UPSC CSE Prelims
Question 25
What can be the impact of excessive/inappropriate use of nitrogenous fertilizers in agriculture?
- Proliferation of nitrogen-fixing microorganisms in soil can occur.
- Increase in the acidity of soil can take place.
- Leaching of nitrate to the ground-water can occur.
Select the correct answer using the code given below.
View correct answer and explanation
Correct answer: C
Correct Option: C
Explanation: Overapplication of nitrogen fertilisers can acidify soil and lead to nitrate leaching, while abundant available nitrogen generally reduces the need for biological nitrogen fixation.
Statement/Pair-wise Analysis:
Statement/Item 1: Incorrect - High mineral nitrogen commonly suppresses biological nitrogen fixation rather than promoting proliferation of nitrogen fixers.
Statement/Item 2: Correct - Nitrification releases hydrogen ions and can increase soil acidity.
Statement/Item 3: Correct - Nitrate is soluble and can leach from soils into groundwater.
Option-wise Analysis:
A: Incorrect - includes incorrect statement/item 1; omits correct statement/item 2.
B: Incorrect - omits correct statement/item 3.
C: Correct - includes all and only the correct items.
D: Incorrect - includes incorrect statement/item 1.