Collaborative Research: MO: Forces Driving Microbial Community Diversity and Composition in Humic Lakes

微生物负责淡水湖中的大部分碳和养分循环，并影响当地水质和全球碳收支。然而，目前还不可能预测在特定的时间在特定的湖泊中会发现哪种类型的微生物，或者预测微生物群落如何对环境变化做出反应。微生物生物学家需要更多地了解湖泊中的微生物如何聚集成群落，竞争、捕食、资源可用性、干扰和自然选择等驱动因素在形成这些组合中的作用。这个项目解决了以下首要问题：是什么力量在腐殖质湖泊中组织微生物群落？微生物及其群落对作用在不同时空尺度上的许多力作出反应，这些力的影响可以在群落和种群水平上观察到。一个由微生物学家、生态学家、工程师和湖沼学家组成的跨学科团队将使用一套分子工具和基因组学来研究(1)湖泊表层细菌和浮游植物之间的相互作用；(2)热分层和季节混合等水柱扰动导致的微生物群落变化；(3)进化过程在湖泊内部和湖泊之间形成单个微生物种群中的作用。这项工作的结果将使我们能够更好地解释和最终预测淡水湖泊微生物群落和种群的组成和动态。该项目不仅将促进我们对腐殖质湖泊微生物生态的理解，而且将在更广泛的背景下促进微生物生态和生物多样性的理解。该研究方法是在生态框架内构建的，反映了微生物生物学领域的迫切问题。为了加强这项工作的广泛影响，调查人员将与下列组织协调开展外联活动；NTL-LTER校园科学计划，通过为高中教师举办讲习班，促进探究性学习；为初高中科学和数学教师开发虚拟专业发展资源的生物教育中心；威斯康星大学麦迪逊分校的PEOPLE项目，该项目为代表性不足的高中生组织暑期课程；美国国家科学基金会资助的教学、研究和学习整合中心，旨在促进研究生、博士后和教师的专业发展。研究小组将继续利用这些现有的项目向公众展示淡水微生物是湖泊生态系统的关键组成部分，如何以深刻的方式影响水质和营养循环。

Microbes are responsible for most of the carbon and nutrient cycling in freshwater lakes, and influence both local water quality and global carbon budgets. However, it is not currently possible to predict which types of microbes will be found in a particular lake at a particular time, or to predict how a microbial community would respond to environmental change. Microbial biologists need to learn more about how microbes in lakes assemble into communities, the role of drivers such as competition, predation, resource availability, disturbance, and natural selection in shaping these assemblages. This project addresses the following overarching question: What forces organize microbial communities in humic lakes? Microbes and their communities respond to many forces acting at different spatial and temporal scales, and the effect of these forces can be observed at the level of both communities and populations. An interdisciplinary team of microbiologists, ecologists, engineers, and limnologists will use a suite of molecular tools and genomics to investigate (1) Interactions between bacteria and phytoplankton in the surface layers of lakes; (2) Changes in microbial communities resulting from water column disturbances such as thermal stratification and seasonal mixing and (3) The role of evolutionary processes in shaping individual microbial populations within and among lakes. The results of this work will allow us to better explain and ultimately predict the composition and dynamics of microbial communities and populations in freshwater lakes. This project will not only advance our understanding of the microbial ecology of humic lakes, but of microbial ecology and biodiversity in a broader context. The research approach is structured within an ecological framework and reflect urgent questions in the field of microbial biology. To enhance the broader impacts of the work, the investigators will engage in outreach activities coordinated with the following organizations; the NTL-LTER SchoolYard Science program which promotes inquiry-based learning through workshops for high-school teachers; the Center for Biology Education which is developing a virtual professional development resource for middle and high school science and mathematics teachers; the UW-Madison PEOPLE program which organizes summer courses for underrepresented high-school students; the NSF-funded Center for the Integration of Teaching, Research, and Learning which promotes professional development of graduate students, post-docs, and faculty. The research team will continue to leverage these existing programs to show the general public how freshwater microbes are key components of lake ecosystems, impacting water quality and nutrient cycling in profound ways.