RAS question
Which river is known as 'the lifeline of Rajasthan's desert'?
Correct answer: (B) Luni.
The Luni is known as the lifeline of Rajasthan's desert, especially the Thar region of western Rajasthan.
Explanation
Luni is called the lifeline of the Thar Desert because it is the major river system associated with western Rajasthan's arid tract. It passes through Ajmer, Nagaur, Pali, Jodhpur, Barmer and Jalore in the desert-side geography of Rajasthan. The Central Water Commission, Water Year Book 2018-19: Mahi, Sabarmati & Other West Flowing Rivers describes Luni as the only river basin of any significance in western Rajasthan, says it originates near Ajmer on the western slopes of the Aravali ranges, flows south-west for 511 km in Rajasthan, and finally reaches the Rann of Kachchh. That combination of western Rajasthan location, desert relevance and basin significance makes Luni the correct answer.
Why the other options are wrong
- (A) Ghaggar is seasonal in northern Rajasthan, so it is not the major western Rajasthan desert river system associated with Luni.
- (C) Banas is associated with the eastern part of Rajasthan, whereas the desert-side lifeline is linked to western Rajasthan.
- (D) Chambal flows in south-eastern Rajasthan, not through the Thar Desert belt where Luni is known as the lifeline.
Concept
Rajasthan drainage has a sharp contrast between the arid western basins and the better-watered eastern and south-eastern river systems. River-basin location connects physical geography with districts and regional identity.