Use of urease and nitrification inhibitors to reduce gaseous nitrogen emissions from fertilizers containing ammonium nitrate and urea

摘要

Nitrogen (N) fertilizers increase agricultural yields, but also lead to the release of the greenhouse gases nitrous oxide (Nsub2/subO) and ammonia (NHsub3/sub). This not only reduces the efficiency of N use, but also results in climate change and loss of biodiversity. The use of nitrification inhibitors may improve the efficiency of N use and reduce the emission of greenhouse gases. We tested three inhibitors (NZONE MAX, Piadin and N -( n -butyl) thiophosphoric triamide (NBPT)) added to two common N fertilizers (urea and urea ammonium nitrate (UAN)) and determined emissions of COsub2/sub, Nsub2/subO and NHsub3/sub to evaluate the effectiveness of these three inhibitors and to improve our understanding of the soil nitrogen cycle. NBPT effectively reduced NHsub3/sub volatilization by 50% (from 3.0?g NHsub3/sub-N msup?2/sup in urea alone to 1.4?g NHsub3/sub-N msup?2/sup in urea?+?NBPT). Piadin decreased Nsub2/subO emissions (from 0.98?g Nsub2/subO-N msup?2/sup in urea alone to 0.15?g Nsub2/subO-N msup?2/sup in urea?+?Piadin and from 0.81?g Nsub2/subO-N msup?2/sup in UAN alone to 0.39?g Nsub2/subO-N msup?2/sup in UAN?+?Piadin) by inhibiting the conversion of NHsub4/subsup+/sup to NOsub3/subsup?/sup. However, although Piadin was found to be an effective nitrification inhibitor, the risk of higher NHsub3/sub emissions (from 3.0?g NHsub3/sub-N msup?2/sup in urea alone to 4.5?g NHsub3/sub-N msup?2/sup in urea?+?Piadin) with the addition of Piadin cannot be neglected in environmental and economical evaluations.