关键词: 径流预报; 目标函数组合; 水文模型; 水资源评估; 嘉陵江流域;

Abstract: In the process of hydrological model parameters calibration, different objective functions and their combinations will lead to different runoff simulation results, which will affect the accuracy of the hydrological forecast of the basin.Therefore, taking the Jialing River Basin in the humid area as the research object and by setting different objective functions and their combination scheme sets, we use multi-objective optimization algorithm(NSGA-II) to optimize their corresponding model parameters, and discuss the effects of different objective functions and their combinations on simulation accuracy of runoff of different magnitude and monthly scale.The results show that under different objective functions and their combinations, the simulations accuracy of calibration periods is better than the validation period.If the objective function that takes charge of agreement degree between the hydrological simulation process and the measured hydrological process is not considered, it will lead to poor model simulation accuracy.At the same time, different objective functions and their combinations will have an important impact on the runoff of different magnitude and monthly runoff.In general, considering the multi-objective function combination could make relative error between simulated value and the measured value smaller, and it is obviously better than the single objective.The research results can provide reference for hydrological forecast.

Key words: runoff forecast; objective function combination; hydrological model; water resources assessment; Jialing River Basin;