Parameterization and multi-criteria calibration of a distributed storm flow model applied to a Mediterranean agricultural catchment
Résumé
The principal challenge in the parameterization of storm flow models for agricultural catchments with an artificial drainage network and fields with different degrees of tillage lies in the parsimonious definition of distributed model parameters in a way that reduces the number of calibration parameters to a justifiable minimum. This paper presents a comprehensive case study for the parameter estimation of a distributed storm flow model applied to an agricultural catchment (0.91km2) in the Mediterranean region. Model parameterization was combined with procedures for multi-criteria, multi-storm calibration, where we automatically calibrated three parameters related to flow velocity and infiltration, and compared single and multi-storm criteria that are based on discharge volume, peak flow, and the NashSutcliffe coefficient. Multi-storm calibration yielded a set of parameter values for the simulation batch with best multi-storm overall performance, which are close to the median values in the pre-calibration of individual storms. Our results suggest that flow velocities and proportionality of the channel infiltration rate do not vary significantly over the course of 11years.