Condition of Coral Reef Cover and Water Environment in Karimunjawa and Kemujan Island

Abstract Karimunjawa and Kemujan Islands are the largest islands in the Karimunjawa National Park which have a coral reef ecosystem. Coral reefs are influenced by the environmental conditions around them. Changes in environmental conditions, rising of sea surface temperatures, and human activities can pose threats. Coral reefs have important functions and roles in the balance of marine ecosystems, so monitoring coral reefs is very important. To develop coral reef conservation in the waters of Karimunjawa Island, a study was conducted to monitor the condition of coral reef cover using remote sensing. The purpose of this study was to determine changes around coral reefs in the waters of Karimunjawa Island and Kemujan Island in 2018 using Landsat 8 satellite imagery and to analyze changes in the area and condition of coral reefs in the waters of Karimunjawa Island and Kemujan Island, Karimunjawa National Park. This study uses a remote sensing method which begins with collecting Landsat 8 satellite imagery data, then continued with satellite image data processing with ENVI and ArcGIS 10.8 software using the Lyzenga algorithm for coral reef mapping. This method is more efficient and can cover a wide study area.