Macrobenthos community on the intertidal at Garolim Bay in summer

Abstract

Aim: The present study was performed to understand the macrobenthic community in 49 stations of intertidal at Garolim Bay during summer. Methodology: The surface layer sediments and macrobenthos were collected by using the methods employed for the study conducted by Shin et al. (2004) to compare changes in the community of macrobenthos and components of the sediment in the intertidal at Garolim Bay. The improved model of Van Veen grab sampler of 0.045 m(2) of its sampling area was used for sampling of surface layer sediments conducted on a ship in June 2015 at 49 stations placed in the intertidal at Garolim Bay. Results: The sediment environment analysis revealed the mean ratio of sand at 55.50% followed by 41.72% silt and 2.78% clay, respectively. A total of 120 species of intertidal macrobenthos with a density of 630 individuals m(-2) were investigated. The mean biomass thereof was 22.59 g wwt m(-2). The most dominant species was polychaetes, Heteromastus filiformis (68.58%), Mediomastus californiensis (9.43%), crustaceans Ilyoplax pingi, crustaceans Macrophthalmus japonicus and so on. After analyzing the correlation coefficient between biotic in and sediment, the abundance and species evenness were found significantly related to environment factors. Interpretation: In this study, six species of polychaete appeared on the top 10 dominant species; and among them, two species of H. filiformis and M. californiensis belonging to Capitellidae were found with 50% habitation density and more than 75% occupancy.