Problems of Aral Sea

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Still recently in 1961 the area of the Aral Sea which has arisen in Turanian lowland 35 thousand years ago, exceeded 66 thousand sq. km. It was considered as one of the biggest lakes in the world. In school textbooks these data are still given in present time, no less than on geographical maps Aral is depicted as the enormous blue mirror on the Earth. Superfluous confirmation of one of the main features of the twentieth century - even for printing presses, it is difficult to compete with speeds with what people have learned to kill wildlife.

There are many reasons of the Aral accident but as we know main of them this very sharp reduction of a river drain. Earlier in the sea fell many rivers, but now much water is expended on the irrigation, the irrigation of the earth of those lying next to the rivers, therefore the sufficiency of water does not reach the sea-lake itself.

If to look what the water is expended for, undertaken from the rivers, then it is possible to see that not entire it is expended rationally. About its half it is spent for so-called washing of fields. After irrigation the water evaporates, and the salt remains in the earth, which were contained in this water; therefore it preserves by salting and it loses fertility. The content of salts in the water, in which washes the earth, after the washing it becomes that threatening to 5-10 gr/l (I want to note that the maximal permissible concentration of salts in the drinking water is 1 gr/l). Soil contains not only salt, but also what the person uses on fields for simplification of the work, i.e. various fertilizers, such as pesticides and defoliates, and, hence, water dissolves all these substances in the ground (in Central Asia such substances use extremely generously - in 5-7 times more than on the average across Russia in water of them contains very much).

After washing fields water dumps into lowlands where it forms huge lakes. From them this dirty water percolates into the wells and other sources of the drinkable water, from where people take water. Because of this in the region of Aral Sea for last decades death rate has increased twice (for example, children's death rate has grown from 4,47 % up to 7,15 %, and in some areas up to 8-9 %), each 12-th child dies. Maternal mortality is 4,3 times higher, than on the average on the countries CIS, at 90 % of women - various chronic diseases, etc., this list can be continued for a long time. For all that there is not even enough water in Aral Sea because it consumption 5-6 times lower than standard.

In comparison with 1961 the sea level has decreased on 13 meters, the water mirror was reduced to 35 percent, and volume of water for 54 percent, that means that more then half was evaporated, shrewd into the air. It has strongly affected a status of the sea, salinity of water has reached 27 grams of salt on liter (in fact the sea once was composed of fresh water). The bottom bared over the area into 23 thousand square kilometers, and the coastal line has receded on 60-8-kilometers. Desertification of Aral Sea region progresses. There is already actually a new desert at that place, where waves rustled not this long before. People have named it Akkum - white sand. It had time to absorb 2 millions the hectares of the previous arable earth.

In Aral Sea were accumulated billions of tons of poisonous salts which have got here together with water after washing fields have collected. From a bottom of the sea constantly rise tens millions tons of a salty dust in which is accumulated a large quantity of the poisonous the substances, which are then taken away by wind up to the very great distances. Especially is dangerous the fact that in the fields in Central Asia for dealing with the disease of the cotton plant (by wilt) is used toxic chemical Dichlorodiphenyltrichloroethane (DDT). This is the connection it is not decomposed in nature and therefore it is very dangerous for the man. Toxic chemicals similar to...
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