Question

Explain any three factors for soil formation.

CBSE Class X Social Science SA ( 3 marks)

Answer 1

Parent material: This refers to the mineral material, or organic material from which the soil is formed. Soils will carry the characteristics of its parent material such as color, texture, structure, mineral composition and so on. For example, if soils are formed from an area with large rocks (parent rocks) of red sandstone, the soils will also be red in color and have the same feel as its parent material. factors of soil formationTime: Soils can take many years to form. Younger soils have some characteristics from their parent material, but as they age, the addition of organic matter, exposure to moisture and other environmental factors may change its features. With time, they settle and are buried deeper below the surface, taking time to transform. Eventually they may change from one soil type to another. factors of soil formationClimate: This is probably the most important factor that can shape the formation of soils. Two important climatic components, temperature and precipitation are key. They determine how quickly weathering will be, and what kind of organic materials may be available on and inside of the soils. Moisture determines the chemical and biological reactions that will occur as the soils are formed. Warmer climate with more rainfall means more vegetative cover and more animal action. It also means more runoff, more percolation and more water erosion. They all help to determine the kind of soils in an area.

Answer 2

(a) The parent rock is the first factor which provides the basic material for the formation of soil.
(b) Climate breaks the parent rock into small pieces.
(c) Vegetation : Plant and animal organisms help in the weathering of the rocks slowly but continuously.
(d) Various forces of nature such as change in temperature, actions of running water, wind and glaciers, activities of decomposers, etc. contribute to the formation of soil.
(e) Chemical and organic changes take place in the soil.