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厌氧底层水和湖泊深海沉积物是汞甲基化的重要场所。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)将如何影响湖泊沉积物和底层水中的甲基汞循环。中心假设是DO渗透到深海沉积物中，通过：(1)抑制表层沉积物中甲基汞的生物产生和释放，以及(2)抑制表层沉积物中金属氧化物结合的有机汞络合物的释放和随后的水柱甲基化，从而控制甲基汞的循环。DO和大型动物密度对深海沉积物中汞循环的影响将基于从科尔维尔印第安人保护区南双子湖获得的完整沉积物水样和实验室采集的实验室样品进行研究。拟议的研究和教育计划在专题和地理上都紧密结合在一起。在湖泊中骑汞自行车的主旋律推动了一个雄心勃勃的研究计划和一个创造性的推广计划，这两个计划都侧重于西澳大利亚东部的科尔维尔印第安人保留地。这些综合项目将促进与在湖泊中骑汞自行车相关的发现，同时促进美国印度高中生、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。与美国印第安人学生分享科学发现的兴奋，再加上有针对性的招生工作，最终将导致美国印第安人在环境工程和科学领域的代表性增加。

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.