Soil erosion - is a common process in which the destruction of the soil and the soil flow and melt streams, storm, rain and irrigation water or winds.The damage from such a huge impact.Soil erosion has brought 2 billion. Ha of land from agricultural use, including arable land (50 million. Hectares).
Soil is a self-healing system, however, to restore the damaged layer thickness of 2.5 cm is required 300-1000 years.
Types of soil erosion - a water and air (deflation).
rill erosion forms, complicating treatment of the soil;It creates gullies, reducing the area of land under crops;destroying roads, flooded farmland.On the upper surface of the short slope is significantly reduced or completely washed away a layer of black earth, which affects the yield.
reasons erosion
on the intensity of the occurrence of erosion processes is very influenced by climate, terrain, anti-erosion resistance of the soil, the vegetation in these areas, the economic activity of people and other factors.
Soil erosion is dependent on climate, because erosion processes are enhanced as a result of sudden changes in temperature, the amount and intensity of rainfall, wind speed and power.Low soil temperatures deep freeze, and the intensity of its thawing and snowmelt affects the rate of water infiltration into the soil, which affects the water flow, erosion and erosion.
water erosion is gully (struychatoy linear) plane and irrigation (irrigation).
If winter with snow slopes demolished by strong winds, the soil is laid bare, and freeze prevents soak melted waters.It causes intense runoff.
Wind also affects the process of water erosion, because it redistributes the snow in relief, blows him from the slopes of ravines, beams and so on. D.
deflation depends on the erosive forces of wind, starting to appear at a speed of about 12 m / s at a heightabout 10 m above the soil surface.
wind speed depends on the vegetation.On the treeless expanses, the steppes, the wind speed sometimes reaches 30 m / s, and in the forest area and forest it is smaller.
Precipitation may significantly reduce wind erosion, but their abundance promotes water.
influence on the intensity of the destruction of the relief, the steepness of the slopes and the length, the width of the watershed.The longer and steeper the slope, the greater the area damaged by erosion and its serious consequences.
condition and characteristics of soil affect the degree of destruction.So qualitatively ostrukturennye, chernozem different porosity, permeability, and therefore the erosion and washing them a lot less.
Soil erosion depends on mechanical composition of soil.Under natural conditions, the air is more susceptible to erosion, light soil - sandy and sandy loam.Clay soils are exposed to deflation only in a loose, dusty condition.Easily destroyed by wind calcareous soils - brown and black earth.Alkaline soils and salt licks - wind resistant.
Thanks vegetation greatly reduced or completely eliminated by the process of soil erosion.Blow raindrops softened by thick vegetation, some of the liquid is held in plant leaves and grass dramatically slows runoff.
Soil erosion is reduced if the land is covered by perennial grasses that protect soil from the impact of rain and wind, increasing the water permeability.
on erosive processes greatly influences the economic activity of people.An increase in the proportion of area planted row crops, increased intensity of soil erosion.
When excessive mechanical tillage takes its spraying, which increases as the wind and water erosion.Soil compaction is a passage on the field of heavy farm machinery, which reduces its water permeability, the water flow increases, blurs and washes.
