Abstract

A study of bimonthly variations in community structure of macrobenthos in the intertidal zone was carried out in Kan Maw Island and adjacent areas of Myeik Archipelago during the low tide duration. This research was conducted at eight stations around Kan Maw Ifrom May 2017 to February 2019. For each station, three replicates were taken with a quadrant 30x30cm (to a depth of 30cm) along a transect and sieved with a 1mm mesh size. The macrobenthic biodiversity was represented by 73 species belonging to 42 families under eight major phyla viz. Mollusca(53.4%), Arthropoda(20.6%), Brachiopoda(1.4%), Echinodermata(1.4%), Annelida(19.2%), Hemichordata(1.4%), Coelenterata(1.4%), and Nemertea (1.4%). Three metrics were utilized to estimate diversity: Shannon-Weaver's diversity index (H'), evenness index (E') and Margalef’s richness (D) using univariate analysis. The relationship of abundance and diversity indices (except richness, D) were positively correlated with sediment (silt and clay) but temperature, salinity and sand had a negative correlation during the study period. In addition, macrobenthic groups (except Mollusca, Arthropoda and Annelida) were significantly effected by salinity, temperature and pH, but not by sand (except Cnidaria), clay (except Annelida) and silt (except Cnidaria, Annelida, Mollusca, and Arthropoda).

Keywords

community, correlation, diversity index, macrobenthos, Kan Maw Island, macrobenthic, demersal fishery, intertidal zone, mollusk groups, macrobenthos community