Question
Explain in brief, the Nitrogen cycle.
✓
Answer
The nitrogen cycle involves the following steps:
- Nitrogen fixation:
- It is the process of conversion of atmospheric free nitrogen into ammonia and other nitrogenous compounds.
- It is carried out by soil microbes like Azotobacter, Azospirillum and Rhizobium.
- Lightning and ultraviolet rays provide energy for conversion of nitrogen into oxides of nitrogen.
- Ammonification: It is the process of decomposition of organic nitrogenous compounds into ammonia.
- Nitrification: It is the process of converting ammonia first into nitrite (by Nitrosomonas, Nitrococcus) and then into nitrate (by Nitrobacter).
- Denitrification:
- It is the process of conversion or reduction of nitrates in the soil to free nitrogen.
- It is carried out by bacteria like Thiobacillus and Pseudomonas.
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