Soil is made up of crumbled rocks. Three natural forces-wind, flowing water and emperature-weaken the rocks and break them into pieces that are like small stones.These pieces are called the parent material because soil is formed from this material. In India, a wide range of soils is found. On the basis of the natural environmental processes that produce them, these can be broadly divided into two groups, in situ soils and transported soils (formed by the transport of eroded material. The in situ soils get their distinguishing features from the parent rock.
Among the in situ soils of India, the black soil found in the lava-covered land is the most conspicuous. These are often referred to as recur but are popularly known as black cotton soil since cotton has been the prevailing traditional crop on such soils. These are poor in humus yet highly moisture-retentive,responding well to irrigation. Black soils are primarily found in peninsular India where the underlying rock is basalt, as in Maharashtra, Kamataka, Gujarat and Madhya Pradesh.
A much larger area of India has various shades of red in situ soils called lateritic soils. These are generally found over extensive tracts of penisular India that are composed of acidic rocks such as granite, gneiss, and schist. Lateritic soils develop through leaching of soluble minerals, particularly the chemically basic constituents, and enrichment from oxidized iron, which imparts the reddish hue. Heavily reached red soils are found in the high-rainfall areas of the Western Ghats,western Kathiawar peninsula, eastern Rajasthan, the Eastern Ghats, the Chota Nagpur plateau, and other upland tracts of northeastern India. Less-leached red soils occur in areas of low rainfall immediately east of the Western Ghats in the dry interior of the Deccan plateau. Red soils are poor in humus but in forested tracts, humus concentration and the recycling of nutrients help restore fertility in the topsoil. However, humus-rich forest soils are found on all forest-clad mountainous tracts even though the in situ soils of those tracts are not of the same type. Alluvial soils occur widely in India: in all river valleys, deltas and coastal plains. The mineral composition of these transported soils differs according to the source materials. The grain-size distribution also varies according to the distance travelled.
The tracts close to the Himalayas have a coarse-grained alluvium with large annular space, known locally as blabber soil. As these are father sifted and carried some distance,coarse sand particles are gradually replaced by fine sand, with corresponding increase in clay. Hence the permeability of the alluvial soils and correspondingly, their water-holding capacity vary between tracts. In the plains, newer alluvium, locally called Khadar is found on the flood plains This newer alluvium is uniform in texture and extremely fertile. In some of the old alluvium on the slightly elevated terraces,which is termed bhangar, patches of alkaline efflorescence called usar are found. These make the soil infertile. Sandy soil is made up of rocks broken into grains which we call sand.
Sandy soil is grainy It cannot hold water as the water at once seeps down through its grains Such a soil is suitable for crops that need to send their roots easily down and can also stand dry weather. Crops like millets pulses, gram, peanuts and linseed flourish in sandy soil. This type of soil is there in the western Desert of India. If sandy soil gets enough water and manure, it becomes fertile in a short time. Rocky soil is made up of gravel,sand and rock-pieces and is quite coarse to touch. Fruit-trees and maize are two chief crops of this soil. It is found in the hills of Jammu and Kashmir, Himachal Pradesh and Uttar Pradesh.
Among the in situ soils of India, the black soil found in the lava-covered land is the most conspicuous. These are often referred to as recur but are popularly known as black cotton soil since cotton has been the prevailing traditional crop on such soils. These are poor in humus yet highly moisture-retentive,responding well to irrigation. Black soils are primarily found in peninsular India where the underlying rock is basalt, as in Maharashtra, Kamataka, Gujarat and Madhya Pradesh.
A much larger area of India has various shades of red in situ soils called lateritic soils. These are generally found over extensive tracts of penisular India that are composed of acidic rocks such as granite, gneiss, and schist. Lateritic soils develop through leaching of soluble minerals, particularly the chemically basic constituents, and enrichment from oxidized iron, which imparts the reddish hue. Heavily reached red soils are found in the high-rainfall areas of the Western Ghats,western Kathiawar peninsula, eastern Rajasthan, the Eastern Ghats, the Chota Nagpur plateau, and other upland tracts of northeastern India. Less-leached red soils occur in areas of low rainfall immediately east of the Western Ghats in the dry interior of the Deccan plateau. Red soils are poor in humus but in forested tracts, humus concentration and the recycling of nutrients help restore fertility in the topsoil. However, humus-rich forest soils are found on all forest-clad mountainous tracts even though the in situ soils of those tracts are not of the same type. Alluvial soils occur widely in India: in all river valleys, deltas and coastal plains. The mineral composition of these transported soils differs according to the source materials. The grain-size distribution also varies according to the distance travelled.
The tracts close to the Himalayas have a coarse-grained alluvium with large annular space, known locally as blabber soil. As these are father sifted and carried some distance,coarse sand particles are gradually replaced by fine sand, with corresponding increase in clay. Hence the permeability of the alluvial soils and correspondingly, their water-holding capacity vary between tracts. In the plains, newer alluvium, locally called Khadar is found on the flood plains This newer alluvium is uniform in texture and extremely fertile. In some of the old alluvium on the slightly elevated terraces,which is termed bhangar, patches of alkaline efflorescence called usar are found. These make the soil infertile. Sandy soil is made up of rocks broken into grains which we call sand.
Sandy soil is grainy It cannot hold water as the water at once seeps down through its grains Such a soil is suitable for crops that need to send their roots easily down and can also stand dry weather. Crops like millets pulses, gram, peanuts and linseed flourish in sandy soil. This type of soil is there in the western Desert of India. If sandy soil gets enough water and manure, it becomes fertile in a short time. Rocky soil is made up of gravel,sand and rock-pieces and is quite coarse to touch. Fruit-trees and maize are two chief crops of this soil. It is found in the hills of Jammu and Kashmir, Himachal Pradesh and Uttar Pradesh.
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