How is soil formed, Science

Assignment Help:

Q.How is soil formed?

Soil is formed by breaking down of rocks at or near the surface of the Earth through various physical, chemical, and biological processes by various factors such as the sun, water, wind, and living organisms.

(i) Sun:

During day time, the rocks are heated. This causes the rocks to expand. During night time, these rocks cool down and contract. Since all parts of the rock do not undergo expansion and contraction at the same rate, this causes the formation of cracks in these rocks. These cracks lead to the breaking up of huge rocks into smaller pieces.

(ii) Water:

Water catalyses the process of formation of soil in two ways.

(a) Water goes into the cracks and crevices formed in the rocks. When this water freezes, its volume increases. As a result, the size of the cracks also increases. This helps in the weathering of rocks.

(b) Running water wears away hard rocks over long periods of time. Water moving in fast speed carries big and small particles of rock downstream. These rocks rub against each other, resulting in breaking down of rocks. These smaller particles are carried away by running water and deposited down its path.

(iii) Wind:

Strong winds carry away rocks, which causes rubbing of rocks. This results in the breaking down of rocks into smaller and smaller particles.

(iv) Living organisms:

Some living organisms like lichens help in the formation of soil. Lichens also grow on rocks. During their growth, lichens release certain substances, which cause the rock surface to powder down forming a thin layer of soil. On this thin layer of soil, some small plants like moss also grow. They further cause the breaking down of the rock particles.


Related Discussions:- How is soil formed

What is tocopherols, What is  tocopherols Vitamin  E  refers  to a  gr...

What is  tocopherols Vitamin  E  refers  to a  group  of  compounds known  as  which  are the derivatives of a parent compound called as  'tocol'. Four tocopherols namely a, P,

The property of cleavage, Which  minerals best illustrates the property of ...

Which  minerals best illustrates the property of cleavage: Mica

Describe the term - phosphate deficiency, Leguminous crop grown under phos...

Leguminous crop grown under phosphate deficiency conditions may suffer from N deficiency as well.  Explain. Rhizobium bacteria infect the roots of leguminous plants and lead to

Explain the alpha fetoprotein screening (afp), Explain the Alpha Fetoprotei...

Explain the Alpha Fetoprotein Screening (AFP) This is a blood test that measures the level of alpha-fetoprotein in the mothers' blood during pregnancy. AFP is a protein normall

Define the role of bacteria in soil flora, Define the role of Bacteria in s...

Define the role of Bacteria in soil flora The most abundant soil organisms are primitive, very minute, unicellular organisms devoid of chlorophyll. Bacteria are most abundant i

Geocentric universe of the ancients, Geocentric Universe of  the Ancients:...

Geocentric Universe of  the Ancients: The  earliest ideas of  the Egyptians and Sumerians about the universe may seem strangeto us. The Earth appeared flat 2nd solid tg them.

First aid procedures, First Aid Procedures :   Your Counsellor will explain...

First Aid Procedures :   Your Counsellor will explain the first aid procedures through a demonstration session. Carefully observe ali the steps. Try to relate the contents of the f

Define hypoparathyroidism, Define Hypoparathyroidism Hypoparathyroidism...

Define Hypoparathyroidism Hypoparathyroidism or a decrease in the secretion of parathormone causes an upset in calcium metabolism. Hypocalcemia develops and the muscles go into

Define erythroblastosis fetalis, Define Erythroblastosis Fetalis Beside...

Define Erythroblastosis Fetalis Besides the risk of a mismatch reaction during a second or during any subsequent  blood transfusion, giving Rh-positive, blood involves  risk in

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd