Soil Types in India.

Alluvial Soil:

• Covers largest area (around 40%) in India.
• Highly Fertile soil.
• Rich in Organic matter and Potash but deficient in Phosphorous.
• Colour – Light grey to Ash grey.
• Areas where Present- Northern Plains and River Valleys, some parts of Gujarat and Rajasthan, Eastern coast deltas.
• It contains calcareous formations known as Kankars.
• Two different types of alluvial soils: Khadar and Bhangar.
• Khadar is the new alluvium which is deposited by the floods annually.
• Bhangar is the old alluvium which is present away from flood plains.

Red and Yellow Soil:

• Covers second largest area (around 18.5%) in India.
• Present in area of low rainfall in eastern and southern Deccan Plateau.
• Areas where Present – Tamil Nadu, Andhra Pradesh, Kerala, Karnataka, Southern Maharashtra, Chhattisgarh, Jharkhand, Odisha and some parts of U.P
• Develops on igneous rocks.
• Soil is Red in colour due to high content of iron in the rocks.
• It appears in Yellow colour when hydrated.
• Poor in nitrogen, humus and phosphorous.

Black Soil:

• Also known as Regur or Black Cotton Soil.
• Parts of Rajasthan, Gujarat, M.P, Maharashtra, Andhra Pradesh and Tamil Nadu. Also present in Godavari and Krishna deltas.
• Rich in Iron, Alumina, magnesia and lime.
• Poor in nitrogen and phosphorous.
• Impermeable nature. It does not absorb water easily.
• It swells when wet and shrinks when dried. So, a kind of Self-Ploughing occurs in this soil.
• Colour- deep Black to Grey.

Laterite Soil:

• Present in the areas with High Rainfall and High Temperature.
• Areas where found – Tamilnadu, Kerela, Karnataka, M.P. Hilly areas of Odisha and Assam.
• Rich in Iron oxide and aluminium compounds.
• Poor in Organic matter.
• Suitable for crops like Cashew nut.
• Leaching of Lima and Silica occurs due to high rainfall.

Arid Soil:

• Characteristic soil of Western Rajasthan.
• Color – Red to Brown.
• Sandy in structure and Saline in nature.
• Kankar layer is present which prevents infiltration of water.
• Found in Dry areas.
• Lack moisture and Humus.

Saline Soils:

• Generally found in Arid, semi-Arid or waterlogged and Swampy areas.
• Contains large proportion of Sodium, Magnesium and potassium. Hence It is infertile.
• Found in western Gujarat, deltas of eastern coast, and in Sunderbans areas of West Bengal.
• Excessive Irrigation also causes Soil to become Saline.
• Gypsum is added to solve the problem of salinity.

Peaty Soils:

• Found in High Rainfall and High Humidity.
• Rich in Organic Matter. 
• About 40 to 50% is the organic matter.
• Peaty soils are heavy in nature and black in color.
• Found in coastal parts of Tamil Nadu, Odisha, West Bengal, Norther parts of Bihar and southern Uttaranchal.

Forest Soils:

• Found in forests and snow-bound areas of Himalayas.
• In lower valleys, it is fertile.
• In Himalayas, they are acidic and have low Organic matter.