Due to their extensive rice cultivation, some regions may be contributing to global warming. To what possible reason/reasons is this attributable? Which of the statements given above is/are correct?

Answer: (c) Both 1 and 2

Both gases are emitted from rice cultivation.

Statement by statement

1. ✓ CORRECT Flooded paddy soil lacks oxygen, so methanogens make methane.

2. ✓ CORRECT Nitrogen fertilisers lead to N₂O emissions from soil.

The idea

A flooded rice field is a man-made swamp. Water cuts the soil off from air. In soil without oxygen, a group of microbes (methanogens) break down organic matter and release methane, which escapes through the rice plant’s stem.

Field is flooded → No oxygen in the soil → Methanogens become active → Methane is produced → It escapes through the plant into the air

Also know

Nitrous oxide is a different story: soil microbes turn part of any nitrogen fertiliser into N₂O. Over 100 years methane is about 28 times and nitrous oxide about 270 times as strong as carbon dioxide. Alternate wetting and drying cuts methane but can raise N₂O. Cutting both needs careful water and nitrogen management; neem-coated urea releases nitrogen slowly. In India the largest farm source of methane is cattle digestion, followed by rice.