1. Department of Marine, Earth, and Atmospheric Sciences, North Carolina State University, Raleigh 27695-8201, North Carolina, United States
2. U.S. Environmental Protection Agency, Research Triangle Park, Raleigh, North Carolina 27711, United States
3. Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh 27695-8201, North Carolina, United States
4. Conservation and Survey Division—School of Natural Resources, University of Nebraska-Lincoln, Lincoln 68583, Nebraska, United States