subdrainage

This method can acurately simulate the flow direction in gird near river, and can keep the direction of waterflow from crossing the watershed of subdrainage area.

这样既可以较反映出河道附近格网的水流方，又可以让各个子流域内的汇流方和水流方不会跨越子流域的分水岭。

The karst depression belongs to the accumulative area of surface water and subdrainage area of subsurface water, the karstification is relatively week, and reservoirs are undeveloped.

斜坡和洼为表水汇集及下水排泄，作用相对较弱，储层不发育。