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“Young Scientist” . #7 (66) . May 2014
Technical Sciences
tation and for other needs. In ancient time water level con-
tained 1.5–2.10, was up to natural features of climate, and
amount of water was 100–150 km3, water level area was 400
km3. In dry years amount of water flown into Amudarya and
Syrdarya deltas decreased. So, at present time water level of
the Sea lowered 16.8 m comparing with 1961.
The desiccation of the Aral Sea greatly increased the
number of dust and salt storms in the area. Satellite images
have revealed that there are up to ten major dust storms oc-
curring annually in the region, most of them occurring be-
tween the months of April and July (Glantz 1999). While
before, the pressure from the water surface dampened the
strength of the northerly and north-easterly winds, the loss
of the sea meant that it's protective action from the wind
was significantly reduced. The receding sea left behind large
amount of salt, and ground water evaporation further in-
creased the amount of salt from the exposed sea bed. The
strong north-easterly winds now pick up the sand, salt, and
dust, creating strong dust storms. The salt content in the
dust made up about 30–40 % of the volume in the summer,
and was as high as 90 % in the winter (Hydro meteorolog-
ical Center of Uzbekistan). The storms are often between
150 and 300 km wide. The dust was distributed in areas
far beyond the region — the dust from the Aral Sea region
was found as far as 500km away from the original source
(Micklin 2007). Some of the salt reached the intensively ir-
rigated and cultivated soils, which even ruined the soil far
away from the Aral Sea region. It was estimated that the av-
erage amount of salt removed from the entire dried seabed
was about 43 million metric tons between 1960 and 1984
(Glantz 1999).
The situation in South Island is much worse than other
sides. And area of this island includes Red and Black Sands
and Amu darya. Drying position of Island hasn't been ob-
served in the world experiences yet. That is why there is some
difficulty to mark this case for the world as well. Because of
salinity of ground farm products downed 30 % in Uzbekistan,
33 % in Kazakhstan, 20 % in Kyrgyz republic.
Prior to 1960 the Aral Sea's biodiversity was considered
low. It supported no more than 24 species of fish, over 200
species of free-living macroinvertibrates, and 180 land an-
imal species. With the lowering of water and the rise of sa-
linity and toxicity none of the fish species survived. Less than
30 macroinvertibrate species survived and of the land animals
that were reliant of the Aral Sea a few dozen remain. There
are additional factors that have affected the diminishing na-
tive species of the Aral Sea region. With the receding shores
once water locked breeding grounds of many fish species be-
came vulnerable to land preditors. Also, with the decreasing
volume of animal life in the region more salient species were
introduced in an attempt to preserve the 44,000 tonne of
fish per annum that the commercial fisheries of the region
had procured prior to the 1960's. The newly introduced fish
proved brutal competitors for the already vulnerable native
species. Nowadays, even other animals not only fishes in this
territory are getting few. Nearly there is not an alive creature
in this area. These all impact on population health as well.
This caused some diseases. By learning demographic growth
of population we can get a lot of differences comparing today
with the past in this area. Changes in population are impor-
tant to understand the Aral Sea crisis for various reasons that
we will explore. Between 1950 and 1988, the population of
the Aral Sea basin grew dramatically — from 13.8 to 33.2
million people, comprising increases from 8.1 to 19.9 million
in Uzbekistan, 1.0 to 2.2 million in Kirghizstan, 2.0 to 5.1
million in Tadzhikistan, 1.5 to 3.5 million in Turkmenistan,
and 1.2 to 2.4 million in Kazakhstan (all within the sea-basin
limits). In 1990, the population of the Aral Sea basin num-
bered 34 million. Mean annual rates of population increase
in the late 1980s amounted to 2.85 % in Uzbekistan, 2.60 %
in Kirghizstan, 3.2 % in Tadzhikistan, 2.65 % in Turkmen-
istan, and 1.06 % in southern Kazakhstan. Today, after two
decades of intense demographic growth, the situation has
clearly changed, for we see that the mean of the population
growth rate in the Aral Basin has diminished.
Today the Aral Sea is one of the main problem in in Asia.
Thus a lot of ideas were given for saving the Aral Sea. Some
scientists admit that it is impossible to save the Sea and
whole sea will be dried afterwards. But others admit that it
is possible to save it. And 70 km3 water is needed for saving
the Sea.
To sum up, drying of the Aral Sea is very big problem,
and that's to say it became national trouble for Uzbekistan.
This problem began existing long years ago. And it is still on.
Today it became one of the huge ecological trouble. About 35
million people who live around the sea are under influence of
this problem. Nowadays many scientists have been working
on experiments for solving this problem.
References:
1. «Ecology, biosphere and nature protecting». Ergashev T. A; Tashkent. 2005.
2. «Liberal Bases of ecology».Tashkent. 2004
3. «Respecting nature is all universe problem». Salomova H.;Tashkent. 2004
4. Hydro meteorological Center of Uzbekistan
5. «Sand of lower part of Amudarya».Tursunov L. S; Abdullayev., Tashkent. 1990
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