Structure of Intertidal Soft-Bottom Benthic Macrofauna of a Continental Island on the Amazon Coast

Aviz, D..; Silva, R.F., and Rosa Filho, J.S., 2024. Structure of intertidal soft-bottom benthic macrofauna of a continental island on the Amazon coast. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 966-970. Charlotte (North Carolina), ISSN 0749-0208. The study characterized the macrobenthic community of the main soft-bottom habitats (mangrove, saltmarsh, unvegetated mudflat, sheltered sandy beach, and sandy exposed beach) on Algodoal-Maiandeua Island (Brazilian Amazon coast). Samples (macrofauna, sediment, and hydrological variables) were collected in the rainy and dry seasons. Annelid were dominant on vegetated bottoms (mangrove and saltmarsh) and on the sheltered beach, while peracarids were the most abundant in the mudflat and exposed beach. Significant changes in community structure occurred between habitats and seasons. In both seasons, density and richness were higher on the mudflat and lower on the sandy beaches. The spatial distribution patterns of the macrofauna were especially related to sediment characteristics and environmental rigidity, while salinity was mainly associated with seasonal variations.