In northern latitudes of fresh lakes it is more, than salty therefore the last attract interest. There are questions why the reservoir which eats the rivers contains salt, than its large number from where the whole deposits of this substance at a bottom and coast undertake is caused. Salt lakes – result of lack of drains, evaporations of water, hit of minerals from ground waters and many other reasons.
1. Salt call lakes, salt content in which exceeds 1 per mille. In such lakes, water has sharply salty taste reminding sea water. For drink it is impossible to use it if not to carry out processing. But from them it is possible to extract table salt and minerals, including soda, mirablit.
2. There are two types of lakes: flowing and drainless. They are filled with water approximately equally, eating the rivers, streams, underground waters, an atmospheric precipitation, but water comes out them differently. Flowing lakes have the rivers and streams which of them follow. They bear water from lakes further therefore water is constantly updated. Even if from underground keys or other sources the insignificant amount of salt gets to a reservoir, it leaves together with the following rivers, and only seldom or never its contents is so high that the lake remains salt. In spite of the fact that from them the rivers follow, they are saturated with minerals thanks to the special area in which there are deposits of inorganic compounds.
3. In drainless lakes, water does not leave, and remains in a reservoir. It gradually evaporates, and the salts which appeared in it remain in the lake. In certain cases their contents so is not enough that it is difficult to notice it – if the lake is generally fed with the rivers and streams, then it will save enough salt long centuries and even the millennia. But there are reservoirs which eat underground sources, and water underground can pass through the breeds saturated with salts. Water is enriched with minerals which get to the lake and gradually settle in it. The well-known salt lakes – Baskunchak, Elton, the Caspian and Dead seas are so formed. All of them are in hot and droughty climate with a large number of sunny days, thanks to it water evaporates in large numbers, and salt remains. The closer to the equator, the salt lakes, in comparison with fresh meet more.
4. Many salt lakes are well-known as them much less, than fresh reservoirs. Lake Balkhash is unique the fact that in it there are both fresh, and salty waters: the narrow passage connects these two parts. The largest salt lake on the planet – the Caspian Sea. Elton is the biggest salt lake in Europe.
5. Level of salinity of lakes can change considerably, depending on weather, season, water level. The water level in a reservoir is lower, the it is more in it than salt. By amount of the minerals of the lake dissolved in water divide into saltish, salty and salt.