Describe five instances in the nitrogen cycle where bacterial action is important

Some stages of the nitrogen cycle where bacteria have a high significance are:

1) Nitrogen fixing in the root nodules of legumes

Nitrogen fixing bacteria reside in the root nodules of leguminous plants, where they fix atmospheric nitrogen into forms of nitrogen usable by the plant.

2) Nitrogen fixation in the soil

Some nitrogen fixing bacteria live in the soil, converting atmospheric nitrogen to usable forms.

3) Decomposition

Bacteria also play a role in decomposing organic matter, where the complex nitrogen containing compounds present within organisms are converted to simpler forms of nitrogen and released into the soil

4) Nitrification

Bacteria present in the soil convert ammonium ions to nitrite ions

Moreover, other bacteria convert nitrite ions to nitrate ions

5) Denitrifying bacteria

These bacteria convert nitrogen in the soil to atmospheric nitrogen and release it from the soil