基于地貌瞬时单位线的缺资料小流域水文预报

摘要

In order to get higher precision of forecast results,combined with surface unevenness of areal precipitation,the initial probability was made an appropriate adjustments. At the same time,considering a certain degree of lag time compared overland flow concentration and subsurface flow concentration with channel flow concentration,the slope as a special river was introduced to geomorphological instantaneous unit,maintaining the computational structural consistency of geomorphological instantaneous unit. The application results show that the aver-age error of improved geomorphologic instantaneous unit hydrograph is 6. 02%,which is better than un-improved geomorphologic instanta-neous unit hydrograph with average error of 14. 70%.%为使水文预报结果具有更高的精度，在地貌瞬时单位线通用公式的基础上，将面雨量的不均匀性反映到面积率上，从而对初始概率作了适当的调整。另外，考虑坡面汇流相对于河道汇流具有一定程度的滞时，将坡地作为特殊的河流引入地貌瞬时单位线，保持了地貌瞬时单位线计算结构的一致性。应用结果表明：改进的地貌瞬时单位线的平均误差为6．02％，而未改进的地貌瞬时单位线的误差为14．70％。