变化环境下澜沧江流域径流适用性利用协同调控模式研究

With the distinct stereo-climate and complex river channel, the spatial-temporal distributions of water resources in Lancang River Basin are heterogeneous. Furthermore, due to the climate changes and high-density hydropower development, significant variance of runoff process is found in the basin, which results in the fierce water resources utilization competition among stakeholders including water supply, power generation, ecology and so on. For the purpose of revealing the target of coordinated regulation for runoff adaptive utilization in Lancang River Basin under changing environments, extensive and typical investigation was carried to establish the database for the utilization of water resource. Moreover, the method for identifying the variation of total factors is established to quantify the influences of high density cascade hydropower development on the whole watershed runoff process and available water resources, and the forecasting model of multi-dimensional water demand in changing environments is selected to reveal the driving effects of cascade hydropower development and economic and social development to the water demand in and outside the river course，and propose the target of coordinated regulation for runoff adaptive utilization. The target of coordinated regulation for runoff adaptive utilization in Lancang River Basin under intense changing environments is proposed in this study, which can provide a scientific decision and the reference for solving livelihood issues about water supply, power generation, ecological security of Lancang River Basin as well as the issues about the sustainable utilization of water resources of other river systems in the southwest source area.

澜沧江流域立体气候明显、河道形态复杂，水文水资源时空分布极不均匀，加之气候持续变化与高密度水利梯级开发，流域径流过程显著变异，供水-发电-生态等利益主体用水竞争激烈。以揭示变化环境下澜沧江流域径流适应性利用协同调控目标为目的，开展广泛调研与典型勘查，初步构建该流域水资源开发利用数据库；构建变化环境下流域水文水资源全要素变异识别方法，量化高密度水利梯级开发对流域径流全过程的影响；研制变化环境下多维水资源需求预测模型，揭示水利梯级开发与经济社会发展对河道内、外需水的驱动效应，提出径流适应性利用调控目标值。通过本课题研究，提出剧烈变化环境下澜沧江流域径流适应性利用协同调控目标，为解决该流域供水-发电-生态安全等重大民生问题提供科学决策，也为西南河流源区其他水系水资源可持续利用提供借鉴。

本项目围绕高密度梯级开发的生态水文效应科学问题，运用水文学、水动力学、水生态学等多交叉学科理论，以澜沧江为例，研究了梯级开发对澜沧江流域重点河段水文过程、生境过程的影响，得出如下结果：.（1）构建了基于“强度-形态”全要素变异测度方法，识别了干流主要水文站洪水过程变异特征，将中下游洪水过程划分成高胖型大洪水、洪峰偏后型较大洪水、尖瘦长尾型中等洪水、矮胖型小洪水等四类，并研究了密度梯级开发对四种洪水类型洪水全要素指标的影响。.（2）构建了基于CE-QUAL-W2的水动力水质模型，研究了梯级开发的生态水文累积影响，发现梯级水库建成后，库区流量过程趋于均化、水位变幅增大、流速明显变缓、水温垂向分层明显、DO浓度逐渐降低。.（3）基于河流生态—生境系统耦合理论，系统解析了流量、水位、流速、水温等生境变化对河流生态系统的影响，发现流量过程改变导致鱼类繁殖期产卵受阻，库区水位增高导致产卵场大幅淹没，流速过程改变导致库区鱼类重分布，水温累积效应对库区鱼类繁殖产卵不利等结论。.（4）构建了以鱼类优先保护为原则的生物优势物种评估指标，基于广义水文过程理论，提出满足中国结鱼产卵期和成鱼期的底质、流速、水深适宜度曲线；构建了河道内流量增量法（IFIM），提出中国结鱼产卵期适宜生态需水量为3200 m³/s，成鱼期适宜生态需水量为1600 m³/s。.本项目在国内外重要期刊发表论文共15篇（SCI论文10篇），在审5篇，出版论著2部，申请发明专利3项，软件著作权2项；1人晋升为教授；培养研究生14名；20余人次参加学术会议；举办了变化环境下水资源协同调控模式等多场国际研讨会。如期完成各项考核指标。.本项目提出的有关水文要素变异识别方法、梯级开发的生态水文响应识别模型、生态需水预测模型以及指示性物种生态需水量计算方法，可丰富高密度梯级开发的生态水文学研究方法，为该地区水资源可持续利用提供重要实践决策。