Why this matters now
Soils are a Prelims staple (matching soil type → region → crop) and a GS-3 link to agriculture, soil degradation and conservation. The classification follows the ICAR scheme.
The major soil types
| Soil | Where / crops |
|---|---|
| Alluvial | Most widespread & fertile; the Northern Plains & coastal deltas; rich in potash; rice, wheat, sugarcane. (Older = bhangar; newer = khadar.) |
| Black (Regur) | Deccan Trap (Maharashtra, MP, Gujarat); from volcanic basalt; moisture-retentive, ideal for cotton; rich in lime, iron, magnesia. |
| Red & Yellow | Low-rainfall areas of the Deccan, Eastern Ghats, parts of the NE; reddish from iron oxide; less fertile, need fertiliser. |
| Laterite | High-rainfall, high-temperature areas (Western Ghats, hills); intense leaching; suited to tea, coffee, cashew; used for building bricks. |
| Arid / Desert | Rajasthan & western India; sandy, saline, low humus; cultivable with irrigation. |
| Forest / Mountain | Hill slopes; vary with altitude; good for plantations. |
| Saline & Peaty | Saline/alkaline (Rann, coasts); peaty/marshy (Kerala, deltas, high organic matter). |
Soil degradation and conservation
India faces serious soil degradation — erosion (water and wind), salinity/alkalinity, waterlogging, and loss of fertility from over-cultivation and chemical overuse. Conservation measures include contour ploughing, terracing, shelter belts, crop rotation, afforestation, and schemes like Soil Health Cards to guide balanced fertiliser use.
UPSC angle
Memorise the soil-region-crop matches (alluvial = plains/rice-wheat; black = Deccan/cotton; laterite = high rainfall/tea-coffee). Know the bhangar/khadar split and conservation measures.
Frequently asked questions
Which is the most widespread soil in India?
Alluvial soil, covering the Northern Plains and coastal deltas — the most fertile and agriculturally important.
Which soil is best for cotton?
Black (regur) soil of the Deccan Trap, which is moisture-retentive and rich in lime and iron.
Why is laterite soil found in high-rainfall areas?
Because heavy rain causes intense leaching that removes silica and leaves iron and aluminium oxides; it suits tea, coffee and cashew.
What is the difference between bhangar and khadar?
Bhangar is older alluvium (slightly elevated, with kankar); khadar is newer, more fertile floodplain alluvium renewed each year.