, Jonathan von Oppen, Jónína Sigríður Þorláksdóttir, Jörg Löffler, José-Gilberto Cardoso-Mohedano, José-Luis Benito-Alonso, Jose Marcelo Torezan, Joseph C. Morina, Juan J. Jiménez, Juan Dario Quinde, Juha Alatalo, Julia Seeber, Jutta Stadler, Kaie Kriiska, Kalifa Coulibaly, Karibu Fukuzawa, Katalin Szlavecz, Katarína Gerhátová, Kate Lajtha, Kathrin Käppeler, Katie A. Jennings, Katja Tielbörger, Kazuhiko Hoshizaki, Ken Green, Lambiénou Yé, Laryssa Helena Ribeiro Pazianoto, Laura Dienstbach, Laura Williams, Laura Yahdjian, Laurel M. Brigham, Liesbeth van den Brink, Lindsey Rustad, Lipeng Zhang, Lourdes Morillas, Lu Xiankai, Luciana Silva Carneiro, Luciano Di Martino, Luis Villar, Maaike Y. Bader, Madison Morley, Marc Lebouvier, Marcello Tomaselli, Marcelo Sternberg, Marcus Schaub, Margarida Santos-Reis, Maria Glushkova, María Guadalupe Almazán Torres, Marie-Andrée Giroux, Marie-Anne de Graaff, Marie-Noëlle Pons, Marijn Bauters, Marina Mazón, Mark Frenzel, Markus Didion, Markus Wagner, Maroof Hamid, Marta L. Lopes, Martha Apple, Martin Schädler, Martin Weih, Matteo Gualmini, Matthew A. Vadeboncoeur, Michael Bierbaumer, Michael Danger, Michael Liddell, Michael Mirtl, Michael Scherer-Lorenzen, Michal Růžek, Michele Carbognani, Michele Di Musciano, Michinari Matsushita, Miglena Zhiyanski, Mihai Pușcaș, Milan Barna, Mioko Ataka, Mo Jiangming, Mohammed Alsafran, Monique Carnol, Nadia Barsoum, Naoko Tokuchi, Nico Eisenhauer, Nicolas Lecomte, Nina Filippova, Norbert Hölzel, Olga Ferlian, Oscar Romero, Osvaldo B. Pinto, Pablo Peri, Paige Weber, Pascal Vittoz, Pavel Dan Turtureanu, Peter Fleischer, Peter Macreadie, Peter Haase, Peter Reich, Petr Petřík, Philippe Choler, Pierre Marmonier, Priscilla Muriel, Quentin Ponette, Rafael Dettogni Guariento, Rafaella Canessa, Ralf Kiese, Rebecca Hewitt, Regin Rønn, Rita Adrian, Róbert Kanka, Robert Weigel, Roberto Cazzolla Gatti, Rodrigo Lemes Martins, Romain Georges, Rosa Isela Meneses, Rosario G. Gavilán, Sabyasachi Dasgupta, Sally Wittlinger, Sara Puijalon, Sarah Freda, Satoshi Suzuki, Sean Charles, Sébastien Gogo, Simon Drollinger, Simone Mereu, Sonja Wipf, Stacey Trevathan-Tackett, Stefan Löfgren, Stefan Stoll, Stefan Trogisch, Stefanie Hoeber, Steffen Seitz, Stephan Glatzel, Sue J. Milton, Sylvie Dousset, Taiki Mori, Takanori Sato, Takeshi Ise, Takuo Hishi, Tanaka Kenta, Tatsuro Nakaji, Thaisa Sala Michelan, Thierry Camboulive, Thomas J. Mozdzer, Thomas Scholten, Thomas Spiegelberger, Thomas Zechmeister, Till Kleinebecker, Tsutom Hiura, Tsutomu Enoki, Tudor-Mihai Ursu, Umberto Morra di Cella, Ute Hamer, Valentin H. Klaus, Vanessa Mendes Rêgo, Valter Di Cecco, Verena Busch, Veronika Fontana, Veronika Piscová, Victoria Carbonell, Victoria Ochoa, Vincent Bretagnolle, Vincent Maire, Vinicius Farjalla, Wenjun Zhou, Wentao Luo, William H. McDowell, Yalin Hu, Yasuhiro Utsumi, Yuji Kominami, Yulia Zaika, Yury Rozhkov, Zsolt Kotroczó, Zsolt Tóth
	Title	Early stage litter decomposition across biomes			Type	Journal
	Year	2018	Publication	Science of the total environment	Abbreviated Journal
	Volume	628-629	Issue		Pages	1369-1394
	Keywords	Carbon turnover Green tea Rooibos tea Tea bag TeaComposition initiative
	Abstract	Through litter decomposition enormous amounts of carbon is emitted to the atmosphere. Numerous large-scale decomposition experiments have been conducted focusing on this fundamental soil process in order to understand the controls on the terrestrial carbon transfer to the atmosphere. However, previous studies were mostly based on site-specific litter and methodologies, adding major uncertainty to syntheses, comparisons and meta-analyses across different experiments and sites. In the TeaComposition initiative, the potential litter decomposition is investigated by using standardized substrates (Rooibos and Green tea) for comparison of litter mass loss at 336 sites (ranging from −9 to +26 °C MAT and from 60 to 3113 mm MAP) across different ecosystems. In this study we tested the effect of climate (temperature and moisture), litter type and land-use on early stage decomposition (3 months) across nine biomes. We show that litter quality was the predominant controlling factor in early stage litter decomposition, which explained about 65% of the variability in litter decomposition at a global scale. The effect of climate, on the other hand, was not litter specific and explained <0.5% of the variation for Green tea and 5% for Rooibos tea, and was of significance only under unfavorable decomposition conditions (i.e. xeric versus mesic environments). When the data were aggregated at the biome scale, climate played a significant role on decomposition of both litter types (explaining 64% of the variation for Green tea and 72% for Rooibos tea). No significant effect of land-use on early stage litter decomposition was noted within the temperate biome. Our results indicate that multiple drivers are affecting early stage litter mass loss with litter quality being dominant. In order to be able to quantify the relative importance of the different drivers over time, long-term studies combined with experimental trials are needed.
	Programme	136
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697	ISBN	0048-9697	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7018
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	Author	A. Goutte, A. Meillère, C. Barbraud, H. Budzinski, P. Labadie, L. Peluhet, H. Weimerskirch, K. Delord, O. Chastel
	Title	Demographic, endocrine and behavioral responses to mirex in the South polar skua			Type	Journal
	Year	2018	Publication	Science of The Total Environment	Abbreviated Journal
	Volume	631-632	Issue		Pages	317-325
	Keywords	Capture–mark–recapture Ecotoxicology Population dynamics Vital rates
	Abstract	Population consequences of chronic exposure to multiple pollutants at low environmental doses remain speculative, because of the lack of appropriate long-term monitoring surveys. This study integrates proximate and ultimate aspects of persistent organic pollutants (POP) burden in free-living vertebrates, by coupling hormonal and behavioral endpoints, life-history traits, and population dynamics. Blood samples (N=70) were collected in South polar skuas during two breeding periods, in 2003 and 2005, and individuals were annually monitored until 2011. Multi-state mark recapture models were used to test the effects of POP levels on demographic traits. Survival rate and long-term breeding probability were not related to individual POP levels, whereas long-term breeding success significantly decreased with increasing blood levels of mirex, an organochlorine insecticide. At the proximate level, corticosterone (stress hormone) and prolactin (parental care hormone) levels were not linked to individual POP burden. Nest defense in 2005 was significantly less intensive in chick-rearing skuas bearing higher mirex levels, suggesting reproductive behavioral impairment. Matrix population models were then built to project the rate of population decline according to increasing mirex burden. Although mirex levels were 2.8 times higher in 2003 than in 2005, the population-level effect of mirex was only detected in 2005, the year of higher corticosterone levels. The combination of endocrine traits with demographic analysis thereby enables to provide new support of synergistic interactions between pollutants and stress levels on long-term breeding outputs and population dynamics.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0048-9697	ISBN	0048-9697	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7119
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	Author	F. Thibon, L. Weppe, N. Vigier, C. Churlaud, T. Lacoue-Labarthe, M. Metian, Y. Cherel, P. Bustamante
	Title	Large-scale survey of lithium concentrations in marine organisms			Type	Journal
	Year	2021	Publication	Science of The Total Environment	Abbreviated Journal
	Volume	751	Issue		Pages	141453
	Keywords	Bio-reduction Bioaccumulation Biogeography Ecotoxicology Multiple correspondence analyses Trophic webs
	Abstract	Trace metals such as Cu, Hg, and Zn have been widely investigated in marine ecotoxicological studies considering their bioaccumulation, transfer along trophic webs, and the risks they pose to ecosystems and human health. Comparatively, Li has received little attention, although this element is increasingly used in the high-tech, ceramics/glass, and medication industries. Here, we report Li concentrations in more than 400 samples, including whole organisms and different organs of bivalves, cephalopods, crustaceans, and fish. We investigated species from three contrasting biogeographic areas, i.e. temperate (Bay of Biscay, northeast Atlantic Ocean), tropical (New Caledonia, Pacific Ocean), and subpolar climates (Kerguelen Islands, southern Indian Ocean), among diverse trophic groups (filter-feeders to meso-predators) and habitats (benthic, demersal, and pelagic). Although Li is homogeneously distributed in the ocean (at 0.18 μg/mL), Li concentrations in soft tissues vary greatly, from 0.01 to 1.20 μg/g dry weight. Multiple correspondence analyses reveal two clusters of high and low Li concentrations. Li distributions in marine organisms appear to be mostly geographically independent, though our results highlight a temperature dependency in fish muscles. Li is consistently bio-reduced through the trophic webs, with filter-feeders showing the highest concentrations and predatory fish the lowest. Strong variations are observed among organs, consistent with the biochemical similarity between Na and Li during transport in the brain and in osmoregulatory organs. Fish gills and kidneys show relatively high Li concentrations (0.26 and 0.15 μg/g, respectively) and fish brains show a large range of Li contents (up to 0.34 μg/g), whereas fish liver and muscles are Li depleted (0.07 ± 0.03 and 0.06 ± 0.08 μg/g, respectively). Altogether, these results provide the first exhaustive baseline for future Li ecotoxicology studies in marine coastal environments.
	Programme	109
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN	0048-9697	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7944
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	Author	R. Traversi, S. Becagli, M. Brogioni, L. Caiazzo, V. Ciardini, F. Giardi, M. Legrand, G. Macelloni, B. Petkov, S. Preunkert, C. Scarchilli, M. Severi, V. Vitale, R. Udisti
	Title	Multi-year record of atmospheric and snow surface nitrate in the central Antarctic plateau			Type	Journal
	Year	2017	Publication	Chemosphere	Abbreviated Journal
	Volume	172	Issue		Pages	341-354
	Keywords	Aerosol Antarctica Dome C Nitrate Stratosphere-troposphere exchange Surface snow
	Abstract	Continuous all year-round samplings of atmospheric aerosol and surface snow at high (daily to 4-day) resolution were carried out at Dome C since 2004-05 to 2013 and nitrate records are here presented. Basing on a larger statistical data set than previous studies, results confirm that nitrate seasonal pattern is characterized by maxima during austral summer for both aerosol and surface snow, occurring in-phase with solar UV irradiance. This temporal pattern is likely due to a combination of nitrate sources and post-depositional processes whose intensity usually enhances during the summer. Moreover, it should be noted that a case study of the synoptic conditions, which took place during a major nitrate event, showed the occurrence of a stratosphere-troposphere exchange. The sampling of both matrices at the same time with high resolution allowed the detection of a an about one-month long recurring lag of summer maxima in snow with respect to aerosol. This result can be explained by deposition and post-deposition processes occurring at the atmosphere-snow interface, such as a net uptake of gaseous nitric acid and a replenishment of the uppermost surface layers driven by a larger temperature gradient in summer. This hypothesis was preliminarily tested by a comparison with surface layers temperature data in the 2012-13 period. The analysis of the relationship between the nitrate concentration in the gas phase and total nitrate obtained at Dome C (2012-13) showed the major role of gaseous HNO3 to the total nitrate budget suggesting the need to further investigate the gas-to-particle conversion processes.
	Programme	414
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	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0045-6535	ISBN	0045-6535	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6671
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	Author	Andrea Spolaor, Hélène Angot, Marco Roman, Aurélien Dommergue, Claudio Scarchilli, Massimiliano Vardè, Massimo Del Guasta, Xanthi Pedeli, Cristiano Varin, Francesca Sprovieri, Olivier Magand, Michel Legrand, Carlo Barbante, Warren R. L. Cairns
	Title	Feedback mechanisms between snow and atmospheric mercury: Results and observations from field campaigns on the Antarctic plateau			Type	Journal
	Year	2018	Publication	Chemosphere	Abbreviated Journal
	Volume	197	Issue		Pages	306-317
	Keywords	Antarctica Dome C Halogens Mercury Precipitation Snow
	Abstract	The Antarctic Plateau snowpack is an important environment for the mercury geochemical cycle. We have extensively characterized and compared the changes in surface snow and atmospheric mercury concentrations that occur at Dome C. Three summer sampling campaigns were conducted between 2013 and 2016. The three campaigns had different meteorological conditions that significantly affected mercury deposition processes and its abundance in surface snow. In the absence of snow deposition events, the surface mercury concentration remained stable with narrow oscillations, while an increase in precipitation results in a higher mercury variability. The Hg concentrations detected confirm that snowfall can act as a mercury atmospheric scavenger. A high temporal resolution sampling experiment showed that surface concentration changes are connected with the diurnal solar radiation cycle. Mercury in surface snow is highly dynamic and it could decrease by up to 90% within 4/6 h. A negative relationship between surface snow mercury and atmospheric concentrations has been detected suggesting a mutual dynamic exchange between these two environments. Mercury concentrations were also compared with the Br concentrations in surface and deeper snow, results suggest that Br could have an active role in Hg deposition, particularly when air masses are from coastal areas. This research presents new information on the presence of Hg in surface and deeper snow layers, improving our understanding of atmospheric Hg deposition to the snow surface and the possible role of re-emission on the atmospheric Hg concentration.
	Programme	414,1028
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	Corporate Author				Thesis	Bachelor's thesis
	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0045-6535	ISBN	0045-6535	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	7229
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	Author	Niels M. Schmidt, Bess Hardwick, Olivier Gilg, Toke T. Høye, Paul Henning Krogh, Hans Meltofte, Anders Michelsen, Jesper B. Mosbacher, Katrine Raundrup, Jeroen Reneerkens, Lærke Stewart, Helena Wirta, Tomas Roslin
	Title	Interaction webs in arctic ecosystems: Determinants of arctic change?			Type	Journal
	Year	2017	Publication	Ambio	Abbreviated Journal
	Volume	46	Issue	1	Pages	12-25
	Keywords
	Abstract	How species interact modulate their dynamics, their response to environmental change, and ultimately the functioning and stability of entire communities. Work conducted at Zackenberg, Northeast Greenland, has changed our view on how networks of arctic biotic interactions are structured, how they vary in time, and how they are changing with current environmental change: firstly, the high arctic interaction webs are much more complex than previously envisaged, and with a structure mainly dictated by its arthropod component. Secondly, the dynamics of species within these webs reflect changes in environmental conditions. Thirdly, biotic interactions within a trophic level may affect other trophic levels, in some cases ultimately affecting land–atmosphere feedbacks. Finally, differential responses to environmental change may decouple interacting species. These insights form Zackenberg emphasize that the combination of long-term, ecosystem-based monitoring, and targeted research projects offers the most fruitful basis for understanding and predicting the future of arctic ecosystems.
	Programme	1036
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	Publisher		Place of Publication		Editor
	Language		Summary Language		Original Title
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0044-7447, 1654-7209	ISBN	0044-7447, 1654-7209	Medium
	Area		Expedition		Conference
	Notes				Approved	yes
	Call Number				Serial	6961
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