Polychaete Assemblages in the Sungai Terengganu Estuary (East Coast of Peninsular Malaysia): Spatial Distribution Patterns

Urban developments in estuarine areas affect benthic organisms, notably the macrobenthos, by physically modifying the territory and generating waste. The polychaete assemblages and the environmental parameters in the estuarine area of Sungai Terengganu were examined based on nine stations along a salinity gradient from oligohaline to polyhaline. Samples were collected using a Smith McIntyre grab and yielded 1886 individuals, from 43 species grouped into 24 families. The fauna was mainly dominated by Composetia sp. (39.48%) and Cossura sp. (31.87%); the former in oligohaline areas and the latter in the polyhaline areas. The densities of both species had significant positive correlations with salinity, temperature, and silt, clay, and gravel contents. This study will benchmark the polychaete community distribution in this tropical estuary, which could be similar to environments along the east coast of Peninsular Malaysia (South China Sea).