物理性分布式水文模型参数灵敏度分析在Bukuro流域的应用

Application of parameter sensitivity analysis for a physically based distributed hydrological model in the Bukuro river basin

以日本Bukuro流域为例,运用Morris筛选法结合误差评价基准,对自主构建的径流-融雪耦合分布式水文模型中物理参数进行灵敏度分析.结果表明:影响降水-径流过程的土壤参数灵敏度由大至小依次为土壤垂直剖面第一层层厚、横向透水系数、垂向渗透系数、糙率;影响融雪过程的融雪参数灵敏度由大至小依次为容积传输系数、温度修正系数、积雪层表面漫反射因数;土壤垂直剖面第一层参数主要影响径流量的计算值,而土壤第二层参数值会影响模拟结果与观测值之间的时间差.本研究方法可为物理性分布式水文模型构建、验证及其在中小尺度流域应用中的参数率定提供借鉴.

In this research,Morris’screening method and an error calibration are jointly adopted to analyze the parameter sensitivity for an independend-developed distributed hydrological model combined with snowmelt in the Bukuro River Basin in Japan.The results indicate that:1)the order of sensitivity of the soil parameters which impact rainfall-runoff process is the thickness of the first soil layer,coefficient of permeability,coefficient of infiltration velocity,coefficient of roughness;2)the order of sensitivity of the main parameters which impact snowmelt is the bulk transfer coefficient,temperature correction factor,albedo of surface of snow cover layer.Additionally,soil parameters of the first layer in the soil vertical profile mainly impact runoff calculated results,while the soil parameters of the second layer generally result in the time difference between the observed runoff and the simulated result.Methods of this study provide a reference for the researches on model validation and parameter calibration for the development and application of the physically based distributed hydrological model for the small and medium-scale basins.