Sensitivity of the peak flows to the spatial variability of the soil infiltration capacity for different climatic scenarios

The use of distributed rainfall-runoff models in applied hydrology has been widely increased in the latter years. One of the main advantages that these model possess with respect to their lumped-parameters counterpart is the possibility to account for the spatial variability of the local runoff production. However, the application of these models is often limited by the large amount of data required, which are quite difficult to obtain. A possible way out for reducing the data requirements of distributed models is to neglect the spatial variability of the soil infiltration process by lumping the correspondent model parameters at the basin scale. This might be a reasonable assumption if one is interested in modelling those situations where the spatial variability of infiltration is expected to exert a marginal effect on the river discharge. Accordingly, the present study is aimed at verifying the effects of the spatial variability of the soil infiltration parameters on the flood flows modelled by a distributed model, for different climatic scenarios. The analysis is carried out referring to the case study of the Secchia River basin, located in northern Italy. (C) 2003 Elsevier Science Ltd. All rights reserved.