Soil Types of India

USDA soil texture chart
India has a variety of soil types ranging from the most fertile alluvial soils to infertile saline and alkaline soils. The formation of different soil types depends on the parent rocks, climatic conditions, topography, relief features and the natural vegetation. 
Soil Types of India

-Dr. Arvind Singh

Soil is the weathered superficial layer of the Earth’s crust which serves as a natural medium for the growth of plants. Soil is one of the most important ecological factors. Plants depend for their nutrients, water supply and anchorage upon the soil. The components of soils include mineral material, organic matter, water and air the proportions of which vary and which together form a system of plant growth. Being a vast country India has a variety of soil types. These varieties in soil types are a consequence of the diversity in natural environment.

The variations in nature of the soil are mainly related to the parent rocks, surface or relief, the general pattern of the slope, climate and the natural vegetation. On the basis of their nature and composition Indian Council of Agricultural Research (ICAR) has divided the soils of India into eight different types which are described as follows:

1. Alluvial Soils:
The alluvial soils include the deltaic alluvium, calcareous alluvial soils, coastal alluvium and coastal sands. This is by far the largest and most important soil group of India contributing the largest share to it agricultural wealth. In fact, alluvial soils are the backbone of Indian economy. They occupy about 15 lakh km square of land area. Alluvial soils occur chiefly in the Indo-Gangetic plain covering the states of Punjab and Haryana in North-west, Uttar Pradesh and Bihar in the North, and West Bengal and parts of Meghalaya and Odisha in the North-east. Alluvial soils are generally made up of fine silt brought down by rivers from the mountains.

The alluvial soils vary from sandy loam to clayey in texture. In the Ganges- Brahmaputra plains soil contains very fine particles varying from loams to very fine silt clay. The soil is generally alkaline or neutral in reaction. Alluvial soils are generally poor in nitrogen and phosphorus but rich in potash.

Geologically the alluvial soils of North Indian Plains are divided into ‘khadar’ and ‘bangar’. The khadar is newly formed alluvium and is most fertile while the bangar is old alluvium and largely contains clay particles. Alluvial soils are most suitable for the cultivation of paddy, wheat, maize and barley.

2. Black Soils:
Black soil which is also known as ‘regur’ soil is distributed over the Deccan lava tract which extends over parts of Maharashtra, Madhya Pradesh, Gujarat, Andhra Pradesh, Karnataka and Tamil Nadu. The black colour is due to the presence of titaniferous magnetite. These soils cover an area of about 5.46 lakh km square. Black soils are predominantly clay with patches of clay loams, loams and sandy loams.

Black soil varies in depth from shallow to deep. It is derived from two types of rocks, the Deccan and Rajmahal trap and ferruginous gneisses and schists occurring in Tamil Nadu state in under semi-arid conditions. The former attains considerable depth whereas the latter are generally shallow.

Black soils are highly argillaceous very fine-grained, dark and contain a high proportion of calcium and magnesium carbonates. They are very tenacious of moisture and exceedingly sticky when wet. Owing to considerable contraction on drying large and deep cracks are formed. 

These soils contain abundant iron and fairly high quantities of lime, magnesia and alumina. Black soils are poor in phosphorus, nitrogen and organic matter. The soils are generally rich in montmorillonite and beidellite group of clay minerals. Black soils are most suitable for the cotton crop hence it is also known as ‘black cotton soil’. In addition to cotton, the soil is suitable for the cultivation of crops like wheat, groundnut, chillies, tobacco and jowar.

3. Laterite Soils:
Laterite soils are formed under typical monsoonal conditions with alternating wet and dry seasons. During heavy rains, a siliceous matter of rocks get dissolved in water and ultimately washed away leading to the formation of laterite soils. This process is known as lateralization. These soils have porous clay rich in hydroxides of iron and aluminium.

Laterite soils are deficient in lime, phosphorus, potash, nitrogen and magnesium hence they are poor infertility. They are generally acidic in nature. 

Laterite soils are found in states of Karnataka, Kerala, Tamil Nadu, Andhra Pradesh, Maharashtra, Madhya Pradesh, Odisha and Assam. 

Laterite soils at lower elevations are suitable for paddy cultivation while those at higher elevations favour the growth of tea, coffee, rubber and cinchona. 

4. Red Soils:
Red soils cover a large area in South and North-east of the peninsula. Such soils occur in Tamil Nadu, Eastern Andhra Pradesh, Karnataka, Goa, South-eastern Maharashtra, Madhya Pradesh and parts of Jharkhand, Odisha, Uttar Pradesh and West Bengal. Red soils cover an area of about 90,000 km square. The ancient crystalline and metamorphic rocks on meteoric weathering have given rise to red soils. Red soils have reddish colour which is due to the presence of iron in the crystalline and metamorphic rocks. Red soils are mainly sandy to loam in texture, with gravels on upper slopes, then sandy soils, deeper loamy soils on slopes and loams or rather clay in the valley bottoms.

In general red soils are porous and airy and need irrigation support for cultivation. These soils are deficient in nitrogen, phosphorus, potash and humus. Red soils are suitable for cultivation of crops like paddy, ragi and tobacco.

5. Mountain Soils:
Mountain soils are distributed in Vindhyan, Satpura, Nilgiri and Cardamom hills, and the slopes of Himalayas. They are also called as forest soils. These soils are suited for the growth of the forest. Mountain soils are rich in humus and nitrogen but are deficient in potash. They are acidic in nature. Mountain soils are suitable for the cultivation of tea, coffee, spices and fruits.

6. Desert Soils:
Desert soils contain a high percentage of soluble salts and are poor in organic matter. These soils are light in colour. Desert soils are found in Northwestern India. These type of soils cover the entire areas West of Aravallis in Rajasthan and part of Haryana, Punjab and Gujarat. Desert soils are rich in phosphorus but poor in nitrogen. The water holding capacity of desert soil is very poor due to lack of humus. Desert soils are suitable for the cultivation of millets. 

7. Peaty and Marshy Soils:
These soils are developed under humid conditions as a result of the accumulation of a large amount of organic matter and a considerable amount of soluble salts. Peaty soils are rich in organic matter but deficient in phosphorus and potash. They are found in Allepey in Kerala. Marshy soils are found in the coastal tracts of Odisha, Sunderbans, North Bihar and in the Almora district of Uttarakhand. Peaty soils are not suitable for cultivation. 

8. Saline and Alkaline Soils:
Saline and alkaline soils have sodium, calcium and magnesium salt encrustations on the surface. These soils are found in drier tracts of Uttar Pradesh, Bihar, Haryana, Punjab and Rajasthan. Saline and alkaline soils are locally called by different names like ‘Reh’, ‘Kallar’, ‘Usar’ ‘Chopan’ ‘Kari’ and ‘Thur’.

Saline and alkaline soils are also found in waterlogged areas of canal irrigation and areas of the high water table. Underground salts are drawn upward due to capillary action.

Owing to accumulation of high salt concentration these soil types are not conducive for cultivation hence they are also called as ‘problem soils’. 

Finally, it can be concluded that India has a variety of soil types ranging from the most fertile alluvial soils to infertile saline and alkaline soils. The formation of different soil types depends on the parent rocks, climatic conditions, topography, relief features and the natural vegetation. The fertile alluvial soils cover the maximum area among the different soil types of India.

Dr. Arvind Singh is M.Sc. and Ph.D. in Botany with area of specialization in Ecology. He is a dedicated researcher having five dozens of published research papers to his credit in journals of national and international repute. His main area of research is ecological restoration of mine spoils. However, he has also conducted research on the vascular flora of Banaras Hindu University main campus and the vascular wall flora of Varanasi city. Furthermore, Dr. Singh is an active science writer having more than ten dozens of published science articles to his credit in different periodicals of national repute. His electronic address is keywords: different types of soil in india, different types of soil found in india, major types of soil found in india, soil distribution in india, major types of soil, alluvial soil in india, soil classification in india, how many type of soil in india, soil types in india, soil types classification, different soil types, soil types construction, soil types and testing, soil layers, soil types for kids