Saturation-excess overland flow in the European loess belt: An underestimated process?

A major challenge in runoff and soil erosion modelling is the adequate representation of most relevant processes models while avoiding over parameterization. In European loess belt, progressive crusting during rainfall events, resulting infiltration-excess runoff, usually considered dominant process generating on catchments covered with silty soils. Saturation-excess may also occur affect their behavior. However, saturation-excess occurrence quantification have rarely been performed not taken into account when these environments. Accordingly, a continuous simulation Austreberthe catchment (214 km2), located belt (Normandy, France), was conducted new Water Sediment (WaterSed) model 12 years, corresponding to more than 780 individual at 25 m spatial resolution. The inter-annual variability closely linked number intense events per year distribution through year. properly calibrated representative set 35 considering either and/or runoff. It able reproduce measured volume for monitoring period. three years were adequately modelled only including An analysis seasonal scale revealed that saturation almost all period, suggesting importance this often overlooked current attempts.