Actors' diversity and the resilience of social-ecological systems to global change

Biological diversity is known to enhance the resilience of ecosystems to environmental change. It is, however, unclear whether a high diversity of social actors analogously increases the capacity of social-ecological systems to maintain the provision of ecosystem services while undergoing socio-economic and climate changes. Here, using an empirically informed agent-based modelling approach, we demonstrate that both the number of actors (actors richness) and the diversity of the abilities and skills that characterize their management capabilities (actors' functional diversity) are key determinants of the resilience of social-ecological systems to global change. A high complementarity of the actors' functional diversity helps to buffer vulnerable mountain systems against socio-economic and climate change. Actors' response diversity can mediate an abrupt shift in the social-ecological system, leading to new trade-offs in ecosystem services. Our results highlight the importance of considering both the diversity and the complementarity of actors' management capabilities to ensure the provision of ecosystem services in the face of uncertain global change.