Interannual variation in zooplankton communities around a nuclear power plant and their relationships with thermal effluent in summer

To evaluate the effects of the thermal effluent from the Hongyanhe Nuclear Power Plant on zooplankton communities in the surrounding sea area, the distribution and structure of zooplankton communities in Liaodong Bay were investigated in the summer from 2017 to 2020. Zooplankton community diversity, abundance, and structure were evaluated at 11 stations near the Hongyanhe Nuclear Power Plant alongside zooplankton-environment relationships on the basis of measurements of seawater temperature, salinity, and chlorophyll a concentration. Significant interannual changes in zooplankton communities associated with the thermal effluent from the power plant were observed. Variation in species dominance, particularly that of Calanus sinicus, Acartia bifilosa, and the blooming Noctiluca scintillans, altered the zooplankton community structure across the four years. These results suggest that the thermal effluent from the nuclear power plant could influence and alter zooplankton community structure to some extent. However, global climate change also more strongly influenced zooplankton communities at a broader spatial scale during the summers of 2017-2020.