Collaborative Research: Suspended Sediment Transport in Karst

0125551白色虽然它似乎直观明显，岩溶含水层将携带更多的沉积物比多孔介质含水层，因为大导管和更快的速度，相对较少的研究试图量化岩溶泥沙输运。 了解沉积物的输运是很重要的，原因有很多。 第一，沉积物可能会增强附着在沉积物上的污染物的迁移。 第二，沉积物的流动性也反映了细菌和病毒的潜在流动性，这是评价地下水质量时所关注的问题。 第三，沉积物的流动性是衡量岩溶中的速度和运输途径的一个指标，这是一个复杂的问题，涉及到不同水库的混合，很难量化。 这项研究将解决泥沙输运如何随季节和不同的风暴事件的变化，通过测量一组岩溶含水层的泥沙输运在一年的过程中，在几个不同类型的风暴事件。 风暴事件将包括小型和大型风暴，加上潮湿和干燥的先决条件的风暴。 选择了三个不同的岩溶含水层，包括高、中和低流量系统。 在每个站点，将安装连续记录仪来监测电导率、流量和浊度，以记录季节变化和风暴的前期条件。 此外，雨水采样器将在选定的风暴事件期间自动触发采样。 每月和风暴期间收集的样本将进行详细的水化学，沉积物成分和沉积物粒度分布分析。 将努力模拟岩溶含水层内沉积物运动的输运过程。 实地考察和模拟相结合，以评估对泥沙输运的控制，将被用来分类不同的岩溶系统使用的混合比隐含的泥沙输运。从不同的水库解开混合是很重要的岩溶和非岩溶系统，这项研究将有助于显示时间的异质性（风暴事件之间的变化，而不仅仅是风暴事件）可以提供线索的内部结构的系统。 这项工作将通过研究端元系统（岩溶）和量化了解系统响应所需的测量类型来证明水文系统中时间异质性的重要性。

0125551WhiteAlthough it seems intuitively obvious that karst aquifers will carry more sediment than porous media aquifers, because of the large conduits and faster velocities, relatively few studies have tried to quantify sediment transport in karst. Understanding sediment transport is important for a number of reasons. First, sediment may enhance transport of contaminants that are mobilized by attaching to sediment. Second, the mobility of sediment also reflects the potential mobility of bacteria and viruses, which are of concern in evaluating groundwater quality. And third, the mobility of sediment is a measure of velocities and transport pathways in karst, a complex issue involving mixing from different reservoirs, which is difficult to quantify. This research will address how sediment transport varies with seasons and different storm events by measuring sediment transport in a set of karst aquifers over the course of a year and during several different types of storm events. Storm events will include small and large storms, plus storms with wet and dry antecedent conditions. Three distinct karst aquifers have been selected that include a high, medium, and low discharge system. At each site, continuous loggers will be installed to monitor conductance, discharge, and turbidity to record seasonal variation and antecedent conditions for storms. In additional, stormwater samplers will automatically trigger to sample during the selected storm events. Samples collected monthly and during storms will be analyzed for detailed water chemistry, sediment composition, and sediment size distribution. Efforts will be made to model the transport processes for sediment movement within karst aquifers. The combination of fieldwork and modeling to assess the controls on sediment transport will be used to classify the different karst systems using the mixing ratios implied by sediment transport. Unraveling mixing from different reservoirs is important in both karst and non-karst systems, and this study will help show how temporal heterogeneity (changes between storm events, not just within storm events) can provide clues to the internal structure of a system. This work will demonstrate the importance of temporal heterogeneity in hydrologic systems by studying an end-member system (karst) and quantifying the types of measurements needed to understand system response.