Data from: Counteracting cascades challenge the heterogeneity – stability relationship

Spatial environmental heterogeneity is widely assumed to enhance
ecological stability by promoting refugia, biodiversity, and asynchrony.
Yet, we lack field experiments testing this fundamental relationship and
its underlying mechanisms in naturally assembled multitrophic systems. To
address this gap, we monitored experimental substrates replicating
topographic heterogeneity on a rocky shore over three years. Contrary to
theory, heterogeneity showed no net effect on community stability due to
four counteracting pathways. Heterogeneity increased stability by i)
providing refugia that enhanced population stability and ii) boosting
species richness, which promoted asynchrony. At the same time, it
decreased stability by iii) reducing a dominant non-native species and iv)
suppressing consumers, both of which otherwise stabilised community
composition. These opposing processes cancelled out the
heterogeneity-stability relationship, highlighting the complex and
multi-causal nature of this relationship. We caution against the
assumption that increasing heterogeneity universally enhances stability,
particularly in systems with strong consumer interactions and dominant
species.