Plant Controls of Terrestrial Trace Gas Fluxes: Legumes, Microbes, CO and Hydrogen

University Of Maine, Orono ME

Investigators

Abstract

This research seeks to determine the role of plant-microbe interactions on the production and fate of key trace gases in the atmosphere, particularly carbon monoxide (CO) and hydrogen (H2). Recent observations have revealed that the roots of all plants produce CO, and that the roots of nitrogen-fixing plants (Fabacae, commonly legumes) produce large amounts of both CO and H2. Production of these gases provides the basis for an interaction of plant roots with soil microbes that oxidize CO and H2. Field and greenhouse studies will involve a variety of cultivated and non-cultivated legumes and other plant taxa. Experimental analyses will include measurements of gas exchange in situ, measurements of root gas production, isolation and characterization of trace-gas utilizing microbes, and applications of molecular techniques based on the use of 16S rRNA and rubisco genes. The research will lead to insights about the controls of atmospheric trace gas composition and the impacts of land use and agricultural practices.