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About Baikal Lake
Lake Baikal is the world's
oldest and deepest lake. The amazing purity of its
waters, huge territory and deep make it the most famous and exiting lake in the world.
It lies in southern Siberia, almost in the center of Asia. Its watershed extends over the Mongolian border for 636 km. Its area is about 31,500 square kilometers and equal to the area of such countries as Belgium, Switzerland, Netherlands or Denmark. The coastline of Baikal is almost 2000 km long, which is equal to the distance from Arkhangelsk to Rostov. Lake Baikal contains one-fifth of the world's surface water resources, and four-fifth of fresh waters of Russia. Its basin could hold waters of all five American Great Lakes, which are 8 times bigger.
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The Baikal is surrounded by mountain chains which
are covered with taiga lifting turned to bushes and
mountain tundra. The southern hills are generally unforested.
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There is a lot of sun on
Lake Baikal. The number of sunny days at its
costs exceeds the most of resorts on the Black Sea and some on the Mediterranean, for example Nice. In summer the temperature of the water doesn`t outreach the 15 degrees. Below 250 meters the temperature is stable and is about 3.5 degrees for the whole year. In January the Lake is fettered by the thick ice. But because of unusual purity you can look through the ice for more than 12 meters deep.
The lake is indeed old: clay samples taken in 1990 show that Lake Baikal is at least 30 million years old, that makes it the world's oldest known lake. The second old Lake Tanganyika in Africa is at least 500 thousand years younger. In earlier days the territory of the Baikal was a number of shallow lakes inhabited by heat-loving animals and plants. The coasts were covered by subtropical vegetation. The modern shape was formed about 1 million years ago. The process of basin formation is still going on, and sometimes there are earthquakes there.
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More than 300 Siberian rivers fall into Lake
Baikal and only one flows out – the powerful
and quick Angara carrying its waters to the Yenisei. There are 22 islands in the Lake. The biggest one Olhon is 729 square km.
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The lake is revered by the Russian
people as a source of beauty and power.
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Flora and Fauna
The Baikal is also one
of the most interesting biotopes in the world. As
it is quite an isolated lake, the nature there could develop balanced and varied. The animal world of the lake forms a remarkably complementary and harmonies system.
The flora and fauna of the lake are mostly endemic.
It is inhabited by over 58 fish species. The most well-known species are: the omul, Siberian whitefish, the grayling, the taimen, the sturgeon, the Baikal oil fish, and goldilocks. More than 2000 plants grow on the lake coasts. Lake Baikal forms an ideal habitat for typical sea mammal –the nerpa (the Baikal seal). Still not all organisms inhabited Baikal are explored. Scientists continue to discover more and more unknown species.
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Baikal’s Exploration
Preservation of the lake, however, has
recently come to international attention.
The Baikal’s scientific exploration history
is over 300 years, while the harmful impact on its ecosystem numbers merely 50 years.
Industrial and civil buildings have grown and spread, the population has enlarged and new towns and settlements have arisen, new lands have been ploughed up and more chemicals have been used in agriculture.
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Plants and mills
Nowadays there are more than
60 plants and mills along the Baikal’s cost. The
biggest are Baikalsk’s and Selenginsk`s forest transshipment bases and Paper-and-Pulp Mills at Baikalsk and Selenginsk.
The results of the pollution are terrifying. More than 50 per cent of the world's purest water has been ruined. The whole ecological system of the lake has changed greatly. The mills has polluted the surrounding region and threatened the pristine conditions that have existed for centuries.
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Tourists
Every year a lot of tourists from different
countries come to the Lake. People come to see
the reaches of nature and to enjoy the perfect fresh air, but not all of them understand what treasures they possess and don’t spare them. Some people often leave rubbish in the forests and on the coast-line of the Baikal and throw empty bottles in its water, and make fires.
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Measures for Saving the Lake
Of course over
these years measures have been taken aimed at preventing
the threat of pollution. The logging of timber on the rivers has been stopped, many industrial enterprises (including the Selenginsk Paper-and-Pulp Mill) have been converted to close cycle water systems, and environmental education of the local population has been stepped up.
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Volunteers activities
Each year volunteers from different countries come
to collect the garbage.
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However, these measures are insufficient. There is still
the threat of pollution.
If we don’t change our behavior,
very soon we can lose our wonderful nature forever.
