Soil erosion: what is it and causes, prevention measures, consequences

The problem of soil erosion can be relevant for many land owners. Soil destruction by erosive forces can be catastrophic. Consider what erosion is, its types, what harm it does and what the consequences may be. What climatic zones are most prone to soil erosion, what methods of combating this phenomenon exist.

What is soil erosion

Erosion is the gradual destruction of soil by water, wind, or both. These factors provoke the separation and removal of the surface layer of soil, its deposition elsewhere and the formation of gullies, ravines and even river valleys.

Erosion rate is defined as normal and accelerated. Erosion proceeds at a normal rate, if there is a runoff of water, the processes of destruction proceed more slowly than the formation of soils, a strong change in the relief is not observed. With accelerated erosion, destruction processes outstrip soil formation processes, resulting in soil degradation and a strong change in the former relief.

Erosion occurs for natural reasons, it can also be caused by human activities. Soil destruction occurs everywhere on the planet, but most often in conditions of excessive moisture, when the amount of precipitation exceeds the amount of evaporating water.

Types of erosion

They are divided depending on the factor that causes soil degradation, they can be wind and water.

Wind effect

Wind causes partial or complete destruction of the arable horizon. Wind erosion is divided into everyday, when fertile particles are gradually blown out of the upper horizon and move, while plant roots are exposed; and short-term, when there are dust storms during strong winds and hurricanes.

The wind of any strength has a constant destructive effect on loose soil, especially in arid areas. Usually often in spring, when the wind force exceeds 15 m/s, on loose land without crops.

Wind erosion develops in 4 stages: blowing, soil movement, accumulation and stabilization, which always replace each other. It develops regardless of the relief, its appearance is facilitated by the weakly expressed soil structure, light mechanical composition (mainly sandy), and sparse vegetation.

Rock deflation

The causes of soil destruction are the blowing of soil aggregates and particles from the surface by the wind, transport to different distances and subsequent deposition.

Wind corrosion

Manifested in the impact of wind on rocks, often changes the relief of semi-desert and desert areas, affects agricultural land. Causes dusting, desertification, degradation of soils used in the economy.

Impact of water

Storm and melt water create temporary strong currents that cause erosion. In addition to natural factors, soil is affected by improper economic use of land. The structure of the soil is destroyed by tillage equipment, which leads to the destruction of forests and vegetation that strengthens it with roots, exorbitant grazing of livestock, and dump processing of the soil.

Drip erosion

This is the name of the destruction of the soil by raindrops, which hit the lumps of soil with force and scatter them to the sides. Especially strong destruction is observed on the slopes, where the earth moves downward over long distances. Causes significant damage in humid subtropics and tropics.

Plane erosion

There is also a type of process in which there is a uniform washout of the surface layer from the slopes under the action of small streams, which gradually leads to the leveling of the site.

Linear erosion

This type of erosion process results in the division of the flat surface of the earth and the subsequent formation of gullies, gullies and river valleys, which are formed under the influence of constant water flows.

Irrigation erosion

Caused by improper irrigation, in violation of the regime and irrigation norms, especially in areas with a slope. Usually occurs on arable land, observed in pastures with sandy and sandy soils.

Other types

Among the classification of types of erosion, anthropogenic can be distinguished. Caused by human activity, the cause is: soil pollution, mechanical destruction, destruction of forests and steppe vegetation, plowing large areas, improper processing. As well as the absence of tree strips that protect from the wind, exposing the soil during construction or during mining.

Due to the destruction of the surface layer of the soil, a significant part of the humus is lost, which leads to a loss of fertility, a decrease in plant productivity and huge losses for agricultural enterprises.

Main harm and consequences

Erosion is dangerous in that, as a result of it, soil fertility, agrophysical and chemical properties deteriorate, and bioactivity decreases. The process of destruction leads to a steady decrease in yield, deterioration in product quality. Losses of fertile soils from destructive impact can amount to billions of tons every year. Dust storms can blow out a 10-centimeter layer of humus horizon that takes more than a century to build up.

Negative consequences are also expressed in the clogging of rivers and lakes, which leads to a decrease in the number of fish and other inhabitants of water bodies. Soil from the fields brings with it residues of pesticides and fertilizers, which also dissolve in water, making it toxic. Dust also pollutes the air, which affects the he alth of people and animals. Erosion increases the likelihood of natural disasters - flooding and landslides, which can lead to human casu alties.

Climatic zones most prone to soil erosion

Water erosion is mainly affected by lands located in the zone of forest-steppe and steppe. In Russia, this is the territory of the Central Black Earth region, the North Caucasus and the Volga region. In the Non-Chernozem region, the danger of development of destruction arises on agricultural lands located on the slopes.

The soils of Canada, Australia, China, the USA and India are also subject to erosion processes, as well as many European, Asian and African countries.

Soil erosion control measures

Measures to protect soil from wind and water include agrotechnical, hydrotechnical, reclamation methods of control. Wind erosion in open spaces can be prevented by artificial planting of protective strips of 1 or several rows of trees. They are placed at an angle to the direction in which the prevailing winds blow. The effectiveness of trees in wind protection depends on the height and density of the plants.

Significantly reduce the effect of erosion and protect the soil and helps a dense vegetation cover, consisting of steppe plants with powerful branched roots. Sowing perennial grasses in the fields is also one of the ways to solve the problem. Fields with vegetable crops are temporarily protected from the wind, and cereals are also sown nearby. Other measures are being taken - alternate fields with vegetable crops with fields sown with soil-protective crops. Planting vegetation is today the most effective way that can be done to prevent soil degradation. Plants hold the soil in place, reinforcing it without any additional intervention.

Good effect in the matter of land conservation is obtained from flat-cut processing of fields and slopes, the use of hydraulic structures, growing plants on terraces, soil mulching. In areas where signs of destruction are already clearly expressed, methods of control are used in a complex way.

Soil erosion is a natural phenomenon, every year millions of hectares of land are destroyed by wind and water. Harm is also caused to agricultural lands, not only for natural reasons, but also largely from improper economic use. Land degradation poses a significant threat to ecosystem stability and agricultural land productivity worldwide.

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