RAS question
Which of the following INCORRECTLY describes a feature of saline soil reclamation in Rajasthan?
Correct answer: (C) Deep ploughing alone (without any chemical amendment) is sufficient to permanently reclaim saline-alkali soils around Sambhar..
Deep ploughing alone, without chemical amendment, is not sufficient to permanently reclaim saline-alkali soils around Sambhar.
Explanation
Saline-alkali soil reclamation is not just a tillage problem. Deep ploughing may break a hard layer and improve movement of water for a short period, but it does not remove the exchangeable sodium that damages soil structure. The ICAR-CSSRI technology note treats reclamation as a combined process: gypsum is applied to sodic soil, mixed into the surface layer, and irrigation water is then used to leach salts downward. ICAR-CSSRI also identifies subsurface drainage as an effective technology for removing excess water and salts from saline irrigated lands, including adoption in Rajasthan. So option C is incorrect because it presents a mechanical operation as a permanent cure, while the required approach combines gypsum, leaching, drainage and salt-tolerant cropping or bio-remediation.
Why the other options are wrong
- (A) Option A describes a valid feature of reclamation because gypsum supplies calcium that replaces exchangeable sodium and helps restore soil aggregation.
- (B) Option B is valid because leaching with irrigation water is used to move accumulated salts below the root zone, provided drainage prevents waterlogging.
- (D) Option D is valid because salt-tolerant crops and bio-remediation crops are used during early reclamation to work with partially improved saline soils.
Concept
This tests soil degradation and reclamation in Rajasthan geography, especially the distinction between saline, sodic and saline-alkali land management. RAS repeats it because areas such as Sambhar make soil salinity a recurring agriculture-and-environment issue.