Macroinvertebrate assemblage structure was compared from 12 streams differing in urbanization type and degree. Urbanization, both historical and current, was measured using several variables generated from GIS overlays of land cover, aerial photographs, and field exploration in the study watersheds. Quantitative benthic macroinvertebrate samples were taken, and a variety of physicochemical characteristics were measured. Increasing urbanization resulted in a decline in diversity and abundance of intolerant organisms. Streams in industrial areas had greater invertebrate density due to large increases in a few tolerant groups. Urbanization in the watersheds was coupled with changes in the physical and chemical structure of the streams suggesting some possible mechanisms for urbanization impact on stream biota. Multivariate analysis grouped streams based on a number of pollution-sensitive taxa suggesting the utility of this type of approach in analyzing community data.

Primary funding for this project was from the Coweeta Hydrologic Lab NSF-LTER grant. Additional funding was provided through a Graduate Research and Development Project grant from the Graduate Student Assembly of Virginia Polytechnic Institute and State University. Matching funds were provided by the Biology Department.