Authors: Jessica Morgan*, , Yeqiao Wang, University of Rhode Island, Naomi Detenbeck, U.S. EPA
Topics: Water Resources and Hydrology, Urban Geography, Spatial Analysis & Modeling
Keywords: Impervious Cover, Riparian Zone, High Spatial Resolution Data, Vermont
Session Type: Paper
Start / End Time: 10:00 AM / 11:40 AM
Room: Lafayette, Marriott, River Tower Elevators, 41st Floor
Presentation File: No File Uploaded
Impervious cover (IC) is a known stressor on stream ecosystems and vegetated riparian areas can help to mitigate some of the impacts of urbanization. However, analyses of the effects of riparian zone IC on water quality may be limited by the spatial resolution of IC data as well as by the methods used to quantify IC within those riparian areas. We compared IC estimates in riparian zones of Vermont using two different spatial resolutions of IC data and two methods of buffer delineation. Percent IC was obtained from the 2011 National Land Cover Database (NLCD) and compared to a high resolution imagery analysis from 2011 National Agriculture Imagery Program data within the riparian zones. Fixed-width (120m) and elevation based riparian buffers were delineated in ArcGIS. Although previous research suggests that spatial resolution affects IC estimation in full catchments, this study found less of an effect within the riparian zone in the same geographic areas. Buffer type had minimal impact on IC calculations, except in areas of unconstrained valleys, where there were notable differences between fixed-width and elevation based buffers for both NLCD and high resolution imagery. Our results suggest that NLCD IC estimates may be adequate for mapping IC in the riparian zone for water quality studies. However, geomorphic differences in valley type must be considered when choosing the spatial resolution of land use data for IC analysis.