1. Ecosystem services (ES) from mountain forests are highly relevant for human societies. ES with a direct economic support function (e.g. timber production), regulatory services (e.g. protection from natural hazards) and cultural services (e.g. recreation) are likely to be affected strongly by a rapidly changing climate. To evaluate whether adverse climate change effects on ES can be counteracted by adapting management, dynamic models and indicatorbased assessments are needed. 2. We applied a forest dynamic model in case study areas of four European mountain regions and evaluated the future supply of four EStimber production, carbon sequestration, biodiversity and protection against natural hazardsusing state-of-the-art ES indicators. Forest dynamics were simulated under three management scenarios (no management, business-as-usual and alternative management) and five climate change projections for selected representative stand types in each region. We analysed potential trade-offs and synergies between ES and evaluated future changes among regions, forest stands, climate and management scenarios. 3. Impacts of climate change on the provision of multiple ES were found to be highly heterogeneous and to depend on the region, site and future climate. In the absence of large-scale natural disturbance (not considered), protection services, carbon stock and deadwood abundance (proxy for biodiversity) benefitted from no management in all regions. Negative impacts of climate change were evident for the provision of multiple ES but limited to the most severe climate scenarios and low-elevation stands. Synergies and trade-offs between the majority of ES were found to be sensitive to the choice of management strategy andin some regionsto climate change. 4. Synthesis and applications. Management regimes in European mountain forests should be regionally adapted to stand and site conditions. Although in some cases alternative management regimes may be more suitable than current management for supporting multiple ecosystem services, adaptation options should be evaluated carefully at the local scale due to the highly different magnitude of the impacts of climate change in different regions and along elevation gradients.

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Future provisioning of ecosystem services (ES) from mountain forests is uncertain due to potential impacts of climate change. For a case study catchment in the Eastern Alps in Austria we analysed how management and climate change may affect the provisioning of four ES (timber production, carbon sequestration, biodiversity and bird habitat quality, and protection against gravitational hazards). We used the PICUS forest ecosystem model to project seven management alternatives that differed with regard to cutting pattern size (SLIT, PATCH, STRIP) and two harvesting intensity levels (in terms of return interval) under historic climate and five transient climate change scenarios over 100 years. In addition no management and sanitary management were simulated. In total twelve indicators were linked to model output to quantify ES provisioning. Results under historic climate showed increased volume and carbon stocks in low-intensity management, while high-intensity management decreased stocks. Bird habitat quality was maintained only by lowintensity management using SLIT and PATCH cuts. In particular rockfall protection decreased strongly under the STRIP cut scenario. Improved tree growth in warming scenarios was counterbalanced by increasing damage from bark beetle disturbances. Canopy openings and increased deadwood supply from disturbances partly fostered bird habitat quality in no-management alternatives. Overall none of the management alternatives performed best for all ES. PATCH and SLIT regimes at (currently practiced) low intensity appeared as compromise to achieve multifunctionality at small scale. As involved trade-offs among ES can be substantial, partial segregation with priority on specific services in designated zones is recommended.

In Central Europe, management of forests for multiple ecosystem services (ES) has a long tradition and is currently drawing much attention due to increasing interest in non-timber services. In face of a changing climate and diverse ES portfolios, a key issue for forest managers is to assess vulnerability of ES provisioning. In a case study catchment of 250 ha in the Eastern Alps, the currently practiced uneven-aged management regime (BAU; business as usual) which is based on irregularly shaped patch cuts along skyline corridors was analysed under historic climate (represented by the period 1961-1990) and five transient climate change scenarios (period 2010-2110) and compared to an unmanaged scenario (NOM). The study addressed (1) the future provisioning of timber, carbon sequestration, protection against gravitational hazards, and nature conservation values under BAU management, (2) the effect of spatial scale (1, 5, 10 ha grain size) in mapping ES indicators and (3) how the spatial scale of ES assessment affects the simultaneous provision of several ES (i.e. multifunctionality). The analysis employed the PICUS forest simulation model in combination with novel landscape assessment tools. In BAU management, timber harvests were smaller than periodic increments. The resulting increase in standing stock benefitted carbon sequestration. In four out of five climate change scenarios, volume increment was increasing. With the exception of the mildest climate change scenario (?2.6°C, no change in precipitation), all other analysed climate change scenarios reduced standing tree volume, carbon pools and number of large old trees, and increased standing deadwood volume due to an intensifying bark beetle disturbance regime. However, increases in deadwood and patchy canopy openings benefitted bird habitat quality. Under historic climate, the NOM regime showed better performance in all non-timber ES. Under climate change conditions, the damages from bark beetle disturbances increased more in NOM compared with BAU. Despite favourable temperature conditions in climate change scenarios, the share of admixed broadleaved species was not increasing in BAU management, mainly due to the heavy browsing pressure by ungulates. In NOM, it even decreased and mean tree age increased. Thus, in the long run NOM may enter a phase of lower resilience compared with BAU. Most ES indicators were fairly insensitive to the spatial scale of indicator mapping. ES indicators that were based on sparse tree and stand attributes such as rare admixed tree species, large snags and live trees achieved better results when mapped at larger scales. The share of landscape area with simultaneous provisioning of ES at reasonable performance levels (i.e. multifunctionality) decreased with increasing number of considered ES, while it increased with increasing spatial scale of the assessment. In the case study, landscape between 53 and 100 % was classified as multifunctional, depending on number and combinations of ES.

Forests provide countless ecological, societal, and climatological benefits. With changing climate, maintaining certain services may lead to a decrease in the quantity or quality of other services available from that source. Accordingly, our research objective is to analyze the effects of the provision of a certain ecosystem service on the economically optimized harvest schedules and how harvest schedules will be influenced by climate change. Based on financial portfolio theory, we determined, for two case study regions in Austria and Slovakia, treatment schedules based on nonlinear programming, which integrates climate-sensitive biophysical risks and risk-averting behavior of the management. In both cases, results recommend reducing the overaged stocking volume within several decades to establish new ingrowth, leading to an overall reduction of age and related risk, as well as an increase in growth. Under climate change conditions, the admixing of hardwoods towards spruce–fir–beech (Austria) or spruce–pine–beech (Slovakia) stands should be emphasized to account for the changing risk and growth conditions. Moreover, climate change scenarios either increased (Austria) or decreased (Slovakia) the economic return slightly. In both cases, the costs for providing the ecosystem service “rock fall protection” increases under climate change. Although in the Austrian case there is no clear tendency between the management options, in the Slovakian case, a close-to-nature management option is preferred under climate change conditions. Increasing tree species richness, increasing structural diversity, replacing high-risk stands, and reducing average growing stocks are important preconditions for a successful sustainable management of European mountain forests in the long term.