Characteristic distribution and community structure of phytoplankton in the different water masses during early summer of southern sea of Korea

Abstract

To assess the short-term variation of summer phytoplankton community structure in the different water masses of stations on and off the southern coasts of Korea, phytoplankton and environmental factors were monitored from18 to 20 June 2009. According to multidimensional scaling (MDS) and cluster analysis based on the phytoplankton community of each station, the southern sea was divided into two groups. The first group was south-eastern stations of Jeju Island, which is strongly influenced by Kuroshio warm current. The second group was the station of along coastal area of southern sea, which was mainly comprised of Bacillariophyceae and Crytophyceae. Of these stations, on St.13 and 28 was formed a temperature front caused by different hydrological conditions. In particular, nutrients and Chl.a concentration in the two stations were significantly higher compared to those in the other stations, implying that the different water masses have brought phytoplankton population accumulation and triggered the micro-algal growth under the high nutrient concentrations. Our results support that phytoplankton community structure may have been influenced in a short-term scale by different water masses and currents in a broad region of southern sea area of Korea.