Quantitative comparison of semi- and fully-distributed hydrologic models in simulating flood hydrographs on a mountain watershed in southwest China

To investigate the performance of fully- and semi-distributed hydrologic models in simulating the process of transformation from rainfall to runoff in mountain areas, the fully-distributed models Basin Pollution Calculation Center (BPCC) and HEC-HMS are calibrated for the Zhenjiangguan watershed located in the upper stream of Minjiang River Southwest China using stream-flow observations at the basin outlet. Semi-automatical optimization method is implemented to both models to improve simulated results by removing artificial errors. Based on the consistency of the simulated hydrographs with the observed ones, the statistical coefficients such as the relative error, the probability distribution and the correlation coefficient, are further introduced to evaluate quantitatively the performance of the two models. Analyses indicate that the hydrographs simulated by the BPCC are relatively closer to the observed ones than those simulated by the HEC-HMS in view of the spatial heterogeneity in terrain, soil texture, land cover and meteorological conditions in mountain areas.