Collaborative Research: Plant Regulation of Competition Between Methanogens and Iron Reducing Bacteria in Freshwater Wetlands

非技术摘要(提案0516121)标题：合作研究：淡水湿地中产甲烷菌和铁还原细菌之间竞争的植物调节这项工作的目的是加强我们对湿地中影响气候的重要但不可见的过程的理解。我们将研究植物和微生物如何在地下相互作用来调节甲烷的产生，甲烷是一种强大的温室气体，目前占全球变暖的20%。我们怀疑植物、产甲烷细菌(即产甲烷菌)和铁还原细菌之间存在重要的生态相互作用。湿地植物创造微生态位，其广泛的根网络提供有机碳，并将O2引入以缺氧为主的土壤环境。这些植物驱动的因素似乎对微生物群落结构和微生物竞争的结果产生了深远的影响。我们将通过移除植物和/或添加有机基质来操纵淡水湿地，然后跟踪甲烷的产生、铁的还原和其他关键的微生物过程。为了成功地将微生物活动和微生物群落组成的测量联系起来，我们将使用分子技术来追踪在关键生理方面不同的微生物。我们假设甲烷产量的增加将是微生物争夺资源和微生物群落结构变化的结果。这些信息将有助于开发基于过程的湿地温室气体排放模型。

Non-Technical Abstract (Proposal 0516121)Title: Collaborative Research: Plant regulation of competition between methanogens and iron reducing bacteria in freshwater wetlands The purpose of this work is to enhance our understanding of important but 'unseen' processes in wetlands that influence climate. We will examine how plants and microbes interact below ground to regulate the production of methane, a powerful greenhouse gas that currently accounts for 20% of global warming. We suspect that there are important ecological interactions between plants, methane-producing bacteria (i.e. methanogens), and iron-reducing bacteria. Wetland plants create micro-niches in which their extensive root network provides organic carbon and introduces O2 into the predominately anoxic soil environment. These plant-driven factors appear to profoundly influence microbial community structure and the outcome of microbial competition. We will manipulate a freshwater wetland by removing plants and/or adding organic substrates, then track methane production, iron reduction, and other key microbial processes. In order to successfully link measurements of microbial activity and microbial community composition, we will use molecular techniques to track microorganisms that differ in key aspects of their physiology. We hypothesize that increases in methane production will be the result of microbial competition for resources and changes in microbial community structure. This information will help inform the development of process-based models of greenhouse gas emission from wetlands.