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REMOTE SENSING OF SEAGRASS.  E. Zeledon¹, C. Hall². ¹Swarthmore College Swarthmore PA 19081 and ²Dynamac Corporation Mail Code DYN-2 Kennedy Space Center FL 32899.

     The purpose of this research was to perform ground field observations to determine the feasibility of using satellite spectroscopic instrumentation for seagrass observation.  Seagrass is vital to maintain healthy aquatic ecosystems, including fish populations.  However, aerial photography, which is currently used to map seagrass beds, often cannot distinguish between algae and seagrass.  This can result in erroneous seagrass maps that in turn can lead to faulty management decisions.  It was hypothesized that advanced hyperspectral imaging systems could distinguish between various seagrass species and algae.  In this study, a radiometer capable of capturing detailed spectral reflectance was used to determine that various species of seagrasses have different spectral reflectance curves.  This potentially can be used to identify seagrass beds using hyperspectral imagery capable of capturing detailed spectral reflectance curves for every target in the image area.  The first derivative of the spectral curve was used to identify the ideal spectral region for further observation.  It was found that the red region of the visible spectrum at approximately 700 nm provided the most spectral significance between different seagrass species and algae.  This research indicates that the hyperspectral radiometer should be substituted for traditional aerial photography in determining seagrass bed distributions.  NASA funded this research in conjunction with the Spaceflight and Life Sciences Training Program (SLSTP) at the Kennedy Space Center.