Phytoplankton community organization and succession by sea warming: A case study in thermal discharge area of the northern coastal seawater of China

Thermal discharges from power plants elevate temperatures in the surrounding waters, and this warming of the marine environment inevitably influences phytoplankton communities. In this study, we conducted seasonal sampling in coastal waters of the Bohai Sea off Qinhuangdao, China. The results revealed that the coastal waters are notably affected by thermal discharge, with unseasonably-high water temperatures, particularly during winter. The change of phytoplankton community structure has been detected in the warmer coastal seawater. Although diatoms were the dominant species during field investigations, there were no significant seasonal changes in diatom abundance. In contrast, the density of dinoflagellates was low in all seasons due to the effects of thermal discharge. Consequently, the general trend in phytoplankton succession was interrupted. In general, the findings of this study may provide further insights into the warmer environmental impacts on phytoplankton communities in temperate regions.