Fill in the blanks
1. …………. are classified on the basis of their colour climate, parenteral rocks, structure and humus, etc.
2. Alluvial soil contains about …………… of total surface area of India.
3. The red colour of red soil is due to ……………. in it.
4. Black soil is formed due to the spreading of Deccan …………. .
5. In the formation of …………… the role of lava rocks and climate is important.