Meiobenthic community structures on the sediment of seagrass bed and mangrove forest in Chuuk lagoon, Micronesia

Abstract

This study was conducted to investigate the community structure and distributional pattern of meiobenthos on the sediment of the mangrove forest and seagrass bed in the Chuuk lagoon. The samples were collected by an acryl corer at 14 stations. Nematodes were the most abundant meiobenthos, followed by ciliophorans and polychaetes; these taxa comprised more than 70% of the total abundance at all stations. The meiofauna sampled in seagrass bed were more diverse than those of mangrove substrates. Total densities were higher in mangrove stations than other sites, averaging 1,671 to 2,967 inds./10 cm2. Densities in seagrass area ranged between 605 and 1,053 inds./10 cm2. Biomasses, however, were higher in seagrass bed (975-2,167 μg free dry weight/10 cm2) than in mangrove area (1,064-1,180 μg free dry weight/10 cm2). Ordination chart by MDS of major meiofaunal density in each station showed difference between mangrove area and seagrass area in terms of habitat of meiobenthos.