UPSC Prelims 2015 Q72: Geography – Biogeography & Natural Vegetation
Consider the following States:
1. Arunachal Pradesh
2. Himachal Pradesh
3. Mizoram
In
which of the above States do ‘Tropical Wet Evergreen Forests’ occur?
- (a) 1 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3
Answer: (c) 1 and 3 only
Explanation
Tropical Wet Evergreen Forests
These forests need rainfall above 200 cm and warm weather all year.
| State | Tropical Wet Evergreen Forests? | Reason |
|---|---|---|
| 1. Arunachal Pradesh | Yes | Heavy rain in the lower hills |
| 2. Himachal Pradesh | No | Has temperate and alpine forests |
| 3. Mizoram | Yes | Heavy rain in the north-eastern hills |
Where they occur in India:
| Region | Examples |
|---|---|
| Western Ghats | Western slopes in Kerala and Karnataka |
| North-East | Arunachal Pradesh, Assam, Meghalaya, Mizoram, Nagaland |
| Islands | Andaman and Nicobar |
Features: tall trees up to 60 metres, several layers, no common leaf-fall season; trees such as rosewood, mahogany, ebony.
Answer: (c) 1 and 3 only.
Why each option is right or wrong
- (a) Incorrect. Mizoram also has tropical wet evergreen forests.
- (b) Incorrect. Himachal Pradesh has temperate forests, not tropical wet evergreen.
- (c) CORRECT. Arunachal Pradesh and Mizoram have tropical wet evergreen forests.
- (d) Incorrect. Himachal Pradesh lacks the heat and rain for such forests.
Key point
Tropical wet evergreen forests: rainfall above 200 cm; Western Ghats, North-East (Arunachal Pradesh, Mizoram) and Andaman and Nicobar Islands.
Remember
Wet evergreen: Western Ghats, North-East, Andamans.
Common mistakes
- Thinking any forested hill State has evergreen rain forest.
- Forgetting the 200 cm rainfall threshold.
- Confusing tropical evergreen with Himalayan coniferous forests, which are also green all year.
Exam tip
Tropical wet evergreen = hot + very wet. The western Himalaya is neither tropical nor wet enough.
Sources
- NCERT Class XI — India: Physical Environment, Ch 5 (Natural Vegetation)
- Forest Survey of India — India State of Forest Report (forest type groups)