My background and training are in physics and biogeochemical cycling, with particular focus on climatic controls on trace gas emissions from terrestrial ecosystems. My current research focuses on the interactions between terrestrial ecosystems, human land and water use, and the Earth's climate system. Specific research interests include: contemporary carbon balance and long-term carbon accumulation in peatlands; regional and global agricultural land and water use; greenhouse gas fluxes from agricultural systems; carbon and nitrogen biogeochemistry; permafrost; and microwave remote sensing of tropical forests and urban areas.