Green India: Forests, Mangroves and the Wildlife They Shelter

India holds everything from dripping evergreen rainforest to cactus-dotted thorn scrub to cold desert moss, within one country's borders. The secret is a rainfall map that swings from 11,000 mm to nearly zero, and a mountain wall that stacks climates vertically.

Why India's vegetation is so varied

Four factors write the vegetation map. Rainfall is the master control, the same monsoon that floods Meghalaya starves the Thar, and the forest changes with the isohyet. Temperature falls with altitude, so the Himalaya stacks tropical, subtropical, temperate and alpine belts on one slope. Soil decides the specialists, mangroves and swamp forests exist where soil, not climate, is the boss. And topography carves the exceptions, from tidal forests at sea level to alpine flora at 4,000 metres.

This variety is why the 2023 mains paper could ask what creates India's natural-vegetation diversity: vast latitudinal spread, the Himalayan altitudinal staircase, the monsoon's violent rainfall gradient, and soils that range from alluvial silt to saline desert, all inside one subcontinent.

The forest types, coast to peak

Tropical evergreen

• Rainfall above 200 cm, temperatures 22-27°C; trees tower to 60 m in layered canopies with almost no undergrowth, and stay green year-round with no fixed leaf-shedding season.
• Western Ghats (Maharashtra, Karnataka, Tamil Nadu, Kerala), the Andaman and Nicobar Islands and the entire northeast.
• Mahogany, rosewood, ebony, jamun, white cedar, canes and bamboo; the wood is hard and heavy.

Tropical semi-evergreen

• Transitional belts with 200-250 cm rain and a longer dry season; a mix of evergreen and moist deciduous trees with broken canopies and abundant climbers and epiphytes.
• Western Ghats, Assam, West Bengal, Odisha, the Shiwalik strip and the Chota Nagpur plateau; more extensive than pure evergreen.

Tropical moist deciduous (monsoon forests)

• The most common Indian forest: 100-200 cm of rain, trees shed leaves for six to eight weeks in the dry spring and summer and stand bare.
• Northeastern states, Himalayan foothills, eastern slopes of the Western Ghats, Madhya Pradesh, Chhattisgarh, Chota Nagpur and the Eastern Ghats.
• Sal, teak, sandalwood, shisham, mahua, kusum and bamboo, the great timber and revenue forests of India.

Tropical dry deciduous

• Grows on 70-100 cm of rain, transitional between moist deciduous and thorn forest; in the rainier peninsula it opens into a parkland of teak and grass.
• Rainier parts of the peninsula and the plains of UP and Bihar; large tracts cleared for farming and grazing.
• Teak, tendu, palas, bel, neem, red sanders and axlewood.

Tropical thorn

• Under 70 cm of rain and humidity below 50 percent: low scattered trees 6-10 m tall, leafless most of the year, with deep roots, tiny thick leaves and water-storing stems.
• Northwestern India, Rajasthan, southwestern Punjab, western Haryana, Kutch, and the leeward side of the Western Ghats.
• Babool, ber, wild date palm, khair, neem, khejri, acacias and cacti.

Tropical dry evergreen

• A Tamil Nadu coast speciality: about 100 cm of rain mostly from the northeast monsoon, short 12-metre trees with leathery leaves and a complete canopy.
• Khirni, jamun, kokko, ritha, tamarind, neem and toddy palm along the Coromandel coast.

Littoral and tidal (mangrove) forests

• Wetland forests that thrive in coastal, waterlogged, saline conditions, in both fresh and brackish water, and anchor the shoreline against storms.
• The deltas of the Ganga, Mahanadi, Godavari, Krishna and Cauvery, plus the Andaman and Nicobar Islands.
• Sundari trees, Rhizophora, Avicennia and Heritiera; the Sundarbans of West Bengal is the world's largest delta and mangrove forest.

Montane forests, Himalaya and the southern hills

• Subtropical pine (1,000-1,800 m): chir pine dominant, with jamun and oak, resin, turpentine and railway timber country.
• Temperate (1,500-3,300 m): deodar, blue pine, oak, birch and chestnut; the wet-temperate Shola forests of the Nilgiri and Palni hills are their southern cousins.
• Alpine (3,000-4,000 m): silver fir, juniper and rhododendron giving way to mosses and lichens; dry alpine scrub above 3,500 m.

Compressed into one table, the rainfall rule that runs this whole chapter:

Mangroves: the forests that stand in the sea

Mangroves are the coastline's shock absorbers, dense tidal forests that blunt storm surges, shelter fish nurseries and lock away blue carbon. The 2019 mains paper asked why they are vanishing: reclamation for ports and aquaculture, pollution, fuelwood cutting, and saltwater intrusion from sea-level rise, one study linked the 2017-2020 record sea levels to mangrove dieback around the Indian Ocean.

The numbers tell a recovery story with a warning. One passage in the sources gives an older figure of 6,740 sq km, but the India State of Forest Report 2023, the authoritative count, puts India's mangrove cover at 4,991.68 sq km, just 0.15 percent of the country's area, with a net gain of 363.68 sq km since 2021. West Bengal leads, followed by Gujarat and the Andaman and Nicobar Islands.

Yet the same report records a disappearance of 3,913 sq km of dense forest since 2021, a reminder that total cover can rise through plantations and open forest while the richest, oldest forests keep shrinking.

Policy has noticed the mangrove's value. MISHTI, the Mangrove Initiative for Shoreline Habitats and Tangible Incomes announced in the 2023-24 Union Budget, funds mangrove plantation on salt pans and degraded coasts, treating the mangrove belt as living infrastructure that guards the shore, nurses fisheries and can earn carbon income while it grows. It applies the Green India Mission's logic at the water's edge: cover that pays for itself stands a better chance of surviving.

How much forest India actually has

Forest cover means land over one hectare with tree canopy density above 10 percent, it includes orchards, bamboo and palm, not just recorded forests. ISFR 2023 counts total forest and tree cover at 25.17 percent of India's geographical area, with forest cover alone at 21.76 percent. Since 2021 the combined cover grew by 1,445 sq km, with forest cover itself up 156 sq km; the biggest gainers were Mizoram, Gujarat and Odisha.

The league tables: Madhya Pradesh has the largest forest cover by area, while Lakshadweep has the highest share at 91.33 percent of its area, followed by Mizoram and the Andaman and Nicobar Islands. Nineteen states and UTs cross the 33-percent mark and eight cross 75 percent. India's forest carbon stock is estimated at 7,285.5 million tonnes, up 81.5 million tonnes since 2021, a quiet climate asset.

The Forest Survey of India grades canopy density into very dense (70 percent or more), moderately dense and open forest. Tribal districts, 188 of them, hold about 59.6 percent of the country's forest cover on just a third of its area, tying forest conservation directly to tribal India.

The conservation framework

India's first forest policy came in 1952 and was rewritten in 1988 with a famous target: bring 33 percent of the land under forest or tree cover, maintain environmental stability, restore degraded forests, conserve biological diversity, check soil erosion and hold back the desert. Social forestry, urban, rural and farm forestry, and agroforestry (trees plus crops on the same land) were the delivery tools.

The protected-area network rests on biosphere reserves: India has 18, and 13 of them now sit in UNESCO's Man and the Biosphere network, the Cold Desert of Lahaul-Spiti in Himachal Pradesh became the 13th in 2025. Below them, national parks and wildlife sanctuaries guard the richest habitats, including the rainforest tracts the 2023 mains paper asked about, islands of evergreen forest in the Western Ghats and the northeast where endemic species survive nowhere else.

Project Tiger (1973) created dedicated, centrally assisted tiger reserves after tiger numbers crashed; Project Elephant (1992) extended the same model to elephant habitats and corridors, and the launch year is a favourite match question.

The scale underneath keeps the exam busy: over a hundred national parks, where protection is strictest and grazing and private rights are barred, and more than five hundred wildlife sanctuaries, where limited regulated activity is allowed. Repair money flows through CAMPA, which routes funds collected for forest land diverted to other uses back into afforestation, while the Green India Mission works on better cover and ecosystem services.

The 2020 mains question linked forest status to climate change, and the logic runs both ways: forests are a carbon sink and a monsoon anchor, while warming, fires, Uttarakhand, Odisha and Chhattisgarh reported the most fire incidents in 2023-24, and fragmentation eat into exactly that asset.

Coral reefs: India's underwater forests

Coral reefs are ridge-like structures built over millennia by colonies of coral polyps secreting calcium carbonate. They need warm (roughly 20 to 30 degrees Celsius), shallow, clear, sunlit and low-nutrient water, which is why they fringe the tropics. Reefs come in three classic forms: fringing reefs hugging the shore, barrier reefs separated from land by a lagoon, and atolls (ring-shaped reefs around a submerged island, Darwin's famous subsidence theory).

India's reef geography is compact and testable: the Gulf of Mannar (Tamil Nadu) and the Gulf of Kachchh (Gujarat) hold fringing and platform reefs, Lakshadweep is a chain of true coral atolls, and the Andaman and Nicobar Islands have some of India's richest fringing reefs. UPSC's 2019 mains asked for an assessment of global warming's impact on coral life systems: the answer runs through bleaching (see geo-07), sea-level change and acidification, with these four Indian addresses as the examples.

Key Terms

• NTCA, the National Tiger Conservation Authority: The NTCA is the National Tiger Conservation Authority, a statutory body under the Ministry of Environment, Forest and Climate Change created by the 2006 amendment to the Wildlife (Protection) Act, 1972. It oversees Project Tiger, approves tiger reserve management plans, and monitors the tiger census. It matters for UPSC because tiger conservation, protected-area governance, and human-wildlife conflict are standard GS-III environment topics. Oversees Project Tiger, launched in 1973.
• Wildlife Protection Act of 1972: Wildlife Protection Act of 1972 is India's umbrella legislation for protecting wild animals, birds and plants, creating schedules of protected species and categories of protected areas like national parks and sanctuaries. It set up authorities such as the National Tiger Conservation Authority and the Central Zoo Authority, and enabled Project Tiger in 1973. It matters for UPSC as the legal backbone of conservation, tested on schedules, amendments and protected-area categories. Project Tiger, launched in 1973 under its framework
• Andaman and Nicobar Islands: The Andaman and Nicobar Islands are a Union Territory of 572 islands in the Bay of Bengal, stretching toward the Malacca Strait. They carry the Cellular Jail of the freedom struggle, India's only active volcano at Barren Island, and the country's first tri-service theatre command. Their capital, Port Blair, was renamed Sri Vijaya Puram on 13 September 2024. For UPSC, they anchor questions on island security, tsunami vulnerability, and Act East strategy. The Andaman and Nicobar Command, raised in 2001, is India's only operational tri-service command.
• Joint Forest Management: Joint Forest Management is India's participatory forest governance model, formalised by a Government of India resolution in June 1990. Under it, village-level Joint Forest Management Committees protect and regenerate forests in partnership with the Forest Department, receiving usufruct rights such as fuelwood and fodder in return. It matters for UPSC because it is the flagship example of community-based natural resource management in environment and governance answers. The Arabari experiment in West Bengal in the early 1970s, led by forester A.K. Banerjee, was the pioneering model for JFM.
• Green India Mission: The Green India Mission is one of the eight missions under the National Action Plan on Climate Change, launched to expand and improve India's forest and tree cover. It combines afforestation and reforestation with livelihood support for forest-dependent communities, aiming at ecosystem restoration and carbon sequestration together. For UPSC, it is a standard GS-3 environment answer point on India's climate policy, linking forests, adaptation and community participation. Its launch in 2014 as part of the NAPCC, alongside the Solar Mission and the Water Mission.
• Gulf of Kachchh: The Gulf of Kachchh is a shallow inlet of the Arabian Sea indenting Gujarat's coast between the Kachchh and Saurashtra peninsulas. Known for extensive tidal flats, salt pans and coral and mangrove ecosystems, it hosts ports, refineries and India's first marine national park on its southern shore. For UPSC, it features in GS-1 geography and GS-3 environment answers on coastal ecosystems, tidal energy potential and industrial pressure on marine habitats. The Marine National Park in the Gulf of Kachchh near Jamnagar, India's first marine national park.
• Gulf of Mannar: The Gulf of Mannar is the shallow bay between southeastern Tamil Nadu and northwestern Sri Lanka, connected to Palk Bay by the Adam's Bridge (Rama Setu) chain of shoals. It hosts coral reefs, seagrass beds, pearl banks and dugongs, protected as India's first marine biosphere reserve (1989). It matters for UPSC because it links geography (Palk Strait, Sethusamudram project), biodiversity and the sensitive India-Sri Lanka maritime boundary, including the Katchatheevu issue. The Gulf of Mannar Biosphere Reserve, India's first marine biosphere reserve, covering over 10,500 square kilometres of reefs and islands.
• biodiversity hotspots: Biodiversity hotspots are biogeographic regions with exceptional species richness and high endemism that have lost at least 70 percent of their original habitat, a concept introduced by Norman Myers. Conservation International recognises 36 hotspots globally, four of them partly or wholly in India. For UPSC environment prelims, hotspots are a high-frequency topic linked to endemic species, protected areas, and conservation strategy. The Western Ghats, a biodiversity hotspot shared with Sri Lanka
• biosphere reserve: A biosphere reserve is a large protected landscape zoned into a strictly protected core, a buffer for research and education, and a transition zone where people live and work sustainably. India has 18, beginning with the Nilgiri in 1986, and 13 of them sit in UNESCO's World Network of Biosphere Reserves. The model matters because it conserves ecosystems with their human communities inside the frame, not evicted from it.
• Ramsar Convention: The Ramsar Convention is the 1971 international treaty, adopted at Ramsar in Iran, that provides a global framework for the conservation and wise use of wetlands, especially as waterfowl habitat. Parties designate wetlands of international importance as Ramsar Sites and commit to maintaining their ecological character. India has over 85 Ramsar Sites. For UPSC prelims it is the classic environment treaty alongside CITES and the Bonn Convention. Chilika Lake in Odisha, designated a Ramsar Site
• Project Elephant: Project Elephant, launched in 1992, is a centrally sponsored scheme of the Ministry of Environment, Forest and Climate Change for protecting elephants, their habitats, and migratory corridors, and for mitigating human-elephant conflict. It supports a network of Elephant Reserves across elephant-range states and funds anti-poaching and habitat work. It is a prelims environment staple, asked alongside Project Tiger of 1973. Gaj Yatra, the nationwide awareness campaign launched in 2017
• Chipko movement: The Chipko movement is the 1973 forest-conservation movement of Uttarakhand's hill villages, where villagers led by Sunderlal Bahuguna and Chandi Prasad Bhatt hugged trees to stop commercial felling. It grew from the Dasholi Gram Swarajya Mandal's campaign against forest contractors and fused Gandhian non-violence with livelihood ecology. For UPSC, it is the canonical people's environmental movement in GS-3 and the precursor to the 1980 moratorium on green felling in the Himalayan region. Gaura Devi leading the women of Reni village to protect their forest from loggers in 1974.

Practice questions