Lake Baikal, situated in south-eastern Siberia, has long been recognized as one of the
world's most remarkable fresh-water ecosystems, especially in terms of its age, depth, and
volume, its uninterrupted sedimentary record and the high degree of endemism that exists
within the lake. Lake Baikal is the world's deepest lake (1642 m, Lake Baikal Map, 1992)
and contains the world's largest volume of surface fresh water (some 20 per cent of global
resources; Wetzel, 1983). Another major feature that sets Lake Baikal apart from other
deep lakes is that its entire water column is saturated throughout with oxygen. This is
due to regular renewal of the deep waters every spring and autumn (Weiss et al., 1991;
Shimaraev et al., 1994) and results in the oxidation of even the deepest sediment surfaces
(Leibovich, 1983; Martin et al, 1998). More importantly, this oxygenation supports an
extensive, and almost wholly, endemic deep-water fauna (Fryer, 1991). To date, over 2500
plant and animal species have been documented in Baikal, of which over 75 per cent are
believed to be endemic. The lake is a major biodiversity hotspot, and was declared a World
Heritage Site in 1996.
In this chapter, we will focus on the aspects of Baikal that make it a key site for
scientific study: hydrological and chemical properties; evolution and biodiversity;
paleoclimate history (determined from sedimentary records); and potential threats to the
ecosystem.
