Question

The diagram shows a simplified nitrogen cycle. Which process is responsible for returning nitrogen to the air?

Answer 1

In the nitrogen cycle, the process responsible for returning nitrogen to the air is called **denitrification**. During denitrification, bacteria convert nitrates and nitrites in the soil back into nitrogen gas (N₂), which is then released into the atmosphere. This process helps to close the nitrogen cycle by removing excess nitrogen from the soil and reintroducing it to the air.