健康的流域生态系统是保障经济社会可持续发展的基础，也是国家“十四五”规划的重要目标，生态调度是生态恢复和保护最为有效的措施之一。随着复杂人类活动行为对流域自然水文过程产生了扰动，而流域生态系统的健康受水循环及其伴生的生态过程影响，如何统筹协调水利工程与社会经济发展、生态文明建设之间的矛盾，实现流域生态恢复的“自然化”目标，是近年来生态调度的研究热点和难点问题。本文从基于水文要素的“自然化”生态需求、考虑参数不确定性的基流概率描述、流域生态水文情势变化的成因分析展开了深入研究，从而为复杂水资源系统中面向生态的水库群适应性调控策略研究提供了新的思路。 论文以汉江流域为研究对象，首先基于水文改变指标体系和相似年敏感分析方法，确定出6个生态最相关水文指标，并运用多种变异诊断方法识别出流域生态水文的“真正”变异点和稳定时段，揭示了汉江流域生态水文情势的演变规律，提出了基于稳定径流序列及生态最相关水文指标的“自然化”生态目标计算方法。其次，针对传统确定性模型分割的基流难以刻画水文过程的不确定性，将数字滤波法与最严格基流点筛选准则相结合，采用GEV极值分布作为滤波参数和基流指数最大值的边缘分布、Frank-Copula函数作为双参数的联合分布，获得了具有物理意义的基流及其概率描述。然后，建立了考虑水库和取用水影响的多源数据驱动的分布式水文模型WetSpa，定量识别了影响流域生态水文情势变化的气候变化、水利工程调蓄、取用水等驱动因子的贡献率，结果表明水库调蓄是影响汉江流域生态水文情势变异的主要驱动因子，其次是取用水；并结合CMIP6气候模式数据预测了流域未来（2021-2060）径流呈增加趋势。最后，根据辨识出的影响断面生态目标的主要驱动因子，构建了面向生态的水库群多目标优化调度模型；并将基流的概率描述作为模型输入，针对现状年、中期和远期情景选取三个极端方案，计算了“自然化”生态保护目标满足程度，分析了基于重点水利工程调控手段的联合调控策略。 本文研究了流域生态水文情势的变异规律及其驱动机制，提出了面向生态的水库群适应性调控策略，研究结果对于维系河流生态系统健康稳定、发展流域生态调度理论和方法具有重要的理论意义。同时，对于解决水资源综合利用过程中的关键问题具有重要应用价值，研究成果可为其他流域系统开展生态调度所借鉴。
A healthy basin ecosystem is the basis for the sustainable development of economy and society, as well as an important goal of the national 14th Five-Year Plan. Ecological regulation is one of the most effective measures for ecological restoration and protection. As complex human activities have disturbances on basin natural hydrological processes, and a healthy ecosystem of the basin is affected by water cycle and its associated ecological processes. How to coordinate the contradictions between water conservancy projects, social-economic development and ecological civilization construction, and to achieve the naturalization target of basin ecological restoration, has become a hot and difficult issue in recent years.This paper studied the naturalization ecological needs based on hydrological factors, the probability deistribution of baseflow with parameter uncertainties, and the driving mechanism of the basin eco-hydrological regime changes, so as to provide new research ideas for ecological regulation model of reservoir groups in complex water resources system. Taking the Han River Basin as the research area, the paper firstly determined 6 the most ecologically relevant hydrological indicators （ERHIs） based on IHA system and the similar-year sensitivity analysis method. Then a variety of variation diagnosis methods was used to identify the true variation points of the eco-hydrological regeim in Han River Basin. Further, an ecological objective calculation method that can reflect the naturalization target of basin ecological restoration was proposed based on stable runoff series. Secondly, as the uncertainty of hydrological process is difficult to be described by the traditional baseflow segmentation method using deterministic model, the digital filter method was combined with the selection criteria of strict baseflow point to analyze the uncertainty of filter parameter and baseflow index. When using GEV extreme distribution as the edge distribution and Frank-Copula function as the joint distribution of two parameters, the physical baseflow and its probabilistic description were obtained. Thirdly, a multi-source data driven distributed hydrological model （WetSpa） was established that considered the impact of human activities. Then the contribution rates of driving factors such as climate, reserviors and water withdrawals that affected the changes of eco-hydrological regimes were quantitatively identified through model simulation. The results showed that reservoir operation was the main driving factor affecting Han River Basin, followed by water withdrawal. Combined with the CMIP6 climate data, the change trend of the future runoff of the basin was predicted. Fourthly, an ecologically-oriented multi-objective scheduling model of reservoir groups was constructed according to the identified main driving factors. The probability description of baseflow was used as the model input, and three extreme scenarios were selected for the current year, medium and long term scenarios to calculate the satisfaction degree of the naturalization ecological targets. finally, a set of ecological regulation and control strategies based on the identified key reservoirs was put forward. This paper studied the variation law and driving mechanism of the eco- hydrological regiem of the Han River Basin, and proposed an ecologically-oriented scheduling model for reservoir groups. The results have important theoretical significance for maintaining the health and stability of river ecosystems, and developing the theory and method of basin ecological regulation. At the same time, the study has important application values for solving ecological problems in the water utilization process, and can be used as references for other basins to carry out ecological regulation.
