Warming and thermal extremes like heatwaves brought on by global climate change are nowadays more perceptible than ever. It is undoubtful that these environmental changes will have impacts on Earth in the long- and short-term, including freshwater ecosystems. Despite past research efforts to understand the effects of temperature on aquatic biota, knowledge on how freshwater ecosystems will respond to the future thermal alterations of elevated temperatures and heatwaves, single and in combination with other anthropogenic stressors, such as pesticides, remains limited.

This thesis investigated the multiple stressor effects of stress posed by two different climate change-related temperature scenarios (i.e. elevated temperatures and heatwaves) and pesticides (i.e. imidacloprid and carbendazim) on shallow freshwaters. To better comprehend the mechanisms that drive the observed effects across spatial and biological scales, environmentally and ecologically realistic experiments are useful tools that provide valuable knowledge for chemical risk assessment and ecosystem management towards climate change.