Emissions of ammonia and nitric oxide from an agricultural site following application of different synthetic fertilizers and manures

摘要

In the present study, ammonia (NH3) and nitric oxide (NO) emissions were measured by the dynamic flux chamber (DFC) method from a cropland of Chinese cabbage over a one and a half month period (September–October, 2006). By applying a combination of three treatment (T) types (comprising different proportions of manure, urea, and NPK fertilizer) to the crop field, the effects of such treatments on emission flux were assessed in relation to the amount and type of fertilizer. The magnitude of NH3 emission (μg m?2 h?1) varied in the following order: T2 (4,067), T1 (2,263) and T3 (738). NO fluxes (μg m?2 h?1) also followed the same descending order of T2 (898) > T1 (477) > T3 (81). The possible effects of soil pH on NH3 fluxes were detected, as they concurrently exhibited a gradual and periodic change during the experimental period. Likewise, temperature was also found to have significant effect on NH3 and NO emission behavior. The results of the present work confirm that the application of fertilizer, when tested in the form of diverse treatment types, affected the emission of NH3 and NO in fertilized field soils at varying degrees.