CAREER: Fundamental Understanding of Mercury Cycling in Lakes and Use of Reservation-Based Research to Recruit American Indians into Environmental Engineering and Science

CBET-0846446 Beutel，Marc.湖泊中的厌氧底层沃茨和深层沉积物是汞甲基化（MeHg）的重要场所。该项目的主要目标是更好地了解关键环境因素，特别是溶解氧（DO），如何影响甲基汞在湖泊沉积物和底层沃茨中的循环。核心假设是，溶解氧渗透到深海沉积物控制甲基汞循环：（1）抑制甲基汞的生物生产和释放从表层沉积物，（2）抑制释放，随后的水柱甲基化，有机汞络合物结合到金属氧化物在表层沉积物。溶解氧和大型底栖动物密度对深水沉积物中汞循环的影响将根据完整的深水沉积物-水样从南双子湖的科尔维尔印第安保留区和实验室样品收集在实验室。拟议的研究和教育计划在主题和地理上都是紧密结合的。在湖泊中骑汞自行车的总体主题推动了一项雄心勃勃的研究计划和一项创造性的推广计划，这两项计划都侧重于西澳东部的科尔维尔印第安人保留地。这些综合方案将促进发现湖泊中的汞循环，同时促进美洲印第安高中生、本科生和研究生的学习。扩大代表性不足群体的参与是该项目教育计划的核心。对美国印第安学生的宣传，分享科学发现的兴奋与有针对性的招聘工作相结合，最终将导致美国印第安人在环境工程和科学中的代表性增加。

CBET- 0846446Beutel, MarcAnaerobic bottom waters and profundal Sediments in lakes are important sites of mercury methylation (MeHg). The principal objective of this project is to better understand how key environmental factors, especially dissolved oxygen (DO), would influence MeHg cycling in lake sediments and bottom waters. The central hypothesis is that DO penetration into profundal sediments controls MeHg cycling by: (1) repressing MeHg bioproduction and release from surficial sediments, and (2) inhibiting the release, and subsequent water column methylation, of organo-Hg complexes bound to metal oxides in surficial sediments. Effects of DO and macrofauna density on Hg cycling in profundal sediments will be investigated based on intact prohundal sediment-water samples to be obtained from South Twin Lake on the Colville Indian Reservation and laboratory samples to be collected in the laboratory chambers. The proposed research and educational plans are tightly integrated both topically and geographically. The overarching theme of Hg cycling in lakes drives both an ambitions research program and a creative outreach program, with both programs focused on the Colville Indian Reservation in Eastern WA. The integrated programs will advance discovery related to Hg cycling in lakes while promoting learning by American Indian high school students, undergraduates and graduate students. Broadening participation of underrepresented groups is at the core of the project's educational plan. Outreach to American Indian students that shares the thrill of scientific discovery combined with targeted recruitment efforts will ultimately result in increased representation of American Indians in environmental engineering and science.