GK Question: Important Soils in India
Type of Soils
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Alluvial soil [43%]
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Red soil [18.5%]
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Black / regur soil [15%]
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Arid / desert soil
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Laterite soil
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Saline soil
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Peaty / marshy soil
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Forest soil
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Sub-mountain soil
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Snowfields
Alluvial soil:
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Colour: Light Grey to Ash Grey.
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Highly fertile.
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Humus, lime and organic matters are present.
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In peninsular-India, they are mostly found in deltas and
estuaries.
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Indus-Ganga-Brahmaputhra plain, Narmada-Tapi plain etc
are examples.
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Mostly available soil in India (about 43%) which covers
an area of 143 sq.km.
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New alluvium is termed as Khadar and old
alluvium is termed as Bhangar.
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Poor in: phosphorous.
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Rich in: potash
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Sand content decreases from west to east of the country.
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Texture: Sandy to silty loam or clay.
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They are depositional soil – transported and deposited by
rivers, streams etc.
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Wheat, rice, maize, sugarcane, pulses, oilseed etc are
cultivated mainly.
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Widespread in northern plains and river valleys.
Red soil:
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Absence of lime, kankar (impure calcium carbonate).
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Also known as Omnibus group.
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Colour: Red because of Ferric oxide. The lower layer
is reddish yellow or yellow.
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Deficient in: lime, phosphate, manganese, nitrogen, humus
and potash.
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Porous, friable structure.
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Seen mainly in low rainfall area.
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Texture: Sandy to clay and loamy.
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Wheat, cotton, pulses, tobacco, oilseeds, potato etc are
cultivated.
Black soil / regur
soil:
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Colour: Deep black to light black.
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Deficient in: Nitrogen, Phosphorous and organic
matter.
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High water retaining capacity.
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Mature soil.
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Most of the Deccan is occupied by Black soil.
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Regur means cotton – best soil for cotton
cultivation.
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Rich in: Iron, lime, calcium, potassium, aluminum
and magnesium.
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Self-ploughing is a characteristic of the black soil
as it develops wide cracks when dried.
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Swells and will become sticky when wet and shrink when
dried.
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Texture: Clayey.
Laterite soil:
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Become so soft when wet and so hard when dried.
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Colour: Red colour due to iron oxide.
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Deficient in: Nitrogen, Potash, Potassium, Lime, Humus
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Formed as a result of high leaching.
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In the areas of high temperature and high rainfall.
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Lime and silica will be leached away from the soil.
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Name from Latin word ‘Later’ which means Brick.
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Organic matters of the soil will be removed fast by the
bacteria as it is high temperature and humus will be taken quickly by the trees
and other plants. Thus, humus content is low.
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Rice, Ragi, Sugarcane and Cashew nuts are cultivated
mainly.
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Rich in: Iron and Aluminum
Desert / arid soil:
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Colour: Red to Brown.
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Deposited mainly by wind activities.
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High salt content.
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Kankar or Impure Calcium carbonate content is high which
restricts the infiltration of water.
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Lack of moisture and Humus.
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Nitrogen is insufficient and Phosphate is normal.
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Seen under Arid and Semi-Arid conditions.
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Texture: Sandy
Peaty / marshy soil:
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A large quantity of dead organic matter/humus which makes
the soil alkaline.
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Areas of heavy rainfall and high humidity.
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Growth of vegetation is very less.
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Heavy soil with black colour.
Forest soil:
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Humus content is less and thus the soil is acidic.
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Regions of high rainfall.
Mountain soil:
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In the mountain regions of the country. Immature soil
with low humus and acidic.