Morphological features and distribution of dinoflagellate cysts in surface sediments from East China Sea and Korean coastal areas

Abstract

Although the morphological characteristics and distribution of dinoflagellate cysts have been widely investigated in many coastal areas of the world, the knowledge&#8212 base in the East China Sea and Korean coastal areas remains limited. To investigate the diversity and distribution of dinoflagellate cysts, surface sediment samples were collected at 27 stations from the East China Sea and Korean coastal areas in June 2015 and May 2017. Cyst morphology was examined with light microscopy and scanning electron microscopy. A total of 21 species belonging to 11 genera dinoflagellate cyst taxa were identified. 5 potentially harmful species were widely distributed: 3 potenti히ly toxic species (Alexandrium tamarense complex, Lingulodinium polyedrum and Protoceratium reticulatum) and 2 potentially bloom&#8212 forming species (Scnppsiella trochoidea and Gonyaulax spinifera complex). The abundances of dinoflagellate cysts ranged from 87 to 993 cysts/g wet weight. Cyst concentrations in the East china sea were relatively higher than in the Korean coastal areas. The organic-walled cysts were dominated by Spiniferites spp. ( Gonyaulax spinifera complex) and Brigantedinium spp. (Protoperidinium spp.), and followed by the calcareous-walled cysts were dominated by Leonella granifera and 1horacospharera sp. 171 To investigate the diversity and distribution of dinoflagellate cysts, surface sediment samples were collected at 27 stations from the East China Sea and Korean coastal areas in June 2015 and May 2017. Cyst morphology was examined with light microscopy and scanning electron microscopy. A total of 21 species belonging to 11 genera dinoflagellate cyst taxa were identified. 5 potentially harmful species were widely distributed: 3 potenti히ly toxic species (Alexandrium tamarense complex, Lingulodinium polyedrum and Protoceratium reticulatum) and 2 potentially bloom&#8212 forming species (Scnppsiella trochoidea and Gonyaulax spinifera complex). The abundances of dinoflagellate cysts ranged from 87 to 993 cysts/g wet weight. Cyst concentrations in the East china sea were relatively higher than in the Korean coastal areas. The organic-walled cysts were dominated by Spiniferites spp. ( Gonyaulax spinifera complex) and Brigantedinium spp. (Protoperidinium spp.), and followed by the calcareous-walled cysts were dominated by Leonella granifera and 1horacospharera sp. 171