GK Question “What Do You Know About Formation Of Soil?” general knowledge book English 2021 current affairs quiz and answers for class 7, 8

What Do You Know About Formation Of Soil?

In the absence of a cover over the earth the existence of man would have not been possible. Plants could have not grown. Food for human beings and animals would have not been available.

Soil is powdery earth, loose in the state, in which plants grow. Decayed plant and animal life, and small pieces of rock compose soil. The large rocks weather and disintegrate into small pieces or particles. The animal and plant material have origin in animal bodies and plants. No rock is hard, as not to get broken in time. The crumbling and wearing of rocks is a continuous process. Glaciers push piles of rock and thus this grinding helps crumble the rocks.

Water and chemicals dissolve the rocks and cause wear. The temperature changes and fluctuations break the rock into pieces. The heating and cooling produce cracks. Water getting into cracks, freezes, swells and causes further disintegration. Plants take root in soft pockets and split the rocks. The wind is another agent to inflict injury by hurling sand against rock a-id to help it crumble.

The making of the soil starts like this. To enrich the coil with crime properties, ‘humus’ must be added to sand or time particles of rock. Humus is an organic material, with plants and animal life as the origin. Bacteria turn dead land plants and animals into the soil. This makes the soil fertile. Earthworms and many other insects help to make the soil rich. The ‘topsoil’ is the richest layer of soil and contains much humus. The under layer or ‘subsoil’ contains pieces of rock. The layer further down below is the bedrock and is under the soil every-where.