Question

Five factors responsible for the formation of soil are the parent rock, the topography, the climate, the vegetation cover and time.

(i) Parent rock – the original rock from which soil is formed is known as the parent rock for example the black soil is derived from the lava rock.

(ii) Topography- Topographical variations, such as mountains, plateaus and plains affect the thickness of a soil cover.

(iii) Climate – Climatic factors, like temperature and rainfall, affect the soil formation. In the areas of high rainfall and extreme temperature, rocks are easily weathered.

(iv) Vegetation cover – At times, plants grow in the cracks existing in a rock. With time, roots of these plants start penetrating in the cracks and make them wider. As a result, cracks disintegrate into smaller pieces and help in the soil formation.

(v) Time – Time gives maturity to the soil. Although, soil is a renewable resource, yet it takes thousands of years to develop a very thin layer of soil on the earth’s surface.