UPSC CSE Prelims
Question 98
With reference to agricultural soils, consider the following statements :
- A high content of organic matter in soil drastically reduces its water holding capacity.
- Soil does not play any role in the sulphur cycle.
- Irrigation over a period of time can contribute to the salinization of some agricultural lands.
Which of the statements given above is/are correct ?
View correct answer and explanation
Correct answer: B
Correct Option: B
Explanation: Soil organic matter generally increases aggregation and moisture retention; soil is important in sulphur cycling through microbes and mineral processes. Repeated irrigation without proper drainage can concentrate salts in farmland.
Statement/Pair-wise Analysis:
Statement/Item 1: Incorrect - Higher organic matter generally increases, rather than drastically reduces, soil water-holding capacity.
Statement/Item 2: Incorrect - Soil microbes and mineral transformations are integral to the sulphur cycle.
Statement/Item 3: Correct - Evaporation and inadequate drainage under repeated irrigation can produce soil salinisation.
Option-wise Analysis:
A: Incorrect - includes incorrect statement/items 1, 2; omits correct statement/item 3.
B: Correct - includes all and only the true statements/items.
C: Incorrect - includes incorrect statement/item 1.
D: Incorrect - includes incorrect statement/items 1, 2.