Types of Soil in India: Characteristics

1. Alluvial Soil
2. Black Cotton Soil
3. Red & Yellow Soil
4. Laterite Soil
5. Mountainous or Forest Soil
6. Arid or Desert Soil
7. Saline and Alkaline Soil
8. Peaty and Marshy Soil

Types of Soil in India: Characteristics

1. Alluvial Soil

• Widespread Distribution: Alluvial soils are predominant in the northern plains and river valleys of India.
• Coverage: They cover approximately 40% of the total land area of the country.
• Origin: These soils are primarily derived from the debris carried down from the Himalayas by rivers.
• Peninsular Region: In the Peninsular region, alluvial soils are found in the deltas of the east coast and river valleys.
• Color: The color of alluvial soil varies from light grey to ash grey.
• Texture: Alluvial soil exhibits a range of textures, from sandy loam to clay.
• Nutrient Content: Rich in potash but deficient in phosphorus.
• Types: Two main types of alluvial soils exist in the Upper and Middle Ganga plains – Khadar and Bhangar.
• Khadar: Represents new alluvium, found in flood plains, enriched with fresh silt deposits annually.
• Bhangar: Older alluvium located away from flood plains.
• Concretion Presence: Both Khadar and Bhangar soils contain concretions (kankars) of impure calcium carbonate.
• Texture Variation: Alluvial soils are more loamy and clayey in the lower and middle Ganga plains and the Brahmaputra valley.
• Intensive Cultivation: Intensely cultivated for various crops including wheat, maize, sugarcane, pulses, and oilseeds.

2. Black Soil

• Alternative Names: Also known as “Regur Soil” or “Black Cotton Soil.”
• Coverage: Occupies approximately 15% of India’s total land area.
• Distribution: Predominantly found in the Deccan Plateau, covering parts of Maharashtra, Madhya Pradesh, Gujarat, Andhra Pradesh, and some areas of Tamil Nadu. Deep black soil is prevalent in the upper reaches of the Godavari and Krishna rivers, as well as the northwestern part of the Deccan Plateau.
• Color: Ranges from deep black to grey.
• Texture: Typically clayey, deep, and impermeable. Exhibits significant swelling and stickiness when wet during the rainy season, followed by shrinkage and wide cracks during the dry season.
• Composition: Rich in iron, lime, aluminum, magnesium, and potassium. However, deficient in nitrogen, phosphorus, and organic matter.
• Cultivation: Suitable for cultivating crops such as cotton, pulses, millets, castor, tobacco, sugarcane, citrus fruits, and linseed.

3. Red and Yellow Soil

• Alternative Name: Referred to as the “omnibus group.”
• Coverage: Occupies about 18.5% of the total land area of India.
• Distribution: Found in regions with low rainfall, particularly in the eastern and southern parts of the Deccan Plateau. Also present along the piedmont zone of the Western Ghats, parts of Odisha, Chattisgarh, and the southern parts of the Middle Ganga Plain.
• Color: The red color is attributed to the presence of iron in crystalline and metamorphic rocks. In hydrated form, the soil appears yellow.
• Fertility: Fine-grained red and yellow soil is typically fertile, while coarse-grained soil is less fertile.
• Nutrient Content: Generally deficient in nitrogen, phosphorus, and humus.
• Cultivation: Mainly cultivated for crops such as wheat, cotton, oilseeds, millets, tobacco, and pulses.

4. Laterite Soil

• Etymology: The name “laterite” is derived from the Latin word “later,” which means brick, reflecting its brick-like appearance and hardening properties.
• Coverage: Accounts for about 3.7% of India’s total land area.
• Formation: Typical of regions with a monsoon climate characterized by seasonal rainfall. Lime and silica are leached away with rain, leaving behind soil rich in iron oxide and aluminum, leading to the formation of laterite soil.
• Nutrient Content: Laterite soil is deficient in organic matter, nitrogen, phosphate, and calcium. However, it is abundant in iron oxide and potash.
• Fertility: Although low in fertility, laterite soils respond well to manures and fertilizers.
• Geographical Distribution: Found in states such as Karnataka, Tamil Nadu, Kerala, Madhya Pradesh, and hilly regions of Assam and Odisha.
• Suitability for Tree Crops: Red laterite soil in Kerala, Tamil Nadu, and Andhra Pradesh is well-suited for tree crop cultivation, such as cashew nuts.
• Hardening Property: Laterite soil hardens rapidly and irreversibly upon exposure to air. This property makes it valuable for use as building bricks in southern India.

5. Forest Soil (Mountainous Soil)

• Location: Found in forest regions with sufficient rainfall, typically in mountainous environments.
• Texture Variation: The texture of forest soil varies depending on the mountain environment where it is found.
• Upper Slopes: In the upper slopes, forest soils are coarse-grained.
• Valley Sides: On valley sides, forest soils are loamy and silty, providing different conditions for plant growth.
• Himalayan Regions: In the snowbound areas of the Himalayas, these soils undergo denudation and are acidic with low humus content.
• Fertility: Soils found in the lower valleys are fertile, supporting lush vegetation and diverse ecosystems.
• Also Known As: Commonly referred to as forest soil due to its predominant presence in forested areas.

6. Desert Soil

• Alternative Names: Also known as arid soil.
• Coverage: Accounts for over 4.42% of India’s total land area.
• Color: Typically ranges from red to brown.
• Texture: Sandy to gravelly texture, with low moisture content and low water-retaining capacity.
• Salinity: Desert soils are saline in nature, and in certain regions, the salt content is high enough to allow the extraction of common salt by evaporating water.
• Nutrient Content: Normal phosphate content but deficient in nitrogen.
• Kankar Formation: Increased calcium content in the lower horizons leads to the formation of ‘kankar’ layers. These layers restrict water penetration. However, when water is made available through irrigation, soil moisture becomes readily accessible for sustainable plant growth.
• Distribution: Predominantly found in western Rajasthan, characterized by little humus and organic matter.

7. Saline and Alkaline Soil

Characteristics

• High percentages of sodium, magnesium, and potassium, making them infertile.
• High salt content due to dry climate and poor drainage.
• Texture ranges from sandy to loamy.
• Deficient in calcium and nitrogen.

Distribution

• Found in arid and semi-arid areas, waterlogged, and swampy regions.
• Predominantly in western Gujarat, deltas of the eastern coast, Sundarban areas of West Bengal, Rann of Kutch, and near deltas where seawater increases soil salinity.

Reclamation:

• Improve drainage.
• Application of gypsum or lime.
• Cultivation of salt-resistant crops like berseem, dhaincha, etc.

Other Names: Reh, Usar, Kallar, Rakar, Thur, and Chopan.

8. Peaty and Marshy Soils

Characteristics:

• Found in regions with heavy rainfall and high humidity.
• Support good vegetation growth.
• Rich in humus and organic matter.
• Generally heavy and black in color.
• Some areas may have alkaline properties.

Distribution:

• Southern Uttarakhand, northern Bihar, coastal areas of West Bengal, Odisha, and Tamil Nadu.