On the criteria for comparing the ability of compounds for retardation of nitrification in soil

Summary

Evidence has been presented to show that the effectiveness of compounds as nitrification inhibitors is better compared using the criterion of percent inhibition of nitrification, when the soil samples not treated with the nitrification inhibitors do not contain any significant amounts of ammonium nitrogen. The criterion based on nitrification rates of soil samples with and without nitrification inhibitor treatments has been proposed for comparing the ability of the compounds in retarding nitrification when the incubated soil samples contain significant amounts of ammoniumnitrogen. Examples have been cited in support of the proposed criterion.