复杂感潮河网区水系连通格局对水环境影响机制

River and lake system is the most important carrier of water, and the River and Lake System Interconnection(RLSI) is a key measure for water resources protection, function recovery of water ecosystem and improving eco-environment. In previous studies, the concept, classification, feature and effect evaluation of interconnected water system were more concerned. However, there is little research about internal influence mechanism of water system interconnection in response to water environment. The water flow movement which affected by tidal and upstream runoff is extremely complicated. In this study, the simulation model of sluice-pump group control which coupled with water quantity、water quality and water ecology is established. The response mechanism of water flow and substances migration, feedback regulation mechanism of water ecology which is affected by both fluvial and tidal dynamics and sluice-pump group control can be analyzed by the model. Study on the theory for regions and levels of sluice-pump group in tidal river area is carried out, in order to explore the response mechanism of water system interconnection in response to water environment by multi-factors. The findings of the study can provide a new idea and method for study on the water system interconnection theory and hydrodynamic in complicated tidal river area, and are helpful for flood discharge and water environment improvement in Pearl River Delta region. Meanwhile, the research result can be helpful for water ecological environment improvement for the national strategy of Guangdong-Hong Kong-Macao Greater Bay Area.

河湖水系是水的重要载体，河湖水系连通是进行水资源保护、水生态系统功能恢复、改善区域水环境的重要措施之一。以往的水系连通理论研究更多的侧重于连通性的概念、分类、特征及效果评价等方面，而探究水系连通格局对改善水环境功能的内在作用机制的研究并不多见。受潮汐和径流双重作用下的感潮河网区水流运动异常复杂，通过构建耦合水量—水质—水生态的河网区闸泵综合调度模拟模型，解析径潮动力和闸泵群调控复合驱动下的河网区水流、物质运移响应机理和水生态系统反馈调节机制，开展河网区闸泵群分区分级技术研究，以改善水环境为目标探索多源因素作用下的水系连通性响应机制。项目研究成果对于水系连通理论以及复杂感潮河网区水流动力学研究丰富了新的思路和方法。对于珠江三角洲河涌泄洪整治、水资源及水环境改善具有重要的技术支撑作用，同时也为粤港澳大湾区国家战略在生态环境改善方面有巨大的推动作用。

河湖水系连通是进行水资源保护、水生态系统功能回复、改善区域水环境的重要措施之一。本研究通过系统梳理国内外有关河湖水系连通工程建设及理论研究进展，在总结珠三角河网水系特点及问题的基础上，提出珠江三角洲河湖水系连通定义和内涵。针对珠三角河网区水系连通规划重要关键技术——耦合分析模型模拟技术。在对示范区中顺大围开展的模型模拟优选技术的基础上，针对珠三角河网区的一类典型河湖连通问题—河网结构连通性较好，但由于闸泵调度不合理造成水力连通，进而影响水环境质量恶化，提出以改善水质为连通主要目标，通过水闸联合调控为主的连通规划关键技术。. 基于水系连通的三角洲河网区闸泵集群实时调度技术可在对珠江三角洲河网水系进行分区分级的基础上实现感潮河网区闸泵群联合有序调度，增强水系连通性，加快水体交换更新。推荐的调度方案对联围实行控制性引水，可维持外江下泄流量满足抑咸要求，以确保大湾区城市群供水安全。通过珠江三角洲河网区闸泵群联合调度模型与优化调度技术，可使珠三角各片区河网水系水环境改善效果达到最优。故研究成果可作为保障河网区水系连通、改善河网水环境、确保大湾区城市群供水安全的重要技术支撑。. 珠江三角洲河网水系复杂，联围众多。其中，中顺大围是诸多联围中水系结构最复杂、外江闸泵群调控能力最强、联合调度难度最大的最具代表性的联围。本研究以中顺大围作为研究实例对闸泵群优化调度进行了全面深入的研究，其研究方法和研究成果可为其他联围的优化调度提供借鉴和参考。