Collaborative Research: Chemistry of Groundwater Transport Pathways Associated with a Coastal Lagoon System

合作研究：与沿海泻湖系统相关的地下水输送路径的化学

• 批准号: 0233657
• 负责人: Willard Moore
• 金额: --
• 依托单位: University South Carolina Research Foundation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-01-15 至 2007-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0233657&HistoricalAwards=false
• 关键词: Collaborative; Research; Chemistry; Groundwater; Transport

Under this award, study will focus on understanding of reaction and transport pathways in permeable sediments and will attempt to determine how nutrients and other trace substances are transported and modified in the subterranean freshwater-seawater mixing zone connecting a Brazilian lagoon to the adjacent ocean. The study will also evaluate how these processes are altered by hydrologic forcing conditions. The field area is the barrier spit adjacent to the Patos Lagoon on the extreme southern coast of Brazil. This site was chosen because: 1) the PIs preliminary results demonstrate that this region is favorable to Submarine Groundwater Discharge (SGD) and they anticipate large chemical signals and exchange rates. 2) it is relatively unimpacted by human activity. 3) there are two ILTER Programs focused on this system, and 4) this system provides a contrast to the southeastern US coast. This study will identify relevant reactions and estimate the fluxes of nutrients and trace elements (using radium isotopes). The PIs will detenrnine if permeable sediments are a significant source or sink for the materials of interest, which reaction pathways control their behavior in the sediments, and how processes are affected by external forcing (primarily lagoon water level). The project has three components: 1) field campaigns, 2) laboratory kinetic experiments, and 3) synthesis of results through qualitative and quantitative analyses and simple numerical simulations. Field work will involve placement of wells both across the barrier spit and along the beach on the ocean side, benthic chamber deployments, and coastal cruises, the latter to establish offshore gradients of radium isotopes to assess SGD fluxes. Laboratory studies will use core cuttings in flow-through plug reactors to assess better the nature and kinetics of reactions. And finally, numerical simulations will be used to aid in interpreting results.

根据该奖项，研究将集中于对可渗透沉积物中的反应和运输途径的理解，并将试图确定如何在地下淡水 - 盐水混合区中运输和修改营养物质和其他微量物质，将巴西泻湖连接到邻近海洋。该研究还将评估这些过程如何通过水文强迫条件改变。野外区域是巴西极端海岸的Patos泻湖附近的障碍物。之所以选择该地点是因为：1）PIS初步结果表明该区域有利于海底地下水排放（SGD），并且他们预计大量的化学信号和汇率。 2）人类活动相对没有影响。 3）有两个重点关注该系统的ILTER计划，4）该系统与美国东南部海岸提供了鲜明的对比。这项研究将确定相关的反应，并估计营养和微量元素的通量（使用赖赖和华同位素）。如果可渗透的沉积物是感兴趣的材料的重要来源或下沉，则PIS将延伸，反应途径控制其在沉积物中的行为，以及过程如何受到外部强迫的影响（主要是泻湖水位）。该项目具有三个组成部分：1）现场活动，2）实验室动力学实验，3）通过定性和定量分析和简单的数值模拟综合结果。现场工作将涉及在整个障碍物吐口水和海滩的海滩，底栖室的部署和沿海巡游中放置井，后者建立了辐射辐射量同位素的近海梯度，以评估SGD通量。实验室研究将在流通塞反应堆中使用核心插条，以更好地评估反应的性质和动力学。最后，数值模拟将用于帮助解释结果。