4th Class Science Rocks and Soil / चट्टानें और मिट्टी Soil Erosion

     Soil Erosion

Soil erosion means the removal of the topsoil (the fertile layer) by the action of natural forces, like, wind and water. It is a slow and steady process where the top layer is lost and the land becomes barren and unfit for agriculture. Soil erosion is a natural process but the rate of this process has greatly increased by human activities, which are discussed below.

              Soil Erosion  

           Deforestation

Cutting down of trees is called deforestation. We cut down trees, clear up forests to build our farms, hotels, houses. This provides us both space and the wood for our need. But in the process, as land gets cleared of vegetation, no roots remained to hold the top soil. This leads to an increase in soil erosion. Ploughing of the land leaves the soil loose and this also leads to soil erosion

       Deforestation  

        Overgrazing by Animals

Overgrazing of the land by cattle, goat, sheep, which is reared by human’s beings for their needs, is another cause of soil erosion. Overgrazing exposes the soil by removing the plants shield that protects it. This in turn causes an increase in soil erosion.

Overgrazing of the land by the camels    

     The carrying away of the top soil by natural agents like wind and water is called:

(a) Degradation

(b) Soil pollution

(c) Soil erosion

(d) Leaching                                      

(e) All of the above.

Answer: (c)

      Deforestation is:

(a) Growing of trees

(b) Cutting of trees

(c) Trimming trees

(d) Caring of trees                          

(e) None of the above

Answer: (b)