Indian Geography — Natural Vegetation
1. Tropical Evergreen Forests
Context: Tropical evergreen forests are dense, multi-layered forests found in areas with high rainfall and temperature.
- Location: Western slope of the Western Ghats, hills of the north-eastern region and the Andaman and Nicobar Islands.
- Annual Precipitation: Over 200 cm.
- Mean Annual Temperature: 22°C.
- Tree Species: Rosewood, Mahogany, Aini, Ebony, etc.
📝 UPSC Previous Year Questions:
- UPSC Prelims 2019: Tropical evergreen forests are found in which regions? Answer: Western Ghats, NE hills, Andaman & Nicobar.
- UPSC Prelims 2017: Which tree species are found in tropical evergreen forests? Answer: Rosewood, Mahogany, Ebony.
2. Tropical Deciduous Forests / Monsoon Forests
Context: Tropical deciduous forests are the most widespread forests in India, also known as Monsoon forests.
- Location: Areas with rainfall of 70-200 cm.
Moist Deciduous Forests
- Location: North-eastern states along the foothills of Himalayas, eastern slopes of the Western Ghats and Odisha.
- Rainfall: 100-200 cm.
- Tree Species: Teak, Sal, Shisham, Hurra, Mahua, Amla, Semul, Kusum, Sandalwood, etc.
Dry Deciduous Forests
- Location: Rainier areas of the Peninsula and the plains of Uttar Pradesh and Bihar.
- Rainfall: 70-100 cm.
- Tree Species: Tendu, Palas, Amaltas, Bel, Khair, Axlewood, etc.
📝 UPSC Previous Year Questions:
- UPSC Prelims 2018: Which is the most widespread forest type in India? Answer: Tropical Deciduous Forests.
- UPSC Prelims 2016: Teak and Sal are found in which type of forests? Answer: Moist Deciduous Forests.
3. Semi Evergreen Forests
- Feature: Mixture of evergreen and moist deciduous trees.
- Tree Species: White cedar, Hollock, Kail.
4. Tropical Thorn Forests
Context: Tropical thorn forests are found in semi-arid areas with very low rainfall.
- Location: Semi-arid areas of southwest Punjab, Haryana, Rajasthan, Gujarat, Madhya Pradesh and Uttar Pradesh.
- Rainfall: Less than 50 cm.
- Tree Species: Babool, Ber, Wild date palm, Khair, Neem, Khejri, Palas.
- Features:
- Plants remain leafless for most part of the year and give an expression of scrub vegetation.
- Tussocky grass grows up to a height of 2 meters.
📝 UPSC Previous Year Questions:
- UPSC Prelims 2015: Thorn forests are found in which regions? Answer: Semi-arid areas of Rajasthan, Gujarat, Haryana, etc.
5. Montane Forests
Northern Mountain Forests
- Location: Himalayan Ranges.
- Features:
- Deciduous Forests: Foothills of Himalayas.
- Wet Temperate: Higher hill areas of West Bengal and Uttarakhand.
- Practice of transhumance: Tribes like Gujjars, Bakarwals, Bhotiyas, and Gaddis.
- Tree Species: Oak, Chestnut, Pine, Chir, Deodar, Silverfirs, Junipers, Birch, Rhododendrons, etc.
Southern Mountain Forests
- Location: Western Ghats, the Vindhyas and the Nilgiris.
- Features: Temperate forests are called Sholas in the Nilgiris, Anaimalai, and Palani hills.
- Tree Species: Magnolia, Laurel, Cinchona, Wattle.
📝 UPSC Previous Year Questions:
- UPSC Prelims 2018: Sholas are found in which region? Answer: Nilgiris, Anaimalai, Palani hills.
- UPSC Prelims 2016: Which tribes practice transhumance in Himalayan regions? Answer: Gujjars, Bakarwals, Bhotiyas, Gaddis.
6. Mangrove Forests
Context: Mangrove forests are coastal wetlands found in tropical and subtropical regions.
- Location: Andaman and Nicobar Islands, Sunderbans of West Bengal, Mahanadi, Godavari and Krishna deltas.
- Area: Spread over 6,740 sq. km which is 7 per cent of the world's mangrove forests.
📝 UPSC Previous Year Questions:
- UPSC Prelims 2020: Sunderbans is known for which type of forest? Answer: Mangrove forests.
- UPSC Prelims 2017: Mangrove forests are found in which deltas? Answer: Mahanadi, Godavari, Krishna deltas.
7. Summary: Natural Vegetation at a Glance
| Forest Type | Location | Rainfall | Key Species | UPSC Year |
|---|---|---|---|---|
| Tropical Evergreen | Western Ghats, NE, A&N | >200 cm | Rosewood, Mahogany, Ebony | 2017, 2019 |
| Moist Deciduous | NE, Eastern Ghats, Odisha | 100-200 cm | Teak, Sal, Shisham, Mahua | 2016, 2018 |
| Dry Deciduous | Peninsula, UP, Bihar plains | 70-100 cm | Tendu, Palas, Amaltas, Bel | — |
| Thorn Forest | Rajasthan, Gujarat, Haryana | <50 cm | Babool, Ber, Khejri, Neem | 2015 |
| Montane (Northern) | Himalayan Ranges | — | Oak, Pine, Deodar, Rhododendron | 2016, 2018 |
| Montane (Southern) | Western Ghats, Nilgiris | — | Sholas, Magnolia, Cinchona | 2018 |
| Mangrove | Sunderbans, deltas, A&N | — | Sunderbans (largest) | 2017, 2020 |
Key Takeaways for UPSC
- Tropical Evergreen: Western Ghats, NE, A&N; >200 cm rainfall; Rosewood, Mahogany — UPSC 2017, 2019
- Moist Deciduous: Most widespread; 100-200 cm; Teak, Sal, Shisham — UPSC 2016, 2018
- Dry Deciduous: 70-100 cm; Tendu, Palas, Bel — Peninsula, UP, Bihar plains
- Thorn Forests: <50 cm; Babool, Ber, Khejri — Rajasthan, Gujarat, Haryana — UPSC 2015
- Montane Forests: Sholas in Nilgiris; Transhumance by Gujjars, Bakarwals, Bhotiyas — UPSC 2016, 2018
- Mangrove Forests: 7% of world's mangroves; Sunderbans largest — UPSC 2017, 2020
High-Yield Interactive UPSC Quiz (Natural Vegetation)
Q1. Tropical evergreen forests are found in which of the following regions?
Correct Answer: B. Tropical evergreen forests are found in the western slope of the Western Ghats, hills of the north-eastern region, and the Andaman and Nicobar Islands. (UPSC 2019)
Q2. Which is the most widespread forest type in India?
Correct Answer: B. Tropical Deciduous forests are the most widespread forests in India, also known as Monsoon forests. (UPSC 2018)
Q3. Teak and Sal are found in which type of forests?
Correct Answer: B. Teak, Sal, Shisham, and Mahua are found in Moist Deciduous forests, which receive rainfall between 100-200 cm. (UPSC 2016)
Q4. Thorn forests are found in areas with rainfall less than:
Correct Answer: C. Thorn forests are found in semi-arid areas with rainfall less than 50 cm, such as Rajasthan, Gujarat, and Haryana. (UPSC 2015)
Q5. Sholas are a type of temperate forest found in:
Correct Answer: C. Sholas are temperate forests found in the Nilgiris, Anaimalai, and Palani hills of Southern India. (UPSC 2018)
Q6. Which tribes practice transhumance in the Himalayan region?
Correct Answer: B. Gujjars, Bakarwals, Bhotiyas, and Gaddis practice transhumance in the Himalayan region. (UPSC 2016)
Q7. Mangrove forests in India are spread over approximately what area?
Correct Answer: C. Mangrove forests in India are spread over 6,740 sq. km, which is 7% of the world's mangrove forests. (UPSC 2017)
Q8. The largest mangrove forest in the world is located in:
Correct Answer: C. The Sunderbans in West Bengal is the largest mangrove forest in the world. (UPSC 2020)
Q9. Which tree species is NOT found in tropical evergreen forests?
Correct Answer: C. Teak is found in Moist Deciduous forests, not in Tropical Evergreen forests. Tropical Evergreen forests have Rosewood, Mahogany, and Ebony. (UPSC 2017)
Q10. Dry Deciduous forests receive rainfall between:
Correct Answer: B. Dry Deciduous forests receive rainfall between 70-100 cm and are found in the rainier areas of the Peninsula and the plains of Uttar Pradesh and Bihar.