What are the stages of the nitrogen cycle?

The nitrogen cycle is the biogeochemical cycle. The stages of the nitrogen cycle are given below:

• Nitrogen fixation: The process of conversion of nitrogen (N2 ) to ammonia is termed nitrogen fixation. Normally, bacteria change nitrogen into ammonium.
• Nitrification: Ammonia is first oxidised to nitrite by the bacteria Nitrosomonas and/or Nitrococcus. The nitrite is further oxidised to nitrate with the help of the bacterium Nitrobacter. These steps are called nitrification.
• Assimilation: Plants absorb nitrates from the soil into their roots. Then nitrogen gets used in chlorophyll, nucleic acids, and amino acids.
• Ammonification: When a plant or animal expires, decomposers such that bacteria and fungi turn the nitrogen back into ammonium.
• De-nitrification:It is the microbial process of reducing nitrate and nitrite to gaseous forms of nitrogen, principally nitrous oxide (N2O) and nitrogen (N2).

Further Reading:

• The Nitrogen Cycle
• Geography Notes