Meta-analysis of the thermal pollution caused by coastal nuclear power plants and its effects on marine biodiversity

The rise in seawater temperature due to industrial activities is one of the main threats to marine biodiversity. In nuclear power plants, large volumes of water are used for their operation, returning to the ecosystem at higher temperatures. A global meta-analysis was performed to evaluate the thermal effects caused by coastal nuclear power plants on marine organisms. We found 853 articles of which, 99 were included in the qualitative analysis and 75 in the meta-analysis. The meta-analysis showed an increase of 4.38 °C in water temperature near the outfall, and the temperature variation of each study was found to be associated with the power plant latitudes. The main effects on organisms were related to changes in the structure and composition of aquatic communities, with species abundance, distribution, dominance, and density being the most cited ones. Among the affected groups, photosynthesizing microorganisms were the most cited, potentially contributing to shifts in ecosystem dynamics. [Display omitted] •Thermal discharges of nuclear plants caused an increase of 4.38 °C in nearby seawater.•The temperature difference between sites was correlated with power plant latitudes.•38 studies linked temperature as the main factor affecting marine organisms.•Shifts were noted especially in species abundance (14.65 %) and distribution (13.79 %).•Among the affected organisms, photosynthesizing microorganisms were the most cited.