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.

这样既可以较精确地反映出河道附近格网的，可以让各个子域内的汇不会跨越子域的分岭。

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.

岩溶斜坡岩溶洼地为地表汇集区及地下排泄区，岩溶作用相对较弱，储层不发育。