한국 남해와 동중국해 북부해역 표층혼합층 내에서 미세플라스틱의 중형동물플랑크톤에 대한 잠재적 위해성

Abstract

The potential impacts of microplastics to mesozooplankton was surveyed at 27 stations in the surface mixed layer of South Sea of Korea (SSK) and Northern East China Sea (NECS) during August 2016. The samples were collected using bongo net (mesh size: 20011m) and physico-chemical properties were obtained by CTD sensors. The offshore waters were relatively warmer and low-saline (Avg. 30.7°C, 27.4 psu) compared to coastal waters (Avg. 28.6°C, 28.8 psu). The total microplastic abundance ranged from 1.16~22.05 particles/m3, in which the abundance peaked at eastern most station of the study area. Types of microplastics observed were fragment, fiber, paint particles, and film, of which polymer types were polyester, acrylic, epoxy resin, alkyd-resin and polyester-alkyd. Fiber (Avg. 57. 7%) and paint particles (Avg. 39.6%) were ubiquitously dominant. The total mesozooplankton abundance ranged from 778~ 13,728 inds./m3, of which peaked at western most station of the study area. The average dominant taxa groups for all stations were immature copepods (31.9% ), adult copepods (31.9%) and cladocerans (7 .5% ). Cluster analysis of microplastics divided stations into 4 major groups. The dominant microplastics in group-1 were paint particles (66.7%), and dominant mesozooplankton taxonomic groups were copepods (immature and adults 60.0%) followed by appendicularians (20.0%). Group-2, group-3 and group-4 were all dominant in fiber (group-2: 87.7%, group-3: 45.6%, group-4: 50.7%), and copepods (group-2: 70.2%, group-3: 69.1 %, group-4: 54.2%), however next dominant mesozooplankton groups differed, in which group-2 and -3 were cladocerans (group-2: 12.5% group-3: 11 .0%), and group-4 were thaliaceans (9.8%). The ratio of microplastic-to-zooplankton ranged from 0.0001~0.0205 (Avg. 0.0028), in which ratio peaked at two stations of group-4. Above results suggest that numerically dominant fibers and paint particles, which is widely distributed, are likely to be encountered