Paper No. JAWRA-11-0025-P of the Journal of the American Water Resources Association (JAWRA). Discussions are open until six months from print publication.
Urban Impacts on Streams are Scale-Dependent With Nonlinear Influences on Their Physical and Biotic Recovery in Vermont, United States†
Article first published online: 28 FEB 2012
© 2012 American Water Resources Association
JAWRA Journal of the American Water Resources Association
Volume 48, Issue 4, pages 679–697, August 2012
How to Cite
Fitzgerald, E. P., Bowden, W. B., Parker, S. P. and Kline, M. L. (2012), Urban Impacts on Streams are Scale-Dependent With Nonlinear Influences on Their Physical and Biotic Recovery in Vermont, United States. JAWRA Journal of the American Water Resources Association, 48: 679–697. doi: 10.1111/j.1752-1688.2012.00639.x
- Issue published online: 1 AUG 2012
- Article first published online: 28 FEB 2012
- Received February 22, 2011; accepted January 4, 2012.
- watershed management;
- fluvial processes;
Fitzgerald, Evan P., William B. Bowden, Samuel P. Parker, and Michael L. Kline, 2012. Urban Impacts on Streams Are Scale-Dependent with Nonlinear Influences on Their Physical and Biotic Recovery in Vermont, United States. Journal of the American Water Resources Association (JAWRA) 48(4): 679-697. DOI: 10.1111/j.1752-1688.2012.00639.x
Abstract: The physical and biological conditions of stream reaches in 16 watersheds within the Lake Champlain Basin of Vermont, United States, were assessed and analyzed for a response to total impervious area (TIA) at multiple spatial scales. Natural gradients (e.g., channel slope) and human impacts to channel boundary conditions (e.g., bank armoring) were considered to ensure a robust test of the Impervious Cover Model for upslope TIA. The response of geomorphic stability and sensitive macroinvertebrates to TIA was nonlinear and significant (p < 0.001), decreasing rapidly at 5% TIA. The effect of urbanization on stream condition was shown to interact significantly with drainage area and channel slope using the analysis of covariance (ANCOVA) (p < 0.05). Hydraulic geometry regressions for urban and rural watersheds and ANCOVA were used to describe a significant watershed scale-dependent response of channel width to urbanization (p = 0.001). The analysis of macroinvertebrate data from reaches in different stages of channel evolution indicated that stable reaches supported greater richness of pollution intolerant species (p < 0.001) and overall taxa richness (p < 0.01) than unstable reaches, and that biotic integrity improves as channels regain stability during their evolution into a state of quasi-equilibrium. We conclude that macroinvertebrate communities can respond positively to channel evolution processes leading to natural channel restabilization.