Plants, Nutrients and Australian Soils

Accurate determination of the rate of N-fixation in soil is extremely difficult. However, soil ecologists and agriculturalists can derive an estimate of N-fixation with the acetylene reduction assay, which indirectly meansures the activity of the enzyme nitrogenase.

Nitrogenase is the enzyme complex that converts dinitrogen (N₂) to ammonium (NH₄⁺) in bacteroids. It is also active in converting acetylene (C₂H₂) to ethylene (C₂H₄)

Move the mouse over steps 1 to 4 to see the steps in the method used to estimate the amount of N-fixation in a soil sample.