Still recently in 1961 the ara of the Aral Sea which has arisen in Turanian low-lying 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 slight than on geographical maps Aral is depicted as the enormous puritanical mirror on the Earth. Superfluous confirmation of one of the main(prenominal) features of the twentieth century - even for printing presses, it is difficult to contest with speeds with what people have learned to kill wildlife.
There are umpteen reasons of the Aral accident but as we know main of them this truly sharp reduction of a river drain. Earlier in the sea fell many rivers, but now much wet is expended on the irrigation, the irrigation of the earth of those lying next to the rivers, therefore the adequacy of water does not reach the sea-lake itself.
If to look what the water is expended for, undertaken from the rivers, and so it is possible to see that not entire it is expended rationally. About its half(a) it is spent for so-called washing of fields. After irrigation the water evaporates, and the season remains in the earth, which were contained in this water; therefore it continue by salting and it loses fertility.
The content of salts in the water, in which washes the earth, later on 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 soulfulness 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...
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