Question

Which of the following are true for Tropical Thorn Forests?

1. They occur in areas with rainfall less than 50 cm.

2. Vegetation includes tussocky grass up to 2 meters high.

3. These forests are found in the northeastern hills and Andaman & Nicobar Islands.

• A. 1 and 3
• B. 1 and 2
• C. 2 and 3
• D. 1, 2, and 3

Answer 1

Answer:

B. 1 and 2

Tropical Thorn Forests Characteristics:

• Rainfall: These forests are typically found in regions receiving less than 50 cm of annual rainfall. This low rainfall is a defining characteristic that dictates the type of vegetation that can survive.
• Vegetation Type: The dominant vegetation consists of thorny trees and shrubs, along with tussocky grasses. These grasses can grow up to 2 meters in height in areas where they are sustained.
• Adaptations: Plants in these forests exhibit adaptations to arid conditions, such as deep root systems, small leaves (or modified leaves like spines) to reduce water loss through transpiration, and thick bark.
• Geographical Distribution in India: Tropical Thorn Forests are primarily located in the arid and semi-arid regions of northwestern India, including parts of Rajasthan, Gujarat, and Madhya Pradesh. They are NOT typically found in the northeastern hills or the Andaman & Nicobar Islands, which have significantly higher rainfall and different forest types (like rainforests and mangrove forests, respectively).

Distinguishing Features for Exams:

• Contrast with Other Forests: It's important to differentiate thorn forests from other Indian forest types. For instance, northeastern hills are known for evergreen forests, and Andaman & Nicobar Islands host tropical rainforests and tidal forests.
• Rainfall Threshold: The 50 cm rainfall mark is a crucial figure often tested in exams to identify thorn forest regions.
• Vegetation Structure: The presence of thorny, scattered trees and tall grasses is a key visual and ecological characteristic.