1. Department of Geographical Sciences, University of Maryland, College Park, MD 20742, USA
2. U.S. Fish and Wildlife Service, National Wetlands Inventory, Falls Church, VA 22041, USA
3. Department of Environmental Science & Technology, University of Maryland, College Park, MD 20742, USA
4. U.S. Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA
5. U.S. Fish and Wildlife Service, National Wetlands Inventory, Madison, WI 53711, USA
6. U.S. National Oceanic and Atmospheric Administration, North Charleston, SC 29405, USA