1. Watershed (basin) boundaries (shapefiles), or hydrological units and their physical and erosion related characteristics; 2. Estimated bathymetry of the shelf derived from Landsat images; potential threat of sediment delivery and land-based sources of pollution to benthic habitats, derived from NOAA's study, the Benthic Habitats of Puerto Rico and the U.S. Virgin Islands; 3. Calculated potential threat of sediment delivery and land-based sources of pollution to benthic habitats; 4. A filtered, Digital Elevation Model (DEM), subset from the U.S. Geological Survey's National Elevation Dataset; 5. Steepest downhill descent for each raster cell calculated by the Slope function in ArcGIS; 6. Relative erosion rate by land cover type 2000 were determined from a table; 7. Relative erosion rate by land cover type 1990 were determined from a table; 8. Erodibility of soils (Kffact) based upon soil composition derived from the SSURGO soils data base; 9. Mean annual precipitation (mm), derived from climate data collected at weather stations from 1990-2000 (NOAA Monthly Surface Data, NCDC); 10. Maximum monthly precipitation, derived from monthly precipitation for all available weather stations in Puerto Rico; 11. Watershed outflow points, (areas of maximum flow accumulation within hydrological basins) calculated from FLOWDIRECTION and FLOWACCUMULATION which were derived from the Digital Elevation Model (DEM); 12. topographic slope for Puerto Rico, derived from the U.S. Geological Survey's National Elevation Dataset using various processing and filtering to improve results; 13. Relative Erosion Potential - 2000 (an indicator of sediment and pollution runoff) derived from USGS National Elevation Dataset, NRCS Soils Database and NOAA Monthly Surface Data; 14. Relative Erosion Potential - 1990 derived from USGS National Elevation Dataset, NRCS Soils Database and NOAA Monthly Surface Data; 15. Potential threat of sediment delivery and land-based sources of pollution to coral ecosystems derived from land cover (LC) database (Created by spectral analysis of consistently orthorectified Landsat Thematic Mapper (TM) imagery), USGS National Elevation Dataset, NRCS Soils Database and NOAA Monthly Surface Data; and 16. Relative vulnerability to erosion - 2000 derived from land cover (LC) database (Created by spectral analysis of consistently orthorectified Landsat Thematic Mapper (TM) imagery), USGS National Elevation Dataset, NRCS Soils Database.
The watershed data were checked for errors - all basin IDs correlate to outflow point IDs, any spatial accuracy is the same as the digital elevation model from USGS. No additional accuracy checks were applicable. For detailed information about each GIS layer see the metadata within the GIS data suite.