Soil Types in India
In this article, we will learn about different types of Soil in India. In our earlier post, we had covered What is Soil made of.
Here we will cover the classification and characteristics of soils of India, soil erosion and degradation, soil conservation, etc.
Major Soil Types of India
ICAR (Indian Council of Agricultural Research) has classified Indian soil on the basis of its nature and character as per the United States Department of Agriculture (USDA) Soil Taxonomy.
Classification of Soil in India
On the basis of colour, composition, genesis, and location, there are eight types of soil in India. Which are as follows:-
- Alluvial soil
- Black soil (Regur soil)
- Red and Yellow soils
- Laterite soils
- Desert soils
- Swampy or Peaty soils
- Saline soils
- Forest soils
Characteristics of soil in India
Characteristics of all eight types of soil in India are described in detail in the succeeding paragraphs.
Alluvial soil in India covers 40% of the total area.
It is mainly spread in Northern plains and the river valleys.
Alluvial soil is the most important soil for agriculture.
The silt deposition by rivers like the Indus, the Ganges, the Brahmaputra and Narmada, Tapi, Godavari, Krishna and Cauvery constitute the main feature of alluvial soil.
The Alluvial soil is divided into Khadar which is known as new alluvium and Bhangar the old alluvium.
The new alluvium is sandy and light coloured, whereas, older alluvium is clayey, dark coloured, and contains lime concretions.
Black soil is mainly found in Deccan plateau which includes parts of Maharashtra, Madhya Pradesh, Gujarat, Andhra Pradesh, and Tamil Nadu.
It is also known as regur or black cotton soils as cotton is the major crop grown in these soils.
The main characteristics of black soil are dark grey to black in colour, high swelling and shrinkage, plasticity, deep cracks during summer and poor status of organic matter, nitrogen and phosphorus.
Black soil is rich in lime, iron, magnesia and alumina.
Black soil has high water retaining capacity, rainfed crops like minor millets, pulses like coarse gram and citrus fruits are usually grown on them.
Red and Yellow Soils
These soils are derived from granite, gneiss and other metamorphic rocks.
Red and yellow soils are formed in drained condition.
The texture of red and yellow soils are high and contain low soluble salts.
These soils are slightly acidic to alkaline, well-drained with moderate permeability.
Red and yellow soils are poor in nitrogen, phosphorus, lime, and humus.
Red soils are of red colour due to the presence of ferric-oxide in the soils. They are found in the eastern and southern part of Deccan plateau.
Various crops like bajra, maize, pulses, potatoes, fruits and millets etc are grown in red and yellow soils.
Laterite means literally rock in the geological term.
These soils are rich in oxides of iron and aluminium, under the conditions of high rainfall with alternate dry and wet periods.
During rainfall iron and aluminium, oxides remain in top layers of laterite soils.
All laterite soils are poor in calcium, magnesium, nitrogen, phosphorus and potash.
Laterite soils are well-drained and porous.
Laterite soils are generally found in Karnataka, Kerala, Tamil Nadu, Madhya Pradesh, and the hilly area of Odisha and Meghalaya and Chotanagpur plateau.
On Laterite soils, rice is grown at lower elevations and tea, coffee, cinchona, rubber and cashew nut are grown in high elevations. Laterite soils are used for making bricks in house construction.
Desert soils are mainly found in North-Western part of India, like Rajasthan, South of Haryana and Punjab and Northern part of Gujarat.
These soils are derived from alluvium and are pale brown, brown to yellow-brown in colour.
These soils are structureless and fine sandy to loamy fine.
Peaty soils originate in the area of heavy rainfall.
These soils under natural conditions are thickly vegetated and swampy.
Swampy/Peaty soils are found in the foot of the Himalayas in Jammu and Kashmir, Uttarakhand, Uttar Pradesh, Bihar and Paschim Banga.
The texture of these soils varies from sandy loam to silty loam.
Swampy/Peaty soils are formed from the materials that are washed down by the erosion of mountains. They are heavy, dark and acidic. It is deficient in potash and phosphate.
- Saline soils are salt-affected soils and it is not productive in natural form.
- Almost 7 million hectares areas in a different region of India are salt-affected.
- These soils are found in the Western Ghats, deltas of the Eastern coast and in Sunderban areas of West Bengal.
- Local names of Saline soils are reh, usar, kallar, rakar and chopan.
- Farmers in Punjab and Haryana add gypsum to solve the problem of salinity in the soil.
Saline soils are formed due to accumulation of soluble salts which consists of chlorides and sulphates of calcium and magnesium.
Forest soils are formed in the forest areas.
It varies in structure and texture depending on the mountain environment where they are formed.
In snowbound areas of the Himalayas, they experience denudation and are acidic with low humus content.
Forest Soils are loamy and silty on valley sides and coarse-grained in the upper slopes.
Soil Erosion Meaning
The destruction of soil cover is known as Soil erosion. However, decrease infertility of soil is called Soil degradation.
Wind and water are the two powerful agents of soil erosion. They remove the soil and transports it from one place to another.
Soil erosion by wind is significant in arid and semi-arid regions.
In the regions with heavy rainfall and steep slopes, water plays an important role in soil erosion.
Types of Soil Erosion
There are three types of Soil erosion. Which are as follows:-
Causes and prevention of Soil Erosion
Deforestation – It is one of the major causes of soil erosion. The roots of the plants help to keep soil stronghold and thus prevent soil erosion. The soil of India is becoming saline due to overirrigation.
The use of chemical fertilizers due to the lack of organic manures is also harmful to soil fertility.
Soil conservation is a method to maintain soil fertility, prevent soil erosion and improve the degraded condition of the soil.
The method adopted for Soil conservation are as follows:-
Afforestation – is the process of planting more trees and increase the area under forest cover.
Overgrazing – of forest and grasslands by animals needs to be checked.
Construction of Dams – river floods can be prevented by constructing dams across the rivers. Consequently, it will prevent soil erosion by the river.
Crop Rotation – growing particular crop in the same field every year make it infertile. Thus it is best to grow an alternate crop in the field.
Strip Cropping – various crops are grown in alternate strips, parallel to one another. This ensures that at no time of the year the entire area is left bare or exposed.
Use of Early Maturing Variety of Crops – it takes less time to mature and thus put less pressure on the soil.
Contour Ploughing – growing crops in contour pattern, plants absorbs much of the rainwater and soil erosion is minimised.
Terrace and Contour Bunding – It is one of the oldest methods of soil conservation on hill slopes.