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Soil
The loose material or the upper layer of the mantle rock (regolith – a layer of loose, heterogeneous material
covering solid rock) consisting mainly of very small particles and humus which can support the growth of plants
is known as “soil”
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The major factors that influence the formation of soil are parent material, relief,
climate, vegetation, life forms and time
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2
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4
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Soil Profile
The soil profile is a vertical cross-section of the soil, made of layers parallel to the surface
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Horizon A (Topsoil) – It is the topmost layer where the organic materials have got incorporated with the
mineral matter, nutrients and water – elements necessary for the growth of plants
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It represents a transition between Horizon A and Horizon C and contains matter derived from
below as well as above
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This layer is the first stage in the soil formation process and eventually forms the above two
layers
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Different Types of Soil in India
In the ancient period, soils were mainly classified into two – Urvara (fertile) and Usara (sterile)
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In India, the Indian Council of
Agricultural Research (ICAR) has classified soils into 8 categories
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2
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4
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6
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8
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Let’s read about them one by
one:

Types of Soil in India – Alluvial Soil
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Alluvial soils are widespread in the northern plains and river valleys
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These soils are mainly derived from the debris brought down from the Himalayas
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The colour of the alluvial soil varies from light grey to ash grey
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They are rich in potash but poor in phosphorus
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o

Khadar is the new alluvium and occupies the flood plains of the rivers
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Bhangar is the old alluvium, deposited away from the flood plains
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These soils are more loamy and clayey in the lower and middle Ganga plains and the Brahmaputra
valley
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are mainly
cultivated
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It covers about 18
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It is found in regions of low rainfall (eastern and southern parts of the Deccan Plateau)
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This soil is
also present in parts of Odisha and Chattisgarh and in the southern parts of the Middle Ganga Plain
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The soil appears
yellow when it is in hydrated form
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This type of soil is generally deficient in nitrogen, phosphorus and humus
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Types of Soil in India – Black or Regur Soil
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Black soil is also known as “Regur Soil” or the “Black Cotton Soil”
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It covers most of the Deccan Plateau – parts of Maharashtra, Madhya Pradesh, Gujarat, Andhra Pradesh
and some parts of Tamil Nadu
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The colour of these soils varies from deep black to grey
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They swell greatly and become sticky when
wet in the rainy season
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Black soils are rich in iron, lime, aluminium, magnesium and also contain potassium
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Cotton, pulses, millets, castor, tobacco, sugarcane, citrus fruits, linseed, etc
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Types of Soil in India – Desert Soil

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Also known as arid soil, it accounts for over 4
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The colour ranges from red to brown
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These soils are saline in nature and in certain regions the salt content is so high that common salt is
obtained by evaporating water
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Due to increased calcium content in the lower horizons of the soil, there is the formation of ‘kankar’
layers
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Desert soils are profoundly found in western Rajasthan and contain little humus and organic matter
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It accounts for about 3
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These are typical soils of the monsoon climate which is characterised by seasonal rainfall
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Laterite soil is deficient in organic matter, nitrogen, phosphate and calcium, however iron oxide and
potash are in abundance
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Laterite soils are found in Karnataka, Tamil Nadu, Kerala, Madhya Pradesh and hilly regions of Assam
and Odisha
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Laterite soil hardens rapidly and irreversibly on exposure to the air, a property that leads to its use as
building bricks in southern India
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The texture of the soil depends on the mountain environment where they are found
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In the snowbound areas of the Himalayas, these soils undergo denudation and are acidic with low
humus content
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Also called forest soil
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Peaty soils are rich in humus and organic matter
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In many places, these soils are alkaline
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Types of Soil in India – Saline and Alkaline Soils

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These soils have high percentages of sodium, magnesium and potassium, and hence are infertile
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The texture ranges from sandy to loamy
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These soils are deficient in calcium and nitrogen
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In the Rann of Kutch, the south-western monsoon brings salt particles and deposits there
as a crust
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These soils can be reclaimed by improving drainage, by applying gypsum or lime and by cultivating saltresistant crops like berseem, dhaincha, etc
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These are mainly found in Rajasthan,
Haryana, Punjab, Uttar Pradesh, Bihar, and Maharashtra
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It is suitable for leguminous crops
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This soil
performs well if irrigated
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Grey and Brown Soil
These soils are found in Rajasthan and Gujarat
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These loose, friable soils contain iron oxide (haematite and limonite)
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These are
found in the Tarai region of the submontane stretching from Jammu and Kashmir to Assam
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Snowfields
This soil was found under the snow and glaciers at the highest peak of the greater Himalayas, Karakoram,
Ladakh, and Zaskar
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Karewa Soil
Karewa soils are the lacustrine deposits in the Kashmir valleys and Bhadarwah Valley
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They are characterized by fossils
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