The permafrost

In the soil are formed the humus, the layer of black color, which is called humus. It contains the basic nutrients, necessary for plants. The greater the humus in the soil, the more fertile it is.As a result the prolonged processes of soil formation occurs the separation of soil thickness into the horizons - the uniform layers, which possess identical color, by structure, by structure and by other signs. For example, in the podsol soils of the mixed scaffolding of temperate zone from top to bottom usually is separated 1 horizon, in which occurs the accumulation of organic matter and the formation of humus; horizon 2 - washing out from which with the sufficiency of sediments occurs the extension of the part of the organic and mineral compounds; the horizon in , where the relatively mobile products of soil formation from the upper levels are accumulated; the horizon - the soil-forming species.By the degree of the manifestation of the separate soil horizons, their power, the chemical composition determine the types of soils - chernozems, podsol soils, solonchaks so forth

Under the conditions of cold climate the water, which is found in the depths and on the surface, freezes through at the depth to 500 m and more. More than 25% surface of the entire land of the Earth are occupied with permafrost species. In our country it is more than 60% such territory, indeed at the zone of its propagation lies almost entire Siberia.This phenomenon was called long-standing, or permafrost. However, climate in the course of time can change to the side of warming up, so that term “long-standing” more is suitable for this phenomenon.