UPSC Prelims 2013 Q55: Environment & Ecology – Ecosystems & Ecology Concepts
Which of the following is/are unique characteristic/characteristics of equatorial forests?
1. Presence of tall, closely set trees with crowns forming a continuous canopy
2. Coexistence of a large number of species
3. Presence of numerous varieties of epiphytes
Select the correct answer using the codes given below.
- (a) 1 only
- (b) 2 and 3 only
- (c) 1 and 3 only
- (d) 1, 2 and 3
Answer: (d) 1, 2 and 3
Explanation
Characteristics of equatorial forests
| Characteristic | True of equatorial forests? | Detail |
|---|---|---|
| 1. Tall, closely set trees with crowns forming a continuous canopy | Yes | The canopy blocks most sunlight from the ground |
| 2. Coexistence of a large number of species | Yes | The highest biodiversity on land; no single species dominates |
| 3. Numerous varieties of epiphytes | Yes | Orchids, ferns and mosses grow on tree branches |
Other features:
| Feature | Detail |
|---|---|
| Layers | Emergent, canopy, understorey, forest floor |
| Leaves | Evergreen; trees shed leaves at different times |
| Climbers | Lianas hang from tree to tree |
| Trees | Hardwoods such as mahogany, ebony, rosewood |
| Soil | Poor and leached, despite the lush growth |
Where: Amazon basin, Congo basin, Indonesia and Malaysia.
Answer: (d) 1, 2 and 3.
Why each option is right or wrong
- (a) Incorrect. The forests also have many species and many epiphytes.
- (b) Incorrect. The continuous canopy of tall trees is also a feature.
- (c) Incorrect. The coexistence of many species is also a feature.
- (d) CORRECT. All three are characteristics of equatorial forests.
Key point
Equatorial rain forest: continuous canopy in layers, very high species diversity, epiphytes and lianas, evergreen hardwoods, poor leached soil.
Remember
Equatorial forest: canopy, diversity, epiphytes.
Common mistakes
- Thinking rain forest soil is rich; nutrients are held in the plants.
- Confusing epiphytes (grow on trees) with parasites (feed on them).
- Forgetting that trees here occur in mixed stands, not pure ones.
Exam tip
Rain forest = many layers, many species, many plants on plants.
Sources
- G.C. Leong — Certificate Physical and Human Geography (The Hot, Wet Equatorial Climate)
- NCERT Class XI — Fundamentals of Physical Geography, Ch 15 (Life on the Earth)