Lake Baikal

General description of Lake Baikal

Lake Baikal is widely known, both in Russia as well as abroad. Especially the attention to this amazing lake has increased in the last 20 years. Through the efforts of specialists, scientists and social movements, Baikal is included in the UNESCO World Heritage List (1996).

Ecosystem of Lake Baikal, including its catchment basin, annually reproduces an average of 60 km3 of water. It is this volume of water (0.26% of the total reserves) that constitutes the renewable resources of Lake Baikal, which now almost completely used by the cascade of the Angara hydropower station. About 350 rivers flow into Lake Baikal, constantly carrying their water to the lake. With small ravines and narrow valleys, which are the channels of temporary streams, formed during precipitation, their number can increase to 1123. The area of the Baikal natural territory (BNT) is 386 thousand square meters. km., which is more than the area of all the other reserves and national parks in Russia combined (317,000 sq. km.), more than the area of Germany, Finland, Italy and Great Britain. The central ecological zone of the BNT (about 90,000 sq. km.) is a site of the UNESCO World Natural Heritage.

Baikal is located almost in the center of Asia, at the latitude of Moscow and London. Its length is 636 km., the maximum width is 79.5 km, minimum - 25 km. The area of the lake's water mirror is 31,500 sq. km., which is roughly equal to the area of such country as Belgium. Having a maximum depth of 1637 m, Lake Baikal is the deepest lake in the world.

Baikal was formed about 30 million years ago and is the oldest lake in the world. It is located in a rift valley, limited by crust fracture, which continues to expand by about 2 cm per year. Baikal is a mountain lake, which located 445 meters above the sea level. The lake bottom is located almost 1200 m below the sea level. The thickness of the lake deposits in a number of places reaches almost 10 km. Information on changes in the climate and geological history of Asia over the past 25-30 million years has been encoded in the sediments of the lake.

Lake Baikal has 23 thousand km3 or 20% of the world's reserves of surface fresh water, which meet the best standards of microbiological, organoleptic and hydrochemical parameters of clean drinking water.

The hollow of lake can accommodate all the water of the Baltic Sea or the water of all North American Great Lakes. River Angara, flowing out of the lake, takes out 2000 m3 of water per second. If the flowing of all the rivers into the lake had stopped, Angara still could have flowed out of Lake Baikal for 360 years. To fill the hollow, the entire annual runoff of the globe's rivers would be needed. The water of Baikal has an unusual purity and transparency. The white Secchi disk used to determine the transparency of water is visible in Baikal to a depth of 40 meters, while the transparency of the Caspian Sea waters does not exceed 25 meters, Lake Sevan - 20 meters. Baikal is also superior to the glorified Alpine lakes in terms of water transparency.

A unique feature of Lake Baikal is the high diversity and endemism of plants and animals. At present, 2,565 species and subspecies of animals and 1,000 species, subspecies and forms of aquatic plants are recorded at Baikal, of which 2/3 are endemic, that is, they are not found anywhere else. To this number, you need to add many hundreds of species of aquatic and benthic microorganisms, as well as little-studied viruses and phages. Species diversity of Lake Baikal has no equal among the ancient and Great Lakes of the World. By the number of species, the fauna of Baikal hydrobionts is more than twice as rich as that of Lake Tanganyika (1,248 species) and almost 13 times more than in Lake Titicaca (South America). Taking into account the fact that more than 20 species of invertebrate animals described annually for Baikal, experts predict the presence of even more than 1500 species of Baikal hydrobionts, which not yet known for science.

Amazing diversity and endemism are common for all types and classes of animals, as well as ecological groups of Baikal hydrobionts.

The top of the trophic pyramid in the ecosystem of the lake is the endemic Baikal seal (seal), whose ancestors, apparently, were Arctic seals, which in ancient times came here along the Lena or the Yenisei. The insular nature of the fauna and flora of Lake Baikal in the Paleoarctic Ocean poses not only important and fascinating biogeographic problems of a global scale, but also practical ones on a differentiated approach to the development of a strategy and tactics for preserving the biodiversity of Southern, Middle and Northern Baikal, as independent biogeographic units of different rank, and transition zones (ecotones).

In addition to the phenomenon of continuous and intensive process of speciation and neoevolution, a number of specific phenomena are observed in Baikal biota: the relative immiscibility of the general Siberian and Baikal fauna, gigantism and dwarfism (ateliosis) of a number of species and groups of hydrobionts, and the complication of the life cycle of animal parasites.

The phenomenon of gigantism most clearly is manifested in deep-sea gammarids, especially the Akantogamaruses, as well as in turbellarians and planarians. It is also observed in diatoms, which dominate in phytoplankton. In some species and groups of organisms, the phenomenon of dwarfism is manifested by the same conditions. Thus, in the phytoplankton a group of algae (diameter of 1.5-3.0 microns) is discovered, which makes up ultranannoplankton, which in certain periods creates a significant share of the primary production (the first food of all consumers) in the Baikal pelagic zone.

Obviously, there is no limit to the knowledge of Baikal's wonders. Recently, near the underwater thermal springs, original biological communities have been discovered, where the organic matter, created not by photosynthesis, but due to chemosynthesis from methane, is the first food. Similar communities were previously known for oceanic depths. The old thesis: Baikal is the same as the ocean, has acquired a new confirmation.

Preservation of Lake Baikal for future generations as a world source of fresh water and as a natural site with unique landscapes, fauna and flora is the most important condition for the sustainable development of the Baikal region.

Информационный портал БАЙКАЛ-LAKE http://baikal-center.ru

Lake Baikal in figures: