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The important natural resources available on Earth are land, water and air.
The region of Earth where the atmosphere, hydrosphere and lithosphere interact and support life is called biosphere.
Living organisms constitute the biotic component of the biosphere. Air, water and soil constitute the abiotic component of the biosphere.
Air is a mixture of gases like nitrogen, oxygen and carbon dioxide.
Plants and animals use oxygen for respiration, carbon dioxide is used by plants for photosynthesis are the uses of air.
Experiment -role of air in climate control: concludes that soil gets colder faster than water and air.
Why is the land near water bodies cool? - During the day, heated air above the land causes air to move from the sea to the land and making the land near water bodies colder.
At night, air moves from land to the sea, creating a land breeze.
When the temperature is low, precipitation may occur in the form of snow, sleet or hail.
In India, rain is brought by monsoons and are of two types namely south-west and north-east.
Contamination of air is called air pollution.
Fresh water is found on snow-covered mountains, in rivers and lakes. Saline water is found in seas and oceans.
Contamination of water is called water pollution.
Industry chemicals, urban sewage and pesticides are the causes of water pollution.
Soil contains soil particles, humus and living organisms.
Sun, water, wind and living organisms help in formation of soil.
The addition of substances that adversely affect soil fertility is called soil pollution.