EasyDHM模型参数识别研究

Study on the Parameters Identification of EasyDHM Model

模型参数取值的准确与否直接影响模拟精度的高低,为了提高乌鲁木齐河流域流量模拟精度,根据LH-OAT分析法筛选出对流域流量模拟精度影响较大的参数,利用SCE-UA方法计算出这些参数的最优值,并用1990—2009年实测日资料进行了参数率定及模型验证。结果表明:1土壤田间持水率、河道长度修正系数、径流曲线系数、土壤深度占总土层厚度的比例对流量模拟的影响最为敏感;2模型在率定期和验证期的模拟值与实测值的日相对误差均低于5%,纳什效率系数均超过0.80,相关系数在0.90以上,表明EasyDHM模型在乌鲁木齐河流域流量模拟的精度较高且适应性良好。

The accuracy of model parameters is directly influenced by the accuracy of simulation. In order to improve the accuracy of runoffsimulation in Urumqi River basin, the 15 factors influencing the accuracy of runoff simulation were selected by using LH？OAT method and theoptimal values of these 15 parameters were calculated by using SCE？UA method. The results show that a） the correlation parameters of soil,channel shape parameters and surface runoff parameters show high sensitivity; b） model in the calibration and verification period simulatedvalues and measured on the duty of the relative errors are less than 5% and Nash Sutcliffe coefficient are more than 0.80 and the correlationcoefficient is greater than 0.90. It shows that EasyDHM model in simulation of Urumqi River basin is of high accuracy and good adaptability.