引黄灌区泥沙远距离分散配置模式及其评价指标

Long-distance and distributed mode of sediment deployment in irrigation systems of Lower Yellow River and its evaluation indexes

通过分析引黄灌区各类泥沙处理方式,本文提出了引黄灌区泥沙远距离分散配置模式并论述了其内涵。指出该模式是灌区水沙联合优化配置的一种形式。给出了远距离输沙系数、泥沙分散系数的概念和计算方法。利用配置模式的评价指标对引黄灌区的泥沙分布状况进行了评价。结果表明河南引黄灌区的远距离输沙系数和分散系数都大于山东省灌区,浑水灌溉方式的远距离输沙和分散程度大于集中处理泥沙方式。在引黄灌区内,提高渠道输沙能力是实现泥沙远距离分散配置模式的重要前提;对于渠道输沙能力较小的引黄灌区,渠首宜采用集中处理泥沙的方式处理粒径大于0.05mm的有害泥沙;对于渠道输沙能力较大的灌区,可直接采用分散处理泥沙方式。

A sediment treatment mode, namely long-distance and distributed deployment mode, is suggested based on the investigation on current management technologies of typical irrigation systems in the Lower Yellow River. The concept of this technology is presented. It optimizes the combined deployment of water and sediment in irrigation systems. The indexes for evaluating the effectiveness of this sediment treatment mode including the coefficient of long distance sediment transportation and coefficient of sediment distribution are proposed. The application of this evaluation system to the typical irrigation districts in the Shandong Province and Henan Province shows that for realizing long-distance and distributed deployment of sediment, sediment detention basins should be established at the entrance of irrigation systems to get rid of the coarse sediments with diameter larger than 0.05mm and at the same time the sediment transport capacity of irrigation cannels must be improved to enhance the transportation of sediment.