基于三维参数化方案的二元分布式水文模拟

Dualistic Distributed Hydrological Simulation under 3D Parametric Scheme

分布式水文模型通过参数化方案处理参数空间异质性对水文模拟的影响。针对目前参数化方案对山区流域参数垂向差异考虑不足的问题,开展了三维参数化方案研究,建立了基于垂直地带性的三维参数化方案,针对性地改进了WEP-L模型,并以密云水库上游流域为例对方案效果进行了分析。结果表明:(1)和以往二维参数化方案相比,三维参数化方案可大幅提升分布式水文模拟精度,流域内主要控制站近60年逐月实测径流过程模拟效果得到有效改善;(2)模拟精度提高的主要原因是改进后方案同时考虑了植被类型垂直地带性及海拔高度对参数空间分布的影响。

Distributed hydrological model deals with the influence of spatial heterogeneity of parameters on hydrologic simulation through parameterization scheme.Aiming at the problem that the current parameterization scheme does not consider the vertical dif⁃ference of parameters in mountainous watershed,a three-dimensional(3D)parameterization which based on vertical zonality was es⁃tablished,and the WEP-L model was improved correspondingly.Taking the upstream of Miyun Reservoir as an example,the ef⁃fect of the scheme was analyzed.The results show that the 3D parameterization scheme can greatly improve the accuracy of distrib⁃uted hydrological simulation,and the simulation effect of monthly measured runoff process has been effectively improved at main control stations in recent 60 years.The main reason for the improvement of the simulation accuracy is that the vertical zonality of vegetation types and the influence of altitude on the spatial distribution of parameters are considered in the improved scheme.