There are many causes of the Aral Sea disaster, but as we know the main one is a very sharp reduction in the river flow. Earlier in the many rivers empty into the sea, but now a lot of water is used for irrigation, irrigation of land lying near the rivers, so far as the sea, the lake does not reach a sufficient amount of water.
If you look for what is consumed water taken from rivers, we can see that not all of it is spent efficiently. Nearly half of it is spent on the so-called wash fields. After irrigation, the water evaporates and the salt remains in the ground, which were contained in the water, so it zasolyaetsya and lose fertility. The salt content in the water, which washed the ground, after the washing is threatening to 5-10 g / l (I want to note that the maximum allowable concentration of salts in water - 1 g / l). But in the soil contain not only salt but also that the person is using the fields to facilitate their work, that is, various fertilizers, such as pesticides and defolity, and, therefore, all these substances in soil water dissolves (noting that in Central Asia, such substances are used very liberally - in 5-7 times more than the average for Russia, in the water they contain very much).
Water after cleaning the fields reset to the lowlands, where it forms a huge lake. Of them this dirty water seeps into the wells and other sources of drinking water, where people get their water. As a result, in the region of the Aral Sea in recent decades mortality doubled (eg infant mortality rose from 4.47% to 7.15%, and in some areas up to 8-9%), die every 12th child. Maternal mortality is 4.3 times higher than the average in the CIS countries, 90% of women - different chronic diseases, etc., the list goes on. But it is in the basin of the Aral Sea is not even enough water and such, because its consumption is 5-6 times lower than normal.
