Community structure and taxonomic diversity of macrobenthic communities in Merchang lagoon, Malaysia

An estuarine area in the east coast of Peninsula Malaysia, namely Merchang lagoon was selected to conduct the present study on the structural and taxonomic diversities of macrobenthic communities. Samples were collected from 3 stations in four sampling occasions associated with different environmental conditions. Benthic community structures, in particular the abundance and species richness showed a significant difference between stations where station 1 which was characterized by clean sandy sediments recorded the lowest number of individuals and species. Likewise, a significant difference was also recorded between months where November (rainy season) comprised the lowest number of individuals and species. Such trend was however not evidence for the Simpson index and Pielou evenness index. In terms of taxonomic diversity, there was no clear difference recorded in taxonomic distinctness (TD) value between stations as well as between months. The dominance of certain species was the causative factor that contributed to the difference in community composition. In contrast, as the dominant species were not taxonomically different from the other common species recorded in the present study, the absence of these species in station 1 and November did not impose a significant impact on the taxonomic distinctness. A further study that measures the physical characteristics of the area is recommended for a better understanding on how the hydrodynamical changes following rainy season would directly affect the benthic organisms.