流域水文过程变化机理与工程安全

The Yangtze River basin is chosen as the study domain of the project. The project focuses on the national great demand of evolution of watershed hydrological process and engineering safety of large-scale hydraulic projects under the background of changing environment. It aims to reveal the transformation mechanism of the elements in the hydrological cycle and the climatic driving mechanism behind the hydrological evolution. We will use a coupling method of multiple processes to establish a distributed land-atmosphere-hydrology coupling model of the Yangtze River. Focused on the science issue about the response of large-scale hydraulic projects’ performance to climate change, it is going to find out the dynamic variation rules of engineering service, accompanied with its driving mechanism. We also try to establish a theory and method to guarantee service security of large-scale hydraulic projects scientifically. Moreover, the project is trying to establish a corresponding evaluation system focused on the flow & sediment process, riverbed evolution mechanism and its impacts on engineering safety in the Yangtze River basin. Furthermore, we are researching the changing mechanism under dual influence from natural and artificial function. Quantifying the ecological effects resulting from climate change and human activities,besides, exploring the mechanisms of engineering security, the erosion and deposition in the downstream, flow and sediment flux and saltwater intrusion are targets of the project. In the view of the results, the project is capable of improving the scientific and technological level of flood control and drought relief, security of water resources, in addition, the protection of ecological environment of the whole Yangtze River Basin. It is effective to guarantee the stability of the economic and social development of the basin. Moreover, it is practical and of great significance.

本项目以长江流域为研究对象，针对变化条件下流域水文过程演变与水利工程安全这一重大国家需求，研究水循环要素间的转化机理及其演变的气候驱动机制，提出水循环多过程耦合方法，构建长江流域分布式陆-气-水文耦合模型。研究变化条件对大型水利枢纽工程服役性态影响机制这一核心科学问题，揭示变化条件下工程服役性态演化规律与驱动机理，科学构建大型水利枢纽工程安全服役保障理论和方法；从系统论的角度揭示长江流域累积影响下的河流水沙过程、河床演变机理及其对工程安全的影响，构建相应的评估体系，研究自然和人类活动双重作用下的区域水循环变化机理，定量刻画气候变化和人类活动的影响及其生态效应，探明流域工程安全机制、下游河床冲淤变化机理、水沙通量变化与咸潮入侵机制。可以有效提高长江流域的防洪抗旱、水资源安全、生态环境保护科技水平，保障流域经济社会的安全稳定，可行性强，意义重大。

本项目通过长江流域实验平台，进行了气候变化环境下流域水文基本规律的实证研究，阐明了水循环要素间的转化机理及其演变的气候驱动机制，量化了多形态和多源“水”之间的补给关系，创新了流域水循环基础理论，发展了水循环要素时空多尺度转换与参数化方案，提出了水循环多过程耦合方法，构建了长江流域分布式陆-气-水文耦合模型，研究了变化条件下水文水资源演变规律和可持续性。综合考虑了荷载因素、多重环境因素等变化条件下，从大型水利枢纽工程局部结构损伤与整体服役性态劣化的角度，研究了大型水利枢纽工程服役性态演化规律，分析了大型水利枢纽工程服役性态的驱动规律，建立了多因素变化条件下大型水利枢纽工程服役性态演化模型，揭示了大型水利枢纽工程结构破坏与灾变机理。探讨了水沙过程变化与河流演变的关系以及涉河工程群与水沙过程变化的关系，揭示了涉河工程群引起的河流系统水沙过程变异机理。构建了非稳态咸潮入侵解析模型，得到河口地区盐水在时空上的分布变化表达式，结合数学模型，确定了解析模型的主要参数，分析了盐度变化与水位、流速变化规律异同性，探讨了不同时间尺度下盐水入侵的时空变化规律和特征，研究了河口复杂地形及特殊动力因子的响应关系，模拟了不同动力格局对多汊道河口咸潮入侵的影响过程，分析了咸潮上溯对河口通量变化的响应程度。在本项目的支持下，发表学术论文162篇，其中SCI论文107篇，授权发明专利6项。获得国家级科技进步二等奖1项，国家级技术发明二等奖1项，省部级科技进步奖一等奖2项。培养了博士研究生9名，硕士研究生66名。创新人才推进计划中青年科技创新领军人才1项，国家“万人计划”科技创新领军人才1项，江苏省“创新团队计划”1项，江苏省“333工程”第二层次培养对象人选2人。