Lake Baikal

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Image:LakeBaikal.png Image:Yenisei basin 7.png

Lake Baikal is the largest (by volume), deepest and oldest freshwater lake in the world. A World Heritage Site, it lies in Southern Siberia in Russia, between Irkutsk Oblast to the northwest and Buryatia to the southeast, near the city of Irkutsk. The name derives from Tatar "Bai-Kul" - "rich lake". It is also known as the Blue Eye of Siberia. In Russian, it is called О́зеро Байка́л (Ozero Baykal), and in the Buryat and Mongol languages it is called Dalai-Nor, or "Sacred Sea".

1 Geography and Hydrography
2 Wildlife
3 See also
4 References
5 External links

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Geography and Hydrography

Very little was known about Lake Baikal until work began on the Trans-Siberian railway. The scenic loop encircling Lake Baikal required 200 bridges and 33 tunnels. At the same time (1896–1902) a large hydrogeographical expedition headed by F.K. Drizhenko produced the first detailed atlas of the contours of Baikal's depths.

Baikal has as much water as all of North America's Great Lakes combined — 23,000 km³, about 20% of the total fresh water on the Earth. However, in surface area, it is exceeded by the much shallower Great Lakes Superior, Huron and Michigan, as well as by the relatively shallow Lake Victoria in East Africa and the second largest in volume, Central Africa's Lake Tanganyika. Known as the "Galápagos of Russia", its age and isolation have produced one of the world's richest and most unusual freshwater faunas, which is of exceptional value to evolutionary science.

At 636 kilometres long and 80 km wide, Baikal has the largest surface area of any freshwater lake in Asia (31,494 km²) and is the deepest lake in the world (1637 metres, previously measured at 1620 metres). The bottom of the lake is 1285 metres below sea level, but below this lies some 7 km (4 miles) of sediment, placing the rift floor some 8–9 km (more than 5 miles) down: the deepest continental rift on Earth. In geological terms, the rift is young and active — it widens about 2 centimeters per year. The fault zone is also seismically active: there are hot springs in the area and notable earthquakes every few years.

Its age is estimated at 25–30 million years, making it one of the most ancient lakes in geological history. It is unique among large, high-latitude lakes in that its sediments have not been scoured by overriding continental ice sheets. US and Russian studies of sediment cores in the 1990s provide a detailed record of climatic variation over the past 250,000 years. Longer and deeper sediment cores are expected in the near future. If all the sediment were scoured from the lake, it would be 9 km deep.

The lake is completely surrounded by mountains, technically protected as a national park and contains 22 small islands, the largest, Olkhon, being 72km long. The lake is fed by some 300 inflowing rivers, the six main ones being Selenga, the source of some of Baikal's pollution, Chikoy, Khiloh, Uda, Barguzin and Upper Angara, and is drained through a single outlet, the Angara River.

Despite its great depth, the lake's waters are well-mixed and well-oxygenated throughout the water column. (Compare to the notable stratification of bodies such as Lake Tanganyika and the Black Sea.)

Baikal is renowned for the unique clarity of its waters. Muted protest about the establishment of a wood pulp and cellulose plant at the south end of the lake, at Baikalsk, first planned in 1957, originated ecological awareness among educated Russians, though not among the Soviet bureaucracy. The plant still pours industrial effluent into Baikal's waters. The overall impacts of watershed pollution on Baikal and similar watersheds is studied annually by the Tahoe Baikal Institute, an exchange program between the U.S. and Russian and Mongolian scientists and university graduate students started in 1989.

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Wildlife

Image:Omul Fish.jpg

The extent of biodiversity present in Lake Baikal is equalled by few other lakes. Lake Baikal hosts 1085 species of plants and 1550 species and varieties of animals. Over 60% of animals are endemic; e.g., of 52 species of fish 27 are endemic. The Baikal Seal (Phoca sibirica), the only mammal living in the lake, is found throughout the whole area of the lake.

Of note is an endemic subspecies of the omul fish (Coregonus autumnalis migratorius). It is fished, smoked, and sold on all markets around the lake. For many travellers on the Trans-Siberian railway, purchasing smoked omul is one of the highlights on the long journey.

Bears and deer are observable and hunted along Baikal coasts.

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