Soil


Soil is an important natural resource as it provides growth of plants, provides food and shelter and many more. If soil is in rock form, it becomes difficult to use it for different purposes. A natural process of weathering takes place to convert rocks into fine particles called soil.

Process of Soil Formation

Sun

Due to heat of sun, rocks expand during the day time. As temperature becomes low at night, these rocks undergo contraction. Expansion and contraction of rock occurs at different rate. Due to which, cracks are formed. Thus,it results in breaking of rocks, and ultimately forms soil.

Water

If water enters into the cracks of rocks, during the night, due to low temperature, it freezes. as a result, crack in rock widens, thereby, resulting into breaking of rock and forming a soil. Flowing water carries big and small rocks. While flowing they rub with each causing damage. Hence, causes breaking of rock forming the soil.

Wind

Wind follow similar procedure as that of water. It carry rocks, these rocks rub with each other, thereby causing breakage of rocks.

Living organisms

Living organisms like lichens, moss are also responsible for soil formation. Lichens grow on rock surface, and secrete substances which makes rock surface powdery. Moreover, when moss grow on this surface, it facilitates more breaking. Also, roots of plants when penetrates into the rock it allows breaking of rock in fine particles thereby converting it into soil.



Soil Quality

soil

Quality of soil

Quality of soil is said to be good if it contains essential nutrients and large amount of humus. Presence of good quantity of humus makes the soil porous, helps in absorption of water deep into the soil.

Soil Pollution

Due to excessive use of insecticides and pesticides, microorganisms and earthworms die. This leads to decrease in production of humus. Continuous decrease make the soil lack with these necessary factors. Damage caused to soil due to chemical which shows reverse effect on soil is called soil pollution.

Soil erosion

Due to wind or water, soil gets carried away, leading to the exposure of rock beneath the soil. This is soil erosion. Reason behind the soil erosion is growth in cutting of trees. To prevent soil erosion it is necessary to plant trees. As roots of trees have firm grip on soil, it prevents soil to get carried away with wind or water.

Watch video on Soil here

Keywords: Weathering, Soil formation, Soil pollution, Soil erosion, Soil quality, Topsoil.

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