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Here, the land refers to the lithosphere, while air and water indicates atmosphere and

hydrosphere respectively. The plants and animals are the major parts of the biosphere. Let
us recapitulate all these four domains of the earth to understand our environment well.

major sphErEs of EnvironmEnt

Corresponding to the elements of environment, there are four different spheres of
environment.

i. atmosphErE
The atmosphere is the body of air which surrounds our planet. Most of our atmosphere is
located close to the earth’s surface where it is most dense. The air of our planet is 79%
nitrogen and just under 21% oxygen; the small amount remaining is composed of carbon
dioxide and other gases.

All four spheres can be and often are present in a single location. For example, a piece of

soil will of course have mineral material from the lithosphere.
Additionally, there will be elements of the hydrosphere present as moisture within the soil.

ii. lithosphErE
• It is the solid crust or the hard top layer of the earth.

• Lithosphere has many ups and downs. It consists of different types of landscape such
as mountains, plateaus, hills, valleys, etc.
• These landscape are found over the continents and ocean floors.

• The lithosphere is made up of various rocks and minerals.
• The lithosphere is covered with thin layer of soil.

• The soil helps to grow different types of plants and shrubs, which provide food not
only to human beings but for the animals also.
• The lithosphere is also known as the home of different plants and animals.

• It is a source of various mineral resources such as coal, aluminium, manganese, lead,
zinc, oil, etc.
• It provides land for growing crops and human settlement.

iii. hydrosphErE

The hydrosphere is composed of all of the water on or near
the earth. This includes the oceans, rivers, lakes and even

the moisture in the air. Ninety seven percent of the earth’s
water is in the oceans.

The remaining three percent is fresh water. Three quarters

of the fresh water is solid and exists in ice sheets.
Domains of the Environment

Social Studies
6 6 Social Studies-7-7