Question

What is humus? How is it formed? What is its significance in soil formation?

Answer 1

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.