Question

Assertion (A): Montane Forests show a change in vegetation with increasing altitude.

Reason (R): Temperature decreases as altitude increases, affecting the type of vegetation.

• A. Both A and R are true, and R is the correct explanation of A.
• B. Both A and R are true, but R is not the correct explanation of A.
• C. A is true, but R is false.
• D. A is false, but R is true.

Answer 1

Answer:

A. Both A and R are true, and R is the correct explanation of A.

Montane Forests: Vegetation and Altitude Correlation

• Assertion (A) states that Montane Forests exhibit a noticeable change in their vegetation as the altitude increases. This is a fundamental characteristic of these forest types found in mountainous regions.
• Reason (R) correctly explains this phenomenon by stating that temperature is inversely proportional to altitude. As one ascends higher in elevation, the ambient temperature drops significantly.
• This decrease in temperature directly influences the type of plant life that can thrive at different altitudes. Different species have specific temperature ranges within which they can survive and reproduce.
• Vegetation Zones in Montane Forests:
  1. Lower Montane (Temperate) Forests: Found at lower elevations, these forests typically have broad-leaved evergreen trees, with temperate deciduous trees at higher elevations within this zone.
  2. Higher Montane (Subalpine) Forests: As altitude increases further, temperatures become cooler, favoring the growth of coniferous trees like pines, firs, and spruces.
  3. Alpine Scrub and Meadows: At the highest altitudes, the temperature is too cold for trees to grow. Vegetation is limited to shrubs, grasses, and wildflowers, forming alpine meadows.
• Example: In the Himalayas, one can observe this altitudinal zonation. Tropical evergreen forests are found at the foothills, gradually giving way to temperate forests, then coniferous forests, and finally alpine meadows as one climbs higher.
• The correlation between altitude, temperature, and vegetation type is a crucial concept in understanding biogeography and the distribution of plant and animal life in mountainous ecosystems. This principle applies to montane forests across the globe.