RAS question
Soil erosion by wind is most common in:
Correct answer: (A) Arid and semi-arid regions of Rajasthan.
Soil erosion by wind is most common in the arid and semi-arid regions of Rajasthan, especially western Rajasthan.
Explanation
Wind erosion, or aeolian erosion, becomes dominant where dry sandy terrain, sparse vegetation and strong winds allow loose topsoil to be lifted and transported. Annals of Arid Zone describes wind erosion as a major problem in the arid sandy tract of north-west India, especially west Rajasthan, and notes a westward increase in erosivity with decreasing rainfall and increasing wind velocity. This matches the standard Rajasthan geography point in the question: arid western Rajasthan, along with parts of Gujarat and Haryana, is the classic zone where wind can remove exposed topsoil. Hence the Rajasthan arid and semi-arid belt is the best answer, not humid or high-rainfall regions where water erosion is more typical.
Why the other options are wrong
- (B) Northeast India is not the best fit because heavy water erosion is more characteristic there than dominant wind erosion.
- (C) The Western Ghats are a high-rainfall region where water erosion, not the aeolian erosion typical of arid western Rajasthan, is more characteristic.
- (D) The Indo-Gangetic Plain mainly faces water erosion, so it does not match the dry, sparsely vegetated conditions needed for dominant wind erosion.
Concept
This tests the Rajasthan geography link between climate, vegetation cover and soil erosion process. It recurs in RAS because western Rajasthan's arid landscape is central to questions on soils, desertification and land degradation.