Establishing Baseline Subsurface Light Fields for the Flower Garden Banks National Marine Sancturay

摘要

The Flower Garden Banks National Marine Sanctuary (FGBNMS) consists of three separate areas in the northwestern Gulf of Mexico where salt dome crests rise to within approx. 18-meters of the surface from an outer- continental shelf relief of 100-150-meters, and these geologic features provide a platform for unique coral reef ecosystems. It is known that such ecosystems are sensitive to photon flux variability, and this is particularly the case for Mesophotic Coral Ecosystems (MCE's) that consist of light-dependent corals growing beyond the depth limit of traditional SCUBA surveys. Thus we are combining MODIS and SeaWiFS ocean color data with atmospheric and in-water radiative transfer models, as well as high-resolution ocean circulation models, in order to establish baseline environmental conditions for FGBNMS coral reef communities - with specific emphasis on near-bottom Photosynthetically Available Radiation (PAR). Since the original FGBNMS boundary designation in January 1992, high-resolution multibeam bathymetry surveys have revealed numerous other topographic features in the surrounding region capable of supporting biological communities designated by the FGBNMS managers as critical habitats. It is an additional aim of this research to identify likely locations for specific biological communities where no detailed surveys have been performed.