RAS question
Black cotton soil (regur) in Rajasthan is primarily associated with which region?
Correct answer: (D) Hadoti region (Kota-Jhalawar-Baran).
In Rajasthan, black cotton soil or regur is primarily associated with the Hadoti region of Kota, Jhalawar, Baran and Bundi.
Explanation
Black cotton soil in Rajasthan points to Hadoti, not to western or Aravalli-side regions. The Hadoti belt of Kota, Jhalawar, Baran and Bundi is part of the Deccan Trap, and its regur is rich in lime, iron, magnesia and alumina, making it suitable for cotton, soybean and other crops. Indian Council of Agricultural Research's strategy document links the same region to this soil type: its section on the Humid South-Eastern Plains lists Baran, Bundi, Jhalawar and Kota, then states that the black soil region of the Hadoti plateau is fertile and used for sugarcane, cotton and opium, with soybean among the rainy-season crops. Hadoti therefore fits both the soil type and the Rajasthan regional geography.
Why the other options are wrong
- (A) Marwar, represented here by Jodhpur and Pali, is associated with desert and grey-brown soils, so it does not fit black cotton regur.
- (B) Shekhawati, represented by Sikar and Jhunjhunu, has sandy loam soils rather than black cotton soil.
- (C) Mewar, represented by Udaipur and Rajsamand, is tied to red and brown soils, not to the Hadoti black-soil belt.
Concept
Rajasthan geography links soil type, physiographic region and cropping pattern. RAS often repeats such items because soils, agro-climatic zones and regional crop suitability are core map-based facts.