黄河上游水库对宁夏河段防洪防凌及灌溉的影响与对策

黄河上游已建水库特别是龙羊峡、刘家峡、青铜峡３座水库，对宁夏河段的防洪防凌、灌溉有着重要影响。建库后，龙羊峡、刘家峡两水库拦蓄洪水、削减洪峰作用显著；凌期平均封河日期推迟、平均开河日期提前、封冻天数缩短，冰情、冰害有所减轻且主要发生在库区；在一定程度上缓解了宁夏引黄灌区春灌缺水的局面。针对建库后河道冲淤及河势的变化，需加强河道整治和上游水库的调节运用，使水库更好地发挥兴利除弊的作用。

The Effect Of Yellow River Upper Reach Reservoir on Flood Control, Ice Prevention and Irrigation Of Ningxia River Reach and Corresponding Treatments

The existing reservoirs on the upper reaches of the Yellow River, Particularly Longyangxia Liujiaxia, Qingtongxia, have significant effect on flood control, ice Prevention and irrigation of Ningxia river reach. Longyangxia and Liujiaxia reser- voirs play an outstanding role in flood impoundment and flood peak reduction of Ningxia river. The average number of river frozen days has been reduced and the problems associated with ice have been minimized and limited to the reservoir area. Water shortage occured during spring irrigation in Ningxia Yellow River diversion irrigated area is moderatedly eased. To prevent scouring and silltation in the river due to reservoir filling and change of river course, river improvements and adjust- ment of upstream operation have to be strengthened.