Question

What do you mean by biological weathering? Give two examples.

Answer 1

Biological weathering refers to the breakdown of large rocks into smaller minerals by living organisms. This process is responsible for the formation of soil. Two particular examples of biological weathering includes weathering induced by bryophytes and lichens.

Lichens induce biological weathering by extracting minerals from the rocks, which results in the formation of small cervices that serve as the site for soil formation.

Bryophytes can readily grow in the cervices formed by lichens and further deepen the cervices. These deeper cervices form cracks. In due course of time, because of growth of bigger plants, rocks eventually pulverise and form soil.