Which of the following statements with reference to saline soil in India is/are correct ? 1. They are rich in nitrogen. 2. They occur in arid and semi-arid regions, and in waterlogged and swampy areas. Select the answer using the code given below :
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
Correct answer
Explanation
The correct answer is B, 2 only. Saline soils are found in dry regions and in waterlogged or swampy areas, but they are poor in nitrogen, not rich in it.
Saline soils, also called usara soils, contain a large share of sodium, potassium and magnesium salts. In arid and semi-arid areas strong evaporation draws salty water up through the soil, and in waterlogged and swampy areas poor drainage lets salts collect; over-irrigation in canal areas of Punjab and Haryana has made the problem worse. They are infertile, lack nitrogen and calcium, and are treated by adding gypsum and growing salt-tolerant crops.
Option A is wrong because statement 1 is false: these soils are deficient in nitrogen. Option C is wrong because only statement 2 is correct. Option D is wrong because statement 2 correctly describes where they occur.
Exam tip: saline (usara, reh, kallar) soils lack nitrogen and calcium; the remedy is gypsum.
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