Diversity and distribution of macrozoobenthos in Bojonegara coastal waters, Banten Bay, Indonesia

Coastal ecosystems, essential for ecological stability, face escalating degradation from pollution and habitat loss. Bojonegara waters in Banten Bay experience anthropogenic pressure that may alter benthic communities. This study examined macrozoobenthos diversity, distribution, and relationships with environmental parameters. Sampling employed a van Veen grab across five periods (January, February, August, and October 2020), with concurrent in-situ and laboratory measurements of physical- chemical parameters. Analyses included genus composition, density, diversity, evenness, and dominance indices, as well as Principal Component Analysis (PCA) and similarity indices. Seventy-seven genera from six phyla and eight classes were recorded, dominated by Gastropoda (37 genera), Bivalvia (18), and Polychaeta (12). The highest macrozoobenthic density occurred at Station 3, the lowest at Station 6. Diversity (0.905–2.640), evenness (0.441–0.772), and dominance (0.260–0.659) indices indicated that the Bojonegara waters were at a low to moderate level of pollution. PCA revealed strong associations between Bivalvia, Gastropoda, and Sipuncula with salinity and water transparency variations. Gastropods and polychaetes predominated in estuarine-freshwater substrates, while bivalves thrived in marine substrates. Findings confirm macrozoobenthos as reliable bioindicators for evaluating ecological status and environmental quality in coastal ecosystems.