Problems of Aral Sea

Essay by xtremalkzCollege, UndergraduateA+, February 2005

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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...