The denudation of the soil cover and subsequent washing down is described as soil erosion. The processes of soil formation and erosion go on simultaneously and generally there is a balance between the two. Sometimes, this balance is disturbed due to human activities like deforestation, overgrazing, construction and mining etc., while natural forces like wind, glacier and water lead to soil erosion. The running water cuts through the clayey soils and makes deep channels as gullies. The land becomes unfit for cultivation and is known as bad land. In the Chambal basin such lands are called ravines. Sometimes water flows as a sheet over large areas down a slope. In such cases the top soil is washed away. This is known as sheet erosion. Wind blows loose soil off flat or sloping land known as wind erosion. Soil erosion is also caused due to defective methods of farming. Ploughing in a wrong way i.e. up and down the slope form channels for the quick flow of water leading to soil erosion. Ploughing along the contour lines can decelerate the flow of water down the slopes. This is called contour ploughing. Steps can be cut out on the slopes making terraces. Terrace cultivation restricts erosion. Western and central Himalayas have well developed terrace farming. Large fields can be divided into strips. Strips of grass are left to grow between the crops. This breaks up the force of the wind. This method is known as strip cropping. Planting lines of trees to create shelter also works in a similar way. Rows of such trees are called shelterbelts. These shelterbelts have contributed significantly to the stabilization of sand dunes and in stabilizing the desert in western India.

Soil Conservation _{Image Courtesy: Wikipedia}

Soil erosion and soil conservation in India

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How soil can be conserved?