The removal of soil at a greater rate than its replacement by natural agencies (water, wind etc.) is known as soil erosion.
Soil erosion is of four types: wind erosion, sheet erosion, rill erosion and gully erosion.
Winds carry away a vast quantity of fine soil particles and sand from deserts and spread it over adjoining cultivated land and thus destroy their fertility.
This type of erosion is known as wind erosion.
It takes place in and around all desert regions of the world.
In India, over one lakh kilometers of land is under the Thar Desert, spread over parts of Gujarat, Haryana, Punjab and Rajasthan states.
These areas are subject to intense wind erosion.
Water when moves as a sheet take away thin layers of soil.
This type of erosion is called sheet erosion.
Such type of erosion is most common along the river beds and areas affected by floods.
In the long run, the soil is completely exhausted due to removal of top soil and becomes infertile.
The removal of surface material usually soil, by the action of running water.
The processes create numerous tiny channels (rills) a few centimeters in depth, most of which carry water only during storms.
When water moves as a channel down the slope, it scoops out the soil and forms gullies which gradually multiply and in the long run spread over a wide area.
This type of erosion is called gully erosion.
The land thus dissected is called Bad Lands or ravines.
In India, the two rivers Chambal and Yamuna are famous for their ravines in U.P. and M.P. states.