Modeling Nitrogen Oxide Emissions from Current and Alternative Pastures in Costa Rica

摘要: Emissions of nitrogen (N) oxide were simulated for one current, unsustainable pasture management system (Natural) and two alternative, sustainable systems (Grass-Legume Fertilized Improved) relevant to the Northern Atlantic Zone (NAZ) Costa Rica. To produce frequency distributions N emissions, an expert generating technical coefficients pastures was linked with a process-based simulation model. The model generated parameter sets representing different options three systems. rerun each set. Simulated nitrous (N 2 O)-N losses 25 yr after establishment 3 5 kg ha -1 natural pastures, 12 15 grass-legume mixtures, 7 28 fertilized grasses. Losses nitric (NO)-N 1 8 16 Stepwise multiple regression showed that O-N explained by annual C input soil (R = 0.997), NO-N attainable dry matter production 0.972). Carbon controlled stocking rate fertilizer level. Soil-atmosphere emissions from may increase factor when are converted improved pastures. Such conversion sustainability stopping decline N. However, change is not necessarily global perspective because it increases emission greenhouse gases.