COLLABORATIVE RESEARCH: Biogeochemical Exploration of Acidic and Neutral Hypersaline Environments of Australia

合作研究：澳大利亚酸性和中性超盐环境的生物地球化学勘探

• 批准号: 0433040
• 负责人: Kathleen Benison
• 金额: --
• 依托单位: Central Michigan University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-01-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0433040&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Biogeochemical; Exploration; Acidic

EAR-0433040BenisonAn NSF Biogeosciences grant has been awarded to Drs. Melanie R. Mormile, Francisca E. Oboh-Ikuenobe (University of Missouri-Rolla), and Kathleen C. Benison (Central Michigan University) to determine if evaporites truly trap a representative population of microorganisms from hypersaline environments. If this is found to be true, these findings can possibly be extrapolated to microorganisms entrapped in ancient or possibly extraterrestrial evaporites and used to describe previous microbial communities and therefore, make interpretations about past water chemistries and past climates. Microorganisms represent the basic life forms existing in most environmental settings. They are sensitive to climatic parameters, and can influence water chemistry, biological activity, and mineralization. Evaporite minerals are a wealth of paleoenvironmental data due to their sensitivity to climate, water chemistry, and hydrology. In addition, evaporites can form in extreme environmental conditions, such as extremely acid saline lakes in Western Australia. These lakes might serve as good analogs to Mars. Traditionally, studies of evaporite settings and their deposits have overlooked microorganisms largely because they are generally poorly preserved in the rock record. However, through this research, answers to the following questions will be found: What microorganisms are present in the lake waters, groundwaters, and sediments of acid and neutral saline lake environments? Are the microorganisms found living in the waters represented in the fluid inclusions of the evaporite minerals? Are the microorganisms specific acidophiles? What role did the microorganisms play in the evolution of the water chemistry? To answer these questions, a sampling trip will be made to Australia to collect a comprehensive set of lake water, groundwater, evaporite, and siliciclastic sediment samples. The following objectives will be achieved: 1. Identify and compare the biological remains in halite and gypsum with those in their parent waters and sediments. Both traditional culture methods and molecular biology techniques will be used to compare the microbial populations in the environments listed above. 2. Grow evaporite crystals under laboratory conditions to study selected environmental influences on crystal formation and the microorganisms that become entrapped. 3. Identify any differences in microorganisms (ranging from prokaryotes to freshwater dinoflagellates and algae) between neutral and moderately acidic saline lakes and groundwaters in Victoria and Western Australia, between neutral and extremely acidic saline lakes within a small region of Western Australia, as well as among extremely acidic saline lakes and groundwaters in Western Australia. The 16S rDNA from the bacteria isolated from these environments will be sequenced and compared. 4. Constrain depositional, environmental, and climatic conditions using basic sedimentology, petrography, fluid inclusion studies, and palynology. Sedimentary structures and grain characteristics will be used to trace depositional history. We anticipate that novel microorganisms will be found. These organisms can possibly be used for the bioremediation of contaminated sites that are impacted by extremes in saline and acidic conditions. In addition, our findings will have implications for future Mars research and the possibility that life can occur on planetary bodies besides Earth. Of all the planetary bodies explored, Mars most closely resemble Earth. In particular, terrestrial acid sedimentary systems are similar in general mineralogy, geochemistry, and geomorphology to the Martian surface. Furthermore, this project will be responsible for the training of students ranging from undergraduate level to Post-Doctoral students. There is also a significant outreach component that includes a partnership with the St. Louis Science Center as well as a course on the geology and microbiology of extreme environments targeted towards K-12 educators.

EAR-0433040贝尼森NSF生物地质科学奖授予梅勒妮·R·莫尔迈尔博士、弗朗西斯卡·E·奥波-伊库诺贝博士(密苏里大学罗拉分校)和凯瑟琳·C·贝尼森(中密歇根大学)，以确定蒸发岩是否真的捕获了来自高盐度环境的代表性微生物种群。如果发现这是真的，这些发现可能被推断为困在古代或可能是外星蒸发岩中的微生物，并被用来描述以前的微生物群落，从而对过去的水化学和过去的气候做出解释。微生物代表了存在于大多数环境中的基本生命形式。它们对气候参数很敏感，可以影响水化学、生物活性和矿化作用。由于蒸发岩矿物对气候、水化学和水文学的敏感性，它们是丰富的古环境数据。此外，蒸发岩可以在极端环境条件下形成，例如西澳大利亚的极端酸性盐湖。这些湖泊可以很好地类比火星。传统上，对蒸发岩环境及其沉积的研究忽略了微生物，很大程度上是因为它们在岩石记录中通常保存得很差。然而，通过这项研究，将找到以下问题的答案：酸性和中性盐湖环境的湖水、地下水和沉积物中存在哪些微生物？水中发现的微生物是否存在于蒸发岩矿物的流体包裹体中？这些微生物是不是特定的嗜酸菌？微生物在水化学的进化中扮演了什么角色？为了回答这些问题，将前往澳大利亚进行一次采样旅行，收集一套全面的湖水、地下水、蒸发岩和硅质碎屑沉积物样本。将实现以下目标：1.鉴定岩盐和石膏中的生物残留物，并与其母水域和沉积物中的生物残留物进行比较。将使用传统的培养方法和分子生物学技术来比较上述环境中的微生物种群。2.在实验室条件下生长蒸发岩晶体，研究选定的环境对晶体形成的影响以及被捕获的微生物。3.查明维多利亚州和西澳大利亚州中性和中等酸性盐湖和地下水之间、西澳大利亚州一小块区域内中性和极酸性盐湖之间以及西澳大利亚州极酸性盐湖和地下水之间微生物(从原核生物到淡水甲藻和藻类)的任何差异。从这些环境中分离的细菌的16S rDNA将被测序并进行比较。4.使用基础沉积学、岩石学、流体包裹体研究和孢粉学来约束沉积、环境和气候条件。沉积构造和颗粒特征将用于追踪沉积历史。我们预计会发现新的微生物。这些微生物可能用于受极端盐碱和酸性条件影响的受污染场地的生物修复。此外，我们的发现将对未来的火星研究以及地球以外的行星上可能存在生命的可能性产生影响。在所有被探测的行星体中，火星与地球最为相似。特别是，陆源酸性沉积系统在一般矿物学、地球化学和地貌上与火星表面相似。此外，该项目将负责培养从本科生到博士后的学生。还有一个重要的外联部分，其中包括与圣路易斯科学中心的伙伴关系，以及针对K-12教育工作者的极端环境地质学和微生物学课程。