RAPID: Turning a Lake Sinkhole Event into Natural/Man-Made Tracer Experiments and Data Collection Campaign for Advanced Understanding of Karst Hydrogeology and Solute Transport

尽管岩溶系统中湖泊排入天坑是常见的现象，但对湖水、地下水、泉水和河水之间的关系却知之甚少。将大量湖水和含水污染物连续排入湖泊天坑，可以看作是一次自然示踪实验。如果在下坡岩溶泉水和河流中监测污染物浓度，则可以利用湖泊天坑排水来了解水和污染物的传输情况。为了测试这一点，该项目将使用人造染料示踪剂，并结合水化学测量，在一个排水活跃的湖泊天坑中进行测试。染料示踪剂和水化学将在湖泊、弗洛里丹上游含水层、喀斯特泉水和河流中进行监测和测量。这个项目的结果将与佛罗里达州地质调查局和环境管理机构分享。这个项目研究了岩溶系统中通过天坑、泉水和河口的湖泊排水之间的水文联系。染料示踪实验将被用来计算从活跃排水的湖泊天坑到下坡泉水和河流的穿越时间。为了评估环境示踪剂或污染物是否可以用作岩溶系统中染料示踪实验的替代品，将结合染料示踪剂进行发色溶解有机物测量。这项研究的结果和相关方法的开发可以应用于美国的许多其他岩溶系统。PIS将与佛罗里达州地质调查局合作，其结果将与州政府水资源和环境管理机构分享。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

Although lake drainage into sinkholes is common occurrences in karst systems, little is known about the relationships among lake water, groundwater, spring water, and river water. The continuous drainage of a large amount of lake water and water-contained contaminants into lake sinkholes can be viewed as a natural tracer experiment. If the contaminant concentrations are monitored in downgradient karst springs and rivers, the lake sinkhole drainage can be used to gain knowledge about the transport of water and contaminants. To test this, the project will use a man-made dye tracer along with water chemistry measurements to in an actively draining lake sinkhole. The dye tracer and water chemistry will be monitored and measured in the lake, the upper Floridan aquifer, karst springs, and rivers. Results from this project will be shared with the Florida State Geological Survey and environmental management agencies.This project examines the hydrologic connection among lake drainage via sinkholes, springs, and estuaries in a karst system. A dye tracer experiment will be used to calculate the transit time from an actively draining lake sinkhole to downgradient springs and rivers. To evaluate if environmental tracers or contaminants can be used as surrogates for dye tracer experiments in karst systems, chromophoric dissolved organic matter measurements will be taken in conjunction with the dye tracer. The results of this study and the associated methods development may be applied to many other karst systems in the U.S. The PIs will collaborate with the Florida State Geological Survey and their results will be shared with state government water resources and environmental management agencies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.