What is meant by nitrogen fixation
Nitrogen fixation is the process of conversion of molecular nitrogen (N2) into ammonia (NH3).
There are two methods that change atmospheric nitrogen into usable forms through the process of nitrogen fixation:
. During lightning and thunder, the high temperature and pressure in the air convert atmospheric nitrogen into oxides of nitrogen that can dissolve in water to produce nitric and nitrous acids. These fall along with rain.
. Certain forms of bacteria are able to convert atmospheric nitrogen into usable forms such as nitrates and nitrites. Such nitrogen fixing bacteria are commonly found in the roots of legumes (plants of pulses) inside special structures called root nodules.
These usable forms of nitrogen are absorbed by plants to produce many compounds such as amino acids, which in turn form proteins.