Question

answer in brief how does biological weathering occur

Answer 1

there are two main type:

mechanical and chemical. biological weathering isn't really a process but living organisms can cause both mechanical and chemical weathering to occur for eg- trees roots can grow into fractures in a rock and prytehe rock apart , causing mechanical fracturing

Answer 2

ANSWER:

Biological weathering occurs with the help of living organisms like lichens, and plants.

EXPLANATION:  

Weathering is a process in which large pieces of rocks are broken down in small pieces and is finally converted into small particles which gets ultimately converted to soil in millions of years. When this process of weathering is done by living organisms then it is called as biological weathering.

The first living organism that starts it is lichens. It is the symbiotic association of algae and fungi, the fungi release chemicals which causes breakouts in the small portions of rocks and later these crevices in the rocks provides space for the penetration of roots of other plants. Lichens are succeeded by bushes and scrubs and later on by large trees. This is the biological weathering which usually takes thousands of years.