EAGER: Mercury and methylmercury isotope tracing in high-dissolved organic matter high-salinity environments

汞在野生动物中的积累是生态系统健康和人类健康的一个主要问题，人类狩猎和消费受汞影响的猎物（例如，鱼、鸭子和其他动物）。 通过测量生态系统中的汞同位素（例如，水、土壤、鱼类、鸟类）和不同的潜在汞来源（例如，废水）。 该项目旨在开发新的方法，以允许测量也具有高有机碳的盐水沃茨中的汞同位素（例如，河口、海洋系统和内陆盐湖），因为盐度和高有机碳的共存干扰了目前的汞同位素测量方法。 汞积累通常是有机碳含量高的盐水沃茨中的主要问题，因此开发允许在这些沃茨中测量汞同位素的方法将允许在这些环境中在地球仪中跟踪汞。 犹他州大学和美国地质调查局之间的这项合作研究关注的是，目前全球汞研究人员无法利用同位素方法阐明以下生物群的途径：a）含盐高溶解有机物（DOM）沃茨中的总汞; B）天然沃茨中的甲基汞，因为环境中甲基汞浓度低，抑制了同位素测量的应用和方法开发。 含盐的高DOM系统是全球生物群中汞污染物负荷的重要场所，包括黑海等海洋系统、大盐湖（GSL）等内陆沃茨、佛罗里达大沼泽地、旧金山弗朗西斯科湾、切萨皮克湾等河口系统以及全球许多其他城市化河口。 开发一种方法来克服DOM在盐水沃茨中的干扰作用，将允许阐明汞的途径，在这些系统中的生物群。 应用新开发的方法来阐明汞在大盐湖（犹他州）的简单食物网中的路径，将作为一个概念的证明，以刺激在其他地方的应用。 GSL的总汞和甲基汞浓度升高，GSL的简单生态系统，以及GSL易于处理的大小和深度，使其成为拟议方法的理想孵化器。助理，以及教师在培训作为候选人在科学硕士在中学科学教学（MSSST）研究生课程在犹他州，谁将在夏季和秋季实习指导大学。 该计划涉及初中和高中生物，化学，和地球科学教师在为期六周的夏季实习，最终在秋季学期结束时，在教师开发的一系列等级-该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响进行评估来支持审查标准。

Mercury accumulation in wildlife is a major concern for both ecosystem health and the health of humans who hunt and consume mercury-impacted prey (e.g., fish, ducks, and other animals). Tracing the pathways by which mercury enters the food chain and propagates to animals is successfully done by measuring mercury isotopes in the ecosystem (e.g., water, soil, fish, birds) and in different potential mercury sources (e.g., wastewaters). This project seeks to develop new methods to allow measurement of mercury isotopes in saline waters that also have high organic carbon (e.g., estuaries, marine systems, and inland salt lakes) since the co-occurrence of salinity and high organic carbon interfere with current measurement methods for mercury isotopes. Mercury accumulation is often a major concern in saline waters with high organic carbon, and so development of methods to allow mercury isotope measurements in these waters will allow mercury tracking in these settings across the globe. This collaborative research between University of Utah and the US Geological Survey concerns the current inability of mercury researchers globally to utilize isotopic methods to elucidate pathways to biota for: a) total mercury in saline high dissolved organic matter (DOM) waters; and b) methyl mercury in natural waters where low ambient methyl mercury concentrations inhibit application and method development for isotope measurements. Saline high-DOM systems are important locations globally for mercury contaminant burdens in biota, including marine systems such as the Black Sea, inland waters such as Great Salt Lake (GSL), and estuarine systems such as the Florida Everglades, San Francisco Bay, Chesapeake Bay, and many other urbanized estuaries worldwide. Developing a method to overcome the interfering effects of DOM in saline waters will allow elucidation of mercury pathways to biota in these systems. Application of the newly-developed methodology to elucidate mercury pathways to the simple food web in Great Salt Lake (Utah) will serve as a proof of concept to spur application in other locales. The elevated total mercury and methyl mercury concentrations at GSL, the simple ecosystem at GSL, and the tractable size and depth of GSL, make it an ideal incubator for the proposed methodology.Broader impacts include training of a Ph.D. assistant, as well as teachers-in-training as candidates in the Masters of Science in Secondary School Science Teaching (MSSST) graduate program at the University of Utah, who will be mentored during summer-fall internships. The program engages middle and high school biology, chemistry, and earth science teachers in six-week long summer internships that culminate at the end of the fall semester in a teacher-developed series of grade-appropriate lesson plans through which teachers will impact over 600 students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.