基于DEM的分布式水文模型前处理程序开发及应用

DEVELOPMENT AND APPLICATION OF A PREPROCESSING PROGRAM FOR DISTRIBUTED HYDROLOGICAL MODEL BASED ON DEM

作为水文模型不可或缺的一部分,前处理工作的质量在很大程度上影响着水文模型的模拟效果.为了简化前处理工作步骤,提高执行效率,本文开发了一个能够独立运行并具有可视化界面的水文模型预处理程序.该程序能够对数字高程模型(DEM)数据进行河网提取、子流域划分等工作,其特色在于:基于图论编写了无需填洼的水流方向确定算法;提出了"树叶裁剪法"的子流域划分方法;集成了自下而上的汇流顺序演算算法.将该程序应用于拉萨河流域,取得了较好的效果,为分布式水文模型的开发奠定了基础.

Preprocessing of hydrological model will strongly influence the results of runoff simulation,including several procedures such as flow direction determination,runoff order definition,flow accumulation calculation and drainage network extraction.In order to simplify the work procedure and improve the efficiency of model development,a new preprocessing program was developed,which could work independently with a graphic user interface.Only DEM data were required in this program,and characteristics of the program included the following.A method for flow direction determination without sink filling was intergraded;a new method for watershed partitioning-leaf clipping method was developed;The order of runoff routing could be determined according to a bottom-up method.A case study in the Lhasa River basin was presented.In comparison with traditional method,the results of preprocessing method were more efficient,which would be helpful for the development of distributed hydrological models.