Assessing Impacts of Urban Expansion on Coastal Ecosystems Based on Different Growth Scenarios

Abstract

Urban expansion and associated land use change have complex effects on ecosystems. Some effects have not been felt or perceived as being severe as of now, but they might become detrimental in the future if the trend continues. Predictive modeling allows us to anticipate if this is the case and to take action if necessary. This study combines the products of simulated urban growth and the U.S. Geological Survey's gap analysis to assess potential ecological impacts of future urban expansion on vegetation cover, habitats, and biodiversity. Five growth scenarios were used to implicitly simulate urban expansion from 2000 through 2030 at different growth rates, urbanization extents, and sprawl areas. As found in the Beaufort area in South Carolina, substantial losses of vegetation cover and habitat areas for four selected species, particularly local common species, are forecast even under the most conservative scenario. Although urban residential areas have a greater number of species than the average in all land areas, predicted continuous shrinking of the habitats of enlisted endangered species is worthy of concern. Although the approach and methods used here are applicable in other regions as a diagnostic tool for impact assessment, maps and tables generated are useful for visualizing spatiotemporal changes and for making decisions in land use planning and coastal ecosystem management.