Explain Nitrogen Cycle in detail.
Answers
Air contains a major amount (78%) of nitrogen as its component. However, plants cannot use it directly in this form. The Rhizobium bacteria present in root nodules of leguminous crops (peas, soybeans, etc.) take the nitrogen from the air and converts it into the form (ammonia) that can be used by the plants. This process of conversion of atmospheric nitrogen to ammonia is called nitrogen fixation.
The nitrogen fixed by these bacteria is taken up by the plants and stored in their tissues as plants proteins. This nitrogen passes in the form of proteins to the herbivores, carnivores and omnivores. When plants and animals die, they are decomposed by bacteria. The nitrogen compounds and other nutrients are returned to the soil. Some of the nitrogen compounds are reabsorbed by the plants and some are converted to nitrogen by a special bacteria present in the soil. This free nitrogen returns to the air.
In this way, atmospheric nitrogen flows between the soil and organisms. This is called nitrogen cycle. Thus, the nitrogen cycle can be defined as a cycle flows of atmospheric nitrogen between the soil and living organisms and returning to the atmospheric again.
