nitrogen fixation(redirected from Nitrate fixation)
Also found in: Thesaurus, Medical, Encyclopedia.
1. The conversion of atmospheric nitrogen into compounds, such as ammonia, by natural agencies or various industrial processes.
2. The conversion by certain soil microorganisms, such as rhizobia, of atmospheric nitrogen into compounds that plants and other organisms can assimilate.
ni′tro·gen-fix′er (-fĭk′sər) n.
1. (Biology) the conversion of atmospheric nitrogen into nitrogen compounds by certain bacteria, such as Rhizobium in the root nodules of legumes
2. (Chemistry) a process, such as the Haber process, in which atmospheric nitrogen is converted into a nitrogen compound, used esp for the manufacture of fertilizer
1. any process of combining atmospheric nitrogen with other elements, as used in the preparation of fertilizers and industrial products.
2. this process as performed by bacteria found in the nodules of leguminous plants, thereby making nitrogenous compounds available to the host plants.
The process by which free nitrogen from the air is combined with other elements to form organic compounds that plants can use as nutrients. Cyanobacteria and certain other forms of bacteria, especially those that live in the roots of legumes, convert gaseous nitrogen into organic compounds.
The conversion of nitrogen gas to nitrates by some bacteria.