Simultaneous synergist, antagonistic and additive interactions between multiple local stressors all degrade algal turf communities on coral reefs

摘要

1. Ecological communities are subjected to multiple anthropogenic stressors at both global and local scales that are increasing in number and magnitude. Stressors can interact in complex ways and are classified as additive, synergistic or antagonistic; the nature of the interaction is key to predicting changes and understanding community resilience. Coral reefs are among the most impacted communities and have shifted from coral-to algal-dominated states, and overfishing, nutrient enrichment and sedimentation are local stressors that often co-occur and may support degraded algal states. Short algal turfs are abundant benthic space holders on healthy reefs that may be pushed by local stressors to long algal turfs, a more degraded state that may prevent recovery to coral dominance.