International Planning Visit: Investigating the Interactions Between Dissolved Organic Matter, Microbial Communities, and Arsenic Biogeochemistry in Groundwater of a Pristine Delt

这次计划访问将开发一个国际合作研究和培训项目，主题是博茨瓦纳奥卡万戈三角洲地下水中溶解有机物、微生物群落和砷生物地球化学之间的相互作用。此次计划访问将汇集来自科罗拉多大学和堪萨斯州立大学的美国科学家和工程师，以及博茨瓦纳地质调查局和奥卡万戈研究所(ORI)的科学家，以制定令人信服的研究计划，收集样本进行初步分析，并会见毛恩高中的科学教师，为美国K-12教师计划未来的教育推广活动。研究小组还将检查ORI的实验室设施，确定实地研究地点，为参与研究的研究生寻找合适的国内导师，并开始准备针对NSF耳朵水文科学(HS)部门的研究提案。智力优势：地下水中天然存在的砷是一个全球性问题，对全球数百万人的健康造成严重影响，但人们对从沉积物中动员砷的过程还不太清楚。这次规划访问将协调未来的研究，以发展对富含金属氧化物的沉积物中有机物和微生物之间的反应的过程水平的了解，这些反应影响地下水中砷的动员。更好地了解沿地下水流动路径的溶解有机物转化和与流动路径相关的微生物群落组成的变化，对于了解(和预测)不同地下水环境中砷的迁移是极其重要的。奥卡万戈三角洲岛屿特有的蒸散驱动的地下水流动提供了一个独特的机会，可以调查与微生物群落的演变和导致砷动员的相关生物地球化学过程有关的问题。更广泛的影响：除了扩大科学界对地下水砷污染这一全球问题的理解之外，这次规划访问还将支持两名研究生，他们将有机会从项目概念开始就参与到项目中来。美国科学家和教师在毛恩高中的会议将建立新的关系，这些关系将以教师研究经验和本科生研究经验的形式为未来的教育推广奠定基础。

This planning visit will develop an international collaborative research and training project on the topic of interactions between dissolved organic matter, microbial communities, and arsenic biogeochemistry in groundwater of the Okavango Delta, Botswana. The planning visit will bring together U.S. scientists and engineers from the University of Colorado and Kansas State University with scientists from the Botswana Geologic Survey and the Okavango Research Institute (ORI) to develop a compelling research plan, collect samples for preliminary analyses, and meet with science teachers from Maun Senior Secondary School to plan future educational outreach activities for U.S. K-12 teachers. The research team will also examine the laboratory facilities at ORI, identify field research sites, identify appropriate in-country mentors for graduate students involved in the research, and begin preparation of a research proposal targeted for the NSF EAR Hydrologic Sciences (HS) division. Intellectual merit: Naturally-occurring arsenic in groundwater is a global problem with serious health consequences for millions of people worldwide, yet the processes by which arsenic is mobilized from sediments are not well understood. This planning visit will coordinate future research to develop a process-level understanding of the reactions between organic matter and microorganisms in metal oxide-rich sediments that influence arsenic mobilization in groundwater. The improved understanding of dissolved organic material transformations along groundwater flow paths and flow path-related shifts in microbial community composition is extremely important for understanding (and predicting) arsenic mobilization in diverse groundwater environments. The evapotranspiration-driven groundwater flow that is characteristic of islands in the Okavango Delta provides a unique opportunity to investigate questions related to the evolution of microbial communities and associated biogeochemical processes that lead to arsenic mobilization. Broader impacts: In addition to broadening the understanding of the scientific community understanding on the global problem of groundwater arsenic contamination, this planning visit will support two graduate students, who will have the opportunity to be involved in the project from its conception. Meetings between US scientists and teachers at Maun Senior Secondary School will build new relationships that are the basis for future educational outreach in the form of Research Experience for Teachers and Research Experience for Undergraduates.