Answer the following questions.
(a) What is soil made of?
(b) Which are the constituents of plant origin in soil?
(c) What steps can be taken to prevent erosion of soil?
(a) The soil is made up of fine particles of stones, sand, minerals and organic substances in the form of humus.
(b) The constituents of plant or animal origin in the soil are called organic constituents. The constituents of plant origin include algae, blue green algae, decomposed leaves and other parts of plants.
(c) Removal of the upper fertile layer of the soil (top soil) by strong wind or by flowing water is known as soil erosion. The steps that can be taken to prevent soil erosion include:
(i) Tree plantation and growing of crops
(ii) Horizontal arrangement of soil across the line of slope
(iii) Building bunds to stop flowing water that may wash away the soil