Physically based model of soil erosion and pollutant dynamics at a basin scale

In the paper we describe a conceptual model for evaluating sediment transport and pollutants dynamics (BOD, P and N) at a basin scale. The sediment transport model is physically based; the pollutant dynamics model is based on an integral and simplified form of the complex equations. The model was numerically implemented and applied to four catchments in the Po River Area, with extension ranging from 460 to 2150 km2. The topology is described by DEM with cells of 250x250 m2. The time step is of 24 h. The model was calibrated using data measured in the main streams in the period 1993-1999.