C．O．Clark单位线在黄土高原小流域汇水演算中的应用

Application of the C. O. Clark unit hydrography to the flux computation in a small scale basin of the Loess Plateau

通过求解时间-面积曲线和应用线性水库调节建立Clark单位线,对陇西黄土高原典型流域汇 流过程进行演算,并对结果进行分析．结果显示:传统的线性或非线性集总方法在进行流域汇水演算 时具有结构简单、参数少、模型容易实现等优点,但未能考虑空间异质性对水文过程的影响,构成模型 计算误差的主要来源,同时也造成模型中水文学概念模糊以及过程机制的不尽合理．克服上述缺点的 途径之一是将传统方法与现代地学先进技术手段(特别是地理信息系统(GIS))有机结合．

Based on the computation of the time-area map and construction of the linear reservoir, the C. O. Clark unit hydrography was built for the calculation of the flux process in an operational basin of the Loess Plateau. At the end of the paper, an analysis was made of the result derived from the computing. We can reach the conclusion that, although the traditional ways, whether linear or not, were used in accounting the surface flux process with the advantages of a simplified model structure, fewer parameters and being easily present, errors from the model could not be avoided because of its ignoring of the spatial variation in the flux process. At the same time, the model above would make the hydrologic concepts more fuzzy and the model mechanism more illogical. To deal with these problems, the combination of the traditional ways with the GIS （geographic information system） should be done by the hydrological worker to strengthen their ability of controlling the spatial variation during the computation of the flux process in basin scale hydrological simulation.