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Author | Bart Van de Vijver, Luc Ector | ||||
Title | Microcostatus elisabethianus, a new limnoterrestrial diatom species (Bacillariophyta) from the sub-Antarctic region | Type | Journal | ||
Year | 2019 | Publication | Plant Ecology and Evolution | Abbreviated Journal | |
Volume | 152 | Issue | 3 | Pages | 539-545 |
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Abstract | Background and aims – During a survey of the soil diatom flora of the sub-Antarctic islands in the southern Indian Ocean, an unknown small-celled naviculoid taxon was discovered living in small cracks in cliffs bordering the ocean. The taxon showed a set of morphological features only found in the genus Microcostatus. However, the unknown taxon could not be identified using the currently available literature. Methods – Using both light microscopical and scanning electron microscopical techniques, the morphology of the unknown Microcostatus taxon was documented. The new taxon is described, illustrated and compared with all other similar Microcostatus taxa worldwide. Key results – Microcostatus elisabethianus possesses a unique combination of morphological features that excludes conspecificity with all other members of the genus. It is characterized by a lanceolate valve outline with protracted, elongate apices, a very large, porous conopeum reaching the valve margins and uniseriate striae composed of only one macroareola and mantle areolae restricted to the valve apices. The morphological features of the genus Microcostatus are evaluated and discussed. Notes on the occurrence and ecology of the new taxon are added. | ||||
Programme | 136 | ||||
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ISSN ![]() |
2032-3921 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 7713 | |||
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Author | Barbora Chattová, Marc Lebouvier, Vít Syrovátka, Bart Van de Vijver | ||||
Title | Moss-inhabiting diatom communities from Ile Amsterdam (TAAF, southern Indian Ocean) | Type | Journal | ||
Year | 2021 | Publication | Plant Ecology and Evolution | Abbreviated Journal | |
Volume | 154 | Issue | 1 | Pages | 63-79 |
Keywords | Bacillariophyta diatoms ecology Ile Amsterdam mosses southern Indian Ocean sub-Antarctic region | ||||
Abstract | Background and aims – Despite the ongoing taxonomical revision of the entire (sub)-Antarctic diatom flora, our knowledge on the ecology and community associations of moss-inhabiting diatoms is still rather limited. In the present study, our research aim was to survey the diversity together with the environmental factors structuring the epiphytic moss diatom communities on Ile Amsterdam (TAAF), a small volcanic island in the southern Indian Ocean.Material and methods – A morphology-based dataset and (physico)chemical measurements were used for the ecological and biogeographical analysis of moss-inhabiting diatom flora from Ile Amsterdam. In total, 148 moss samples were examined using light microscopy.Key results – The analysis revealed the presence of 125 diatom taxa belonging to 38 genera. The uniqueness of the Ile Amsterdam diatom flora is mainly reflected by the species composition of the dominant genera Pinnularia, Nitzschia, Humidophila, and Luticola, with a large number of unknown and often new species. This highly specific diatom flora, together with differences in the habitats sampled and the isolated position of the island, resulted in very low similarity values between Ile Amsterdam and the other islands of the Southern Ocean. From a biogeographical point of view, 40% of the taxa have a typical cosmopolitan distribution, whereas 22% of all observed species can be considered endemic to Ile Amsterdam, with another 17% species showing a restricted sub-Antarctic distribution. The NMDS analysis, based on a cluster dendrogram, divides the samples into six main groups. For each group, indicator species were determined. Both environmental data and diatom distributions indicate that apart from elevation, specific conductance, pH, and moisture are the major factors determining the structure of moss-inhabiting diatom communities on Ile Amsterdam.Conclusion – The isolated geographic position and unique climatological and geological features of the island shaped the presence of a unique diatom flora, characterised by many endemic species. The results of the study are of prime importance for further (palaeo-)ecological and biogeographical research. | ||||
Programme | 136 | ||||
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2032-3921 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 7974 | |||
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Author | Van de Vijver Bart, de Haan Myriam, Lange-Bertalot Horst, | ||||
Title | Revision of the genus Eunotia (Bacillariophyta) in the Antarctic Region | Type | Journal Article | ||
Year | 2014 | Publication | Plant Ecology and Evolution | Abbreviated Journal | |
Volume | 147 | Issue | 2 | Pages | 256-284 |
Keywords | ANTARCTIC REGION, BACILLARIOPHYTA, BIOGEOGRAPHY, EUNOTIA, MORPHOLOGY, NEW SPECIES, TAXONOMY, | ||||
Abstract | Background and aims – The past few years, the limnoterrestrial and aquatic diatom flora of the entire Antarctic Region (sub-Antarctic islands, Maritime Antarctic Region, Antarctic Continent) is currently under revision. One of the genera that still needed a revision is the genus Eunotia, quite common in wet to semi-wet moss vegetations in the sub-Antarctic and Maritime Antarctic Region.
Methods – Using both Light Microscopical and Scanning Electron Microscopical techniques, the morphology of all Eunotia taxa, present in the samples from the Antarctic Region, has been analysed. Each taxon is properly described, illustrated and compared with all other possible similar Eunotia taxa, known worldwide. Key results – A total of nineteen Eunotia taxa has been found of which one remains unidentified and is discussed as Eunotia sp. 1. Six taxa could be identified using the currently available literature: Eunotia meisterioides Lange-Bert., E. muscicola Krasske var. muscicola, E. paludosa Grunow var. paludosa, E. pyramidatoides, E. seminulum Nörpel-Schempp & Lange-Bert. and E. tecta Krasske. Ten new Eunotia species and two new subspecies are described: Eunotia amayae sp. nov., E. amayae subsp. heardensis subsp. nov., E. australomaior sp. nov., E. clotii sp. nov., E. frigida sp. nov., E. mcbridei sp. nov., E. mourotii sp. nov., E. muscicola subsp. polyglyphis subsp. nov., E. parallelogramma sp. nov., E. pseudopaludosa sp. nov., E. ralitsae sp. nov. and E. subantarctica sp. nov. Conclusions – The obtained results confirm the presence of a typical and highly specific limnoterrestrial diatom flora in the Antarctic Region and contradict the generally accepted idea about the worldwide distribution of diatoms. |
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Programme | 136 | ||||
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ISSN ![]() |
2032-3913 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 5166 | |||
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Author | Van de Vijver Bart, | ||||
Title | Revision of the genus Halamphora (Bacillariophyta) in the Antarctic Region | Type | Journal Article | ||
Year | 2014 | Publication | Plant Ecology and Evolution | Abbreviated Journal | |
Volume | 147 | Issue | 3 | Pages | 374-391 |
Keywords | |||||
Abstract | Background and aims – The limnoterrestrial and aquatic diatom flora of the entire Antarctic Region (sub-Antarctic islands, Maritime Antarctic Region, Antarctic Continent) is currently under revision. One of the genera that still needed a thorough analysis is the genus Halamphora, recently split off from Amphora. Halamphora species are a typical constituent of the lake diatom flora in the Antarctic region.
Methods – Using both Light Microscopical (LM) and Scanning Electron Microscopical (SEM) techniques, the morphology of a large number of Halamphora taxa, present in the samples from the Antarctic Region, has been analysed. Each taxon is properly described, illustrated and compared with other morphologically similar Halamphora taxa, known worldwide. Key results – A total of seven Halamphora taxa has been found. Two taxa could be identified using the currently available literature: Halamphora veneta (Kütz.) Levkov and H. oligotraphenta (Lange-Bert.) Levkov. Five new Halamphora species are described: Halamphora ausloosiana Van de Vijver & Kopalová sp. nov., H. compereana Van de Vijver & Levkov sp. nov., H. dagmarobbelsiana Van de Vijver & Levkov sp. nov., H. lateantarctica Van de Vijver, Kopalová, Zidarova & Levkov sp. nov. and H. vyvermaniana Van de Vijver, Kopalová, Zidarova & Levkov sp. nov. Conclusions – The obtained results confirm the presence of a typical and highly specific limnoterrestrial diatom flora in the Antarctic Region and contradict the generally accepted idea about the worldwide distribution of diatoms. |
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Programme | 136 | ||||
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Publisher | Botanic Garden Meise and Royal Botanical Society of Belgium | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN ![]() |
2032-3913 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 5755 | |||
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Author | Van de Vijver B., Jütttner I. | ||||
Title | Eunotia manguinii nom. et stat. nov. (Bacillariophyceae), a new name for the sub-Antarctic Eunotia populations formerly identified as E. muscicola Krasske | Type | Journal | ||
Year | 2018 | Publication | Notulae algarum | Abbreviated Journal | |
Volume | 59 | Issue | Pages | ||
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Programme | 136 | ||||
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2009-8987 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 4443 | |||
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Author | E. Le Meur, M. Sacchettini, S. Garambois, E. Berthier, A. S. Drouet, G. Durand, D. Young, J. S. Greenbaum, D. D. Blankenship, J. W. Holt, E. Rignot, J. Mouginot, Y. Gim, D. Kirchner, B. de Fleurian, O. Gagliardini and F. Gillet-Chaulet | ||||
Title | Two independent methods for mapping the grounding line of an outlet glacier – example from the Astrolabe Glacier, Terre Adélie, Antarctica | Type | Journal Article | ||
Year | 2013 | Publication | The Cryosphere Discuss. | Abbreviated Journal | The Cryosphere Discuss. |
Volume | 7 | Issue | 4 | Pages | 3969-4014 |
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Abstract | Abstract
The grounding line is a key element acting on the dynamics of coastal outlet glaciers. Knowing its position accurately is fundamental for both modelling the glacier dynamics and establishing a benchmark to which one can later refer in case of change. Here we � �map the grounding line of the Astrolabe Glacier in East Antarctica (66 41 S; 140 05 E), using hydrostatic and tidal methods. The first method is based on new surface and ice thickness data from which the line of buoyant flotation is found. We compare this hydrostatic map with kinematic GPS measurements of the tidal response of the ice surface. By detecting the transitions where the ice starts to move vertically in response to the tidal forcing we find control points for the grounding line position along GPS profiles. With the help of a 2-dimensional elastic plate model, rigid elastic deviations are computed and applied to these control points. Once the extent of the grounding zone, the kinematic approach is consistent with the hydrostatic map. These two approaches lead us to propose a grounding line for the Astrolabe Glacier that significantly deviates from those obtained so far from satellite imagery. |
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Programme | 1053 | ||||
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1994-0440 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 4397 | |||
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Author | Picard G, Royer A, Arnaud L, Fily M, | ||||
Title | Influence of meter-scale wind-formed features on the variability of the microwave brightness temperature around Dome C in Antarctica | Type | Journal Article | ||
Year | 2013 | Publication | The Cryosphere Discuss. | Abbreviated Journal | The Cryosphere Discuss. |
Volume | 7 | Issue | 4 | Pages | 3675-3716 |
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Abstract | Space-borne passive microwave radiometers are widely used to retrieve information in snowy regions by exploiting the high sensitivity of microwave emission to snow properties. For the Antarctic Plateau, many studies presenting retrieval algorithms or numerical simulations have assumed, explicitly or not, that the subpixel-scale heterogeneity is negligible and that the retrieved properties were representative of whole pixels. In this paper, we investigate the spatial variations of brightness temperature over a range of a few kilometers in the Dome C area. Using ground-based radiometers towed by a vehicle allowing measurements with meter resolution, we collected brightness temperature transects at 11, 19 and 37 GHz at horizontal and vertical polarizations. The most remarkable observation was a series of regular undulations of the signal with a significant amplitude of up to 10 K at 37 GHz and a quasi-period of 30–50 m. In contrast, the variability at longer length scales seemed to be weak in the investigated area and the mean brightness temperature was close to AMSR-E and WindSat satellite observations for all the frequencies and polarisations. To establish a link between the snow characteristics and undulation-scale variations of microwave emission, we collected detailed snow grain size and density profiles to run the DMRT-ML microwave emission model at two points where opposite extrema of brightness temperature were observed. The numerical simulations revealed that the difference in density of the upper first meter of the snowpack explained most of the brightness temperature variations. In addition, we found in the field that these variations of density were linked to the hardness of the snowpack. Areas of hard snow – probably formed by the wind – were clearly visible and covered as much as 39% of the investigated area. Their brightness temperature was higher than in normal areas. This result implied that the microwave emission measured by satellites over Dome C is more complex than expected and very likely depends on the areal proportion of the two different types of areas having distinct snow properties. | ||||
Programme | 902 | ||||
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1994-0440 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 4457 | |||
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Author | Favier V, Agosta C, Parouty S, Durand G, Delaygue G, Gallée H, Drouet A-S, Trouvilliez A, Krinner G, | ||||
Title | An updated and quality controlled surface mass balance dataset for Antarctica | Type | Journal Article | ||
Year | 2012 | Publication | The Cryosphere | Abbreviated Journal | |
Volume | 6 | Issue | 5 | Pages | 3667-3702 |
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Abstract | We present an updated and quality controlled surface mass balance (SMB) database for the Antarctic ice sheet. We retrieved a total of 5284 SMB data documented with important meta-data, to which a filter was applied to discard data with limited spatial and temporal representativeness, too small measurement accuracy, or lack of quality control. A total of 3438 reliable data was obtained, which is about four times more than by applying the same data filtering process to previously available databases. New important data with high spatial resolution are now available over long traverses, and at low elevation in some areas. However, the quality control led to a considerable reduction in the spatial density of data in several regions, particularly over West Antarctica. Over interior plateaus, where the SMB is low, the spatial density of measurements remained high. This quality controlled dataset was compared to results from ERA-Interim reanalysis to assess model representativeness over Antarctica, and also to identify large areas where data gaps impede model validation. Except for very few areas (e.g. Adelie Land), the elevation range between 200 m and 1000 m a.s.l. is not correctly sampled in the field, and measurements do not allow a thorough validation of models in regions with complex topography, where the highest scattering of SMB values is reported. Clearly, increasing the spatial density of field measurements at low elevations, in the Antarctic Peninsula and in West Antarctica remains a scientific priority. | ||||
Programme | 411 | ||||
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ISSN ![]() |
1994-0440 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 4582 | |||
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Author | Verfaillie D, Fily M, Le Meur E, Magand O, Jourdain B, Arnaud L, Favier V, | ||||
Title | Snow accumulation variability in Adelie Land (East Antarctica) derived from radar and firn core data. A 600 km transect from Dome C | Type | Journal Article | ||
Year | 2012 | Publication | The Cryosphere Discuss. | Abbreviated Journal | The Cryosphere Discuss. |
Volume | 6 | Issue | 4 | Pages | 2855-2889 |
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Abstract | The mass balance of ice sheets is an intensively studied topic in the context of global change and sealevel rise. However – particularly in Antarctica – obtaining mass balance estimates remains difï¬cult due to various logistical problems. In the framework of the TASTE-IDEA (Trans-Antarctic Scientiï¬c Traverses Expeditions – Ice Divide of East Antarctica) program, an International Polar Year project, continuous ground penetrating radar (GPR) measurements were carried out during a traverse in Adelie Land (East Antarctica) during the 2008–2009 austral summer between the Italian–French Dome C (DC) polar plateau site and French Dumont D’Urville (DdU) coastal station. The aim of this study was to process and interpret GPR data in terms of snow accumulation, to analyse its spatial and temporal variability and compare it with historical data and modelling. The focus was on the last 300 yr, from the preindustrial period to recent times. Beta-radioactivity counting and gamma spectrometry were applied to cores at the LGGE laboratory, providing a depth–age calibration for radar measurements. Over the 600 km of usable GPR data, depth and snow accumulation were determined with the help of three distinct layers visible on the radargrams (≈ 1730, 1799 and
1941 AD). Preliminary results reveal a gradual increase in accumulation towards the coast (from ≈ 3 cm w.e. a-1 at Dome C to ≈ 17 cm w.e. a-1 at the end of the transect) and previously undocumented undulating structures between 300 and 600 km from DC. Results agree fairly well with data from previous studies and modelling. Drawing ï¬nal conclusions on temporal variations is difï¬cult because of the margin of error introduced by density estimation. This study should have various applications, including model validation. |
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Programme | 411 | ||||
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1994-0440 | ISBN | Medium | ||
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Notes | Approved | yes | |||
Call Number | Serial | 4589 | |||
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Author | Cavitte M G P, Blankenship D D, Young D A, Siegert M J, Le Meur E, | ||||
Title | Radar stratigraphy connecting Lake Vostok and Dome C, East Antarctica, constrains the EPICA/DMC ice core time scale | Type | Journal Article | ||
Year | 2013 | Publication | The Cryosphere Discuss. | Abbreviated Journal | |
Volume | 7 | Issue | 1 | Pages | 321-342 |
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Programme | 1053 | ||||
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Publisher | Copernicus Publications | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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1994-0440 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | yes | |||
Call Number | Serial | 4788 | |||
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