Multiple stressor effects of a heatwave and a herbicide on zooplankton communities: Implications of global climate change

Aquatic ecosystems are exposed to pesticides through various pathways such as spray-drift, agricultural runoff, and chemical spills. Understanding the impact of on freshwater requires not only understanding how affect aquatic organisms but also knowledge their interactions with other stressors, those related global climate change. Heatwaves extended periods temperature increase relative climatological mean. They increasing in frequency magnitude pose an emerging threat shallow ecosystems. In this study, we evaluated single combined effects herbicide terbuthylazine a simulated heatwave zooplankton communities using indoor microcosms. Terbuthylazine was applied at environmentally relevant concentration (15 µg/L). The consisted 6°C above control for period 7 days. When individually, increased total abundance by 3 times. exposure led indirect effect community structure, reducing some taxa. combination had no significant community, indicating additive dominated herbicide. interaction between two stressors chlorophyll-a concentrations apparently changed structure phytoplankton which may have benefitted cyanobacteria over green algae. Overall, study shows that non-chemical remains challenging task. Further studies should be conducted improve our mechanistic multiple stressor different levels biological organisation.