Page 21 - K-2184 S.St (Final) 1C P44 LITE

is alluvial soil. Alluvial soil is rich in minerals and highly fertile. So
crops grow well in it.
(d) Rice and wheat.
(e) Black soil is formed from lava or molten material that comes out of
a volcano.
(f) Laterite soil.
(g) Black soil can retain moisture for a long duration and this quality
makes this soils suitable for cultivation sugar cane and cotton.
(h) Maharashtra and Gujarat.
(i) Tea and coffee.
(j) Black soil.
(k) Rajasthan and Madhya Pradesh.
(l) Afforestation, building bunds along river banks, terrace farming and
constructing dams.
(m) Alluvial soil, black soil, red soil, laterite soil, desert soil and mountain
soil.
6. Long answer questions :
(a) The formation of soil is a long and natural process. In fact, it takes
thousands of years to form a thin layer of soil. Rocks are broken
down into smaller particles due to the forces of air, water and wind.
These smaller particles are again broken down into sand and silt.
This forms the rich, fertile surface which is called soil.
(b) Rock, wind, water influence the formation of soil. A rock rich in
minerals, forms fertile soil where as a soil formed by sand is not
suitable for agriculture.
(c) Black soil is formed from lava or molten material that comes out of
a volcano. It is generally clayey, deep and impermeable. This soil can
retain moisture for a long duration and this quality makes the soil
suitable for cultivation. Black soil is found in the state of Madhya
Pradesh, Maharashtra, Gujarat, Andhra Pradesh and Tamil Nadu.
(d) We can preserve the fertility of the soil by retaining or increasing
natural fertilisers like compost instead of chemical fertilisers.
(e) Following are some ways of conserving soil :
(i) By afforestation that is planting more and more trees.
(ii) By building bunds along river banks.
(iii) Growing plants along the mountain slopes in layers.
(iv) By constructing dams across the river to check the speed of water.
(v) By crop rotation.
(f) Washing of loose soil by water and wind is called soil erosion. Soil
erosion can be prevented by in following ways :
(i) By afforestation that is planting more and more trees.
(ii) By building bunds along river banks.
(iii) Growing plants along the mountain slopes in layers.
(iv) By constructing dams across the river to check the speed of water.
(v) By crop rotation.

Social Science (21) Class–4