The Shiyang River Basin is one of three large continental river basins in Hexi Corridor and is the region facing the greatest pressure on water resources.The utilization efficiency of water resources not only affects sustainable socioeconomic development but also affects the ecological security of the country.The irrigated area is the largest water consumption area in an arid inland river basin and is also a highly controversial multiuse area;therefore,comprehensive watershed management is fundamental in this area.Water-use efficiency has a profound effect on oasis stability and harmonious socioecological and productive developments in such areas.The present study used the DEA model,and we measured the agricultural water efficiency and its influencing factors in 13 irrigated areas of the Shiyang River Basin during 2000-2010.The results showed obvious temporal and spatial differences in water-use efficiency in irrigated areas before and after integrated measures.The water-use efficiency fluctuation noted during the early stages of management became more stable by 2007.The water-use efficiency of the irrigated areas were as follows:W-S irrigated areas in the middle reaches (taking wells and springs as irrigated water sources) ＞R irrigated areas in the middle reaches (taking rivers as irrigated water sources) ＞R-W-S irrigated areas in downstream(taking rivers 、wells and springs as irrigated water sources),reflecting the strong influence of the watershe comprehensive measures.The key control region showed higher water-use efficiency than the non-key areas,but that of the downstream Hongyashan Reservoir Irrigated Area was still very low.The irrigated areas had different degrees of water and land redundancies;The redundancy of water-use in the W-S irrigated areas are more than the R irrigated areas,however,its redundancy and slack variables are decreasing,which indicates that the water resources conservation degree are strengthened after the integrated management.Before integrated management,the redundancy of irrigated land in the W-S irrigated areas and R-W-S irrigated areas were most;after,the redundancy were reduced,reflecting that "closing wells" and "compressing farmland" plays an obvious role.%石羊河流域灌区是人-地-水矛盾高度集结之地,也是流域综合治理的重点地区,其用水效率的高低深刻影响着绿洲的稳定性和三生系统(生产-生活-生态)的和谐发展状态.选择DEA模型,测度了《石羊河流域治理规划》实施前后13个灌区农业用水效率变化.结果表明:综合治理前后各灌区用水效率存在明显的时空差异,以2007年为拐点,总体呈现前期波动下降、后期稳定提升的发展历程.用水效率中游井泉灌区＞中游山水灌区＞下游山水井泉混合灌区,映射出流域治理的强大影响力.重点治理区域高于非重点区域,但下游红崖山水库灌区用水效率仍很低.各灌区水土冗余是影响用水效率的共性因素.水冗余井泉灌区＜山水灌区,但冗余度和松弛变量均在减少,说明水资源节约程度在加强.治理前井泉灌区和混合灌区土冗余最多;治理后山水灌区和下游红崖山水库灌区土地在减少冗余度,说明“关井压田”对井泉灌区起到明显作用.
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