o Soil Erosion :
Washing away of the fine and fertile top most layer of the soil cover.
o Forms of Soil Erosion
o Sheet
o Rill
o Gully erosion
o Serious constraint on red soil : Sheet erosion
o Sand - dunes are formed by : Wind erosion
o Major consequences of soil erosion :
Desertification and heavy siltation
o Countour bunding : Soil Conservation
o Tribal People : Jhumming or shifting cultivation
o Average erosion of fine soil per hectare in India : 16.4 tonnes
o The older alluvimu soil : Bhangar
o The new / younger alluvium soil : Khadar
o Alluvial Soils :
Formed by river systems through deposition of fine grained sediments.
o Bhangar : More clayey and darker colour
o Khadar : Sandy in texture and light colour.
o Black / Regular / Chernozems soils : Most clayey and moisture retentive capacity.
o Red Soils :
o Derived from weathering of crystalline and metamorphic rocks.
o Absence of lime, kankar, and free carbonates.
o Loamy (fertile) in deep depressions.
o Laterite Soils : Very poor in fertility
o Mountain Soils : Immature soils
o Desert Soils : Formed under arid and semi-arid conditions.
o Cotton : The most suitable crop of black soils or regular soils or chernozems.
Types of Soils :
Alluvial Soils
These soils are formed by river systems through deposition of fine grained sediments rich in lime and potash, deficit in Nitrogen and organic content.
o Bhangar (Older Alluvium)
o Khadar (Newer Alluvium)
Black Cotton (or) Regular Soils
Black soils have developed over Deccan Lavas, Gneisses and Granites under semi-arid conditions.
Tropical chernozems with deep black colour.
Red Soils
Derived from weathering of crystalline and metamorphic rocks. Absence of lime, kankar and free carbonates.
Laterite Soils
It leads to the leaching away of the much of silica from the original rock. These soils are composed of a mixture of hydrated oxides of aluminum and Iron.
Mountain Soils
Include peat, meadow, forest and hill soils.
These are immature soils. Usually deficient in nitrogen, phosphorous and humus
Found in hilly mountainous regions.
Desert Soils
Arid sandy soils as well as wind-blown loess.
Formed as a result of wear and tear and mechanical weathering of rocks in deserts (hot dry climate).
Saline and Alkaline Soils
High proportions of salts and alkalis.
Formed due to accumumation of tidal waters in areas abjoining coasts where drainage is poor.
Marshy Soils
Found in continuously water-logged areas espically in coastal regions.
They are formed as a result of waterlogging.
Contain varying amounts of organic matter.
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