Integration and calibration of a conceptual rainfall-runoff model in the framework of a decision support system for river basin management

摘要

Water balance models provide significant input to integrated models that areused to simulate river basin processes. However, one of the primary problemsinvolves the coupling and simultaneous calibration of rainfall-runoff andgroundwater models. This problem manifests itself through circular arguments- the hydrologic model is modified to calculate highly discretizedgroundwater recharge rates as input to the groundwater model which providesmodeled base flow for the flood-routing module of the rainfall-runoff model.A possibility to overcome this problem using a modified version of the HBVModel is presented in this paper. Regionalisation and optimization methodslead to objective and efficient calibration despite large numbers ofparameters. The representation of model parameters by transfer functions ofcatchment characteristics enables consistent parameter estimation. Byestablishing such relationships, models are calibrated for the parameters ofthe transfer functions instead of the model parameters themselves. Simulatedannealing, using weighted Nash-Sutcliffe-coefficients of variable temporalaggregation, assists in efficient parameterisations. The simulations arecompared to observed discharge and groundwater recharge modeled by the StateInstitute for Environmental Protection Baden-Württemberg using the modelTRAIN-GWN.