UPSC CSE Prelims
Question 21
Among the following crops, which one is the most important anthropogenic source of both methane and nitrous oxide ?
View correct answer and explanation
Correct answer: B
Correct Option: B (Rice)
Explanation: Flooded paddy fields foster methane-producing anaerobic microbes; nitrogen fertilisers and alternating wet/dry conditions also contribute nitrous oxide.
Option-wise Analysis:
A. Incorrect-Cotton can produce N₂O from fertiliser but is not a leading methane-producing crop.
B. Correct-rice cultivation is a major agricultural source of CH₄ and can release N₂O as well.
C. Incorrect-Sugarcane contributes fertiliser-related N₂O but its fields are not a comparable global CH₄ source.
D. Incorrect-Wheat farming can emit N₂O but usually lacks prolonged anaerobic flooding needed for major CH₄ emissions.