Environmental autocorrelation, ecological stability, and species response diversity: A proposed multipronged framework to understand their interactions

Understanding how environmental variability affects ecological stability is critical for predicting the ecological consequences of the current climate crisis. Environmental variability encompasses both deterministic (i.e., signal) and stochastic (i.e., noise) components. The frequency of environmental noise is measured as temporal autocorrelation. For air and sea surface temperature, the temporal autocorrelation of environmental noise —its colour, spanning scales from days to multiple years— is becoming increasingly positive (reddening) in many regions of the globe, yet its ecological consequences for natural communities remain unclear. Theoretical and modelling studies suggest that environmental reddening can destabilise communities by prolonging adverse conditions, but can have negligible effects when species partition environmental niches considerably. Therefore, response diversity —the diversity of species responses to shared environmental drivers— can be a key modulator of how environmental autocorrelation affects ecological communities. Two interrelated hypotheses are proposed for rocky intertidal communities. First, environmental reddening generally destabilises communities by amplifying the duration of unfavourable conditions in air and sea surface temperature. Second, response diversity buffers these destabilising effects through species asynchronous dynamics, with responses measured within multi-specific communities (realised responses) exerting a stronger stabilising effect than responses measured in species in isolation (fundamental responses). The mid-shore rocky intertidal communities along the southeast Pacific coast in Chile (30°S–40°S) constitute a suitable system to assess the effects of environmental noise on ecological stability due to their particular biogeographic structure. An integrative research framework combining long-term empirical observations, field manipulative experiments, in silico community simulations, and laboratory ecophysiology provides a unified platform for testing these predictions, with direct relevance for forecasting the ecological consequences of climate change in temperate coastal ecosystems.