Lacustrine systems of Clearwater Mesa (James Ross Island, north-eastern Antarctic Peninsula): geomorphological setting and limnological characterization
Lentic freshwater habitats are important centres of biodiversity within the infrequent ice-free oases across Antarctica. Given imminent climate changes, it is crucial to catalogue these habitats in order to provide baseline data for future monitoring and biological surveys. The lacustrine systems of Clearwater Mesa, a previously unexplored part of James Ross Island, north-eastern Antarctic Peninsula, are described here. We conducted basic geomorphological and limnological surveys over three Antarctic summers (2009-16) to characterize landscape evolution, infer the origin of lake basins and assess the variability in their water chemistry. Stable shallow lakes, formed in depressions between lava tumuli following the last deglaciation, were found to dominate the volcanic mesa, although several peripheral lakes in ice-proximal settings appear to have formed recently as a result of post-Neoglacial ice recession. We found large heterogeneity in conductivity (similar to 10-7000 mu S cm(-1)), despite the lithologically uniform substrate. This variability was shown to be related to lake type, basin type (open vs closed), meltwater source and proximity to the coast. Inter-annual differences were attributed to changes in sea spray influx and snow accumulation driven by variable weather conditions. Overall, the ion composition of lakes suggested that sea spray was the dominant source of ions, followed by the weathering of bedrock.
1.Masaryk Univ, Fac Sci, Dept Geog, Kotlarska 2, Brno 61137, Czech Republic 2.Charles Univ Prague, Fac Sci, Dept Phys Geog & Geoecol, Albertov 6, Prague 12843 2, Czech Republic 3.Charles Univ Prague, Fac Sci, Dept Ecol, Vinicna 7, Prague 12844 2, Czech Republic 4.Ist Antartico Argentino, 25 Mayo, RA-1143 San Martin, Buenos Aires, Argentina 5.Czech Acad Sci Vvi, Biol Ctr, Inst Hydrobiol, Na Sadkach 7, Ceske Budejovice 37005, Czech Republic 6.Univ Nacl Cordoba, CONICET, Ctr Invest Ciencias Tierra CICTERRA, Av Velez Sarsfield 1611,X5016CGA, Cordoba, Argentina 7.Univ Nacl Cordoba, Fac Ciencias Exactas Fis & Nat, Av Velez Sarsfield 1611,X5016CGA, Cordoba, Argentina 8.Univ South Bohemia, Fac Sci, Ctr Polar Ecol, Na Zlate Stoce 3, Ceske Budejovice 37005, Czech Republic
Recommended Citation:
Roman, Matej,Nedbalova, Linda,Kohler, Tyler J.,et al. Lacustrine systems of Clearwater Mesa (James Ross Island, north-eastern Antarctic Peninsula): geomorphological setting and limnological characterization[J]. ANTARCTIC SCIENCE,2019-01-01,31(4):169-188