A multi-sensor comparison for coral reef habitat mapping: A case study using a tropical patch reef environment in Biscayne National Park, Florida

Abstract

Reef scientists continue exploring methods to better characterize the status of coral reefs environments. In that endeavor, an airborne AISA image (1m, 24 bands) was analyzed together with Ikonos (4m, 3 bands), ASTER (15m, 2 bands), and ETM+ (30m, 4 bands) spaceborne data in order to increase the small number of pilot sites (Turk and Caicos, Tahiti) where multi-sensors comparisons are now available. The benefits of atmospheric and water column correction on the accuracy of image classification maps are also assessed. Water-column correction considered both, the empirical Lyzenga’s (1978, 1981) approach and the analytical Maritorena’s (1994) model. The latter model requires pixel-specific depth measurements and information on the characteristics of the water column. Bathymetry was collected using an airborne lidar sensor. AISA products were consistently more accurate than spaceborne products with a maximum accuracy of 93%. Also, water column correction proved to be beneficial by generally improving classification accuracy for the processed scenes. Other trends were revealed.