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

beutel， marca -好氧底水和湖泊深层沉积物是汞甲基化（MeHg）的重要场所。该项目的主要目的是更好地了解关键环境因素，特别是溶解氧（DO）如何影响湖泊沉积物和底部水域的甲基汞循环。核心假设是，DO渗透到深层沉积物中，通过以下方式控制MeHg循环：(1)抑制表层沉积物中MeHg的生物生成和释放，以及(2)抑制表层沉积物中与金属氧化物结合的有机汞配合物的释放和随后的水柱甲基化。基于从科尔维尔印第安保留区南双子湖获得的完整深海沉积物水样和在实验室室收集的实验室样品，将研究DO和大型动物密度对深海沉积物中汞循环的影响。拟议的研究和教育计划在主题和地理上都紧密结合在一起。湖泊中汞循环的首要主题推动了一个雄心勃勃的研究项目和一个创造性的推广项目，这两个项目都集中在西澳大利亚州东部的科尔维尔印第安人保留地。这些综合项目将推进与湖泊中汞循环有关的发现，同时促进美国印第安高中生、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的教育计划的核心。与美国印第安学生分享科学发现的兴奋，结合有针对性的招聘努力，最终将增加美国印第安人在环境工程和科学领域的代表性。

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.