question_answer 33)

  Find out the correct sentence about manure (i) Manure contains large quantities of organic matter and small quantities of nutrients. (ii) It increases the water holding capacity of sandy soil. (iii) It helps in draining out of excess of water from clayey soil. (iv) Its excessive use pollutes environment because it is made of animal excretory waste. (a) (i) and (iii)                     (b) (i) and (ii)                      (c) (ii) and (iii)                    (d) (iii) and (iv)

Answer:

  (b) Manures are the natural fertilizers. They are bulky sources of organic matter which supply nutrients in small quantities, and organic matter in large quantities. Manures are prepared by the decomposition of animal excreta and plant waste. Manures include Farm Yard Manure (FYM), compost, green manures, vermicompost etc. Advantages of manures Manures affect the soil in following three ways (i) Manures enrich the soil with nutrients and replenish the general deficiency of nutrients in the soil. (ii) Manures add organic matter (called humus) to the soil which restores the soil texture, for better retention of water and aeration of soil. (iii) The organic matter in manures provides food for the soil organisms, (decomposers such as bacteria, fungi, etc), which help in providing nutrients to plants.