Soil is defined as the organic materials and inorganic materials on the Earth’s surface that provides the medium for the plant growth.
Types of soil in India
In India, there are mainly six type of soil found :-
1. Alluvial soils
2. Black soils
3. Red soils
4. Laterite soils
5. Desert soils and
6. Mountain soils
1. Alluvial soils
Alluvial soil are fertile soil which is mainly deposited by rivers on and near the river region. Alluvial soils are mainly found in the northern plains of the India. Alluvial soils covers almost 40-45% of the region of India. It covers about 143 lakh square kilometers of the total geographical area of India.
Ganga region is the most fertile reason of Alluvial soil, it is deposited by ganga river. Alluvial soil are very rich in minerals, they contains high potash. This type of soil are well suitable for agriculture but it is poor in phosphorus.
There are mainly two types of Alluvial soil found in India :-
Khadar and Bhangar
Khadar is the type of Alluvial soil which is deposited by flood which enriches the soil by depositing fine silts.
Bhangar, it is the type of old Alluvial soil which is deposited away from the flood plains.
Khadar and Bhangar soils contains calcaveous concretion. The colour of alluvial soil varies from light grey to grey and its shades depend upon the depth of deposition.
Rice, wheat, sugarcane, oilseeds, pulses are the main crops which grow well in the Alluvial soil. It is the most type of soil which is found in India.
It is found apart from rivers regions, in the northern plain beginning from Punjab to West Bengal and Assam. Alluvial soil is also found in the deltas of rivers such as Krishna, Godavari and Kaveri in peninsular India.
2. Black soils
Black soil is a type of soil which is made up of volcano rocks and Lava. The black soil is also known as regur which comes from the Telugu word called reguda. Cotton is an important crop which is well grown in the black soil and hence it is also known as Black cotton soil. The black soil is rich in calcium carbonate, lime and magnesium carbonate but poor in phosphorus.
Black soil is mainly found in Maharashtra, Gujarat and Madhya Pradesh. The texture of black soil is extremely fine and clayey and it has the capacity to hold a good amount of water in the season of rainy. It becomes sticky and develop crackey when it is summer season. Cotton, oil seed, wheat, millets, tobacco are the Some crops which is well suitable for the black soil and grow better.
There are some theories has been put forward regarding the origin of this group of the soil but most of the scientist believe that the black soil have been formed because of the solidification of lava.
The colour of black soil vary from deep black to light and chestnut and it is dependent on the colour of the mechanical fraction. The colour black or black soil is attributed to the presence of titanosaurus magnetite and aluminium accumulated, humus, colloidal hydrated iron and aluminium silicate. This type of soils are highly retentive of moisture, highly compact and tenacious when wet.
3. Red soils
This type of soil formed by weathering of crystalline and metamorphic rocks. The colour of red soil is red due to the high iron content. The red soil are found in the areas of low rainfall and hence it is less leached. Red soil are sandier and very less clayey soil. It is poor in phosphorus, nitrogen and lime. Red soil cover the high region almost 3.5 Lakh sq km of the total geographical area of India.
Red soil is mainly found in Tamil Nadu, Karnataka, North East Andhra Pradesh and some part of the Madhya Pradesh, Chhattisgarh and odhisa. Wheat rice, cotton, sugarcane and pulses are the crops which grow well in red soil.
The texture of red soil varies from sandy to clay. Red soil is also known as yellow soil in some part of the India it is just because of the high concentration of iron oxide and iron is responsible for giving this soil it’s reddish and yellowish shades. The red soil are poor gravelly and Porous on the upland but rich and fertile in the lower region.
Red soil covers about 3.5 lakh kilometre of the land of the total area of India. About 10.6 percent of the total land of India is covered with red soils. Red soil have thin layer and are less fertile. The red soil is divided into four categories namely red soil, red gravelly soil, red and yellow soil and mixed red and black soil. The pH of red soil is ranging from neutral to acidic.
4. Laterite soil
Laterite soil is rich in iron and aluminium which is formed in wet and hot tropical region. Meaning of laterite soil is brick in Latin. Laterite soil are red in colour because of the presence of iron and aluminium oxide.
Laterite soil is mainly found in western coastal region and mid part of the India. It is also found in the area along with the edge of the plateau in the east which covers small part of the state like Tamilnadu, Odisha and Jharkhand.
This type of soil are poor and can hold only scrub forest. The laterite soil is acidic due to the poor concentration of lime. Humus in the laterite soil is almost absent. Simply we can say that laterite soil are mostly the end product of weathering.
Laterite soil are formed under the condition of high temperature and high rainfall. In India, laterite soil covers about 2.48 lakh square kilometre area of the total geographical area of India. Laterite soil is less fertile due to intensive leaching. The main crop which is grow in the laterite soil is tea, coffee, rubber, coconut etc.
Laterite soils provide a valuable building material and this are easily cut into the piece but harden like iron when exposed to the air. Organic material of laterite soil will be removed first by bacteria because it is high temperature and humus will be taken quickly by the trees and crops. The humus content is low in the leterite soil.
5. Desert soils
Desert soils are basically of Sandy texture. Desert soil have poor clay content and it has lack of moisture content. This type of soil are generally of brown and light brown and reddish colour.
Leaching of desert soil is almost absent because of the arid condition and hence its evaporation is rapid. Desert soil are in saline, the salt concentration in the desert soil is high in lower areas.
The nitrogen level in the desert soil is extremely low which is an important nutrients required by every plant. The desert soil of arid zone are actually sandy to sandy loamy in texture. Desert soil is mainly found in Rajasthan, it covers with the sand at most of the part. Apart from Rajasthan some region of Punjab, Haryana and Gujarat have been found desert soil.
Desert soil is also called ‘bhur’. They develop along with the river courses and coast. South-west monsoon is relatively strong during the summer season in the Rajasthan desert. The contents of desert soil has 90-95% of sand and 5-10% of clay.
6. Mountain soils
Mountain soils are mainly found in hill slopes. This type of soils are formed by deposition of organic matter from wood, forest and other vegetative part. Mountain soils are mostly found in Himalayan region, Sikkim, Uttarakhand, Assam and Arunachal Pradesh.
This type of soil also found in Penisula, Eastern ghat and the Summit of Sahyadris. The properties of Mountain soils depend on the climate and are mainly found in warm temperature belt and cool temperature belt. tthey are rich in humus, fertile and slightly acidic. It is also deprived in lime and Potassium content.
Mountain soil covers about 2.5 square kilometre of the total land of the India. Mountain soil are deficient in Phosphorus, lime and potash. The Plants or crops which are growing in mountain soil needs to deal with fertilizer for the high yield. Tea, coffee spices and tropical fruits are some of the crops which grow well in mountain soil. Other than that wheat, maize and barley are grown in the Himalayan forest areas. Mountain soils are very good for orchard crops.