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This process by which the top layer of soil is removed is known as soil erosion. Soil

erosion reduces the fertility of soil. We must take necessary steps to conserve soil.
Trees or plants hold the top layer of soil with their roots. Thus, we should check

deforestation and plant more trees.
Farmers must use natural fertilisers

such as cow dung and compost because
chemical fertilisers are harmful for the

soil. Growing some crop in a particular
area for a long time reduces the soil

fertility. Therefore, farmers must grow
different crops one after another on

the same land. Soil is necessary for our
food requirements. Therefore, it should

be conserved. Roots of trees and plants hold the top layer of the
soil and help in preventing erosion.
Mineral Resources

You have read that rocks and soil contain one or more minerals. But what are
minerals? Minerals are substances that are naturally present in the Earth and are
used by us for our various needs. Minerals that are found deep underneath the

Earth’s surface are dug out through huge holes. These holes are called mines. The

process of digging minerals is called mining.

Metallic and Non-metallic Minerals

Minerals are of two types–metallic minerals and non- metallic minerals. The minerals

from which we get metals are called metallic minerals. Metals are hard, usually
shiny substance that exist naturally in the Earth. Iron, copper, gold, silver, tin and

aluminium are examples of metals. Many things that you see around you, such
as door knobs, latches, utensils, bridges and scissors are all made out of metallic

minerals.

All minerals are not metals. There are some minerals such as limestone, mica, coal,
salt, diamond, mineral oil or petroleum and natural gas which are non-metallic

minerals. They are not hard and do not shine.

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