Classification of Indian Forests

India boasts a diverse array of forests, with its total forest and tree cover now encompassing 24.56% of the country's overall geographical area. Among the most significant types of forests in India are coniferous forests, evergreen forests, wet evergreen forests, deciduous forests, broadleaved forests, and mangrove forests.

FOREST

• The responsibility of defining what qualifies as a forest lies with individual states. 
• The Supreme Court's ruling in the T.N. Godavarman Thirumulkpad vs the Union of India case in 1996 affirmed the states' authority to establish the criteria for identifying forests.
• In this landmark decision, the Supreme Court emphasized that the term "forest" should be interpreted based on its dictionary definition. 
• This interpretation is applicable to all legally acknowledged forests, irrespective of their categorization as reserved, protected, or any other classification.

Sir HG Champion made a pioneering effort in the classification of India's forest types with his monumental work, 'Preliminary Survey of Forest Type of India and Burma,' published in 1936.

Subsequently, in 1968, Champion, along with Seth, presented an updated classification in 'A Revised Survey of the Forest Kinds of India.'

The classification methodology takes into account various factors, including climate, physiognomy (general appearance of vegetation), species composition, phenology (seasonal changes), terrain, soil characteristics, altitude, aspect, and biotic factors. This comprehensive approach provides a detailed understanding of the diverse forest ecosystems in India.

India's forests are broadly categorized into six "major groupings" that span from tropical to alpine regions. 

Within these major groupings, further subdivisions are made into 16 sub-groups based on specific temperature and moisture regimes. 

This hierarchical classification system enables a nuanced and precise categorization of the rich and varied forest landscapes across the country.

Tropical Wet Evergreen Forests

• Located in the southern states of Maharashtra, Karnataka, Tamil Nadu, Kerala, and the Andaman and Nicobar Islands, as well as the entire northeastern region, including West Bengal's sub-mountain division.
• Tropical Wet Evergreen Forests boast an annual rainfall exceeding 250 cm. 
• With an average annual temperature ranging between 25 and 27 degrees Celsius, and humidity around 77 percent, these forests experience a brief dry season. 
• Characterized by minimal undergrowth and infrequent litter, they host valuable species such as mahogany, mesua, white cedar, jamun, canes, and bamboo.

Tropical Semi-Evergreen Forests

• Functioning as a transitional zone between tropical wet evergreen and tropical deciduous forests, Tropical Semi-Evergreen Forests inhabit the Western coast, Assam, lower slopes of the Eastern Himalayas, Odisha, and Andaman Island. 
• With an annual rainfall of 200-250 cm and an average temperature of 24-27 degrees Celsius, these forests feature teak, jamun, cashew, hog plum, coral tree, jasmine, and crossandra. 
• Diverse wildlife, including Indian Leopard, Indian giant Squirrel, Lemur, Deer, One-Horned Rhinos, Birds, Great Horn Bill, Bats, Sloth, Scorpions, and Snails, thrives in this environment.

Tropical Moist Deciduous Forests

• Widespread across India, except in the western and northwestern regions, Tropical Moist Deciduous Forests endure rainfall between 100 and 200 cm. 
• These economically significant forests house species like Sal, Adina Cardifolia (Kusum), Xylia Xylocarpa, Anogeissus Iatifolia (Dhau), and Machilus Villosa.
• Notably, the endangered Hoolok Gibbon finds its habitat in the tropical moist deciduous forests of Manipur.

Littoral and Swamp

• Abundant across India, Littoral and Swamp Forests are prevalent in Deccan Plateau reservoirs, Gujarat's saline coast, Rajasthan's saline coast, the Gulf of Kutch, Eastern Coast Deltas, Kashmir's lakes and rivers, and North East India's swamps. 
• These evergreen swamp forests, thriving in waterlogged areas, support a productive mangrove ecosystem, offering shelter and a nursery for various fish species and other animals.

Tropical Dry Deciduous Forest

• Found predominantly in North India and the Deccan Plateau's southern parts, Tropical Dry Deciduous Forests extend into the plains of Bihar, Uttar Pradesh, and the northeastern regions of the Peninsular plateau. 
• These forests, rich in biodiversity, host species like Teak, Coromandel Ebony, Dhaora, Lagerstroemia Parviflora, Terminalia Tomentosa, Lannea Coromandelica, and Boswellia Serrata. 
• Notable inhabitants include the Bengal Tiger, Gaur, Dhole, Sloth Bear, Chousingha, and Blackbuck.

Tropical Thorn Forests

• Primarily located in northern India and some drier areas of the Deccan Plateau, Tropical Thorn Forests endure an annual rainfall of less than 70 cm. 
• Dominated by stunted Acacia species, including Prosopis, Grewia, Salvadora, Zizyphus, Anogeissus, Gardenia, Capparis, and Carissa, these forests are home to diverse carnivores like the common leopard, caracal, Indian desert cat, jungle cat, rusty-spotted cat, grey wolf, golden jackal, desert fox, Indian fox, and striped hyena.

Tropical Dry Evergreen Forest

• Exclusive to Tamil Nadu and Andhra Pradesh, Tropical Dry Evergreen Forests are limited to a coastal strip from Vishakapattinam in Andhra Pradesh to Ramanathapuram in Tamil Nadu. 
• With varying rainfall distribution, these forests feature fine-pored soils, high clay content.
• An array of species such as Ceylon Wood, Spanish Cherry, Ceylon Ebony, Nux-vomica, Eugenia, Veerai Tree, and Indian Plum. Inhabitants include the Dhole, Sloth Bear, and Indian Spotted Chevrotain.

Subtropical Broad-Leaved Forests

• Stretching from central Nepal's middle hills through Darjeeling, Bhutan, and into Uttar Pradesh and Bihar in India.
• Subtropical Broad-Leaved Forests form a tall forest at 500 to 1,000 m. Sal, Terminalia, Bauhinia, Schima, and Castanopsis species dominate these forests.
• Housing threatened mammals like the Bengal Tiger, Indian Elephant, Smooth-coated Otter, Clouded Leopard, Gaur, Sumatran Serow, Irrawaddy Squirrel, and Particolored Flying Squirrel.

Subtropical Pine Forests

• Covering a significant elevation range of 800 to 2000 meters in northeast India's hilly states, Subtropical Pine Forests rely on the southwestern monsoon for rainfall. 
• Trees such as Shisham, Teak, Sal, Pine, Fir, Juniper, and Rhododendron populate these forests, which lack stable populations of large carnivores due to scarce wild prey.

Subtropical Dry Evergreen Forest

• Found in the western Himalayas, Bhabar, and Shiwaliks up to 1000 meters above sea level, Subtropical Dry Evergreen Forests endure an annual rainfall of 800 millimeters. 
• The ecoregion supports globally threatened species like the Lesser Florican and features diverse bird life, including the Woolly-necked Stork, White-bellied Sea-eagle, and Indian Gray Hornbill.

Montane Wet Temperate Forests

• Occurring on moderate-height mountains, Montane Wet Temperate Forests are distributed in the southern parts of India, including Kerala and Tamil Nadu's upper mountainous areas. 
• Trees like Cullenia Exarillata, Mesua Ferrea, Palaquium Ellipticum, Gluta Travancorica, and Nageia Wallichiana characterize these forests. 
• Endemic species like the Nilgiri Tahr, Nilgiri Pipit, Nilgiri Laughingthrush, Broad-tailed Grassbird, and Nilgiri Long-tailed Tree Mouse inhabit this ecoregion.

Himalayan Moist Temperate Forest

• Extending the entire length of the Himalayan mountain range, Himalayan Moist Temperate Forests grow between 1500 and 3300 meters above sea level. 
• These forests receive 150 to 250 cm of annual rainfall, with diverse species like pines, cedars, silver firs, spruce.
• Royal Bengal Tiger, Barking Deer, and Himalayan Black Bear. 
• Vulnerable species like the Himalayan Black Bear find refuge in this habitat.

Himalayan Dry Temperate Forest

• Occupying middle altitudes in the Himalayas, Himalayan Dry Temperate Forests feature an open evergreen forest with an undergrowth of open scrub. 
• Experiencing mild summers and lengthy, cold winters, these forests host temperate zone conifers like deodar, blue pine, fir, and spruce. 
• Endangered wildlife such as the Snow Leopard, Tibetan Wolf, Tibetan Argali, and Black-necked Crane inhabit this ecoregion.

Subalpine Forest

• Functioning as a transition zone between dense forest and alpine tundra, Subalpine Forests are conifer-dominated forests found primarily in temperate latitudes' subalpine zone. 
• These forests, characterized by trees like Abies Spectabilis, Larix Griffithii, Betula Utilis, Acer, and Sorbus, host diverse animal species including the Brown Bear, Himalayan Serow, Markhor Goat, White-bellied Musk Deer, and Red Panda.

Moist Alpine Scrub

• Spanning from 3000 meters up to the snowline, Moist Alpine Scrub occurs in both the main Himalayan regions and the trans-Himalayan barren freezing deserts. 
• With a subarctic to arctic climate and heavy snowfall, this scrub supports stunted trees like black juniper and drooping juniper. 
• Notable mammals include Snow Leopards, Himalayan Blue Sheep, Himalayan Tahr, Takin, Himalayan Musk Deer, Himalayan Goral, and Himalayan Serow.

Dry Alpine Scrub

• Thriving over 3500 meters above sea level, Dry Alpine Scrub prevails in shaded depressions and along streams generated by snowmelt waters. 
• Experiencing dry arctic conditions, this scrub features shrubs and pasture areas but lacks trees. 
• Characteristic plants include Juniperus Wallichiana, Lonicera spp., and Potentilla spp. 
• This region is home to giant, endangered species such as Snow Leopards, Tibetan Wolves, and various mountain goats and sheep.

Frequently Asked Questions (FAQs) - India's Diverse Forests

1. What percentage of India's geographical area is covered by forests and trees?

Ans. India's total forest and tree cover encompass 24.56% of the country's overall geographical area.

2. How is the term 'forest' defined in India, and who has the authority to define it?

Ans. As of now, there is no specific nationwide definition of the term 'forest' in India. The responsibility lies with individual states, and the Supreme Court's ruling in the T.N. Godavarman Thirumulkpad vs the Union of India case in 1996 affirmed the states' authority to establish the criteria for identifying forests.

3. What is the significance of Sir HG Champion's work in forest classification in India?

Ans. Sir HG Champion made a pioneering effort in the classification of India's forest types with his monumental work, 'Preliminary Survey of Forest Type of India and Burma' in 1936. In 1968, he, along with Seth, presented an updated classification in 'A Revised Survey of the Forest Kinds of India,' considering factors like climate, vegetation, species composition, and more.

4. How are India's forests categorized, and what factors are considered in their classification?

Ans. India's forests are broadly categorized into six "major groupings" ranging from tropical to alpine regions. Within these, there are 16 sub-groups based on specific temperature and moisture regimes. The classification considers factors such as climate, physiognomy, species composition, phenology, terrain, soil characteristics, altitude, aspect, and biotic factors.

5. Can you provide an overview of Tropical Wet Evergreen Forests in India?

Ans. Tropical Wet Evergreen Forests are located in southern states and the northeastern region, boasting high annual rainfall, temperatures between 25-27°C, and humidity around 77%. These forests are characterized by minimal undergrowth, infrequent litter, and host valuable species like mahogany, mesua, white cedar, jamun, canes, and bamboo.

6. Where can Tropical Semi-Evergreen Forests be found, and what are their characteristics?

Ans. Tropical Semi-Evergreen Forests function as a transitional zone between wet evergreen and deciduous forests. They are located along the Western coast, Assam, lower slopes of the Eastern Himalayas, Odisha, and Andaman Island. With an annual rainfall of 200-250 cm and an average temperature of 24-27°C, these forests feature teak, jamun, cashew, hog plum, coral tree, jasmine, and diverse wildlife.

7. Which regions in India are known for Tropical Moist Deciduous Forests, and what species are found there?

Ans. Tropical Moist Deciduous Forests are widespread in India, except in the western and northwestern regions. They house economically significant species like Sal, Adina Cardifolia (Kusum), Xylia Xylocarpa, Anogeissus Iatifolia (Dhau), and Machilus Villosa. The endangered Hoolok Gibbon finds its habitat in these forests, particularly in Manipur.

8. What are Littoral and Swamp Forests, and where are they abundant in India?

Ans. Littoral and Swamp Forests are abundant across India, found in areas such as Deccan Plateau reservoirs, Gujarat's saline coast, Rajasthan's saline coast, the Gulf of Kutch, Eastern Coast Deltas, Kashmir's lakes and rivers, and North East India's swamps. These evergreen swamp forests support a productive mangrove ecosystem.

9. Where can Tropical Thorn Forests be primarily located, and what is their characteristic vegetation?

Ans. Tropical Thorn Forests are primarily located in northern India and some drier areas of the Deccan Plateau. Enduring an annual rainfall of less than 70 cm, they are dominated by stunted Acacia species, including Prosopis, Grewia, Salvadora, Zizyphus, Anogeissus, Gardenia, Capparis, and Carissa.

10. What is unique about Subtropical Pine Forests in northeast India, and which trees dominate this ecosystem?

Ans. Subtropical Pine Forests cover a significant elevation range of 800 to 2000 meters in northeast India's hilly states. Dominated by trees such as Shisham, Teak, Sal, Pine, Fir, Juniper, and Rhododendron, these forests lack stable populations of large carnivores due to scarce wild prey.

11. Where are Subtropical Dry Evergreen Forests found, and what are the key characteristics of this ecoregion?

Ans. Subtropical Dry Evergreen Forests are found in the western Himalayas, Bhabar, and Shiwaliks up to 1000 meters above sea level. Enduring an annual rainfall of 800 millimeters, this ecoregion supports globally threatened species like the Lesser Florican and features diverse bird life.

12. What are the defining features of Montane Wet Temperate Forests, and where are they distributed in India?

Ans. Montane Wet Temperate Forests occur on moderate-height mountains, specifically in the southern parts of India, including Kerala and Tamil Nadu's upper mountainous areas. Characterized by trees like Cullenia Exarillata, Mesua Ferrea, Palaquium Ellipticum, Gluta Travancorica, and Nageia Wallichiana, these forests are home to endemic species.

13. Can you elaborate on the characteristics of the Himalayan Moist Temperate Forests and the species they support?

Ans. Extending the entire length of the Himalayan mountain range, Himalayan Moist Temperate Forests grow between 1500 and 3300 meters above sea level. These forests receive 150 to 250 cm of annual rainfall and house diverse species like pines, cedars, silver firs, spruce, Royal Bengal Tiger, Barking Deer, and Himalayan Black Bear.

14. What is unique about the Himalayan Dry Temperate Forests, and which endangered wildlife inhabits this ecoregion?

Ans. Occupying middle altitudes in the Himalayas, Himalayan Dry Temperate Forests feature an open evergreen forest with an undergrowth of open scrub. Endangered wildlife such as the Snow Leopard, Tibetan Wolf, Tibetan Argali, and Black-necked Crane inhabit this ecoregion.