Characteristics of corals spectral from different species are expected have optically different characters. This study classified the dominant substrate of shallow water base on spatial resolution of imagery and in situ measurement and analyzed the accuration of Landsat 8 OLI_TIRS and Sentinel-2A satellite imagery to determine health of coral reefs. The image processing are atmospheric correction, cropping, masking, Depth Invariant Index, Unsupervised classification, ground truthing, reclassify, accuracy assessment, and spectral reflectance analysis. Unsupervised classification used IsoData method with Lyzenga application to detection of coral reefs condition. Spectral measurement by spectroradiometer underwater, photo underwater, and geotagging are conduct as in situ measurement. Spectral reflectance of medium spatial resolution image and in-situ measurement are integrated to discriminate of live coral, dead coral cover with algae, rubble and algae. The results of this study show a baseline for develop the Di gi t a l Coral Health Chart as an approach to determine living coral condition using remote sensing techniques. It can be used as an effective way for detecting and monitoring of dynamic changes of coral reefs on small islands in Spermonde Archipelago. Image analysis integration and in situ survey results show that rubble and dead coral with algae were indicating as coral death due to either damaging human activity and natural death.
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