Characteristics of meiofaunal communities inhabiting waters surrounding marine research stations based in the Yellow Sea and East China Sea

Abstract

This study aimed to analyze meiofaunal communities near three marine research stations (MRSs) installed in the Yellow Sea to identify the characteristics of meiofaunal communities in subtidal zones. The study was conducted using samples collected near Ieodo MRS (I-MRS), Gageocho MRS (G-MRS), and Socheongcho MRS (S-MRS) located on the southern, central, and northern parts of the Yellow Sea, respectively. The average distribution density of meiofauna was 118.9 ± 11.1 Inds./10 cm² in 2016 and 237.4 ± 33.7 Inds./10 cm² in 2020 near I-MRS; 65.9 ± 12.5 Inds./10 cm² in 2017 near G-MRS; and 196.9 ± 32.8 Inds./10 cm² in 2018 and 392.5 ± 41.8 Inds./10 cm² in 2019 near S-MRS. The range of these abundances is similar to those observed in the subtidal zones of the Yellow Sea. The results showed that the distribution density of meiofauna was high near the S-MRS but low near the G-MRS, which had fine-grained sediments and higher TOC content than the other MRSs. The mean number of meiofaunal taxa observed was 6.9 in 2016 and 8.9 in 2020 near I-MRS; 5.4 in 2017 near G-MRS; 8.8 in 2018 and 9.5 in 2019 near S-MRS. The G-MRS region, characterized by fine sediment, had the highest proportion of nematodes, the lowest abundance of harpacticoids among all MRS regions. Also the analysis of meiofaunal abundance by size revealed that there are higher and lower proportions of small-sized and large-sized meiofaunal individuals than the other MRS areas. A cluster analysis confirmed that the meiofaunal communities form distinct groups based on the locations of the MRSs. Correlation analysis between sediment environmental factors and distribution density of meiofauna revealed a significant negative correlation between sediment grain size and TOC content.