Cost-benefit analysis of protection forests and their ecosystem services: a Scoping review

Among the many ecosystem services provided by forests, including raw material production, climate regulation, biodiversity and recreation, protection against gravitational natural hazards is particularly important in mountain regions. In Switzerland, protection forests represent approximately half of the total forest cover, and constitute a valuable and cost-effective nature-based solution. Yet, this protective function, alongside other forest ecosystem services, is rarely assessed (i.e., quantification, economic valuation) in a systematic and comparable manner. Therefore, our study aims to establish the state of the art regarding cost-benefit analyses (CBAs) of mountain protection forests and their ecosystem services, through a scoping review across N=5 databases and N=35 peer-reviewed publications and grey literature.

Results confirm the primary role of mountain forests in regulating gravitational hazards, particularly rockfalls and avalanches. Most importantly, this review highlights a significant lack of comprehensive CBAs addressing mountain protection forests and associated ecosystem services. Indeed, studies tend to rely on partial or service-specific economic assessments, often disregarding other beneficial forest functions. Moreover, external drivers such as climate change and forest disturbances (e.g., windthrow, insect and pest outbreaks, wildfires) are often neglected in existing literature, although they may influence the provision of ecosystem services.

Finally, despite the absence of a standardized methodology, largely due to variability in site conditions, CBAs remain a valuable tool for decision-makers in sustainable forest management, land-use planning, climate adaptation, and natural hazard mitigation.