Collaborative Research: Geochemistry and Microbiology of the Extreme Aquatic Environment in Lake Vida, East Antarctica

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。维达湖是麦克默多干谷最大的湖泊，约20米的冰盖覆盖着未知深度的盐水，盐度至少是海水盐度的7倍，全年温度低于-10摄氏度。从主要水体上方的冰中收集的盐水样本含有1）地球上任何天然水体中最高的一氧化二氮水平，2）不寻常的地球化学，包括异常高的氨和铁浓度，3）高微生物计数，其中超微细菌的比例不寻常（99%）。 即使与其他干谷湖泊相比，微生物群落也是独一无二的。该研究计划首次进入维达湖厚冰层下的主要卤水体，进行现场测量，收集卤水柱样品，并从湖底收集沉积物芯，进行详细的地球化学和微生物分析。结果将允许在湖的现在和过去的生活，现代和过去的沉积过程的评估，并确定湖泊的历史的特点。该研究将由一个多学科团队进行，该团队将揭示与非光合微生物群落隔离相当长一段时间相关的生物地球化学过程。这项研究将在维达湖环境物理演变的背景下探讨多样性、适应机制和演变过程。将通过出版物、在国家和国际会议上的介绍、冰下南极湖勘探网站和麦克默多远程环境关系网站广泛传播研究结果。这项研究将支持三名研究生和三名本科生研究助理。 研究结果将被纳入芝加哥伊利诺伊大学一门新的本科生生态科学课程中。芝加哥大学的学生群体极其多样化，以少数族裔为主。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)Lake Vida is the largest lake of the McMurdo Dry Valleys, with an approximately 20 m ice cover overlaying a brine of unknown depth with at least 7 times seawater salinity and temperatures below -10 degrees C year-round. Samples of brine collected from ice above the main water body contain 1) the highest nitrous oxide levels of any natural water body on Earth, 2) unusual geochemistry including anomalously high ammonia and iron concentrations, 3) high microbial counts with an unusual proportion (99%) of ultramicrobacteria. The microbial community is unique even compared to other Dry Valley Lakes. The research proposes to enter, for the first time the main brine body below the thick ice of Lake Vida and perform in situ measurements, collect samples of the brine column, and collect sediment cores from the lake bottom for detailed geochemical and microbiological analyses. The results will allow the characterization of present and past life in the lake, assessment of modern and past sedimentary processes, and determination of the lake's history. The research will be conducted by a multidisciplinary team that will uncover the biogeochemical processes associated with a non-photosynthetic microbial community isolated for a significant period of time. This research will address diversity, adaptive mechanisms and evolutionary processes in the context of the physical evolution of the environment of Lake Vida. Results will be widely disseminated through publications, presentations at national and international meetings, through the Subglacial Antarctic Lake Exploration (SALE) web site and the McMurdo LTER web site. The research will support three graduate students and three undergraduate research assistants. The results will be incorporated into a new undergraduate biogeosciences course at the University of Illinois at Chicago which has an extremely diverse student body, dominated by minorities.