Antarctic Lakes as Models for the Study of Microbial Biodiversity, Biogeography and Evolution
The Antarctic continent is almost entirely covered by a
vast icecap that reaches 4 km in thickness. Despite this,
the continent possesses a remarkable array of lake
ecosystems, many of them located in the small ice-free
coastal areas or Antarctic oases, so-called because in
this continental polar desert they are areas supporting
life, albeit sparse. There are some inland ice-free areas
that also have lake ecosystems, notably the largest icefree
expanse of the Dry Valleys in Southern Victoria
Land (Figure 3.1). The lakes of these ice-free regions
range from freshwater to hypersaline (almost seven
times seawater). Some abut onto glaciers, for example,
Chelnock Lake (Vestfold Hills) and maintain thick icecovers
that may be up to 3–5min thickness (Laybourn-
Parry, 2000, unpublished data), while neighbouring
lakes may lose their ice for a few weeks in summer, for
example, Crooked Lake and Lake Druzhby (Laybourn-
Parry et al., 1992; Bayliss et al., 1997). The lakes of the
Dry Valleys lie far south (77S) and are among the most
extreme Antarctic lacustrine ecosystems. They are covered
by debris containing thick ice (up to 4.3 m;
Howard-Williams et al., 1998; Spigel & Priscu, 1998).
Temporary lakes also often form on glacier surfaces.
Although they have not been investigated from a biological
perspective, it is probable that their communities
closely resemble those of cryoconite holes which are a
common feature of glacier surfaces in summer. Such
communities are ephemeral.
Authors: Pearce, David A. ORCID record for David A. Pearce, Laybourn-Parry, Joanna
Editors: Rogers, Alex D., Johnston, Nadine M., Murphy, Eugene J. ORCID record for Eugene J. Murphy, Clarke, Andrew
In: Rogers, Alex D., Johnston, Nadine M., Murphy, Eugene J. ORCID record for Eugene J. Murphy, Clarke, Andrew (eds.). Antarctic Ecosystems: An Extreme Environment in a Changing World, Blackwell Publishing, 63-89.