Lime-nitrogen application reduces N2O emission from a vegetable field with imperfectly-drained sandy clay-loam soil

Abstract We studied the effect of lime-nitrogen (calcium cyanamide, CaCN2) application on the emission of nitrous oxide (N2O) from a vegetable field with imperfectly-drained sandy clay-loam soil. Lime-nitrogen acts as both a pesticide and a fertilizer. During the decomposition of lime-nitrogen in the soil, dicyandiamide (DCD), a nitrification inhibitor, is formed, and as a result lime-nitrogen application may mitigate N2O emission from the soil. The study design consisted of three different nitrogen-application treatments in field plots with a randomized block design. The nitrogen application treatments were: CF (chemical fertilizer), LN (all nitrogen fertilizer applied as lime-nitrogen), and CFD (chemical fertilizer containing DCD). Soil nitrification activity was lower in the LN and CFD plots than in the CF plots, and nitrification was inhibited for a longer period in the LN plots than in the CFD plots. In the LN plots, N2O emission was lower than those of other treatments from 20 to 40 days after ferti...