Predicting nitrogen dynamics in a dairy farming catchment using systems synthesis modelling

► Environmental fluxes of nitrogen were estimated for a pasture based dairy farming catchment. ► Typical farming systems were developed based on the results of a catchment survey. ► Dairy farming systems were modelled to investigate the N losses and production. ► Variability between systems and between years was highlighted. ► The environmental and productive implications of current and future farming systems were explored at the catchment level.