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Ellen Prager (no longer with USGS)
Halley, R. B.
Hall, M., Hall, J.
Fourqurean, J. W., Iverson, R. L.
The site surveys and boat transects were compared with aerial photographs from December 1994 - January 1995 and SPOT satellite imagery from 1987 to produce the map of bottom types for Florida Bay. The map of bottom types was created using CPS3 (Contour Plotting System software) and ArcInfo 7.0.3.
The data were reprojected from UTM ZONE 17, NAD83 to GEOGRAPHIC, NAD83 for SUDS 5/20/02.
The map was created using CPS3 (Contour Plotting System software), ArcInfo7, and AMLs. The coverage was converted to a shapefile to be used on ArcView applications.
Descriptions: The description of the sediment data and use of ArcView assumes the reader has limited knowledge of ArcView 3.2.
sed.apr is a project file that might come in handy to quickly look at the data. Edit the .apr file and search for the pathnames for newsed4 and sedpts97. Change the file names to where the data files are stored.
The sed.avl file contains the shade set for the sed data. In ArcView, add the newsed4 theme, and then bring up the legend editor, legend type-unique value, values field - sedname. Then 'load' the sed.avl, and it will look like the map that Ellen Prager produced.
There is also a layout of the map that looks like what she published (although this layout was recreated for the web site). The newsed.ps postscript file is 8.5 X 11 inches. Or desired portions can be printed from the layout.
Problems bringing this in to Adobe Illustrator to print it were corrected by just changing the mudbank color (removing the stippling) in ArcView.
Bank Top Suite - commonly called mud banks and occurring at depths typically less the 0.6 m. These areas are spatially complex environments that are dominated by mud, sand, or, in the western portion of the Bay, gravel.
Open Mud - areas where no significant seagrass growth occurs and other benthic fauna except for algal mats are not apparent. Sediments are predominately carbonate mud with a relatively high organic and water content.
Hardbottom - areas with little or no seagrass cover and only up to 5 cm of sediment overlying the Pleistocene limestone bedrock. Sediments tend to be either lightly muddy carbonate sand or sand, have relatively little organic matter, and low water content.
Sparse Seagrass Cover - area in which greater than 50 percent of the bottom is exposed. Sediments are predominately slightly muddy carbonate sand, sandy mud, or sand and vary form 3 cm to over 2 m in thickness.
Intermediate Seagrass Cover - greater than 50 percent seagrass cover with open areas of exposed sediment on the bottom less that 50 percent. Sediments are dominated by sand and shelly (gravely) carbonate mud from 0.33 m to over 2m thick.
Dense Seagrass Cover - areas where the bottom is completely obscured from view by grass growth. Sediments are muddy sand with a relatively high organic and/or shell content.
Open Sandy Areas - areas that are distinct from hardbottoms in that no significant benthic life is present. Sediments are coarse shelly carbonate sands.
Mixed Bottom Suites - areas of a highly variable bottom type where variations in seagrass density are extreme and open mud areas occur on a seemingly irregular basis. Sediments are coarse shelly carbonate sands.
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