Forests and Soils of India

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Natural Vegetation & Soils in India

Based on climate and rainfall, India's vegetation is divided into several major types:

Rainfall: Found in areas receiving heavy rain > 250 cm.
Distribution: Western slopes of Western Ghats, hills of the northeastern region, and Andaman & Nicobar Islands.
Characteristics: Dense, multi-layered forests. Trees do not shed leaves all at once, hence they appear green year-round. Trees reach heights of 60m or more. Provide valuable hardwood.
Important Flora: Rosewood, Mahogany, Ebony, Rubber, Cinchona.

Most widespread forests in India.
Rainfall: 70 cm – 200 cm.
Trees shed their leaves for about six to eight weeks in dry summer.
Divided into two types based on water availability:
- Moist Deciduous: Rain 100-200 cm. Found in eastern parts of India, foothills of Himalayas, Jharkhand, Odisha, Chhattisgarh, eastern slopes of Western Ghats. Teak is the dominant species. Also Sal, Shisham, Sandalwood.
- Dry Deciduous: Rain 70-100 cm. Found in the rainier parts of the peninsular plateau and plains of UP and Bihar. Large tracts of Teak, Sal, Peepal, Neem. During the dry season, the forest resembles a vast grassland with naked trees.

Rainfall: Less than 70 cm.
Distribution: North-western part of the country including semi-arid areas of Gujarat, Rajasthan, MP, Haryana, UP, and rain shadow area of the Deccan.
Characteristics: Trees are scattered and have long roots penetrating deep to get moisture. Leaves are mostly thick and small to minimize transpiration.
Important Flora: Acacias, Palms, Euphorbias, Cacti, Babool, Khejri.

In mountainous areas, the decrease in temperature with increasing altitude leads to a corresponding change in natural vegetation, mimicking the change from tropical to tundra regions.
1000m - 2000m: Wet temperate type (Oaks, Chestnuts).
1500m - 3000m: Coniferous forests (Pine, Deodar, Silver Fir, Spruce). Found on southern slopes of Himalayas.
Above 3600m: Alpine vegetation (Silver fir, Junipers, Pines, Birches) transitioning into Alpine grasslands/meadows (Bugyals) used for transhumance by tribes like Gujjars and Bakarwals.

Found in the areas of coasts influenced by tides. Mud and silt get accumulated on such coasts.
Dense mangroves having intertwined respiratory roots (pneumatophores) are common.
Distribution: Deltas of the Ganga (Sunderbans), Mahanadi, Krishna, Godavari, and Cauvery.
Important Flora: Sundari tree (provides durable hard timber), Palm, Coconut, Keora, Agar.

The Indian Council of Agricultural Research (ICAR) classifies Indian soils into 8 major categories. The four most important are:

Largest and most important soil group (approx. 43% of total area).
Formation: By deposition of silt by Himalayan rivers (Indus, Ganga, Brahmaputra) and deltaic peninsular rivers.
Distribution: Entire northern plains, coastal deltas.
Characteristics: Extremely fertile. Contains adequate potash, phosphoric acid, and lime. Highly intensively cultivated and densely populated regions.
Types: Khadar (young, highly fertile, fine texture, floodplains) and Bhangar (old, less fertile, contains kankar nodules, terraces).
Crops: Wheat, rice, sugarcane, cotton, jute.

Occupies about 15% of the area.
Formation: Weathering of volcanic basalts of the Deccan Trap.
Distribution: Plateaus of Maharashtra, Saurashtra, Malwa, MP, Chhattisgarh, and along Godavari/Krishna valleys.
Characteristics: Clayey, deep, and impermeable. High moisture retention capacity. When wet, it swells and becomes sticky; when dry, it shrinks and develops deep cracks ("self-ploughing"). Rich in calcium carbonate, magnesium, potash, and lime but poor in phosphoric contents.
Crops: Specially famous for Cotton (hence also called Black Cotton Soil). Also sugarcane, tobacco, wheat.

Develops on old crystalline igneous rocks in areas of low rainfall.
Distribution: Eastern and southern parts of the Deccan Plateau, Odisha, Chhattisgarh, southern parts of middle Ganga plain.
Characteristics: The red colour is due to wide diffusion of iron in crystalline and metamorphic rocks. It looks yellow when it occurs in a hydrated form. Poor in nitrogen, phosphorus, and humus. Can be made fertile with fertilizers.
Crops: Pulses, millets, tobacco, oilseeds.

Derived from the Latin word 'later' meaning brick.
Formation: Develops in areas with high temperature and heavy rainfall. Result of intense leaching due to tropical rains (silica is leached away leaving iron oxide and aluminum behind).
Distribution: Western Ghats peaks, Eastern Ghats, Rajmahal hills, parts of Kerala, Karnataka, Meghalaya.
Characteristics: Very poor in organic matter, nitrogen, phosphate, and calcium. Iron oxide gives it a red color. It hardens like iron when exposed to air, hence widely used as building bricks.
Crops: Not highly fertile, but with heavy manure/fertilizer, useful for Tea, Coffee, Rubber, Cinchona, Cashew nut.

Arid (Desert) Soil: Red to brown color, sandy in texture and saline in nature. Low moisture and humus. Found in western Rajasthan.
Forest and Mountain Soils: Found in the hilly and mountainous areas where sufficient rain forests are available.
Saline & Alkaline Soils: Have excess salts. Found in arid/semi-arid areas or areas with poor drainage (also in canal irrigated areas like Punjab due to over-irrigation causing capillary action of salts to the surface - known as Reh/Kallar).
Peaty and Marshy Soils: Occur in areas of heavy rainfall and high humidity where large quantities of dead organic matter accumulate (Sunderbans, Kerala - Kottayam, Alappuzha).