RAS question
Alpine vegetation in India is found at elevations above:
Correct answer: (B) 3600 metres.
In India, alpine vegetation in the Himalayas is found above about 3600 metres.
Explanation
Alpine vegetation forms the highest Himalayan vegetation belt. Above about 3600 metres, alpine vegetation begins to replace temperate forests and grasslands. Near the lower boundary of this belt, trees such as silver fir, juniper, pine and birch are found; toward the snowline, they become progressively stunted, followed by shrubs, mosses, lichens and alpine meadows, which are locally called bugyals. The Ministry of Environment, Forest and Climate Change, Government of India describes subalpine and alpine vegetation in the 3500-5000 metre zone, where tree species are generally absent and shrubby plants occur in the lower parts. Above 4000 metres, the alpine zone remains snow-covered for much of the year and vegetation is scarce; above 5000 metres, permanent snow takes over. Therefore, 3600 metres is the best answer among the options because it marks the transition into the alpine Himalayan belt rather than a lower tropical, subtropical or temperate forest zone.
Why the other options are wrong
- (A) 500 metres is far too low because this height falls in the tropical belt, not in the Himalayan alpine belt.
- (C) 2000 metres does not fit because that level corresponds to temperate forests rather than alpine vegetation.
- (D) 1000 metres is below the alpine zone because it falls in the subtropical forest belt.
Concept
This tests altitude-based vegetation zonation in Indian geography. RAS asks this idea repeatedly because Himalayan relief directly links elevation with climate, forest type and ecological distribution.