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从长期来看 ,在治理度达到 70 %条件下与治理前相比泥沙输移比减小 50 %左右 ,治理的效益是十分显著的。在治理的过程中 ,与治理前相比泥沙输移比变幅明显减小 ,但在短期内由于暴雨洪水侵蚀力大于工程设计标准而发生毁、垮坝或淤平后 ,仍可以将前期滞留的泥沙重新搬运而出现泥沙输移比大于 1的情况。在黄土高原地区治理前后流域系统次暴雨泥沙输移比均可用径流深度比来定量计算获得 ,泥沙输移比变化的动力机制可用径流深度增与减时水流剪切力的变化来解释
In the long run, when the degree of control reaches 70%, the sediment transport ratio will be reduced by 50% compared with that before the treatment, and the benefit of the treatment will be very significant. In the process of governance, compared with the pre-treatment sediment transport than the change significantly reduced, but in the short term due to storm flood erosive force greater than the engineering design standards were destroyed, collapse or siltation, can still be the pre- Remaining sediment is transported again and sediment transfer ratio is greater than 1. Before and after the management in the Loess Plateau, the sediment transport ratio of sub-heavy rainstorm can be calculated quantitatively with runoff depth ratio. The dynamic mechanism of the sediment transport ratio can be explained by the change of runoff depth and time-dependent shear force