A study on species and abundance of macrobenthos within mangroves vegetation zones in Pengkalan Gelap, Setiu

Abstract

Study on distribution of macrobenthos had been done in mangrove forest at Pengkalan Gelap, Setiu. This study was associated with the project of Petra- UNDP mangrove regeneration community project which supported by the Terengganu State Government and UMT. The main objective of this study was to estimate diversity and distribution of macrobenthos in Pengkalan Gelap, Setiu. Sediment characteristics and environmental factors were the most important factors directly affecting the diversity and density of macrobenthos. There were eight species of macrobenthos that regularly found in Pengkalan Gelap; polychaeta, Olygochaeta, Bivalvia, Gastropoda, Echinodermata, Polyplacophora, Crustacea and others. Highest diversity for macrobenthos was found in station 4 transect 1 (H'=0.9268) with the evenness E' value of 0.4763 and Margalef s richness value of 1.6053 while the lowest diversity index for macrobenthos in Pengkalan Gelap, Setiu were found at station 5 with the average (H'=0.504), evenness E' value of 0.259 and Margalef s richness value of 2.6309. Gastropoda was resulted as the dominant species from phylum mollusca in the study area. Results show that the texture of sediments was coarse sand. These indicated that there was a correlation between total and type of macrobenthos with the size of sediment in the mangrove of Pengkalan Gelap, Setiu.