Assessment of Nitrogen Fixation in Terrestrial Environments in Field Conditions

THE knowledge that the nitrogen-fixing enzyme complex, nitrogenase, catalyses various reductions as well as the formation of ammonia from dinitrogen 1,2 has made possible an assay based on the reduction of acetylene to ethylene which is detected by gas chromatography with a hydrogen flame ionization detector 3–6 . The equipment required is compact enough to be carried in a mobile laboratory, which has not previously been easy using 15 N 2 as a tracer.