Humans impact greater than 75% of the earth’s terrestrial surface with more than 50% of the world population living in urban areas. Compared to most other states, Maine has a small urban footprint, but it is growing. Indeed, 77% of Maine’s population growth in the past decade has occurred outside of existing cities in once smaller towns and rural areas leading to urban and suburban expansion. Because streams integrate landscape processes and are readily degraded by anthropogenic stressors, this has put more stream ecosystems at risk. While restoration and monitoring of urban streams generally requires focusing on both ecosystem structure and function, ecosystem functions are difficult to monitor, and monitoring programs typically focus primarily on structural indicators.
This project focuses on improving our ecological understanding of urban streams and using that knowledge to develop watershed and stream restoration indicators integrating the structural and functional aspects of ecosystem health. We focus on carbon cycling, which is a critical ecosystem process that could serve as meaningful and sensitive indicator. This study relates DOC abundance and composition measured seasonally from the fall of 2010 through the summer of 2011 to existing land cover and monitoring data from the Maine Department of Environmental Protection to evaluate DOC composition as an indicator of watershed urbanization. Regression analysis of these data show that land cover change processes can be observed with DOC composition. Future work will integrate these results with development modeling efforts conducted under the Sustainability Solutions Initiative to develop a tool that can help direct development in a way that reduces the potential for stream degradation. This tool will help non-profit, local, state, and federal agencies monitor the effects of urbanization at a watershed scale and provide a simple measure of function for restoration efforts.