NitroScape: a model to integrate nitrogen transfers and transformations in rural landscapes

Modelling nitrogen transfer and transformation at the landscape scale is relevant to estimate the
mobility of the reactive forms of nitrogen (Nr) and the associated threats to the environment. Here we
describe the development of a spatially and temporally explicit model to integrate Nr transfer and
transformation at the landscape scale. The model couples four existing models, to simulate atmospheric,
farm, agro-ecosystem and hydrological Nr fluxes and transformations within a landscape. Simulations
were carried out on a theoretical landscape consisting of pig-crop farms interspersed with unmanaged
ecosystems. Simulation results illustrated the effect of spatial interactions between landscape elements
on Nr fluxes and losses to the environment. More than 10% of the total N2O emissions were due to
indirect emissions. The nitrogen budgets and transformations of the unmanaged ecosystems varied
considerably, depending on their location within the landscape. The model represents a new tool for
assessing the effect of changes in landscape structure on Nr fluxes.