Environment and Ecology
India – world’s second-largest emitter of N₂Os
▪ India, the world’s second-largest emitter of N₂O after China, faces climate risks as N₂O has 300 times the global warming potential of CO₂.
▪ Nitrogen is the most abundant atmospheric gas, constituting ~78% of Earth’s atmosphere.
▪ Atmospheric nitrogen (N₂) is inert and unusable by plants or animals.
▪ Plants rely on diazotrophs (N-fixing bacteria) through symbiotic association (e.g., in legumes).
▪ Nitrifying bacteria convert ammonia into nitrites (NO₂⁻) and then nitrates (NO₃⁻) – the form plants can absorb.
✓ Nitrification: Ammonia → Nitrites → Nitrates (plant-usable form).
▪ Denitrification returns excess nitrates back to the atmosphere, maintaining the natural nitrogen cycle.
