'Oxides of nitrogen namely nitrous oxide, are released into the atmosphere from varied sources'. Explain the statement with relevant sources.

Oxides of nitrogen (namely nitrous oxide), are released into the atmosphere from various natural and man-made sources. The natural sources are:

1. Anaerobic respiration — Activities of micro organisms in soil release nitrogen, nitric oxide and nitrous oxide.
2. The lightning discharge in the atmosphere creates high temperatures causing Nitrogen (N₂) and Oxygen (O₂) to combine forming Oxides of Nitrogen.

The man-made sources are:

1. Use of nitrogenous fertilizers for agricultural activities release oxides of nitrogen.
2. Automobile exhausts.
3. Burning of biomass.