中文摘要：

限于目前的资料和技术方法,难以给出具有严格生态意义的生态流量过程,对金沙江下游梯级水库的生态调度,考察了最小月平均流量法、7Q10法、Tennant法、规划最小下泄流量等几种常规的生态流量设计方案,以此作为水库下泄的生态约束,并建立梯级水库联合调度优化模型。以金沙江下游梯级为实例,对比分析了不同生态流量约束、不同水库调度方式的调度运行结果。在此基础上,从生态与发电的制约关系、生态流量约束与水文变化度的关系、生态流量设置的合理性标准等方面进行了分析讨论。研究结果表明：（1）考虑常规生态流量约束的生态调度并没有显著降低梯级水库的发电量,总发电量较不考虑生态调度最大降低约2.4%;（2）生态流量约束有利于降低水库调度引起的水文变化度,对比4种生态流量约束方案,从生态角度Tennant法最优,从发电角度规划最小下泄方案最优;（3）对生态调度,仅从下限的角度满足常规生态流量存在局限性,应尽量利用已有的生态信息,强化生态流量设计的生态基础和生态相关性,提高生态调度的目标性和针对性。研究结论将为未来金沙江下游梯级水库的生态调度提供一定的参考。

英文摘要：

A description of ecological flow is a challenge with the current data and methodology available, so several regular environmental flow alternatives, such as minimum monthly flow, 7Q10, Tennant and Planned minimum release, had to be adopted in optimization of the joint operation of cascade dams in the lower Jinsha. Taking these alternatives as the ecological constraints on the reservoir release, an optimal joint operation model was developed in this study. The optimization results under various environmental flow constraints and various operation modes are analyzed and discussed in this paper. And based on them, some issues are further addressed, such as the bound relationship between ecology and hydropower generation, the inner relationship between ecological constraints and hydrological alteration, and the design criteria of environmental flow. The followings are concluded. （ 1 ） Ecological regulation under regular e~avironmental flow constraints only reduces hydropower outputs slightly by no more than 2.4% in comparison with normal regulation; （2） Environmental flow constraints help lower the hydrological alteration induced by hydropower dams, and in term of ecology Tennant is the best among the four ecological flow alternatives; （3） There is a limitation in ecological flow designs that consider the lower bound only, and it is necessary to stress the ecological foundation and the ecological relevance in the selection of ecological flow alternatives. The study would lend a technical support to ecological regulation of cascade dams in the future.