In the Himalayan mountains different types of vegetation are found.

Question

Given below are two statements, one is labelled as Assertion (A) and the other as Reason (R).

Assertion (A): In the Himalayan mountains different types of vegetation are found.

Reason (R): In Himalayas, there are variations in climate with change in altitude.

Select the correct answer from the code given below:

1. A. Both (A) and (R) are true, but (R) is not the correct explanation of (A)
2. B. (A) is false, but (R) is true
3. C. (A) is true, but (R) is false
4. D. Both (A) and (R) are true and (R) is the correct explanation of (A) (Correct answer)

Correct Answer

Option D — Both (A) and (R) are true and (R) is the correct explanation of (A)

Detailed Solution & Explanation

The correct answer is Both (A) and (R) are true and (R) is the correct explanation of (A).

Key Points

• Assertion is true. The Himalayas show a striking range of vegetation types within short horizontal distances — tropical deciduous at the foot, then subtropical pine, temperate broadleaf and conifer, and finally alpine meadows and tundra.
• Reason is true. Temperature falls with increasing altitude (the normal lapse rate is about 6.5°C per 1,000 m), and rainfall also varies with height and aspect.
• (R) explains (A) exactly: the vegetation belts exist *because* climate changes with altitude. Hence option (d).

Additional Information

• The Himalayan vertical sequence, from the base upward: Tropical deciduous → Subtropical pine (chir) → Temperate wet/broadleaf (oak, chestnut) → Temperate conifer (deodar, spruce, fir) → Sub-alpine → Alpine meadows (bugyal/marg) → Snowline.
• Altitudinal zonation mirrors latitudinal zonation — climbing a mountain reproduces, in a few kilometres, the vegetation change one would meet travelling from the equator to the poles.
• Above the treeline, alpine grasslands are called Bugyal in Uttarakhand and Marg in Kashmir (as in Gulmarg, Sonmarg).