Physical Geography
  Tectonics and Geology
  Climatic Change
  Climate at Present and in the Past
  Rivers, Lakes, Seas and Wetlands

Biomes & Regions
  Arctic Environments
  Boreal Forests
  Mixed and Deciduous Forests
  Steppe and Forest-steppe
  Arid Environments
  The Mountains of Northern Russia
  The Mountains of Southern Siberia
  The Caucasus
  The Mountains of Central Asia
  Lake Baikal
  The Far East

Environmental Problems
  Radioactive Contamination
  Oil and Gas Development
  Air Pollution
  The Aral Sea Problems
  Deforestation and Degradation of Forests
  Nature Protection and Conservation

Images of Russian Nature
  Geographic Index
  Systematic Index
  Alphabetical Index

Nature Reserves
  Northern Russia
  Central Russia
  Povolzhye (Volga river basin)
  Southern Russia
  Ural Mountains
  Western Siberia
  Eastern Siberia
  Far East

‘отографии природы –оссии
  √еографический каталог
  —истематический каталог
  јлфавитный каталог

Nature Landscapes of the World
  North America
  South America

Field Ecology Education
  Instructive Videos
  Instructive Manuals

Ёкологический ÷ентр Ёкосистема на Facebook Ёкологический ÷ентр Ёкосистема ¬ онтакте

ётуб канал Ёкосистема YouTube EcosystemaRu

—качать приложени€ Ёкосистемы Ёко√ид из магазина Google Play / Play Market
—качать приложени€ Ёкосистемы Ёко√ид из AppStore / iTunes
¬идео-360 по экологии на нашем Youtube канале

Bird Decoys for European Birds: Songs, Calls, Sounds, Bird voices - application for Android download from Google Play / Play Market for free

Share this page with your friends:

( ) : : = = + +

Russian Nature

Home | Physical Geography | Biomes & Regions | Environmental Problems | Images of Russian Nature | Nature Reserves

Our Field Ecology Center published more than 180 methodical materials for nature studies. Some of them are in English:
Mobile educational application: Ecological Field Studies Techniques on Play.Google Mobile field guide Birds of North America: Songs and Calls Decoys on Play.Google WILD FLOWERS OF RUSSIA Field Identification Guide on Play.Google Mobile field guide Birds of Russia on Play.Google Mobile field guide Birds of Russia Songs, Calls and Voices on Play.Google Mobile field guide Birds of Europe Songs, Calls and Voices on Play.Google Mobile field guide Birds of Europe Songs, Calls and Voices on Play.Google
Mobile Educational Apps and Field Identification Guides for Russian, European and American Birds
Applications for Android and iOS are available at GooglePlay and AppStore

Please put an active hyperlink to our site (www.rusnature.info) when you copy the materials from this page

Biomes and Regions of Northern Eurasia

Lake Baikal

<<< Introduction | Biomes & Regions Index | Hydrology of Lake Baikal >>>

Geophysical Features of Lake Baikal and its Catchment

Lake Baikal is situated in one of a series of rift zones, that began to form over 30 million years ago during the Tertiary (Belova et al, 1983). Although the lake has changed shape considerably through geological time, it is thought to be by far the oldest lake in the world. Geological timing of the formation of all basins, and their subsequent deepening is still under debate and is reviewed in Kozhova and Izmesteva (1998). Today, Baikal occupies the world's deepest continental depression, at 1164 m below sea level and is made up of three large basins (graben) of differing ages (Kozhov, 1963; Figure 17.1).

Location of Lake Baikal and major tributaries used to gauge solute budgets

Fig. 17.1 Location of Lake Baikal and major tributaries used to gauge solute budgets

The basins are separated by two underwater highs: the Selenga Shallows in the south, and the Academician Ridge in the north. The rift valley is currently expanding at a rate of c. 2 cm a-1, and is associated with intense seismic activity (SB-RAS, 1996). Only c. 140 years ago, over 200 km2 of land sank below the water surface, forming what is now known as Proval Bay, near the Selenga delta (Galazii, 1991). Lake Baikal itself is surrounded to the east and west by large, steeply sloping mountain ranges (horsts), broken only occasionally by valleys and deltas. These belong to some of the larger rivers, such as the Selenga and Upper Angara, whilst others are preserved from, for example, Pleistocene events.

Although in area Lake Baikal is only the seventh largest fresh-water lake in the world, its great depth means that it contains the largest volume of surface fresh water (23 015 km3) (Kozhov, 1963). A total of 365 rivers flow into Baikal, and there is only one outflow, the Angara in the south basin. The largest inflow is the Selenga that has its source in the Mongolian highlands; this delivers just less than 50 per cent of all water to the lake. General morphological physical characteristics of the lake are summarized in Table 17.1 (Kolokoltseva, 1968).

Morphological characteristics of Lake Baikal

Table 17.1 Morphological characteristics of Lake Baikal

The physical catchment of Lake Baikal occupies an area of c. 540 000 km2, spanning south-eastern Siberia and northern Mongolia (Kozhov, 1963). Over the last two decades, however, an area known as the 'Lake Baikal Region', has expanded to include specified regions outside the immediate catchment area, that are recognized as having a direct influence on catchment properties, for example, through pollution (SB-RAS, 1996) (Figure 17.1). The Region is thus defined by both its physical and political-economic geographies. This regional designation has in turn had an important impact in controlling development around the lake, and has been crucial in the lake obtaining its World Heritage Site status. These zones comprise the following (SB-RAS, 1996):

  • 1. The central zone, which includes the lake and natural parks and reserves around the lake.
  • 2. The buffer zone, which includes the rest of the physical catchment area both within Russia and Mongolia.
  • 3. The zone of atmospheric impact, which occupies an area immediately outside the physical catchment area to the west and north-west of the lake.

The Lake Baikal Region exists at the junction between several biogeographically distinct regions (i.e., Central Asian, eastern Asian, and European-Siberian, consisting of combinations of taiga, tundra, steppe and high mountainous deserts), and consequently has extremely diverse communities of plants and animals (Kozhova and Izmesteva, 1998). Over 2500 vascular plants can be found in the Lake Baikal Region, of which it is estimated about 10 per cent are endemic (SB-RAS, 1996). Major regions of vegetation immediately surrounding the lake are shown in Figure 17.2.

Major vegetation zones within the central zone of the Baikal Lake area

Fig. 17.2 Major vegetation zones within the central zone of the Baikal Lake area. Modified from Atlas Baikala (1993)

Taiga forests are dominated by pine (Pinus sylvestris), larch (Larix sibirica), cedar (Pious sibirica), and fir (Abies sibirica), together with an understorey of various shrubs and grasses. Steppe vegetation is characteristic of the dry Mongolian steppes, often showing a degree of desertification. In the highland zones tundra predominates, although peat is common in depressions and highland plateaux. Near the lake shore, terraces in the north support Larix gmelinii and Rhododendron dahuricum, whilst in other regions extensive areas have been cleared of trees and summer dwelling has proliferated in recent years. Subsistence agriculture is commonly practised by numerous small communities on the shores on parts of the southern and middle basins. The eastern shore of the northern basin is least populated and here dense woodland extends to the lake shore, especially Pinus pumila and Betula папа.

Local terrestrial faunal populations are even more diverse and include some 90 species of mammal, 400 bird species, 20 species of reptiles and amphibians and, what is certainly an underestimate, 5000 species of invertebrates, especially insects and spiders (SB-RAS, 1996). Endemism is particularly common in the Baikal mountains, which also serve to act as a boundary between western and eastern species. Interestingly, lakes other than Baikal within the Lake Baikal Region, contain an impoverished fauna (e.g., fish and invertebrates), perhaps because of past and present severe climate conditions (Kozhova and Izmesteva, 1998). On the other hand, many of these lakes contain relict animal species (Kozhov, 1963) and plants, including algae (Flower et al., 1998).

<<< Introduction | Biomes & Regions Index | Hydrology of Lake Baikal >>>



Recommend this page to your friends:

* *