His main research interests focus on biogeochemical processes controlling the aqueous chemistry of rivers and the impact of urbanization on the water quality of rivers in the piedmont of the eastern United States.Gregory P. Lewis is an assistant professor of biology at Furman University. He has broad interests in watershed biogeochemistry and linkages between terrestrial and aquatic ecosystems. He has conducted research on influences of forest insect defoliations, forest species composition, wetlands, and man-made impoundments on the nutrient chemistry of streams and rivers in the eastern United States.