
Consider the following statements:
- Agricultural soils release nitrogen oxides into the environment.
- Cattle release ammonia into the environment.
- Poultry industry releases reactive nitrogen compounds environment.
Which of the statements given above is/are correct?
- 1 and 3 only
- 2 and 3 only
- 2 only
- 1, 2 and 3
Explanation
Statement 1 is correct
- Soils are a major source of nitrogen emissions, specifically nitrogen oxides (NOx) and nitrous oxide (N₂O). This emission primarily results from the application of chemical fertilizers (especially urea) and biological processes such as nitrification and denitrification. These emissions result from inefficient nitrogen use by crops, with about 80% of nitrogen inputs wasted, leading to air and water pollution. Nitrogen oxides (NOx: nitric oxide and nitrogen dioxide) are particularly concerning because they contribute to the formation of PM2.5 particles, which are closely linked to cardiovascular and respiratory illnesses.
- Additionally, these nitrogen oxides contribute to winter smog in North India, with crop residue burning being a significant source.

Image Source: The Hindu
Statement 2 is correct
- The provided data from the Indian Nitrogen Assessment confirms that cattle account for 80% of ammonia emissions in India. India is currently the largest global source of ammonia emissions, producing almost twice as much ammonia as nitrogen oxides (NOx). However, given the current growth trend in NOx emissions from sources such as fossil fuel combustion, NOx emissions are expected to exceed ammonia emissions by 2055.
Statement 3 is correct
- The poultry industry is a source of reactive nitrogen compounds. Reactive nitrogen compounds (RNCs) are forms of nitrogen, like ammonia (NH₃), nitrous oxide (N₂O), and nitrogen oxides (NOx), that are highly reactive in the environment.

