Temperature Driven Decoupling of Carbon Cycling in Freshwater Sediments and the Relative Production and Flux of Methane Versus Carbon Dioxide

点击翻译按钮获取中文摘要

Methane is an atmospheric greenhouse gas that is an integral part of the global carbon cycle. Much of the methane is produced biologically, and globally, between 20-40% of the annual methane transfer to the atmosphere originates from freshwater wetland sediments. However, critical aspects of the factors regulating methane production and release from freshwater wetlands remain poorly understood. This work will examine methane dynamics within the context of the sediment carbon cycle at sites in Florida, Georgia and Massachusetts. The investigators will evaluate how temperature, an important aspect of modern global change, organic carbon availability and microbial populations interact to regulate breakdown of complex organic matter and production of methane. The research program emphasizes field sampling and laboratory experimentation and is organized around the working hypothesis that changes in temperature influence the rate and efficiency of organic carbon breakdown and the production of methane in freshwater sediments. As a greenhouse gas, methane is over twenty times as effective as carbon dioxide in trapping heat in the atmosphere. Thus, understanding the factors that control methane production is critical to understanding and predicting climate change. This project will advance our understanding of methane cycling in freshwater habitats, and will complement and expand the carbon cycling component of on-going long-term ecological research studies in Florida, Georgia and Massachusetts. It combines an interdisciplinary field program with modeling and will involve postdoctoral, graduate and undergraduate students, including members of underrepresented minority groups.