Facts that Matter
Acts as a protective blanket around the earth. Maintains the temperature on the surface of earth. Winds are caused due to uneven heating of atmosphere, these winds maintains the pressure difference and causes cold and hot air, sea and land breeze, brings rain etc.
It consists of biotic components–living things and abiotic components–non living things like air, water and soil.
Use of Water
— Water is used for transportation.
— Sustain life
— Used by plants and animals for life-processes. Water available for drinking should be conserved and used wisely.
Varieties of soil are:
1. Sandy soil
2. Loamy soil
3. Clayey soil
4. Black soil
5. Red soil
6. Alluvial soil
7. Laterite soil.
Nitrogen from the atmosphere is fixed by the process of nitrification. Nitrification is done by nitrogen fixing bacteria e.g. Rhizobium present in soil, these compounds of nitrogen are absorbed by plants. The fixation is also done by atmosphere or industries. In atmosphere, during lightning, high temperatures and pressures created in air convert nitrogen into oxides of nitrogen, which dissolves in water forming nitric and nitrous acids and is then used by life forms.
Plants contain nitrogen in the form of proteins or other complex compounds. Plants are eaten by animals. When dead bacteria present in soil act on and convert plants and animals of various compounds of nitrogen into nitrates and nitrities. Another group of bacteria convert these nitrates and nitrites into free, elemental nitrogen, this process is called denitrification.
CO2 is taken by plants during photosynthesis to form organic compounds like glucose, carbohydrates. These plants are further eaten by animals and decomposition gives CO2 back to atmosphere. Plants and animals which get buried under the earth and does not decompose form coal and petroleum respectively.
Animals and plants also release CO2 back to atmosphere during respiration.
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1. What are natural resources? |
2. What are some examples of renewable natural resources? |
3. What are non-renewable natural resources? |
4. How can we conserve natural resources? |
5. What are the consequences of overexploiting natural resources? |
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