Question

How living organisms help in the formation of soil? Give examples.

Answer 1

Over thousands and millions of years, the rocks at or near the surface of

the Earth are broken down by various physical, chemical, and biological

processes. The end product of this breaking down is the fine particles of soil. Biological processes include living organisms that influence the formation of soil.

Lichen (symbiotic association of algae + fungi) grows on the surface of rocks. While growing, they release certain substances that cause the rock surface to powder down and form a thin layer of soil. Other small plants like moss, are able to grow on this surface now and they cause the rock to break up further. The roots of big trees sometimes go into cracks in the rocks and as the roots grow bigger, the crack is forced bigger.