| Records |
| Author |
Moreau Camille, Saucède Thomas, Jossart Quentin, Agüera Antonio, Brayard Arnaud, Danis Bruno |
| Title |
Reproductive strategy as a piece of the biogeographic puzzle: a case study using Antarctic sea stars (Echinodermata, Asteroidea) |
Type |
Journal |
| Year |
2017 |
Publication |
Journal of Biogeography |
Abbreviated Journal |
|
| Volume |
44 |
Issue |
4 |
Pages |
848-860 |
| Keywords |
Antarctica benthos biogeographic barrier Echinodermata invertebrate regionalization reproductive mode sea stars Southern Ocean |
| Abstract |
Abstract Aim To describe and analyse asteroid biogeographic patterns in the Southern Ocean (SO) and test whether reproductive strategy (brooder versus broadcaster) can explain distribution patterns at the scale of the entire class. We hypothesize that brooding and broadcasting species display different biogeographic patterns. Location Southern Ocean, south of 45 °S. Methods Over 14,000 asteroid occurrences are analysed using bootstrapped spanning network (BSN), non?metrical multidimensional scaling (nMDS) and clustering to uncover the spatial structure of faunal similarities among 25 bioregions. Results Main biogeographic patterns are congruent with previous works based on other taxa and highlight the isolation of New Zealand, the high richness in the Scotia Arc area particularly of brooding species, an East/West Antarctic differentiation, and the faunal affinities between South America and sub?Antarctic Islands. Asteroids show lower endemism levels than previously reported with 29% of species occurring in Antarctica only. In particular, asteroids from Tierra del Fuego showed affinities with those of West Antarctica at the species level, suggesting a recent mixing of assemblages. Biogeographic patterns are highly linked to reproductive strategy. Patterns also differ according to the taxonomic level, revealing the underlying role of historical factors. Main conclusions Patterns of sea star biogeography are consistent with results obtained for other marine groups and are strongly linked to reproductive strategy. |
| Programme |
1044 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
|
Edition |
|
| ISSN |
0305-0270 |
ISBN  |
0305-0270 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
6690 |
| Permanent link to this record |
| |
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| |
| Author |
Lehnebach Carlos A., Winkworth Richard C., Becker Matthias, Lockhart Peter J., Hennion Françoise |
| Title |
Around the pole: evolution of sub‐Antarctic Ranunculus |
Type |
Journal |
| Year |
2017 |
Publication |
Journal of Biogeography |
Abbreviated Journal |
|
| Volume |
44 |
Issue |
4 |
Pages |
875-886 |
| Keywords |
dispersal divergence time estimates ecomorphology historical biogeography phylogenetic biogeography Ranunculus sub‐Antarctic islands |
| Abstract |
Abstract Aim Despite an improved understanding of Southern Hemisphere plant biogeography, the origins and evolution of sub?Antarctic floras remain poorly studied. Here, we investigate the historical biogeography of sub?Antarctic representatives of the genus Ranunculus. We aimed to establish when and from where the sub?Antarctic ranunculi originated as well as to examine the extent to which ecomorphological traits explain contemporary biogeographical patterns. Location Southern temperate and sub?Antarctic zones. Methods We first estimated a dated phylogeny for Ranunculus using combined chloroplast and nuclear data for 53 accessions; divergence times were inferred based on three temporal calibrations. We then used non?parametric multidimensional scaling to evaluate the ecomorphological diversity of 67 austral ranunculi representing a combination of sub?Antarctic species and those restricted to lower latitude landmasses. Results Phylogenetic analyses indicated that several Ranunculus lineages have colonized the sub?Antarctic islands. Divergence time estimates suggest recent arrival from source areas in Australia, New Zealand or South America. Species exhibiting two distinct ecomorphological trait combinations occur in both sub?Antarctic and lower latitude habitats; the proportions of each combination differed significantly between these areas. Main conclusions Ranunculus has colonized the sub?Antarctic on several occasions, most often arriving from the lower latitude landmasses prior to the Last Glacial Maximum. Taken together our analyses suggest that chance effects are likely to have influenced species arrival. However, following arrival trait?environment interactions appear to have been important for the subsequent establishment and persistence of ranunculi in sub?Antarctic habitats. |
| Programme |
136,1116 |
| Campaign |
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| Address |
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| Corporate Author |
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Thesis |
Bachelor's thesis |
| 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 |
|
| ISSN |
0305-0270 |
ISBN |
0305-0270 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
6734 |
| Permanent link to this record |
| |
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| |
| Author |
É. Bernard, J. M. Friedt, A. Saintenoy, F. Tolle, M. Griselin, C. Marlin |
| Title |
Where does a glacier end? GPR measurements to identify the limits between valley slopes and actual glacier body. Application to the Austre Lovénbreen, Spitsbergen |
Type |
Journal |
| Year |
2014 |
Publication |
International Journal of Applied Earth Observation and Geoinformation |
Abbreviated Journal |
|
| Volume |
27 |
Issue |
|
Pages |
100-108 |
| Keywords |
Arctic Glacier limit Ground penetrating Radar Polar glacier Spitsbergen |
| Abstract |
Glacier limits are usually mapped according to a spatial discrimination based on color of remote sensing images or aerial photography. What appears like ice (white or light colored areas) at the end of the ablation period (end of summer) corresponds to the glacier, while what appears as rock (dark areas) is identified as the slope. This kind of visual discretization seems to be insufficient in the case of small arctic glaciers. Indeed, the slopes have been described as very unstable parts of glacial basins. Debris are generated by the inclination of the slopes, and reach the glacier surface. Thus, the visible limit does not correspond to the ice extension: a significant amount of ice is potentially covered by rock debris, enlarging the actual glacier surface with respect to the observed area. Hence, we apply Ground Penetrating Radar (GPR) measurements for mapping, beyond the central parts of the glacier, the steep slopes of the Austre Lovénbreen (Spitsbergen, 79° N). The aim is to assess the discrepancy between the limits extracted from remote sensing methods – aerial photography, satellite images and derived digital elevation models – and the GPR data which exhibit significant ice thickness at locations considered outside the glacier itself. The ice is observed to extend typically from 25 to 30m, and up to 100m, under the slopes. These measurements allow for a new determination of the rock/ice interface location following criteria beyond the visual and morphological characteristics seen from the surface, as obtained by remote sensing techniques or in-situ observations. |
| Programme |
1108 |
| Campaign |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0303-2434 |
ISBN |
0303-2434 |
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
629 |
| Permanent link to this record |
| |
|
| |
| Author |
Karl Ljung, Sofia Holmgren, Malin Kylander, Jesper Sjolte, Nathalie Van der Putten, Masa Kageyama, Charles T. Porter, Svante Björck |
| Title |
The last termination in the central South Atlantic |
Type |
Journal |
| Year |
2015 |
Publication |
Quaternary Science Reviews |
Abbreviated Journal |
|
| Volume |
123 |
Issue |
|
Pages |
193-214 |
| Keywords |
Bipolar see-saw climate pattern Last termination Model simulation Multiproxy study South Atlantic Southern hemisphere zonal circulation Subtropical front Tristan da Cunha |
| Abstract |
Lake sediments and peat deposits from two basins on Nightingale Island (37°S), in the Tristan da Cunha archipelago, South Atlantic, have been analyzed. The studies were focused on the time period 16.2–10.0 cal ka BP, determined by 36 14C dates from the two sequences. A wide variety of proxies were used, including pollen and diatom analyzes, biogenic silica content, C and N analyzes, stable isotopes (13C and 15N), elemental concentrations and magnetic susceptibility measurements, to detect environmental changes that can be related to shifts of the circulation belts of the Southern Ocean. In addition, climate model simulations were carried out. We find that the sediments are underlain by a >2 cal ka BP long hiatus, possibly representing a dried-out lake bed. The climate simulations corroborate that the area might have been exposed to arid conditions as a consequence of the Heinrich 1 event in the north and a southward displacement of the ITCZ. The development on the island after 16.2 cal ka BP is determined by the position of the Subtropical Front (STF) and the Southern Hemisphere Westerlies (SHW). The period 16.2–14.75 cal ka BP was characterized by varying influence from SHW and with STF situated south of Tristan da Cunha, ending with a humidity peak and cooler conditions. The stable conditions 14.7–14.1 cal ka BP with cool and fairly arid conditions imply that STF and SHW were both north of the islands during the first part of the Antarctic Cold Reversal. The most unstable period, 14.1–12.7 cal ka BP, indicates incessant latitudinal shifts of the zonal circulation, perhaps related to climate variability in the Northern Hemisphere and bipolar seesaw mechanisms as the strength of the Atlantic Meridional Overturning Circulation (AMOC) varied. At 12.7 cal ka BP the Holocene warming began with a gradually drier and warmer climate as a result of a dampened AMOC during the Younger Dryas cooling in the north with ITCZ, STF and SHW being displaced southwards. Peak warming seems to have occurred in the earliest part of the Holocene, but this period was also characterized by humidity shifts, possibly an effect of retraction and expansion phases of SHW during AMOC variations in the north. |
| Programme |
1133 |
| Campaign |
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| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
Summary Language |
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Original Title |
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| Series Editor |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0277-3791 |
ISBN |
0277-3791 |
Medium |
|
| Area |
|
Expedition |
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Conference |
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| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7207 |
| Permanent link to this record |
| |
|
| |
| Author |
Biancamaria Narcisi, Jean Robert Petit, Barbara Delmonte, Valentina Batanova, Joël Savarino |
| Title |
Multiple sources for tephra from AD 1259 volcanic signal in Antarctic ice cores |
Type |
Journal |
| Year |
2019 |
Publication |
Quaternary Science Reviews |
Abbreviated Journal |
|
| Volume |
210 |
Issue |
|
Pages |
164-174 |
| Keywords |
Antarctic rifting volcanism Antarctica Cryptotephra Glass shard microanalysis Ice cores Samalas AD 1257 eruption Volcanic isochron |
| Abstract |
Strong volcanic signals simultaneously recorded in polar ice sheets are commonly assigned to major low-latitude eruptions that dispersed large quantities of aerosols in the global atmosphere with the potential of inducing climate perturbations. Parent eruptions responsible for specific events are typically deduced from matching to a known volcanic eruption having coincidental date. However, more robust source linkage can be achieved only through geochemical characterisation of the airborne volcanic glass products (tephra) sometimes preserved in the polar strata. We analysed fine-grained tephra particles extracted from layers of the AD 1259 major bipolar volcanic signal in four East Antarctic ice cores drilled in different widely-spaced locations on the Antarctic Plateau. The very large database of glass-shard geochemistry combined with grain size analyses consistently indicate that the material was sourced from multiple distinct eruptions. These are the AD 1257 mega-eruption of Samalas volcano in Indonesia, recently proposed to be the single event responsible for the polar signal, as well as a newly-identified Antarctic eruption, which occurred in northern Victoria Land in AD 1259. Finally, a further eruption that took place somewhere outside of Antarctica has also contributed to tephra deposition. Our high-resolution, multiple-site approach was critical for revealing spatial heterogeneity of tephra at the continental scale. Evidence from ice-core tephra indicates recurrent explosive activity at the Antarctic volcanoes and could have implications for improved reconstruction of post-volcanic effects on climate from proxy polar records. |
| Programme |
1177 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
|
Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0277-3791 |
ISBN |
0277-3791 |
Medium |
|
| Area |
|
Expedition |
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Conference |
|
| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7496 |
| Permanent link to this record |
| |
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| |
| Author |
Sophie Montuire, Aurélien Royer, Anna Lemanik, Olivier Gilg, Natalya Sokolova, Aleksandr Sokolov, Emmanuel Desclaux, Adam Nadachowski, Nicolas Navarro |
| Title |
Molar shape differentiation during range expansions of the collared lemming (Dicrostonyx torquatus) related to past climate changes |
Type |
Journal |
| Year |
2019 |
Publication |
Quaternary Science Reviews |
Abbreviated Journal |
|
| Volume |
221 |
Issue |
|
Pages |
105886 |
| Keywords |
Climate Collared lemmings Geometric morphometrics Range expansion |
| Abstract |
The genus Dicrostonyx (the collared lemming) is undoubtedly the small mammal best adapted to the extreme conditions of the arctic environment. The Palearctic collared lemming has been described in numerous European Late Pleistocene localities up to south of France and Croatia. This species experienced climate-driven changes through time, changes mainly observed as repetitive pulses of pan-continental migration, and it thus became a typical indicator of glacial conditions. Using geometric morphometrics on molars, we evaluate the shape changes occurring during the last 100 ky over some dispersal events in Western Europe. The results point out that Dicrostonyx torquatus has a large intra-population variation with a homogenous morphology, regardless of the origin of the individuals. A temporal trend leading to a more complex tooth with a differentiated anterior loop on the first lower molar was observed. An additional effect of the distance from the core populations was also described with a more peculiar shape for the most western populations of France. These temporal and geographical trends might relate to the different migratory pulses documented from ancient DNA haplotypes. |
| Programme |
1036 |
| Campaign |
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| Address |
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| Corporate Author |
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Thesis |
Bachelor's thesis |
| Publisher |
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Place of Publication |
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Editor |
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| Language |
|
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 |
0277-3791 |
ISBN |
0277-3791 |
Medium |
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| Area |
|
Expedition |
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Conference |
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| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
7614 |
| Permanent link to this record |
| |
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| |
| Author |
A. Ghelfi, D. Maurin, A. Cheminet, L. Derome, G. Hubert, F. Melot |
| Title |
Neutron monitors and muon detectors for solar modulation studies: 2. ϕ time series |
Type |
Journal |
| Year |
2017 |
Publication |
Advances in Space Research |
Abbreviated Journal |
|
| Volume |
60 |
Issue |
4 |
Pages |
833-847 |
| Keywords |
Cosmic rays Muon detector Neutron monitor Solar modulation |
| Abstract |
The level of solar modulation at different times (related to the solar activity) is a central question of solar and galactic cosmic-ray physics. In the first paper of this series, we have established a correspondence between the uncertainties on ground-based detectors count rates and the parameter ϕ (modulation level in the force-field approximation) reconstructed from these count rates. In this second paper, we detail a procedure to obtain a reference ϕ time series from neutron monitor data. We show that we can have an unbiased and accurate ϕ reconstruction (Δϕ/ϕ≃10%). We also discuss the potential of Bonner spheres spectrometers and muon detectors to provide ϕ time series. Two by-products of this calculation are updated ϕ values for the cosmic-ray database and a web interface to retrieve and plot ϕ from the 50’s to today (http://lpsc.in2p3.fr/crdb). |
| Programme |
1112 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
0273-1177 |
ISBN |
0273-1177 |
Medium |
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| Area |
|
Expedition |
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Conference |
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| Notes |
|
Approved |
yes |
| Call Number |
|
Serial |
6724 |
| Permanent link to this record |
| |
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| |
| Author |
A. Ghelfi, D. Maurin, A. Cheminet, L. Derome, G. Hubert, F. Melot |
| Title |
Neutron monitors and muon detectors for solar modulation studies: 2. ϕ time series |
Type |
Journal |
| Year |
2017 |
Publication |
Advances in Space Research |
Abbreviated Journal |
|
| Volume |
60 |
Issue |
4 |
Pages |
833-847 |
| Keywords |
Cosmic rays Muon detector Neutron monitor Solar modulation |
| Abstract |
The level of solar modulation at different times (related to the solar activity) is a central question of solar and galactic cosmic-ray physics. In the first paper of this series, we have established a correspondence between the uncertainties on ground-based detectors count rates and the parameter ϕ (modulation level in the force-field approximation) reconstructed from these count rates. In this second paper, we detail a procedure to obtain a reference ϕ time series from neutron monitor data. We show that we can have an unbiased and accurate ϕ reconstruction (Δϕ/ϕ≃10%). We also discuss the potential of Bonner spheres spectrometers and muon detectors to provide ϕ time series. Two by-products of this calculation are updated ϕ values for the cosmic-ray database and a web interface to retrieve and plot ϕ from the 50’s to today (http://lpsc.in2p3.fr/crdb). |
| Programme |
1112 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
0273-1177 |
ISBN |
0273-1177 |
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 |
| Call Number |
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Serial |
7036 |
| Permanent link to this record |
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| |
| Author |
Bruno-Charles Busseau, Alain Royer, Alexandre Roy, Alexandre Langlois, Florent Domine |
| Title |
Analysis of snow-vegetation interactions in the low Arctic-Subarctic transition zone (northeastern Canada) |
Type |
Journal |
| Year |
2017 |
Publication |
Physical Geography |
Abbreviated Journal |
|
| Volume |
38 |
Issue |
2 |
Pages |
159-175 |
| Keywords |
Normalized Difference Snow Index north-eastern Canada snow depth Snow remote sensing snowmelt trapping effect |
| Abstract |
Recent studies have shown that northern vegetation has been growing in relation to a warming climate over the last four decades, especially across the transition zone between tundra and taiga. Shrub growth affects snow properties and the surface energy budget, which must be better studied to quantify shrub-snow-climate feedbacks. The objective of this research is to improve the characterization of the impact of shrubs on snow evolution, from its accumulation to its melt, using in-situ and satellite measurements. The research is presented for the Umiujaq site, Nunavik, representative of the low Arctic–Subarctic transition zone. Snow depth, measured along numerous transects spanning different land cover types is found to increase by a factor 2.5–3 between tundra and forest, while snow density decreases. This illustrates the trapping effect of vegetation well. Complementary, continuous snow depth measurements using weather stations from two sites (tundra with low shrubs and a small clearing with shrubs within the forest) show different site-dependent behaviors. Spatial analysis from high-resolution Pleiades images combined with Landsat (Normalized Difference Snow Index) and MODIS (Fractional Snow Cover) images suggest a slight delay in melt over open and dense forest areas compared to tundra and dense high shrubs. |
| Programme |
1042 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
0272-3646 |
ISBN |
0272-3646 |
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 |
| Call Number |
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Serial |
6904 |
| Permanent link to this record |
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| Author |
Jouma'a Joffrey, Le Bras Yves, Richard Gaëtan, Vacquié‐Garcia Jade, Picard Baptiste, El Ksabi Nory, Guinet Christophe, Costa Daniel |
| Title |
Adjustment of diving behaviour with prey encounters and body condition in a deep diving predator: the Southern Elephant Seal |
Type |
Journal |
| Year |
2016 |
Publication |
Functional ecology |
Abbreviated Journal |
|
| Volume |
30 |
Issue |
4 |
Pages |
636-648 |
| Keywords |
bio‐logging buoyancy foraging behaviour marine mammal optimal diving theory |
| Abstract |
Summary Optimal diving models have been developed to investigate how air?breathing predators should adjust their diving behaviour to optimize their foraging efficiency. Using time?depth recorders and 3D accelerometers, we addressed this question on six free?ranging Southern Elephant Seal (SES) females equipped on Kerguelen Island. We hypothesize that seals would initially increase their foraging time with distance to the foraging patches before reducing it for physiological reasons, regardless of the prey encountered. We expect that SES spends more time at depths where more Prey Catch Attempts (PCA) occur, that is at the bottom. We also hypothesize that bottom time should be related to both the seal body density and the swimming effort dedicated to catching prey, as we expect seals to be more active when catching prey. Finally, because oxygen is acquired at the surface only, we expect that recovery times increase with the duration of the previous dives. A total of 72·6% of PCA detected by accelerometer occurred at the bottom of the dive. At shallow depths (<300 m), seals spent more time at the bottom in dives where PCA occurred compared to non?PCA dives. At deeper depths, SES had shorter bottom times in PCA dives due to higher swimming effort. When only dives associated with PCA were considered, the time spent at the bottom increased with the number of PCA. In addition, the closer the seal was to neutral buoyancy, the longer was the bottom duration. Body density, that is buoyancy, was found to be a critical factor in controlling variations in the dive duration through the swimming effort to access the prey at the bottom of the dive. Finally, post?dive surface intervals were related to the duration and swimming effort of the previous dive. This study reveals how a marine top predator adjusts the time spent at the bottom depending on its body density, prey encounter rate and prey accessibility. It also highlights that using the duration of the foraging phase as a proxy of foraging success can be seriously misleading in SES. Finally, the need to use an energetic approach with bio?logging technology to study behavioural ecology is emphasized. |
| Programme |
109 |
| Campaign |
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| Address |
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| Corporate Author |
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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 |
0269-8463 |
ISBN |
0269-8463 |
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 |
| Call Number |
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Serial |
6605 |
| Permanent link to this record |
