Soil is the name for the top layer of earth. Typically, soil is softer than the rocky layers beneath it. It is also usually of a black or brown hue. It is made up of smaller particles, which clump together when wet. Soil is nutritious and rich in minerals – and as such plants need it to survive.
Types of Soils in India
Soil is a valuable resource of India. Much of the Indian agriculture depends upon the extent and qualities of soil. Weathering prepares loose materials on the surface of the Earth and mixed with decayed organic matters it forms soil.
India is a large country and witnesses diverse range of climatic and other natural conditions. The nature of soil in a place is largely influenced by such factors as climate, natural vegetation and rocks.
The various types of soil found in India includes Alluvial soil, Laterite soil, Red soil, Black soil, Desert soil, and Mountain soil. They are each discussed below.
Major types and characteristics of soils in India:
Indian soils may be divided into six major types based on their character and origin:
1. Alluvial soil: Materials deposited by rivers, winds, glaciers and sea waves are called alluvium and soils made up of alluvium are alluvial soils. In India alluvial soils are mainly found on the Indo-Ganga Brahmaputra Plains, Coastal Plains and the broad river valleys of South India. They are also found along the river basins of some plateau and mountain regions.
In the Indo-Ganga plain two other types of alluvium are found. The old alluviums are clayey and sticky, have a darker color, contain nodules of lime concretions and are found to lie on slightly elevated lands. The new alluviums are lighter in color and occur in the deltas and the flood plains.
In comparison to old alluvial soil, the new alluvial soils are very fertile. The alluvial soil is regarded as the best soil of India for its high fertility and the rich harvest, it gives rice, wheat, sugarcane, jute oil-seeds and pulses are the main crops grown on this soil.
Also read: Alluvial Soils in India
2. Laterite and Lateritic soils: Laterite is a kind of clayey rock or soil formed under high temperature and high rainfall. By further modification laterite is converted into red colored lateritic soils charged with iron nodules. Laterite and lateritic soils are found in South Maharashtra, the Western Ghats in Kerala and Karnataka, at places on the Eastern Ghat, in some parts of Assam, Tamil Nadu, Karnataka, and in western West Bengal (particularly in Birbhum district). These soils are generally infertile. Some plants like tea, coffee, coconut, areca nut, etc. are grown in this soil.
Also read: Short note on Laterite Soil in India
3. Red Soils: Red soils develop on granite and geneses rocks under low rainfall condition. The dissemination of red oxides of iron gives the characteristic red color of the soil. These soils are friable and medium fertile and found mainly in almost whole of Tamil Nadu, South-eastern Karnataka, North-eastern and South-eastern Madhya Pradesh, Jharkhand the major parts of Orissa, and the Hills and Plateaus of North-east India. But these have capacity to grow good crops after taking help of irrigation and fertilizers. Wheat, rice, millets, gram, pulses, oil-seeds and cotton are cultivated here.
Also read: Red Soil in India
4. Black Soils or Regur soils: The regur or black soils have developed extensively upon the Lava Plateaus of Maharashtra, Gujarat, Madhya Pradesh mainly Malwa. Black soils have also developed on gneisses of north Karnataka and north and west of Andhra Pradesh. The regur is clayey, becomes very sticky when wet. Its special merit lies in its water holding capacity. These soils are very fertile and contain a high percentage of lime and a moderate amount of potash. The type of soil is specially suited to the cultivation of cotton and hence sometimes called ‘black cotton soil.’ Sugarcane, wheat, and groundnut are also cultivated.
5. Desert soil: The soils of Rajasthan, Haryana and the South Punjab are sandy. In the absence of sufficient wash by rain water soils have become saline and rather unfit for cultivation. In spite of that cultivation can be carried on with the help of modern irrigation. Wheat, bajra, groundnut, etc. can be grown in this soil.
This soil type is more gritty and feels more like sand. It usually drains well but does not contain so many nutrients as other types of soil. It can also shift and blow away with the wind, too, unlike clayey soil which tends to clump together in one place. This is because sandy soil is one of the lightest types of soil.
6. Mountain soil: Soils are varied in mountains. Alluvium is found at the valley floor, brown soil, rich in organic matter, in an altitudinal zone lying between about 700-1800 m. Further up podzol soils, grey in color and acidic in reaction, are found associated with coniferous vegetation. In the Alpine forest belts the soils are thin and darker in color. This type of soil is suitable for the cultivation of potatoes, fruits, tea coffee and spices and wheat.
Also read: Short notes on Mountain Soil in India
Edited with inputs from various contributors.