Application of the Daycent biogeochemical model to assess GHG emissions from an Swiss grassland.

Grassland systems are one of the main source of greenhouse gases (GHG), particularly nitrous oxide (N2O) and methane (CH4). This makes grassland systems great contributors to global warming. Management practices, soil types and climatic conditions are the main drivers influencing the magnitude of GHG emissions, therefore assessing their interaction is essential in order to identify practices that lead to GHG emission reductions. Biogeochemical process-based models are a powerful tools to overcome known constraints of field experiments, i.e. high costs, limited range of practices, etc.. On this basis, the process based model DAYCENT, widely applied worldwide on grassland sites, has been applied for estimating the emission of the major N trace gases (i.e. N2O, NO flux, etc.) and CH4 considering different management options.