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SAI INTERNATIONAL SCHOOL, BHUBANESWAR.

                                Class VIII: SOCIAL STUDIES – GEOGRAPHY

                 CHAPTER - 2- LAND, SOIL, WATER, NATURAL VEGETATION AND
                                             WILDLIFE RESOURCES

                                               (VIRTUAL CLASSES)


             NOTES FOR CHAPTER-2- Land, Soil, Water, Natural Vegetation and Wildlife Resources


        SUBTOPIC-:Degradation of Soil and Conservation Measures

        Soil degradation is the decline in soil condition caused by its improper use or poor management, usually for
        agricultural, industrial or urban purposes.Soil degradation can be classified into four
        main types :water erosion, wind erosion, chemical deterioration and physical deterioration.

            1.  Deforestation, overgrazing, overuse of chemical fertilizers or pesticides, rain water, landslides
               and floods are the factors which leads to soil degradation.
            2.  Excessive use of fertilizers and high yield crop variety is also a cause of soil degradation and
               leads to loss of fertility of soil.
            3.  Soil conservation refers to the protection, efficient use of soil and preservation of soil .
            4.  Some methods to conserve soil quality are:-
                   o  Mulchingin which the bare ground between plants is covered with a layer of organic
                       matter like straw. This traps moisture in the soil and moderate soil temperature.
                   o  Contour barriers
                            is the method in which stones, grass and soil are used to build barriers along
                              contours with trenches built in front of the barriers to collect water
                            This prevents water to flow down the contours and wash away the soil.
                   o  Rock dams
                            are dams created from rocks that are arranged in a pile to slow down the flow of
                              water and prevent the formation of gullies
                            This reduce the soil erosion
                   o  Terrace farming
                            is where broad flat steps (terraces) are made on the steep slopes to grow crops
                            It reduces the surface run-off and soil erosion.
                   o  Intercropping
                            is a cultivation method in which two or more crops are grown in the same field
                            The crops are grown in proximity in alternate rows.
                            is a widely practiced in China to reduce soil erosion due to rain wash
                            To improve the fertility of soil, mixed farming and crop rotation can  be used.
                   o  Contour ploughing
                            is the method in which the land is ploughed parallel to the contours of a slope
                            This creates a barrier that prevents water from flowing down the slope
                   o  Shelter belts
                            are the rows of trees planted to check the wind movements to protect soil cover
                            is practiced in coastal and dry areas



        IMPORTANT LINKS             https://www.youtube.com/watch?v=-GsQvfYwvbA
                                    https://www.youtube.com/watch?v=W2Se2bPQKpk
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