考虑湖泊范围的子流域划分和编码方法研究

Study on Sub⁃Watershed Division and Coding Method Considering Lake Extent

现有子流域划分方法一般通过虚拟河网将湖泊划分为若干部分,每个部分分属不同的子流域,并未考虑湖泊范围的完整性和独立性,不利于湖泊水量平衡分析。为解决这一问题,提出一种考虑湖泊范围的子流域划分和编码方法,包括湖区子流域(湖泊子流域和湖滨带子流域)划分和非湖区子流域划分方法,以及根据栅格流向和河道汇流关系,确定子流域间的上下游拓扑关系并生成其拓扑关系表。黄河源区(唐乃亥以上区域)有鄂陵湖和扎陵湖两大湖泊,采用该方法对黄河源区进行子流域划分和编码,并基于流域分布式水文模型(WEP-L模型)进行模拟验证,结果表明该方法可实现研究区湖泊区域的自动识别、子流域划分及编码,水文模拟结果和湖泊水量平衡计算结果合理。

The existing sub⁃watershed division method generally divides the lake into several parts through a virtual river network,each part belongs to a different sub⁃watershed,which does not consider the integrity and independence of the lake range,which is not conducive to the analysis of lake water balance.In order to solve this issue,a sub⁃watershed division and coding method considering lake extent was proposed,including lake basin(lake basin and lakeside zone basin)division and non⁃lake basin division method,and determining the upstream and downstream topological relationships between sub⁃watersheds and generating their topological relationship tables according to the grid flow direction and river channel convergence relationship.The method was used to divide and code the sub⁃watershed of the Yellow River source area(above Tangnaihai),and the simulation verification was carried out based on the distributed hydrological model of the river basin(WEP⁃L model).The results show that the method can realize the automatic identification,sub⁃watershed division and coding of the lake area in the study area,and the hydrological simulation results and the calculation results of lake water balance are reasonable.