Collaborative Research: Microbial Observatory at an Alkaline, Hypersaline, Meromictic Lake (Mono Lake, California)

合作研究：碱性、超盐、半罗密湖（加利福尼亚州莫诺湖）的微生物观测站

• 批准号: 9977892
• 负责人: Jonathan Zehr
• 金额: $ 24.82万
• 依托单位: University of California-Santa Cruz
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-10-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9977892&HistoricalAwards=false
• 关键词: Collaborative; Research; Microbial; Observatory; Alkaline

The Microbial Observatory focuses on the microbes found in Mono Lake, an alkaline, hypersaline, currently meromictic (lighter, less saline water overlies heavier, more saline water throughout the year) lake located east of the Sierra Nevada in California. There are a number of reasons why Mono Lake is an ideal site for a Microbial Observatory. It is a well-defined, ecologically simple, microbially dominated ecosystem for which long-term ecological and limnological data exist. Mono Lake is a hydrologically simple system, which makes modeling tractable, yet it contains complex gradients of chemical and physical variables as a result of meromixis. The lake is located close to a major field station (the Sierra Nevada Aquatic Research Laboratory, administered by the University of California, Santa Barbara). There are ongoing studies of the lake's physics, plankton ecology and biogeochemistry that provide a comprehensive framework for the microbial studies. Mono Lake is currently undergoing a human-induced (and thus predictable) limnological transition which imparts a predictable temporal trajectory to physical, biogeochemical and ecological processes. This change mirrors past, natural events in Great Basin lakes resulting from climate oscillations and similar, if less extreme, changes in physical limnology might be expected in other lakes. Mono Lake represents an extreme environment that is likely to harbor unique microbes. However, relatively little is known about the types of microorganisms dwelling in Mono Lake, their phylogenetic diversity, taxonomy, ecology or ecophysiology. For example, recent phylogenetic analysis of an important phytoplankton demonstrates it to be a new class of algae with unusual physiological properties and biochemical composition. While abundant bacterial populations and the existence of pronounced bacterial plates have been noted before in Mono Lake, the temporal and spatial variation in diversity of the bacterial community has only recently begun to be investigated. The primary goal of this research is to examine the distributions of Mono Lake microbes and to understand the response of microbial assemblages to the gradients of physical and chemical variables in relation to temporal changes driven by hydrodynamics. The specific objectives of the project are to: 1) Identify and characterize the microbial assemblages in the unique Mono Lake ecosystem. 2) Determine the spatial and temporal variation of the Mono Lake microbial assemblage, particularly in reference to evolving meromixis. 3) Determine the response of the microbial community to physical processes, especially short-term and small-scale variation in mixing (for example, enhanced vertical diffusion as a result of boundary mixing or localized gravitational circulation). 4) Provide a mechanistic understanding of the interactions between the physical/chemical structure and microbial assemblages as the basis for predictive (long-term) modeling of the relationship between microbial processes, lake biogeochemistryand primary production. This project provides a unique opportunity to identify novel microorganisms and define interactions among microorganisms in complex gradients of physical/chemical conditions usually only encountered at sediment-water interfaces. This is a collaborative project involving Drs. James Hollibaugh and Samantha Joye, University of Georgia, award #9977886, Dr. Robert Jellison, University of California, Santa Barbara (#9977901) and Dr. Jonathan Zehr, University of California, Santa Cruz (#9977892).

微生物天文台的重点是在碱性湖中发现的微生物，碱性，高盐酸盐，目前是美细菌的（较轻，较少的盐水水叠加较重，全年盐水更大），位于加利福尼亚州内华达州塞拉利亚山脉以东。 Mono Lake是微生物天文台的理想场所，有很多原因。它是一个定义明确的，生态简单的，微生物统治的生态系统，存在长期的生态和元数据学数据。 Mono Lake是一种水文简单的系统，可以使建模可进行，但由于Meromixis而包含化学和物理变量的复杂梯度。该湖靠近大型野外车站（由加利福尼亚大学圣塔芭芭拉分校管理的内华达州内华达州水上运动实验室）。正在进行关于湖泊物理学，浮游生物生态学和生物地球化学的研究，这些研究为微生物研究提供了全面的框架。 Mono Lake目前正在经历人类引起的（可预测的）林理学转变，该过渡赋予物理，生物地球化学和生态过程的可预测的时间轨迹。这种变化反映了过去的大流域湖泊中的自然事件，这是由于气候振荡而导致的，并且在其他湖泊中可能会发生类似的物理林木学变化（如果不太极端）。 Mono Lake代表了一个可能具有独特微生物的极端环境。但是，关于单湖中居住的微生物类型，其系统发育多样性，分类学，生态学或生态生理学的类型相对较少。例如，对重要浮游植物的最新系统发育分析证明了它是具有异常生理特性和生化组成的新藻类。虽然在单湖之前已经注意到了大量细菌种群和明显的细菌板的存在，但细菌群落多样性的时间和空间变化直到最近才开始研究。这项研究的主要目的是检查单湖微生物的分布，并了解微生物组合对物理和化学变量梯度的响应，相对于流体动力学驱动的时间变化。该项目的具体目标是：1）识别和表征独特的单湖生态系统中的微生物组合。 2）确定单湖微生物组合的空间和时间变化，尤其是在不断发展的Meromixis方面。 3）确定微生物群落对物理过程的响应，尤其是混合中的短期和小规模变化（例如，由于边界混合或局部重力循环而增强的垂直扩散）。 4）提供了对物理/化学结构和微生物组合之间相互作用的机械理解，这是对微生物过程，生物地球化学和一级生产之间关系的预测性（长期）建模的基础。该项目提供了一个独特的机会，可以识别新型微生物，并在通常仅在沉积物 - 水接口处遇到的物理/化学条件的复杂梯度中微生物之间的相互作用。这是一个涉及DRS的协作项目。詹姆斯·霍利博（James Hollibaugh）和萨曼莎·乔伊（Samantha Joye），佐治亚大学，奖＃9977886，罗伯特·杰里森（Robert Jellison）博士，加利福尼亚大学，圣塔芭芭拉分校（＃9977901）和加利福尼亚大学乔纳森·泽尔（Jonathan Zehr）博士，圣克鲁斯（Santa Cruz）（＃9977892）。