洪泛平原含水层中铁锰胶体动态转化及其对磷迁移转化的控制机理

洪泛平原是中国乃至世界最重要的生态系统之一，其地下水日趋严重的磷污染和周边水体富营养化，威胁着流域的饮水安全和水生态健康。铁锰胶体动态转化是控制磷迁移转化的重要因素，而复杂的地下水系统时空分布与动态演变对铁锰胶体环境行为和磷迁移转化具有显著的影响，因此开展含水层中铁锰胶体动态转化及其对磷迁移转化控制机理研究对保障流域饮水安全和水生态健康具有重要意义。本项目拟以江汉平原地下水监测场为研究对象，通过野外系统监测与室内原位模拟实验，充分利用DGT原位监测、超滤分级、树脂交换、化学连续抽提、胶体表征、光谱检测等技术，系统研究地下水中铁锰胶体与磷的时空分布规律和磷迁移转化的铁锰胶体效应及微观机制，揭示含水层中多过程耦合作用下铁锰胶体动态转化机制和铁锰胶体动态转化与磷迁移转化的协同作用模式，阐明铁锰胶体动态转化对磷迁移转化的控制机理，为地下水中磷循环提供新认知，为水体富营养化的修复和管理提供科学依据。

Floodplain is one of the most important ecosystems in China and even in the world. It is suffering the increasing phosphorus pollution in groundwater surrounded by eutrophic water bodies, which threaten the safety of drinking water and aquatic ecological health in the basin. The dynamic transformations of iron or manganese colloids play important roles on the migration and transformation of phosphorus. However, the environmental behaviors of the iron or manganese colloids itself and the migration and transformation of phosphorus in aquifers depend on the spatial and temporal distribution of complex groundwater systems and its vibrant evolution. Therefore, it is significant to study the dynamic transformations of iron or manganese colloids and its control mechanisms on the migration and transformation of phosphorus in groundwater, to ensure the safety of drinking water and aquatic ecological health. With the help of field investigations and in-situ simulation experiments, this project intends to take Jianghan Plain as the field site, which will focus on the study on the spatial and temporal distribution characterizations of iron or manganese colloids and phosphorus in groundwater, and the effects of iron or manganese colloids on the migration and transform of phosphorus in aquifers or their micro mechanisms in details. Some technologies will be applied well during the study such as DGT in-situ monitor, tangential flow ultrafiltration, resin exchange, chemical continuous extraction, colloid characterization, spectral detection and so on during field work and in situ lab experiments. The dynamic transformation mechanisms of iron or manganese colloids and the coupling models with the migration and transformation of phosphorus will be revealed, and to understand the control mechanisms of the dynamic transformation of iron or manganese colloid on the migration and transformation of phosphorus during coupling multiple processes in aquifers, which can provide a new cognition for phosphorus cycle in groundwater, and provide a scientific basic for the remediation and management of water eutrophication.