The mangrove, seagrass, and coral reef ecosystems in Panitian (Quezon) and Punta Baja (Rizal), Southern Palawan, Philippines, were assessed to examine community structure, biodiversity patterns, and ecosystem condition across linked coastal habitats. Mangrove forests remain extensive, with each municipality supporting over 2,000 hectares and approximately 50 percent (12–13 species) of Palawan's documented mangrove species. The mangrove canopy structure and mature stands are largely intact; however, species diversity (H′: ~0.4–2.0) and regeneration rates are low. Seagrass assessments indicated higher species richness and cover in Punta Baja (nine species) compared to Panitian (six species), although both sites exhibited moderate to poor ecological conditions. Coral reef surveys revealed ongoing degradation, characterized by low coral taxonomic richness (12–17 TAUs) and reduced hard coral cover. A total of 113 reef-associated fish species were recorded, yet overall fish density was low and reef-associated invertebrates were limited in abundance. Anthropogenic activities, including coastal development, resource extraction, and habitat conversion, continue to adversely impact these ecosystems. Nevertheless, all three ecosystems maintain considerable ecological and economic value. Enhancing the condition of these resources necessitates an integrated coastal management strategy, encompassing strengthened protection, habitat restoration, and the establishment or expansion of marine protected areas.
Keywords: Coastal Marine Ecosystem, Coastal Ecosystem Assessment, Community Structure, Anthropogenic Impacts, Biodiversity Patterns