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1.  Sub Topic- Soil Erosion and Conservation
                   A.  SoilErosion
                     The washing away of the top layer of soil by the action of wind and water is called soil
                       erosion.

                     Soil formation and soil erosion are simultaneous processes and a balanceexists
                       between thetwo.
                       Activities suchas
                     Deforestation
                     Over-grazing
                     Mining
                     Construction
               Increase the rate of soil erosion and disturb the natural balance.
                     Gully Erosion and Badlands

                     Deep channels called gullies are formed when fast running watercuts through
                       the soft clayey soil making deepravines.
                     This type of land becomes unfit for cultivation and is calledbadland.
                     E.g. Chambal basin in MadhyaPradesh
                     Sheet Erosion: It is caused when water flows as a sheet down a slope and
                       washes- off the top layer of soil. Winds can also blow-off the top layer ofsoil.
                   B.  Degradation Of Soil
                     Soil erosion is the degradation of soil by human activities.
                       Following are the factors responsible for the soil erosion: -
                     Deforestation
                     Overgrazing
                     Construction
                     Overuse of Chemical Fertilizers,Pesticides
                     Natural Calamities (Flood, landslides, etc.)

                   C.  Conservation Of Soil
                       • Soil conservation means protection, preservation and proper utilization of the
                       soil.
                       • Some methods of soil conservation are: -
                     Mulching: Bare ground between plants is covered with a layer of organic matter like
                       straw. It helps to retail soil moisture.
                     Contour Ploughing: Ploughing along contours can decrease the flow of water down the
                       slopes.
                     Terrace Cultivation: Steps can be cut out on the slopes making terraces.
                     Strip Cropping: Strips of grass are grown between the crops. This breaks the force of
                       wind.
                     Shelter Belts: Rows of trees are planted to create shelter. Thus, the speed of wind is
                       reduced.
                     Rock Dam: Rocks are piled to slow the speed of wind.
                     Contour Barriers: Stones, grass, soil are used to make barriers. Trenches are made in
                       front of the barriers to collect water.
                     Afforestation, Crop Rotation, Control over Deforestation and Overgrazing, etc.
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