U.S.-South Africa Planning Visit: Determination of Sediment Sources and Transport Pathways Using Multivariate Geochemical Fingerprinting, in Mgeni and Berg Catchments, South Africa

非点源(NPS)污染是包括美国在内的大多数发达国家地表水退化的主要原因。事实证明，从广泛分散的污染源地区控制NPS污染物，如沉积物和营养物质，是一个极其困难和昂贵的过程。此次规划访问的长期目标是与南非水研究委员会(WRC)共同制定一项国际多学科研究计划，以更好地了解如何有效管理NPS污染物。对南非的计划访问将使我们能够与我们的合作者会面，并参观潜在的实地地点。这次访问将使我们能够更好地开发一个合作研究计划，该计划可以(1)改进从单个农业地块到整个流域的连续空间尺度上的泥沙和营养物质向河流和水库输送的概念和数学模型，(2)开发基于地球化学的新方法来跟踪通过流域的NPS污染物，以及(3)评估迁移过程中生物地球化学循环对污染物的传输和储存。该项目将建立在世界资源中心开发核动力源污染预测性管理工具的现有计划的基础上。我们的合作将是互惠互利的，因为美国团队将有机会利用WRC的广泛现场仪器、数据和专业知识，同时提供一套不同但互补的方法来调查沉积物和营养物质。我们预计接下来的项目将为本科生和研究生提供研究经验，并将改进预测NPS污染物对南非和美国水生资源的影响的方法。

Non-point source (NPS) pollution is a leading cause of surface water degradation in most developed countries, including the U.S. Controlling NPS pollutants, such as sediment and nutrients, from widely dispersed source areas has proven to be an extremely difficult and expensive process. The long-term goal of this planning visit is to develop an international, multidisciplinary research program with the South African Water Research Commission (WRC) that results in a better understanding of how to effectively manage NPS pollutants. The planning visit to South Africa will enable us to meet with our collaborators and to visit potential field sites. This visit should allow us to better develop a collaborative research program that can (1) improve upon conceptual and mathematical models of sediment and nutrient delivery to streams and reservoirs over a continuum of spatial scales, ranging from an individual agricultural plot to the entire watershed, (2) develop new, geochemically-based methods of tracking NPS pollutants through watersheds, and (3) evaluate transport and storage of pollutants by biogeochemical cycles during migration. This project will build upon an existing program by the WRC to develop predictive management tools for NPS pollution. Our collaborations will be mutually beneficial as the U.S. team will have the opportunity to utilize WRC's extensive field instrumentation, data, and expertise while providing a different, but complimentary set of approaches to the investigation of sediment and nutrients. We expect that the ensuing program will provide research experiences for undergraduate and graduate students and will result in improved methods of predicting the impact of NPS pollutants on aquatic resources, both in South Africa and the U.S.