Dr. Erle Ellis is Associate Professor of Geography and Environmental Systems at the University of Maryland, Baltimore County, where he teaches Environmental Science, Landscape Ecology and Biogeochemistry. His research focuses on ecological processes in anthropogenic landscapes at local, regional and global scales, and their transformation by population growth and industrially-based technologies. He has studied long-term changes in nitrogen balance in village ecosystems of China's Tai Lake Region, and changes in the biogeochemistry of carbon, nitrogen and phosphorus across the densely populated agricultural village landscapes of China. He is also working to improve global models of human interactions with terrestrial ecosystems. Dr. Ellis holds an A.B. in Biology (1986) and a Ph.D. in Plant Biology (1990) from Cornell University.