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Ÿ The three different layers of soil are top soil, subsoil and bed soil.
Ÿ Strong winds, rains, floods and man’s activities cause soil erosion.
Ÿ Soil can be conserved by growing grass, plants and trees.

Points to Remember

Humus : the organic component of soil,

Organism : a living thing that can function on its own

Soil Conservation : Protecting soil from being carried away by wind and water

E XE R C I S E

A. Tick (ü) the correct answer.
1. Plants grow in soil/river.
2. The uppermost layer of soil is called topsoil/subsoil.
3. Soil erosion reduces/increases the fertility of soil.
4. The soil below the top soil is subsoil/bedsoil.

B. Fill in the blanks.

1. Soil is important for all ......................

2. There are .................... main layers of soil.

3. The process of carrying away the topsoil by wind or flowing water is known as
..............................

4. ................... is the most fertile layer of the earth, as it has nutrients in it.

5. .................... takes thousands of years to develop.

C. Match the following column.

Column A Column B

1. Growing grass a) Terrace farming

2. Hilly regions b) Embankments

3. Growing trees c) Plains

4. River banks d) Afforestation

D. Put a (ü) tick for correct and (û) cross for wrong statements.

1. Terrace farming is done in plains.

2. Overgrazing causes soil erosion.

3. Embankments are done on rivers to avoid soil erosion.

4. Deforestation increases soil fertility.

5. Growing grass in open fields reduces soil erosion.

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