The ecosystem service transition in mountain socio-ecosystems

Land use is one of the main drivers of ecosystem service provision. The forest transition theory has provided a productive framework for the analysis of land use dynamics worldwide, based on development trajectories leading from contraction to expansion of national or regional forest area. We propose that a similar generic framework can be developed to analyze and predict changes in the delivery of multiple ecosystem services, going beyond the simple consideration of changes in area of different land cover types to consider changes in their qualities in terms of ecosystem service supply. This framework depicts trajectories of provisioning, regulating and cultural services, and the resulting trade-offs when moving from agrarian societies focused on self-sufficiency to resource-extraction economies and amenity seeking societies. We illustrate the framework in the case of mountain socio-ecological systems, as key multifunctional systems which have undergone and are expected to undergo large changes in land use and ecosystem services as a result of global change. The analysis of case studies selected to picture the global diversity of mountain socio-ecological systems reveals how the interplay between ecological constraints and changes in demand as a result of societal change and specific policy instruments underpins past, current and expected ecosystem services. Finally we discuss expected impacts of drivers of global change such as climate or policy, and how the framework can be applied to understand transformations of mountain coupled human-environment systems. (Résumé d'auteur