Multifunctional Mountain Forest Management Evaluating Adaptation Scenarios Under Climate Change In A Forest Landscape In The Eastern Alps

Mountain forests provide essential goods and services for our society. However, climate change impacts and changing demands question the currently practiced management strategies. Adaptive forest management aims for actions to avoid negative consequences from expected climatic conditions and take advantage of the anticipated changes in the ecosystem. The goal of this study was to assess the effects of mountain forest management strategies under climate change, with particular focus on detailed, spatially explicit management plans and analyses of effects on ecosystem services at different spatial scales. The main methodological tool was the forest ecosystem model PICUS v1.5. To assess the validity of the model outputs, it was tested against inventory data and compared against four other ecosystem models in a case study in the Dinaric Mountains, in Slovenia. PICUS was then applied in a second case study in the Eastern Alps, Austria to evaluate current management practices and eight adaptive management alternatives. The simulations included different cutting patterns (patch-, slit- and strip-cuts), harvest intensities, artificial regeneration and sanitary management under six climate scenarios. Outcomes for the catchment were analyzed for the ecosystem services timber production, carbon sequestration, nature conservation and protection against gravitational hazards (rockfall, erosion and snow avalanche release). Results for the model evaluation demonstrated a good performance of PICUS and other individual tree-based models in simulating complex mountain forest ecosystems under management. Results from the studies analyzing currently applied and adaptive management in the application study showed that none of the alternatives was best regarding all ecosystem services. Patch-cut regimes at low intensity level appeared as a well-suited strategy to maintain landscape multifunctionality. Disturbances by the spruce bark beetle pose a major threat to the stability of the spruce-dominated forests in the future. To strengthen the resilience of the forests, increased forest management intensities accompanied by game management activities are required to foster the establishment of other tree species. The occurring trade-offs between ecosystem services demonstrated the potential for targeted planning processes, especially for protection against gravitational hazards and nature conservation areas. A common understanding of ecological processes and the possibilities of their modification through management is vital to adapt mountain forests for the challenges from climate change and complex demands from society.