Lake Baikal, the world`s oldest and deepest freshwater lake, curves

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Lake Baikal
Is One of the Wonders of Russia
Done by Yan Semenichev
Teacher: L. Sharuda
Lake Baikal
Baikal: The oldest and deepest freshwater lake in the world
Lake Baikal, the world's oldest and deepest freshwater lake, curves for nearly
400 miles through south-eastern Siberia, north of the Mongolian border. It lies
in a cleft where Asia is literally splitting apart, the beginnings of a future ocean.
Geologists say Baikal today shows what the seaboards of North America, Africa
and Europe looked like as they began to separate millions of years ago.
More than 5,000 feet deep (1637m) at its most profound, with another fourmile-thick layer of sediment further down, the lake's cold, oxygen-rich waters
teem with bizarre life-forms.
One of those is the seals' favourite food, the golomyanka, a pink, partly
transparent fish which gives birth to live young. Geologists estimate that Lake
Baikal formed somewhere 20-25 million years ago, during the Mesozoic.
Surrounded by mile-high snowcapped mountains, Lake Baikal still offers vistas
of unmatched beauty. The mountains are still a haven for wild animals, and the
small villages are still outposts of tranquillity and self-reliance in the remote
Siberian taiga, as the forest is called.
Interesting Facts about Lake Baikal
Lake Baikal, in eastern Siberia, is no ordinary lake. Here are some interesting
facts about it:
 Lake Baikal is the deepest lake in the world with a maximum depth of
1,632m
 It is also the world's largest volume of fresh water 23,000 cubic km.
 This means that one-fifth of all the fresh water in the world is located here
at Lake Baikal.
 Lake Baikal is 640km long and judging by its dimensions only it would be
more of a sea than a lake.
 Baikal is also the world's most ancient freshwater lake, it originated 20-25
million years ago.
 It is home to many unique species of animals and plants including the
freshwater seal.
 Lake Baikal is one of the clearest and purest bodies of water. In a good day
you could see 40 meters into the lake.
 Dimensions of Lake Baikal: It is 636 km long, 79 km wide.
 There are 27 islands in Lake Baikal, most of them being uninhabited.
 Baikal Lake’s coastline measures 2100 kilometers (around 1300 miles).
 More than 300 streams and rivers flow into Lake Baikal, but there is just
one outlet, the Angara.
 The water in the lake creates a mild microclimate around its shores.
 More than half the species found in Lake Baikal are unique to this place.
Flora and Fauna
Lake Baikal, formed 25 million years ago, provides a haven for 1,200 animal
species, 600 types of plants, and the world's only freshwater seals.
Of these plants and animals, 75 percent are found only in the Lake Baikal region,
making its preservation crucial.
Some of Baikal's fish can survive more than one mile beneath the surface,
despite the incredible water pressure at that depth.
They are so well-adapted to these pressures that they will literally explode if
brought to the surface, where the pressure is dramatically different.
Out of all the animals living in the Lake Baikal, the most interesting are the fresh
water seals.
Scientists still have not determined how the seals got to Lake Baikal, although it
is supposed that they travelled here in prehistoric times from the Arctic through
a river.
The nerpas – how they are often called – differ in many aspects from the Arctic
seals as they have adapted to the Baikal climate. For example they have more
blood, which makes it possible to them to swim for more than 70 minutes. They
can also travel at great depths, sometimes reaching depths of 300 meters under
the surface.
One of the most bizarre fish that lives in Lake Baikal is the golomyanka (oil-fish).
The golomyanka has no scale and a translucent body. It can swim at depths of
more than 1000 metres.
The omul is the most popular fish in Lake Baikal and you will find it in most
tourist towns as it is the main food supply of the locals.
Rivers and Islands
Half the water flowing into the lake comes down the Selenga River in the
southeast.
The rest comes from more than 330 other rivers and streams, many of them
flowing from the surrounding mountains. Lake Baikal’s only outlet is the Angara
River, which flows westward from the lake’s southwestern end.
Lake Baikal has about 45 islands and islets, of which the two biggest are Olkhon,
about 270 square miles (700 square kilometers) in area, and Great Ushkany,
which covers only about 3.6 square miles (9.4 square kilometers).
Olkhon is a region of forests and grasslands that supports deer, brown bears,
and a wide range of birds.
Great Ushkany is rocky, the site of the largest rookery of Baikal seals. Many of
the other islands are little more than rocks, used as roosts by water birds.
Climate
Because large bodies of water retain heat longer than land, the climate around
Lake Baikal is much milder than in the rest of southern Siberia.
Even in the depths of winter the average air temperature is -6°F (-21°C),
compared with minimum temperatures of -68°F (-90°C) elsewhere in Siberia.
In August, the average air temperature is 52°F (11°C).
The lake freezes over from January until May or June, but its surface
temperature in August is between 50 and 54°F (10–12°C).
Lake Baikal’s water is very clear because it contains very few mineral salts.
From the surface it is possible to see objects 130 feet (40 meters) below.
This clarity is maintained by large numbers of planktonic animals eating floating
debris. In spite of its great depth the water in the lake is well mixed, and oxygen
is plentiful even in the bottom waters.
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