Analysis of Changes in the Area of Coral Reef Cover on Samalona Island, Mariso District, Makassar City, South Sulawesi.

<b>Background and Objective:</b> Coral reefs on Samalona Island have been under pressure both by natural events and by human (anthropogenic) activities, which have caused area degradation. Research on changes in the area of coral reefs is urgently needed. Hence, the objective of this research was to determine changes in the area of coral reefs from 2017, 2020 and 2023 and to determine the percentage of coral reef cover on Samalona Island. <b>Materials and Methods:</b> The method used to determine changes in the area of coral reef is the (unsupervised) method using Sentinel 2-A imagery and processed with ArcMap 10.8 while determining the percentage of coral reef cover (UPT) and processing with CPCe software. <b>Results:</b> From the results of image processing, it was found that changes occur every 3 years, namely 0.22 Ha, while the results of the accuracy test from the results of image interpretation with a ground check were 87.44%. The results of the percentage of coral reef cover obtained at station I, amounted to 6.99%, at station II 20.55% and at station III, 29.39%. The percentage of coral reef cover on Samalona Island in poor condition refers to the Decree of the Minister of State for the Environment No. 4 of 2001 concerning standard criteria for damage to coral reefs. <b>Conclusion:</b> There is a change in the area of coral reefs on Samalona Island which is heading to a damaged or declining condition every three years from 2017, 2020 to 2023.