Palaeolimnological investigations of coastal continental lakes in the Larsemann Hills
Entry ID: ASAC_2112
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1.The lakes and ponds in the Larsemann Hills and Bølingen Islands (East-Antarctica) are characterised by cyanobacteria-dominated, benthic microbial mat communities. A 56-lake dataset representing the limnological diversity among the more than 150 lakes and ponds in the region was developed to identify the nature and quantify the effects of the abiotic conditions structuring the cyanobacterial and diatom communities.|
2.Limnological diversity in the lakes of the Larsemann Hills and Bølingen Islands is primarily determined by salinity and salinity related variables (concentrations of major ions, conductivity and alkalinity), and variation in lake morphometry (depth, catchment and lake area). Low pigment, phosphate and nitrogen concentrations, and DOC and TOC levels in the water column of most lakes underscore the ecological success of benthic microbial mats in this region.
3.Benthic communities consisted of prostrate, sometimes finely laminated mats, flake mats, epilithic and interstitial microbial mats. Mat physiognomy and chlorophyll/carotenoid ratios were strongly related to lake depth, but not to salinity.
4.Morphological-taxonomic analyses revealed the presence of 27 diatom morphospecies and 34 cyanobacterial morphotypes. Mats of shallow lakes (interstitial and flake mats) and those of deeper lakes (prostrate mats) were characterized by different dominant cyanobacterial morphotypes. No relationship was found between the distribution of these morphotypes and salinity. In contrast, variation in diatom species composition was strongly related to both lake depth and salinity. Shallow ponds are mainly characterised by aerial diatoms (e.g. Diadesmis cf. perpusilla and Hantzschia spp.). In deep lakes, communities are dominated by Psammothidium abundans and Stauroforma inermis. Lakes with conductivities higher than 1.5 mS/cm become susceptible to freezing out of salts and hence pronounced salinity fluctuations. In these lakes Psammothidium abundans and Stauroforma inermis are replaced by Amphora veneta. Stomatocysts were only important in shallow freshwater lakes.
5.Ice cover influences microbial mat structure and composition both directly by physical disturbance in shallow lakes and by influencing light availability in deeper lakes, as well as indirectly by generating salinity increases and promoting the development of seasonal anoxia.
6.The relationship between diatom species composition and salinity and depth is statistically significant. Transfer functions based on these data can therefore be used in paleolimnological reconstruction to infer changes in the precipitation-evaporation balance in continental Antarctic lakes.
These data were also collected under the auspices of the Micromat Project, Biodiversity of Microbial mats in Antarctica (see the url below).
The fields in this dataset are:
Distance from Plateau
Distance from Sea
Total Organic Carbon
Dissolved Organic Carbon
Description: Download point for the data
Link: VIEW PROJECT HOME PAGE
Description: Micromat Project
Link: VIEW PROJECT HOME PAGE
Description: Public information for ASAC project 2112
Link: VIEW RELATED INFORMATION
Description: Citation reference for this metadata record and dataset
|N: -69.15||S: -69.5166||E: 76.4||W: 75.75||
||Min Altitude: 5 M||Max Altitude: 100 M||Min Depth: 0.5 M||Max Depth: 34 M|
|Start Date: 1997-10-29|
|Stop Date: 1998-02-04|
> Larsemann Hills
CONTINENT > ANTARCTICA > Bolingen Islands
CONTINENT > ANTARCTICA > B?lingen Islands
GEOGRAPHIC REGION > POLAR
|TERRESTRIAL HYDROSPHERE >SURFACE WATER >LAKES [Definition]|
|TERRESTRIAL HYDROSPHERE >WATER QUALITY/WATER CHEMISTRY >CONDUCTIVITY [Definition]|
|TERRESTRIAL HYDROSPHERE >WATER QUALITY/WATER CHEMISTRY >PH [Definition]|
|BIOLOGICAL CLASSIFICATION >PROTISTS >DIATOMS [Definition]|
|BIOLOGICAL CLASSIFICATION >BACTERIA/ARCHAEA [Definition]|
|BIOLOGICAL CLASSIFICATION >PLANTS >MICROALGAE >DIATOMS|
|BIOSPHERE >ECOLOGICAL DYNAMICS >SPECIES/POPULATION INTERACTIONS >BIOLUMINESCENCE [Definition]|
ISO Topic Category
|FIELD SURVEYS [Information]|
|FIELD INVESTIGATION [Information]|
|The dates provided in temporal coverage are approximate only, and represent the dates of field data collection rather than laboratory analysis.|
|The dataset is available for download from the url given below.|
This data set conforms to the PICCCBY Attribution License|
Please follow instructions listed in the citation reference provided at the URL below when using these data.
|DISSOLVED ORGANIC CARBON|
|TOTAL ORGANIC CARBON|
Data Set Progress
Australian Antarctic Data Centre, Australia
Data Center URL: http://data.aad.gov.au
Distribution_Size: 430 kb
Distribution_Format: excel, pdf
Role: TECHNICAL CONTACT
Role: DIF AUTHOR
Phone: +44 1223 362616
Fax: +44 1223 362616
Email: daho at pcmail.nerc-bas.ac.uk
HIGH CROSS, MADINGLEY ROAD
British Antarctic Survey
Postal Code: CB3 OET
Country: UNITED KINGDOM
Role: TECHNICAL CONTACT
Phone: +32 4 366 3856
Fax: +32 4 366 2853
Email: awilmotte at ulg.ac.be
University of Liege
Dept of Botany B22
Postal Code: 4000
Sewell, M.A. The meroplankton community of the northern Ross Sea: a preliminary comparison with the McMurdo Sound region. Antarctic science 18(4): 595-602, 2006.
Sewell, M.A., Lavery, S., Baker, C.S. (2006) ‘Whose larvae is that? Molecular identification of planktonic larvae of the Ross Sea’. New Zealand Aquatic Environment and Biodiversity Report No. 3. 57 pp.
Suberg, L. (2008) Diversity, abundance and distribution of coastal meroplankton along the Victoria Land Coast, Antarctica. MSc thesis, University of Auckland, 156 pp.
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