울릉도 주변 해역에서 식물플랑크톤 종 조성 분포

Abstract

To better understand seasonal variation in phytoplankton community structure in the coastal waters of Ulleung island, 4 research cruises were carried out between February and November 2017. Phytoplankton community structure and ambient seawater physicochemical parameters were examined. The phytoplankton community in the coastal waters of Ulleung island was mainly composed of diatoms and dinoflagellates, with 242 taxa in 70 genera of diatoms and 104 taxa in 26 genera of dinoflagellates. Several species of Chlorophyta, Chrysophyta, and Cyanophyta were also observed. Chain-forming diatoms were the most dominant phytoplankton the group throughout the year, except in summer when dinoflagellates dominated in the coastal waters. Phytoplankton abundance was always higher in coastal than offshore waters, which was mainly determined by availability of nutrient. Prorocentrum dentatum bloom and Chaetoceros debilis bloom were observed in the coastal waters during spring and autumn 2017, respectively. The nutrient N:P ratio, rather than Si:N ratio, played a significant role in the regulation of the phytoplankton community structure and the formation of the spring coastal dinoflagellate bloom in the coastal waters of Ulleung island.ater physicochemical parameters were examined. The phytoplankton community in the coastal waters of Ulleung island was mainly composed of diatoms and dinoflagellates, with 242 taxa in 70 genera of diatoms and 104 taxa in 26 genera of dinoflagellates. Several species of Chlorophyta, Chrysophyta, and Cyanophyta were also observed. Chain-forming diatoms were the most dominant phytoplankton the group throughout the year, except in summer when dinoflagellates dominated in the coastal waters. Phytoplankton abundance was always higher in coastal than offshore waters, which was mainly determined by availability of nutrient. Prorocentrum dentatum bloom and Chaetoceros debilis bloom were observed in the coastal waters during spring and autumn 2017, respectively. The nutrient N:P ratio, rather than Si:N ratio, played a significant role in the regulation of the phytoplankton community structure and the formation of the spring coastal dinoflagellate bloom in the coastal waters of Ulleung island.