Sequential stressor mesocosm experiment - fish x warming

Cumulative impacts of multiple extreme and novel environmental changes on communities are often the result of asynchronous rather than simultaneous exposures to such stressors. Yet, the importance of temporal dynamics remains a major knowledge gap in multiple stressor ecology, lacking theory or evidence. We provide a conceptual template for predicting the ecological importance of the order in which consecutive stressors occur (i.e. an exposure order effect) based on correlated species responses. Negative correlation of species responses is hypothesized to increase, while positive correlation is expected to reduce, exposure order effects of consecutive stressors on communities. Towards a proof of concept, we experimentally exposed planktonic communities from fishless mountain lakes to different temporal sequences of two stressors, namely invasive sportfish and elevated water temperatures. Both stressors suppressed the same resident top predator and large grazers while eliciting positive ...