Trophic status as a factor in phytoplankton resilience to the toxic effects of zinc oxide nanoparticles
摘要
A study was conducted on the effect of zinc oxide nanoparticles (ZnO NPs) on the structural and functional characteristics of the micro-nanophytoplankton community in the Black Sea under different nutrient conditions. It was found that the intensity and nature of the impact of ZnO NPs on the phytoplankton community are determined by the trophic status of the environment. In the nutrient-enriched sample, 20 µg L-1 of ZnO NPs inhibited algal growth; however, the community demonstrated compensatory capabilities, manifested as a restructuring of the taxonomic structure with an increase in the proportion of tolerant species. A concentration of 40 µg L-1 of ZnO NPs induced a pronounced suppression of physiological processes, critically limiting phytoplankton productivity. Under nutrient deficiency, both tested concentrations of ZnO NPs (20 and 40 µg L-1) caused irreversible suppression of cell division and photosynthetic activity, while exposure to the 40 µg L-1 dose led to the elimination of the algal community. It is shown that the trophic status of the aquatic environment is a critical factor determining the resilience of the phytoplankton community to the toxic effects of zinc oxide nanoparticles. Nutrient deficiency makes the community extremely vulnerable to the toxic effects of ZnO NPs, while high nutrient availability provides the metabolic resources for detoxification and the restoration of phytoplankton photosynthetic activity.