Kelimpahan epifit sebagai indikator dalam indeks ekologi kesehatan lamun: studi kasus Pantai Sanur Bali

Seagrass ecosystems are essential components of tropical coastal environments, providing critical services such as carbon sequestration, shoreline protection, and habitat for marine biodiversity. In Indonesia, these ecosystems face increasing threats from anthropogenic activities, particularly in tourism-heavy regions like Sanur, Bali. While numerous studies have assessed seagrass cover, limited attention has been paid to the role of epiphytic communities as indicators of environmental health. This research addresses this gap by evaluating the ecological health of seagrass meadows through the Seagrass Ecological Quality Index (SEQI) and epiphyte structure across five sites in Sanur. The study aimed to determine how variations in seagrass and epiphyte characteristics reflect broader ecosystem conditions under different environmental pressures. Using a transect-quadrat method, data were collected on seagrass species richness, cover, water clarity, and the percent cover of macroalgae and epiphytes. Epiphytes were microscopically identified and classified. The findings reveal that Thalassia hemprichii, Enhalus acoroides, and Halophila ovalis dominate the region. SEQI scores ranged from 0.5669 to 0.6636, categorizing all sites as having moderate ecological condition. Bacillariophyceae dominance in Samuh reflects healthier conditions, while Cyanophyceae prevalence in other sites indicates eutrophication. This study highlights the utility of seagrass–epiphyte associations as sensitive bioindicators of ecosystem quality. The integration of SEQI and epiphyte analysis provides a cost-effective, scalable approach for monitoring shallow marine environments. These insights contribute to ecosystem-based management strategies vital for the conservation and restoration of coastal habitats in Indonesia.