多闸坝重污染河流水量水质演变及其生态效应量化

Currently, the effect of water projects on hydrology, environment and ecology is a hotspot and frontier difficult issue in the international resources, environment and ecology protection research. Focusing on the severe water related problems of Huai River Basin (viz. the highest intensity of dams and sluices, the serious situation of flooding control and pollution prevention, the continuous deterioration of aquatic ecosystem, etc.), the Youth Foundation has made the fruitful achievements including: (1) have realized the integrated water quantity and quality modeling coupling with the operation rules of dams and sluices; (2) have put forward the new quantitative framework to assess the hydrologic and environmental effects of dams and sluices which set the water system as the research unit at the basin scale; (3) have deeply analyzed the hydrologic effect of dams and sluices in the main water system; (4) have published 5 SCI journal papers, 1 monograph, 2 software copyright registration certificates and the foundation leader promoted to the associate professor successfully, which have far exceeded all the foundation’s objectives. This project was the continuation, sublimation and extension of the framework of Youth Foundation. The main works contain that: (1) hydrologic, environment and aquatic ecology classifications and the variation detection in the high regulated Huai River Basin at the basin scale; (2) analyzing the action mechanism of hydrology and environment elements on aquatic ecology and identifying the key elements; (3) quantifying the ecological effect of dam groups by the comparison of the variations of key elements in the several scenarios; (4) putting forward the research method and theory system of the hydrologic- environmental- ecological effects of dams and sluices. All of these works will be carried out by using the detection of the long historical observed data and the field monitoring. The technical means include statistical detection, cluster analysis, mathematics simulation, scenarios analysis and analogy analysis, and so on. This research will provide a scientific basis and technology support to recognize the function of dams group in basin development and protection, and is of important significance to water resources sustainable utilizing and water pollution improvement in Huai River Basin.

针对淮河流域闸坝众多、防洪防污形势严峻、生态环境持续恶化等问题，青年基金已实现闸坝群运行规则与水文、水质模型之间的耦合；提出了在流域尺度上以水系为单元量化闸坝群水文水环境效应的新思路；深入分析了主要水系闸坝群的水文效应；已发表SCI论文5篇，出版专著1部，获软件著作权2项，负责人成功晋级副研究员，超额完成各项考核指标。本项目是青年基金的延续、升华和扩展。利用历史资料分析和现场监测两种途径，采用统计检测、聚类分析、数值模拟、情景分析、综合评价等多种手段，从流域尺度上开展闸坝调控下水文、环境和水生态聚类和变化特征分析；检测影响水生态的关键要素并探明其作用机理；对比多种情景下关键要素的变化特征，量化闸坝群的生态效应；最终形成淮河流域闸坝群水文-环境-生态效应评价体系与量化方法；为客观认识闸坝在流域开发和保护中的作用提供理论支持，也对淮河流域水资源持续利用和污染防治、生态修复等具有重要指导作用。

本项目属于青年-面上连续资助项目，仍以淮河中上游流域和典型闸坝为研究对象，通过大量野外实验、数值模拟和统计检测等手段，在流域尺度上探明了闸坝调控下水文、水环境等关键生态要素的演变规律，揭示了影响河流生态系统的关键要素和作用机理；量化了主要水系闸坝群的生态效应。关键数据和结果有：（1）收集近四年淮河流域重点断面径流、水质和水生态的第一手观测序列资料，形成较完备的水环境与水生生态监测数据库，为项目的开展提供丰富的基础数据；（2）提出了考虑生物地球化学过程的流域水循环系统模型（HEQM）和水循环多过程多要素均衡率定方法，为闸控流域水量水质演变及其生态效应提供重要的技术支持，结果表明69%的径流指标模拟精度有所提高，而水质的模拟精度提高了20%左右。（3）将闸坝对传统径流总量指标扩展到径流情势多要素综合评估指标体系，并提出区域综合特征识别方法。18/30的站点径流类别受闸坝调控的影响发生了显著改变，北部山区源头站点受影响最大，其次是沙颍河中下游站点，最小是淮河干流以南的站点。（4）从水生生物总体分布来看，昭平台至漯河生物物种较丰富，周口至颍上最丰富，而临淮岗至蚌埠物种较少。在时间上物种多样性指数呈减小趋势，而非汛期多样性指数要高于汛期。（5）从径流情势、水质因子对生态系统的影响贡献来看，在非汛期径流情势对生态系统时空分布的解释度为43.0%，其中最小径流和低流量的影响最大；在汛期总体解释度略有降低，为34.0%，其中最大径流和高流量发生频率的影响最大。在非汛期水质因子的解释度是64.0%，其中TP和TN的贡献率最大；而在汛期的解释度是76.0%，CODCr、叶绿素a和NH4-N的贡献率最大。（6）从闸坝群的生态效应来看，闸坝对上游生态系统健康有正面影响，特别是在汛期；对中游生态系统健康有一定负面影响，但对下游生态系统健康影响并不显著。这一结论与闸坝的径流和水质效应空间分布基本一致。目前成果已发表20篇学术论文，其中SCI/EI11篇，出版专著1部，获软件著作权4项，超额完成各项考核指标。研究为客观认识闸坝在流域开发和保护中的作用提供完备的理论和技术支持，也对淮河流域水资源持续利用和污染防治、生态修复等具有重要指导作用。