Soil Types in India: Traits and Impact on Agriculture

India, with its vast and varied landscape, is home to a rich tapestry of soils, each with distinct characteristics and distribution patterns. The country boasts an array of soil types in India, ranging from the fertile black soils to the arid expanses, saline terrains, and the unique laterite and peaty soils. 

In this article, we delve into the key soil types in India found across India, unraveling their individual traits and understanding how they contribute to the nation’s agricultural and environmental dynamics.

Soil Types in India – Red & Yellow Soil

Area: Red and Yellow Soils

• These are predominantly found on crystalline igneous rocks in the eastern and southern regions of the Deccan Plateau under low rainfall conditions and extend along the piedmont zone of the Western Ghat, showcasing a stretch of red loamy soil. 
• These soils are also present in parts of Odisha, Chattisgarh, and southern areas of the Middle Ganga Plain. 

Arid Soil

Characteristics: Red and Yellow Soils

• They exhibit a reddish hue due to iron diffusion in crystalline and metamorphic rocks, turning yellow when hydrated. 
• While the fine-grained red and yellow soils are typically fertile, the coarse-grained variants in dry upland areas lack fertility. 

Mineral Composition: Red and Yellow Soils

• These soils are generally deficient in nitrogen, phosphorous, and humus, delineating a crucial understanding of their utilisation and management.

Soil Types in India – Laterite Soil

• Derived from the Latin word ‘Later’ meaning brick, laterite soils form in high temperature and high rainfall areas, undergoing intense leaching due to tropical rains.
• Rain washes away lime and silica, leaving behind soils rich in iron oxide and aluminium compounds. 

Mineral Composition: Laterite Soils

• Because they lack organic matter, nitrogen, phosphate, and calcium but are abundant in iron oxide and potash.
• These soils are initially unsuitable for cultivation, requiring manures and fertilisers to enhance fertility.
• Humus content of the soil is removed fast by bacteria that thrives well in high temperatures.

Area: Laterite Soils 

• Being widely used as bricks for construction, laterite soils predominantly occupy higher areas of the Peninsular plateau.
• It is notably found in Karnataka, Kerala, Tamil Nadu, Madhya Pradesh, and the hilly regions of Odisha and Assam. 

Characteristics: Laterite Soils

• Red laterite soils are favourable for tree crops like cashew nuts.It is found in regions of Tamil Nadu, Andhra Pradesh, and Kerala, 
• This distribution and character of laterite soils are crucial for understanding their agricultural and constructional utility in these regions.

Soil Types in India – Arid Soil

Area: Arid Soils

These soils are chiefly found in western Rajasthan, showcasing the region’s arid topography.

Characteristics: Arid Soils

• They are characterised by a colour range from red to brown, predominantly having a sandy structure and a saline nature.
• Salt content is so high in certain areas that common salt can be extracted through evaporation. 
• Their fertility is hindered by the low humus and organic matter content, highlighting a need for substantial soil management for productive agricultural usage.

Mineral Composition: Arid Soils

• A notable feature is the ‘kankar’ layers in the lower horizons due to increasing calcium content. 
• The kankar layer restricts water infiltration but ensures soil moisture retention when irrigation is introduced, aiding sustainable plant growth. 
• Due to the arid climate, high temperatures, and rapid evaporation, these soils lack moisture and humus, with nitrogen being insufficient, though phosphate content remains normal. 

Soil Types in India – Saline Soils

Area: Saline Soils 

• Predominantly found in arid, semi-arid, waterlogged, and swampy regions due to the dry climate and poor drainage, their structure varies from sandy to loamy. 
• Major occurrences are noted in western Gujarat, the eastern coast deltas, and the northern Sundarban areas of West Bengal. 
• The Rann of Kachchh sees salt depositing crusts brought by the Southwest Monsoon, while seawater intrusion in deltas further contributes to soil salinity.

Characteristics: Saline Soils

• Also known as Usara soils, saline soils are marked by a high proportion of sodium, potassium, and magnesium, rendering them infertile and unsupportive of vegetative growth. 
• Intensive cultivation zones, especially Green Revolution areas with excessive irrigation, witness fertile alluvial soils turning saline. 
• The capillary action, encouraged by excessive irrigation in dry climates, deposits salt on the soil’s top layer. 
• This scenario, particularly seen in Punjab and Haryana, prompts advice for farmers to add gypsum as a remedial measure against soil salinity, emphasising a balance between irrigation practices and soil management to maintain soil fertility and agricultural productivity.

Mineral Composition: Saline Soils 

• Saline soils are deficient in nitrogen and calcium. 
• High proportion of sodium, potassium, and magnesium is found in these soils

Soil Types in India – Peaty Soils

Area: Peaty Soils  

• Geographically, peaty soils are widely distributed in northern Bihar and southern Uttaranchal, along with coastal stretches of West Bengal, Orissa, and Tamil Nadu.  

Characteristic: Peaty Soils 

• These soils are typically heavy, black in colour, and, in many locales, exhibit alkaline properties.  
• Peaty soils are prominently found in regions with heavy rainfall and high humidity.
• These soils are conducive to lush vegetation growth that, upon decomposition, contributes to the soil’s rich humus and organic content, often reaching 40-50%. 
• The substantial organic matter within these soils reflects the region’s dense vegetative cover, which in turn is significantly influenced by the local climatic conditions.

Mineral Composition: Peaty Soils

• Peaty soils have a low proportion of minerals compared to organic matter.
• With the exact mineral content varying depending on the specific location and conditions in which the soil has formed.

Soil Types in India – Forest Soils

Area: Forest Soils

• Forest soils, inherent to regions with ample rainfall, exhibit varied structure and texture based on the specific mountainous environment such as in Arunachal Pradesh, and Himachal Pradesh.

Characteristics: Forest Soils 

• They are categorised as loamy and silty on valley sides and coarse-grained on upper slopes. 
• Particularly in the snow-clad regions of the Himalayas, these soils undergo denudation, becoming acidic with a low humus content. 

• However, the soils in the lower valleys are notably fertile. 
• The discourse emphasises the intrinsic link between the texture, quality, and nature of soils and the germination and growth of plants and vegetation, including crops. 

DOWNLOAD PDF