21- Soil erosion and depletion are the major threats to ……………
(A) Soil
(B) Rainfall
(C) Climate
(D) None of the above
22- Which of the following factors lead to soil degradation?
(A) Deforestation
(B) Over grazing
(C) Rain wash and floods
(D) All of the above
23- Mulching, contour barriers, rock dams, terrace farming, intercropping, contour ploughing and shelter belts are methods of ……………………..
(A) Soil degradation
(B) Soil erosion
(C) Soil Conservation
(D) None of the above
24- The bare ground between plants is covered with a layer of organic matter like straw. This type of soil conservation is called ………………
(A) Terrace farming
(B) Rock dam
(C) Contour barrier
(D) Mulching
25- In which type of soil conservation method we use a layer of organic matter between plants?
(A) Intercropping
(B) Shelter belts
(C) Rock dam
(D) Mulching
26-In which type of soil conservation method stones, grass, soil are used to build barriers along contours?
(A) Contour barriers
(B) Shelter dams
(C) Terrace farming
(D) Contour ploughing
27- ………………are made in contour barrier method to collect water in front of the barrier.
(A) Shelter belts
(B) Trenches
(C) Terrace farming
(D) Intercropping
28- ……………….are piled up to slow down the flow of water and this prevents gullies and further soil loss.
(A) Intercropping
(B) Mulching
(C) Rock dam
(D) All of the above
29- ……………….are made on the steep slopes so that flat surface are available to grow crops.
(A) Mulching
(B) Plantation
(C) Intercropping
(D) Terrace farming
30- In ………………soil conservation method, different crops are grown in alternate rows and are sown at different times to protect the soil from rain wash.
(A) Intercropping
(B) Mulching
(C) Both A and B
(D) None of the above
ANSWERS:
21-(A), 22-(D), 23-(C), 24-(D), 25-(D), 26-(A), 27-(B), 28-(C), 29-(D), 30-(A)