The correct option is (c).
Explanation
Manure is a natural fertilizer produced through the decomposition of animal excreta and plant waste. It plays a critical role in agricultural practices by enriching the soil with nutrients and organic matter (humus), which significantly alters the physical structure and fertility of the soil.
Statement 1 is Incorrect
Manure adds a large quantity of organic matter to the soil rather than depleting it. This organic matter is essential for maintaining soil fertility and providing nutrients to plants in small quantities.
Statement 2 is Correct
Sandy soils consist of large particles with large air spaces, resulting in poor water retention. The addition of manure introduces organic matter, which binds the loose sand particles together. This modification significantly increases the water-holding capacity of sandy soils.
Statement 3 is Correct
Clayey soils are composed of fine particles that pack tightly together, often leading to waterlogging and poor aeration. In such soils, the organic matter provided by manure helps to separate the clay particles, preventing them from packing too tightly. This improves the soil structure, thereby facilitating better drainage and aeration.
Key Takeaway
Manure improves soil texture by adding organic matter (humus); it enhances water retention in sandy soils and improves drainage and aeration in clayey soils.