Nitrogen fixation limitations

Molybdate, although present in small amounts in soil, is an essential nutrient for nitrogen fixation, specifically in the enzyme nitrogenase. It does not move readily through soil and is therefore considered to be of limited mobility. 

The process of nitrogen fixation is an essential part of the nitrogen cycle on the planet earth(l). It is estimated that greater than 60Z of the N2 that is ultimately converted to NH4+ is done so by the nitrogenase enzyme system. The availability of fixed nitrogen is often the limiting factor in plant growth( ). To... 

To the broader biochemical community the term non-heme iron proteins has frequently suggested a limited group of low-molecular-weight proteins confined to electron transfer between enzymes in a limited number of reactions, such as nitrogen fixation and photosynthesis. ... 

Nitrogen fixation counteracts denitrification losses of N from surface waters and is fundamental to replenishing fixed forms of N in all aquatic ecosystems. It is thought to be the main process responsible for maintaining surplus inorganic N in lakes and streams. It is therefore basic to the concept that primary production in most lakes and streams is limited by phosphorus (72). 

Nitrogen fixation. Conversion of atmospheric nitrogen into a form that can be converted by biochemical reactions to an organic form. This reaction is carried out by a very limited number of microorganisms. 

Haque, J. and S. Jutzi (1984) Nitrogen fixation by forage legumes in SSA Potential and limitations.- ILCA Bulletin 20. 

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