Indian Soil Types

• Study notes on Indian Soil Types

Alluvial Soil

• Alluvial soil covers approximately 40% of India's total land area.
• It is found in Northern plains, river valleys, parts of Rajasthan, Gujarat, peninsular India, and east coast deltas.
• This soil is a depositional soil formed by rivers.
• The texture ranges from sandy to loamy to clayey.
• It is rich in potash, but poor in phosphorus.
• Khadar is the new alluvium and is more fertile, while Bhangar is the older alluvium that contains calcareous nodules called kankars.

Black Soil (Regur/Black Cotton Soil)

• Black soil is located in the Deccan Plateau, including Maharashtra, MP, Gujarat, Andhra Pradesh, and parts of Tamil Nadu.
• It is clayey, deep, and impermeable.
• This soil develops wide cracks in the dry season, making it self-aerating.
• It retains moisture well.
• It is rich in lime, iron, magnesia, alumina, and potash.
• Black soil is deficient in phosphorus, nitrogen, and organic matter.

Red and Yellow Soils

• These soils form from crystalline igneous rocks in areas with low rainfall.
• They are found in the eastern and southern Deccan Plateau, Odisha, Chhattisgarh, and southern Middle Ganga plains.
• The red color is due to iron diffusion.
• It appears yellow when iron is hydrated.
• Red and yellow soils are poor in nitrogen, phosphorus, and humus.

Laterite Soil

• The term 'Laterite' means brick.
• This soil forms due to intense leaching in high temperature and high rainfall areas.
• It is located in Tamil Nadu, Andhra Pradesh, Kerala, Karnataka, MP, hilly Odisha, and Assam.
• It is rich in iron oxide and potash.
• Laterite soil is poor in organic matter, nitrogen, phosphate, and calcium.
• It is unsuitable for normal farming but suitable for tree crops like cashew.
• This soil is used as bricks in construction.

Arid Soil

• Arid soil is red to brown in color.
• Its texture is sandy and saline.
• It is predominantly found in western Rajasthan.
• This soil lacks moisture and humus.
• It is poor in nitrogen but normal in phosphate.
• Lower layers have kankar, which restricts water infiltration.

Saline Soil (Usara Soil)

• This soil has a high content of sodium, potassium, and magnesium.
• It is found in arid/semi-arid areas, waterlogged and swampy regions, western Gujarat, east coast deltas, and the Sundarbans, West Bengal.
• It is infertile and deficient in nitrogen and calcium.
• Fertile alluvial soils can become saline due to overuse.
• Gypsum is added to reduce salinity.

Peaty Soil (Peat Soil)

• Peaty soil forms in areas with high rainfall and humidity, leading to the accumulation of dead organic matter.
• Organic matter content is up to 40–50%; it is very rich in humus.
• It is heavy, black, and alkaline.
• This soil is located in Northern Bihar, Southern Uttarakhand, coastal West Bengal, and Odisha, Tamil Nadu.

Forest Soil

• Forest soil forms in areas with adequate rainfall.
• It is located in snow-bound Himalayan regions.
• It is generally acidic.
• Lower valleys containing this soil are fertile.