Advertisements
Advertisements
Question
What is humus? How is it formed? What is its significance in soil formation?
Solution
Humus: Humus is a dark substance formed in soils. It is a dead organic matter formed by the decay of animals and plants. Trees, shrubs, grass, and bacteria help in the formation of humus. In warmer climates, humus is destroyed by countless bacteria. In colder areas, soils are rich in humus and it is collected in the soil. Tropical humid soils are poor in humus because it is consumed by bacteria.
Humus is vital to the fertility of soils. It provides nitrogen, phosphorus, and calcium to the soils. It sustains other forms of life. It helps the weathering of minerals to add to the fertility of soils. It increases the water-holding capacity of soils.
APPEARS IN
RELATED QUESTIONS
In which regions of the world is ‘frost action’ the common form of weathering?
Which is the most important effect of weathering?
What is gradation? Describe the two processes involved in gradation.
What is the chief characteristic of weathering in tropical climates?
Give a technical term for the following:
Peeling off of the outer layer of rock through contraction and expansion.
Say whether the following is ‘True’ or ‘False’.
Shear plane is the surface on which movement of a landslide takes place as a result of its breaking off.
Say whether the following is ‘True’ or ‘False’.
External forces are engaged only in erosion
Distinguish between :
Weathering and Denudation
On what factors does the weathering depend?
Distinguish between the following:
Sheet erosion and gully erosion.
