Biodiversity of the "Karang Jeruk" Coral Reef Ecosystem in Tegal Regency, Central Java, Indonesia

"Karang Jeruk" is a Fish Sanctuary whose existence is expected to provide protection for the biota in it. The purpose of this study was to collect and conduct baseline analyzes of the condition of coral reef ecosystem. The results for the ecological index are the Diversity Index (H') is 1.7362 (depth 3 m) and 1.8382 (depth 10 m), so that the diversity is moderate with moderate ecological pressure. Uniformity Index (E) is 0.7864 (3 m depth) and 1.0362 (10 m depth) so that it is included in the high population uniformity category. Simpson Dominance Index (C) is 0.2405 (3 m depth) and 0.2211 (10 m depth), including the species dominance category is low. The percentage of coral cover is 1.30%-69.28% in the damaged to good category. Diversity Index data (H') is 1.5157 (3 m depth) and 1.3896 (10 m depth), so that the diversity is moderate with moderate ecological pressure. Uniformity Index (E) is 0.7062 (3 m depth) and 0.6353 (10 m depth) so that it is included in the high population uniformity category. Simpson Dominance Index (C) is 0.2920 (3 m depth) and 0.3497 (10 m depth), including the species dominance category is low.