Evaluation of Error Reduction Techniques on a LIDAR- Derived Salt Marsh Digital Elevation Model

McClure, A.; Liu, X.-H.; Hines, E., and Ferner, M.C., 0000. Evaluation of error reduction techniques on a LIDAR-derived salt marsh digital elevation model. Journal of Coastal Research, 00(0), 000–000. Coconut Creek (Florida), ISSN 07490208. Accurate elevation information is a necessity for conservation and management of tidal salt marshes where elevation differences can be as little as 2 m and where sea-level rise is a critical threat. We applied an existing method to evaluate and improve the vertical accuracy of a 1-m LIDAR-derived digital elevation model (DEM) using a real-time kinematic (RTK) GPS dataset with a vertical accuracy of 60.02 m and local vegetation data within a tidal salt marsh. We generated correction factors for vegetation species within each major vegetation class and produced a modified DEM of the site. Comparison between the original and modified DEM showed that the mean error was reduced from 0.16 m to 0.004 m and the root mean squared error was reduced from 0.212 m to 0.098 m. These results demonstrate that it is possible to significantly reduce vertical error contained within a salt marsh DEM derived from a LIDAR dataset using highly accurate RTK GPS data combined with vegetation data collected on a per site basis. ADDITONAL INDEX WORDS: DEM, China Camp State Park, National Estuarine Research Reserve, coastal vegetation, sea-level rise.