DDRM模型在乌江流域降雨径流模拟中的应用

Application of the DEM-Based DDRM Model in the Wujiang Basin

以地理信息系统(GIS)为平台,对乌江流域的数字高程模型(DEM)进行处理,提取了乌江流域的河网水系及数字流域信息,构建基于DEM的分布式降雨径流模型(DDRM),利用SCE-UA算法率定模型参数,采用纳什效率系数和径流相对误差对模拟效果进行评定分析,并与新安江模型的模拟结果进行对比。研究发现,在水文资料一致性未被破坏的前提下,DDRM对流域出口日流量过程的模拟效果略优于新安江模型。除了能模拟流域出口处的径流过程,DDRM还能模拟任一时刻土壤含水率及径流量的空间分布,且其结构简单、参数较少,可以在湿润地区推广应用。

Based on the digital elevation model data and the river network extracted using geographic information system, the DEM-based distributed rainfall-runoff model (DDRM) is built for the Wujiang basin and its parameters are calibrated by the SCE-UA optimization algorithm. The simulation performance of DDRM is evaluated by both the Nash-Sutcliffe Efficiency and the relative error of runoff depth and then compared to that of the Xinanjiang model. The results show that on the premise that the consistency of hydrological data is not destroyed, DDRM can achieve a better performance than the Xinanjiang model in simulating the runoff process. In addition to simulating the runoff process at the outlet of the watershed, DDRM can also simulate the spatial distribution within the basin of both the soil moisture and runoff at any time. For its simple structure and parsimonious parameters, DDRM has great application potential in humid basins.