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Soil Formation, Erosion
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Grow and Conservation
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l Usefulness of soil
l The process of soil formation
Inside l Soil erosion
Inside
the l Erosion by wind, water and human activities
the
Chapter l Soil conservation
Chapter
l Growing Grains, Building Dams, Afforestation, Terrace Farming
l Soil pollution

SOIL
Ground level
Soil is the uppermost layer of the Earth’s
crust. It consists of a mixture of minute Top soil

particles of rocks, minerals, dust and
remains of dead plants and animals. It also
Sub soil
contains air and water.
Soil is very useful for all living things. In

fact, life on land depends on soil. It
supports the growth of plants. We all are
Weathered
dependent on plants for our basic needs parent rock

like food, clothing and shelter. Soil is also
the home for many organisms like bacteria,
Bedrock
fungi, worms and insects.

One Step Ahead
One Step AheadOne Step AheadOne Step AheadOne Step AheadOne Step Ahead FORMATION OF SOIL
One Step AheadOne Step AheadOne Step AheadOne Step AheadOne Step Ahead
One Step Ahead
Natural forces like wind, The formation of soil happens over a very long
rain and running water period of time. The process by which soil
help in soil formation.
formation takes place is called weathering .

Weathering is a very slow and gradual process during which the parent rock

breaks down into fine particles. The large rocks are initially broken down into
small pieces by natural events like earthquakes. The process of weathering is

carried further by other agents like temperature changes, frost, water, wind
and living organisms. It takes 200 to 400 years for the formation of just 1 cm

of topsoil.
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