Experimental evidence for the desynchronization of ecosystem dynamics by global change

Understanding the coordinated response of ecosystems is fundamental to
better apprehend ecosystem dynamics under environmental changes. Here, we
conducted two independent mesocosms experiments to study how warming,
nutrient enrichment, predator overexploitation, and their combination
desynchronize freshwater ecosystems by studying high-frequency
measurements of oxygen dynamics and of their cyclicity at different time
scales (sub-daily to monthly). Nutrient enrichment desynchronized the
whole dynamic of oxygen relative to control mesocosms and desynchronized
oxygen cycles at all time scales, likely due to its effect on primary
production. Warming and overexploitation only desynchronized oxygen
cycles, especially at short-term, reflecting alteration of the diel rhythm
of oxygen dynamic. Lastly, the combination of nutrient enrichment and
warming dampened desynchronization, whereas the effects of nutrient
enrichment were accentuated when combined with overexploitation. This
first empirical evidence of global change impact on ecosystem synchrony
opens important avenues to identify the destabilizing mechanisms of
ecosystem functioning at uninvestigated spatio-temporal scales.