A SPATIO-TEMPORAL ANALYSIS OF LAND USE CHANGE AND SINKHOLE DEVELOPMENT IN AN URBANIZING KARST WATERSHED OF WEST VIRGINIA: 1984-2004

While there have been studies dealing with urban growth impacts on watershed hydrology and geomorphology, very little has been done to analyze the spatial character and composition of such growth using remote sensing and geographic information system technology in karst watersheds. The intellectual merit of this research is the creation of a better understanding of these impacts, particularly temporal sinkhole development and change, using a geographic perspective. Karst watersheds are more sensitive to environmental change than typical watersheds because soils are characteristically thin and water has relatively short residence times in underlying aquifers. This research addresses a portion of the Opequon Creek Watershed, an urbanizing karst subwatershed of the Potomac River in West Virginia. Opequon Creek lies approximately 60 miles from both Washington, D.C. and Hagerstown, Maryland and has experienced irregular, urban growth patterns and a subsequent population boom over the last 10 years, while sinkholes have become increasingly prevalent.

LandSat 7 imagery and Digital Orthophoto Quadrangles between 1984-2004 are utilized to quantify land use change, and sinkhole frequency and density within the watershed. Ecognition™ software is used to classify land use and sinkholes temporally via spectral and morphometric analysis. The spatial relationship between these variables is explored using FragStats (McGarigal and Marks, 1995), a spatial analysis program that enables exploration of quantitative data at various scales. Interpretation of the statistical relationship between land use change and sinkhole development offers enormous potential in mitigating negative impacts of urban growth in these sensitive watersheds.