The depositional works of running water form the soil. They are mainly found along the river banks, deltas, estuaries and streams. It is the most fertile soil. Wheat, rice, maize, sugarcane, pulses, oilseed are the commonly cultivated crops.
Red soils are formed by the weathering of igneous and metamorphic rocks in regions of low rainfall. The red colour is due to the presence of iron oxide. The productivity of the soil increases with the addition of fertilisers. Bajra, maize, pulses are commonly grown crops.
Black soil is formed due to the weathering of volcanic rocks. It is ideal for the cultivation of cotton and is called ‘Black cotton soil’. The soil has high clay content. It retains the moisture for a very long time and is suitable for crop cultivation even in a dry season.
These soils are found in areas of high temperature and heavy rainfall. The soils are formed due to the leaching of heavy tropical rains. Since the minerals are leached away generally, the soil is infertile. The soil is poor in organic content. It is ideal for the plantation crop such as tea, coffee, etc.
These are soil found on the slopes of the mountains. The soil is rich in humus, but the mineral content is low. The soil is acidic in nature. The profile of the soil is not well developed, and the characteristics of the soil vary from region to region depending upon the altitude.
The soil found in the desert region formed by the depositional activity of wind. They are highly saline and porous in nature. The humus content is very low. Only drought-resistant and salt-tolerant crops can be grown here.