Characteristics of meiofaunal community in the subtidal zone near Hupo, anticipating ocean acidification in the East Sea of Korea

Abstract

This study aimed to investigate the meiofauna community characteristics in coastal waters highly affected by ocean acidification. Therefore, the meiofauna communities in the coastal waters of Hupo in Uljin-gun, a county bordering the East Sea of Korea, were monitored over five years. During the study period, the mean abundance of total meiofauna communities expressed in population density was 614.4 individuals (Inds.)/10 cm2, similar to the reported meiofauna abundance in the subtidal zone in the Yellow Sea of Korea, an area with sandy sedimentary facies. The most dominant taxa were nematodes (65–70%) and harpacticoids (7–20%); these two taxa accounted for approximately 80% of the total meiofauna abundance. Among the stations studied, station (St.) 10 showed the lowest seawater pH value, and in 2011, when the measured pH was the lowest at 7.82, St. 10 showed the lowest abundance values for total meiofauna and harpacticoids in the 5-year period. To examine the effect of ocean acidification on meiofauna communities at the species level, species of nematodes, the most dominant taxon, were analyzed. The results indicated that the number of nematode species at St. 10 in 2009, when the pH value was low, was 8, which was very low compared to that in the other years of the study period. According to the feeding type, epistrate feeders (2A) accounted for a remarkably high proportion at St. 10, which showed a low pH. This study provides various data on meiobenthic community characteristics to understand the effects of ocean acidification on coastal ecosystems.