普者黑岩溶湖滨湿地磷的垂向迁移转化及动态模拟研究

Because of the Karst geomorphologic characteristics, the theory of Karst lake pollution prevention has been recognized more comprehensively. The need for reducing anthropogenic nutrient inputs, especially phosphorus, to aquatic ecosystems to restore aquatic ecosystem health has therefore been widely evidenced. Lakeshore-wetland is viewed as an important component of pollutants reduction and lake ecological restoration. As phosphorus has been scientifically studied to trickle lake eutrophication factor, lots of researchers believe the phosphorus retention effect is currently a hot research topic around world. However, there are three challenges need urgently to be solved when systematically measuring the phosphorus retention effect, including 1. the hydrological variability of the lakeshore-wetland; 2. identification of the key process of phosphorus vertical transporting trend among the surface water, sediment and lithosphere from top to bottom in the lakeshore-wetland and its driving factors; and 3. appropriately dynamic simulation method of phosphorus vertical transporting. Phuzhehei lakeshore-wetland locates at Qiubei County, Wenshan Yunnan Province,where is one of six typical Karst regions in China and is a traditional folded strata belt with Karst peak clusters and depressions. With the unique Karst geomorphological features, Puzhehei wetland has tremendous value for protection, it therefore taken as a case study in this project. Temporal and spatial variability of phosphorus vertical transporting, retention effect and driving factors identification will be systematically revealed based on the field investigation and monitoring, lab simulating experiments, isotopic tracer and in situ test. Two key physic-chemical processes in the lakeshore-wetland will be focused, including 1. phosphorus vertical transporting in water, sediment and lithosphere and driving factors; and 2. effect of phosphorus vertical transporting by groundwater and surface water interaction. The key process of lakeshore-wetland phosphorus vertical transporting and retention effect, driving factors and dynamic sediment-lithosphere source and sink mechanism will also be identified. In order to realize dynamic simulation for phosphorus vertical transporting and retention effect, the main parameters of phosphorus transporting model between water-sediment and sediment-lithosphere will be revised, based on the SWAT model. With the accomplishment of this estimated research, the following conclusion will be achieved: 1. the phosphorus vertical transporting mechanism of Karst lakeshore-wetland will be clear, 2. its driving factors will be identified; 3. the revised SWAT model will be accurately applied for phosphorus vertical transporting processes prediction. It is believed that the findings and the approach proposed in this study will provide more interesting and useful hints to support effective lakeshore-wetland management and designing.

岩溶湖泊特殊地貌特征使其污染防治更为复杂，湖滨湿地是湖泊生态修复的重要组分，对磷的迁移转化研究是目前国内外的热点；但有两方面的难题亟待破解：磷在湿地水-底泥-岩石的垂向迁移关键过程及驱动因子识别；适宜磷的垂向迁移过程动态模拟方法。本项目以滇东南岩溶地貌普者黑湖滨湿地为典型对象，基于现场监测、室内模拟、同位素示踪及原位试验，揭示湿地的水位变异性及其磷的垂向迁移时空分异性的影响；重点研究磷在水-底质-岩石的垂向迁移过程、地表水-地下水交互作用对磷迁移影响的2个关键过程，识别湿地磷的垂向迁移关键过程、驱动因子及底质和岩石的"源-汇"动力学机制；基于SWAT模型，在选择SWAT模型并确定相关模块的基础上，修正磷在水-底质-岩石的垂向迁移模型参数，实现磷的垂向迁移动态模拟。本项目旨在通过典型研究，探索岩溶湖滨湿地磷的垂向迁移关键过程与驱动因素作用机制，为制定科学的岩溶湖滨湿地管理与设计对策提供支持。

岩溶湖滨湿地因底质富钙的特殊环境成为研究热点，因其特殊地貌特征使污染防治更为复杂，湖滨湿地是湖泊生态修复的重要组分，对磷的迁移转化研究是目前国内外的热点。本项目以滇东南岩溶地貌普者黑湖滨湿地为典型对象，在湖滨湿地时空变化特征及生态敏感性的基础上，基于现场监测、室内模拟、及原位试验，揭示湿地的水位变异性及其磷的垂向迁移时空分异性的影响，研究磷在水-底质-湿地植物的垂向迁移过程、地表水-地下水交互作用对磷迁移影响的2个关键过程，重点识别了普者黑岩溶湖滨湿地磷在水-底泥-岩石的垂向迁移转化过程及驱动因子，提出了基于SWAT 模型下的岩溶湖滨湿地磷的垂向迁移转化过程动态模拟，修正了磷在水-底质-湿地植物迁移模型参数，实现l磷的垂向迁移动态模拟。研究成果可为岩溶湖滨湿地生态恢复与群落优化配置以及合理制定岩溶地区湖泊富营养化污染控制方案提供理论指导与技术支撑，为我国其他岩溶地区湖滨湿地恢复与保护推广以及制定科学的岩溶湖滨湿地管理与设计对策提供支持。项目公开发表论文30篇，培养硕士研究生6名，出版专著3部，培养高层次人才2人次，项目参与者职称晋升2人。