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Understanding the processes that shape forest functioning, structure, and diversity remains challenging, although data on forest systems are being collected at a rapid pace and across scales. Forest models have a long history in bridging data with ecological knowledge and can simulate forest dynamics over spatio‐temporal scales unreachable by most empirical investigations.We describe the development that different forest modelling communities have followed to underpin the leverage that simulation models offer for advancing our understanding of forest ecosystems.Using three widely applied but contrasting approaches – species distribution models, individual‐based forest models, and dynamic global vegetation models – as examples, we show how scientific and technical advances have led models to transgress their initial objectives and limitations. We provide an overview of recent model applications on current important ecological topics and pinpoint ten key questions that could, and should, be tackled with forest models in the next decade.Synthesis. This overview shows that forest models, due to their complementarity and mutual enrichment, represent an invaluable toolkit to address a wide range of fundamental and applied ecological questions, hence fostering a deeper understanding of forest dynamics in the context of global change., Forest models can help understanding the processes that shape forest functioning, structure and diversity, since they can can simulate forest dynamics over spatio‐temporal scales unreachable by most empirical investigations. Here we describe the development of three widely applied but contrasting forest mo−delling approaches — species distribution models, individual‐based models and dynamic global vegetation models. We provide an overview of recent model applications and pinpoint ten key questions that could, and should, be tackled with forest models in the next decade.

Boreal forests produce multiple ecosystem services for the society. Their trade-offs determine whether they should be produced simultaneously or whether it is preferable to assign separate areas to different ecosystem services. We use simulation and optimization to analyse the correlations, trade-offs and production levels of several ecosystem services in single- and multi-objective forestry over 100 years in a boreal forest landscape. The case study area covers 3600 ha of boreal forest, consisting of 3365 stands. The ecosystem services and their indicators (in parentheses) considered are carbon sequestration (forestry carbon balance), biodiversity (amount of deadwood and broadleaf volume), economic profitability of forestry (net present value of timber production) and timber supply to forest industry (volume of harvested timber). The treatment alternatives simulated for each of the stands include both even-aged rotation forestry (thinning from above with clear cut) and continuous cover forestry regimes (thinning from above with no clear cut). First, we develop 200 Pareto optimal plans by maximizing multi-attribute utility functions using random weights for the ecosystem service indicators. Second, we compare the average level of ecosystem services in single- and multi-objective forestry. Based on our findings, forestry carbon balance and the amount of deadwood correlate positively with each other, and both of them correlate negatively with harvested timber volume and economic profitability of forestry. Despite this, the simultaneous maximization of multiple objectives increased the overall production levels of several ecosystem services, which suggests that the management of boreal forests should be multi-objective to sustain the simultaneous provision of timber and other ecosystem services.

Vast areas of Zagros Forests in Iran are mainly stocked by old oak trees have been subject to traditional land use practices which resulted in failure of oak regeneration to pass the browsing horiz...

Since 2000, adaptation has been the focus of the response to climate change in many least developed countries. However, there are recognized overlaps and tensions between mitigation, adaptation and...

Forest ecosystem models, being widespread science tools and used for forest management decision support are usually evaluated individually against field data sets, while model intercomparison and joint evaluation studies are rare. We tested five forest models according to a harmonized protocol against data from nine forest compartments in the Snĕžnik region, in Slovenia. The suite of models included stand- and landscape-scale, empirical- and process-based models used across Europe. The test dataset originated from inventory data covering 50 years (tree measurements 1963, 1983 and 2013) and included annual harvesting records at tree level. Uncertainties in data and forest conditions were considered by defining 12 scenarios varying initial regeneration, browsing pressure and harvest modalities. We evaluated the models` ability to initialize forest conditions accurately, whether management interventions could be implemented based on harvest records, and how well basal area and diameter structure could be predicted. Simulation results for basal area development showed good to satisfactory performance for all models, at which SAMSARA2, SIBYLA and PICUS showed the best agreement. Comparison of simulated and observed diameter distributions showed good performance of ForClim, PICUS, SAMSARA2 and SIBYLA. Model output variability was between 6% and 24%, indicating the relevance to consider uncertainties that can be attributed to specific sources. There was no clear hierarchy between more empirical or more process-based models regarding accuracy of stand development projections. The cohort-based landscape model LandClim showed the lowest stand-level accuracy and scenario sensitivity, but results nevertheless qualified it for complementary application at landscape scale. Within individual-based models, spatially explicit models seemed to be more suitable for heterogeneous mixed mountain forests. The findings demonstrated the usefulness of inventory datasets for model testing and intercomparison., Ecological Modelling, 445, ISSN:0304-3800, ISSN:1872-7026, ISSN:0167-8892

On the selected sites in the investigated Oriental beech ( Fagus orientalis L.) dominated forests in Iran with an extensive individual tree selection system, tree microhabitats (MH) are more influenced by tree level factors such as tree species and DBH than by plot level factors such as plot basal area or size and species diversity. Despite the ecological importance of tree microhabitats for biodiversity, there is a lack of information about the occurrence of microhabitat features in Hyrcanian forests in Northern Iran. The aims of this study were to assess selected MH types on living trees in forests managed with an individual tree selection system and forests unmanaged since at least 30 years and to study the effect of tree and plot level factors on their occurrence. A total of 120 circular sample plots were used to collect tree level microhabitat information at six different sites in Oriental beech forests in Iran. Pairs of managed and recently unmanaged forests were located at six sites. Generalized linear mixed models were employed to analyze (i) the effect of management on microhabitat occurrence, and (ii) to explain the occurrence of microhabitats at tree level. There was no significant difference in total number of assessed microhabitats per ha in forests managed with a low-intensity management regime with individual tree selection versus recently unmanaged forests (no management intervention for at least 30 years). Stem cavity with decay was by far the most frequent microhabitat type in managed (16.5 per ha) as well as in recently unmanaged forests (14.2 per ha). Hornbeam and oak trees have a higher probability to host microhabitats (bark loss, woodpecker cavity, and stem cavities) than the dominant oriental beech. Suppressed trees indicated by basal area of larger trees have a lower probability to show bark loss and conks of fungi. Models of microhabitat occurrence on trees have potential to support the development of management guidelines to foster biodiversity.

The main ecosystem services (ES) central European mountain forests provide are: protection against gravitational hazards, timber production, recreation, biodiversity conservation and carbon storage, which are all in high demand. These demands make managing mountain forests a challenging task, involving manifold synergies and conflicts between the different ES. There is therefore an urgent need for appropriate concepts and tools for support decisions in forest management and planning (FMP) to take into consideration all ES and to manage the wide variety of information types, parameters and uncertainties involved in assessing the sustainability of ES. Multi-criteria decision analysis (MCDA) provides a suitable set of methods for sustainability evaluations. In this study sustainability means the persistent fulfilment of the required ES. To address all the phases of the FMP process, MCDA and forest models should be applied together, with indicators providing the main interfaces to combine them. This paper aims to: i) review assessment approaches in order to select appropriate and widely accepted indicators for measuring and assessing the effects of different silvicultural management alternatives on forest ES, and ii) present additional standardisation approaches (value functions) for each indicator. Standardisations are necessary to make the different ES comparable and to study synergies and trade-offs between different management objectives in MCDA. The main ES in central European mountain regions are considered, with a clear focus on those indicators that are directly derivable from forest model outputs and that can refer to sustainable forest management practices. The scales considered are that of the single forest stand and of the larger forest management unit. A holistic indicator-based analysis framework for FMP in mountain forests can be built using the indicators and value functions described. The influence of different management alternatives on ES can then be evaluated, taking into consideration the instruments and information on forest management (forest models, inventory) available. All indicators are selected according to existing and approved approaches that only require data that is normally available in operational forest management. The framework can thus be an important element in developing a decision support system for FMP in mountain forests.

Forest disturbances are sensitive to climate. However, our understanding of disturbance dynamics in response to climatic changes remains incomplete, particularly regarding large-scale patterns, interaction effects and dampening feedbacks. Here we provide a global synthesis of climate change effects on important abiotic (fire, drought, wind, snow and ice) and biotic (insects and pathogens) disturbance agents. Warmer and drier conditions particularly facilitate fire, drought and insect disturbances, while warmer and wetter conditions increase disturbances from wind and pathogens. Widespread interactions between agents are likely to amplify disturbances, while indirect climate effects such as vegetation changes can dampen long-term disturbance sensitivities to climate. Future changes in disturbance are likely to be most pronounced in coniferous forests and the boreal biome. We conclude that both ecosystems and society should be prepared for an increasingly disturbed future of forests. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.

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 low-intensity 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.

The transformation towards a low-carbon bioeconomy until 2050 is one of the main strategic long-term targets of the European Union. This work presents transformation scenarios for the case of Austria with GHG reduction to about 20% of Kyoto baseline. The scenarios are developed with an optimization model integrating the energy sector, land use and biomass flows. Focus is on investigating possible developments in domestic biomass supply and use. Biomass is crucial for (largely) decarbonising the energy system and replacing fossil-based and energyintensive materials. Domestic biomass use (dry mass) increases by 32% in an 'intensive' and 11% in an 'alternative' transformation scenario, while total energy consumption decreases by 40%. Transformation to a low-carbon bioeconomy could be accomplished without additional biomass imports. Keywords: Low-carbon economy, Bioeconomy, Scenario, Decarbonisation, Biomass

Recommendations on suitable seed sources for reforestation are usually model based and include uncertainties arising from model assumptions, parameter estimation, and future climate scenarios. Due to the long-lived nature of forests, such uncertainties need to be considered when developing guidance for managers and policy makers. We evaluate the uncertainties and apply our recently developed genetically based models, Universal Response Functions (URFs) in Austria and Germany. The URFs predict growth performance (dominant height and basal area at age 24) of Douglas-fir (Pseudotsuga menziesii [Mirbel] Franco) populations, as a function of both environmental and genetic factors. We evaluated the URFs by comparing the predicted height growth performances with observations from independent provenance trial data across Europe. Also, the sensitivity of the URF variables and the overall model uncertainty were estimated and compared to the uncertainty due to climate change projections. Model evaluation suggests that the URFs perform better in Central and Southeastern Europe compared to maritime Western Europe. Summer drought and mean annual temperature of planting sites were the most sensitive variables of the models, whereas the mean annual temperature of seed origin was the least sensitive. Model uncertainty increased with mean annual temperature of the planting site. Uncertainty due to projected future climate was found to be higher than the model uncertainty. The URFs predicted that provenance regions of southwest Germany and southeast Austria below 1500 m altitude will be suitable, whereas Pannonian east of Austria will become less suitable for growing Douglas-fir in future. Current seed stands in North America providing planting materials for Europe under the legal framework of the Organization for Economic Cooperation and Development shall continue to provide the most suitable seed material also in the future.

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.

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.

Climate change is set to increase landslide frequency around the globe, thus increasing the potential exposure of people and material assets to these disturbances. Landslide hazard is commonly modelled from terrain and precipitation parameters, assuming that shorter, more intense rain events require less precipitation volume to trigger a slide. Given the extent of non-catastrophic slides, an operable vulnerability mapping requires high spatial resolution. We combined heterogeneous regional slide inventories with long-term meteorological records and small-scale spatial information for hazard modelling. Slope, its (protective) interaction with forest cover, and altitude were the most influential terrain parameters. A widely used exponential threshold to estimate critical precipitation was found to incorrectly predict meteorological hazard to a substantial degree and, qualitatively, delineate the upper boundary of natural conditions rather than a critical threshold. Scaling rainfall parameters from absolute values into local probabilities (per km&sup2, ) however revealed a consistent pattern across datasets, with the transition from normal to critical rain volumes and durations being gradual rather than abrupt thresholds. Scaled values could be reverted into site-specific nomograms for easy appraisal of critical rain conditions by local stakeholders. An overlay of terrain-related hazard with infrastructure yielded local vulnerability maps, which were verified with actual slide occurrence. Multiple potential for observation bias in ground-based slide reporting underlined the value of complementary earth observation data for slide mapping and early warning.

The vulnerability of forest ecosystem services to climate change is expected to depend on landscape characteristic and management history, but may also be influenced by the proximity to the southern range limit of constituent tree species. In the Western Rhodopes in South Bulgaria, Norway spruce is an important commercial species, but is approaching its current southern limit. Using climate sensitive forest models, we projected the impact of climate change on timber production, carbon storage, biodiversity and soil retention in two representative landscapes in the Western Rhodopes; a lower elevation landscape (1000–1450 m a.s.l) dominated by mixed species forests, and a higher elevation landscape (1550–2100 m a.s.l.) currently dominated by spruce. In both landscapes climate change is projected to induce a shift in forest composition, with drought-sensitive species, such as Norway spruce, being replaced by more drought-tolerant species such as Scots pine and black pine at lower elevations. In the higher elevation landscape a reduction in spruce growth is projected, particularly under the more severe climate change scenarios. Under most climate scenarios a reduction in growing stock is projected to occur, but under some scenarios a moderate increase in higher elevation stands (>1500 m a.s.l.) is expected. Climate change is projected to negatively influence carbon storage potential across landscapes with the magnitude depending on the severity of the climate change scenario. The impact of climate change on forest diversity and habitat availability is projected to differ considerably between the two landscapes, with diversity and habitat quality generally increasing at higher elevations, and being reduced at lower elevations. Our results suggest that if currently management practices are maintained the sensitivity of forests and forest ecosystem services in the Western Rhodopes to climate change will differ between low and higher elevation sites and will depend strongly on current forest composition.

We used the coupled forest and rockfall model PICUS Rock’n’Roll, linking a hybrid forest patch model and a 3D rockfall model, to assess the effects of four management scenarios (BAU: business as usual age class shelterwood approach; PFM1 and PFM2: rockfall protection management scenarios with slit-shaped gaps; NOM: no management scenario without any active silvicultural intervention) on rockfall protection and timber production on a 38 ha slope over 100 years. Compared to PFM1 and PFM2, we found slightly more harvested timber for the BAU scenario (BAU: 6.7 m³ha−1yr−1, PFM: 5.7–5.9 m³ha−1yr−1), but lower contribution margins (BAU: 55 €ha−1yr−1, PFM: 113–115 €ha−1yr−1). Overall, depending on rock size and forest state, 30–70% of the simulated rocks that would otherwise hit the road at the foot of the slope were stopped by the forest. While the PFM scenarios maintained a high rockfall protection level over 100 years (PE between 45–64%) the BAU showed periods of reduced protection (PE between 26–65%). The NOM...

In Central European mountain forests, timber production and the protection of infrastructure and settlements against gravitational natural hazards are key forest ecosystem services (ES). The quantitative assessment of mountain forest ES for management planning and decision support is a particular challenge, due to manifold involved spatial scales from tree to slope and landscape level. We present an assessment framework to analyze and communicate the effect of management and climate change on the provision of selected ES in mountain forests. Core element is the spatially explicit hybrid forest ecosystem model PICUS. Remote sensing data and inventories are combined to generate realistic fine-grained forest landscapes with single tree resolution as input to PICUS. Landscape-level planning of silvicultural prescriptions employs geographic information systems functionalities (locate skyline corridors and treatment areas, prescribe silvicultural operations based on tree-level attributes) and produces management maps, which are interpreted by PICUS and executed in course of simulation runs. Model output is imported into a spatially explicit landscape assessment tool to assess the protective effect of vegetation. In a 250 ha case study in the Eastern Alps in Austria, the assessment framework is demonstrated to evaluate effects of climate change and management on timber production and protection against landslides and snow avalanche release. Climate change had, depending on climate and management scenario both, positive and negative impacts on desired ES. Key factor for ES provisioning in the case study was the interaction of bark beetle disturbances, legacies of past land-use practices and forest management.

Mountain forests provide a diverse range of ecosystem services (ES). In case of conflicting ES, trade-offs must be considered in forest resource planning. In this study, simulation-based scenario analysis and multi-criteria decision analysis is used to analyse expected utilities and value-based trade-offs in multi-objective forest management related to four key ES (timber production, carbon storage, biodiversity conservation, protection against gravitational hazards) in three European mountain regions. In each case study area a set of management alternatives including no-management were simulated over 100 years and ES quantified using ES indicators. Multifunctional goal scenarios are employed to aggregate partial ES utilities, accumulated RMSE between ES are used to quantify trade-offs. In two analysed case study areas no-management generated highest ES utilities for biodiversity conservation, carbon storage and protection against gravitational hazards. Alternatives based on small-scale silviculture combined timber production and biodiversity conservation very well. In all case study areas increasing goal preferences for timber production or biodiversity and nature conservation result in increasing overall trade-offs with rather decreasing overall utilities. In all case study areas the analysed managements support multiple ES and can thus be considered as multifunctional. Based on the presented analysis management alternatives could be further improved.

International audience; Mountain forests provide a multitude of services beyond timber production. In a large European project (ARANGE—Advanced multifunctional forest management in European mountain RANGEs), the impacts of climate change and forest management on ecosystem services (ES) were assessed. Here, we provide background information about the concept that was underlying the ARANGE project, and its main objectives, research questions, and methodological approaches are presented. The project focused on synergies and trade-offs among four key ES that are relevant in European mountain ranges: timber production, carbon storage, biodiversity conservation, and protection from gravitational natural hazards. We introduce the concept and selection of case study areas (CSAs) that were used in the project; we describe the concept of representative stand types thatwere developed to provide a harmonized representation of forest stands and forest management in the CSAs; we explain and discuss the climate data and climate change scenarios that were applied across the seven CSAs; and we introduce the linker functions that were developed to relate stand- and landscape-scale forest features from model simulations to ES provisioning in mountain forests. Finally, we provide a brief overview of the Special Feature, with an attempt to synthesize emerging response patterns across the CSAs.

Recent studies projecting future climate change impacts on forests mainly consider either the effects of climate change on productivity or on disturbances. However, productivity and disturbances are intrinsically linked because 1) disturbances directly affect forest productivity (e.g. via a reduction in leaf area, growing stock or resource-use efficiency), and 2) disturbance susceptibility is often coupled to a certain development phase of the forest with productivity determining the time a forest is in this specific phase of susceptibility. The objective of this paper is to provide an overview of forest productivity changes in different forest regions in Europe under climate change, and partition these changes into effects induced by climate change alone and by climate change and disturbances. We present projections of climate change impacts on forest productivity from state-of-the-art forest models that dynamically simulate forest productivity and the effects of the main European disturbance agents (fire, storm, insects), driven by the same climate scenario in seven forest case studies along a large climatic gradient throughout Europe. Our study shows that, in most cases, including disturbances in the simulations exaggerate ongoing productivity declines or cancel out productivity gains in response to climate change. In fewer cases, disturbances also increase productivity or buffer climate-change induced productivity losses, e.g. because low severity fires can alleviate resource competition and increase fertilization. Even though our results cannot simply be extrapolated to other types of forests and disturbances, we argue that it is necessary to interpret climate change-induced productivity and disturbance changes jointly to capture the full range of climate change impacts on forests and to plan adaptation measures., published version, peerReviewed

This study addresses the impact of climate change and management approach on the provision of four ecosystem services (ES) (timber production, protection against gravitational hazards, carbon sequestration and biodiversity) in Valsaín forest in central Spain. The hybrid forest patch model PICUS v1.6 was used to simulate the development of 24 representative stand types over 100 years (2010–2110) in a full factorial simulation experiment combining three management regimes [“business as usual” management (BAU) and two alternatives to BAU (AM1 and AM2)], a no-management scenario (NOM) and six climate scenarios (historic climate represented by the period 1961–1990 and five transient climate change scenarios). Simulations indicated relatively small differences as regards the impact of the different management alternatives (BAU, AM1 and AM2) on the provision of ES as well as a clear improvement in biodiversity, protection and carbon storage under the no-management regime (NOM). Although timber production indicators were the most sensitive to climate change scenarios, biodiversity-related indicators responded fastest to the management regimes applied. Indicators of protection against rockfall and landslides were affected by both management and climate change. The results indicate substantial vulnerability of ES provisioning under the more extreme climate change scenarios at low elevations (1250 m). At higher elevations, the productivity of Scots pine stands may show a moderate decrease or increase, depending on the climate change scenario. © 2016, Springer-Verlag Berlin Heidelberg.

Oak forests of Iran are managed for soil conservation, water quality and other non-market ecosystem services. Nationalization policies in 1963 implied shifts from private ownership and informal traditional management to public ownership and state forest management. In spite of the nationalization, informal practices and conventional ownership have been continued which has caused considerable conflicts between local people and the state forest administration. The aim of the study was to systematically gather the components of traditional silvopastoral management in these oak forests and to investigate the effects of these practices on forest stand structure. To understand how the traditional forest management system works, empirical survey methods, in particular face to face interviews and participation in traditional practices have been employed. In general, local livelihoods depend on three main components: animal husbandry, farming and forestry, which are all spatially interrelated in the territories of individual families. Silvopastoral management is based on a well-developed foundation of traditional ecological knowledge (TEK) which has been shaped over time and conducted for sustainable utilization of oak forests in northern Zagros. Forest regulation and tree characteristics were developed under traditional rules to provide fodder using a set of practices, including pollarding of oak trees as an essential feature of traditional land use in northern Zagros. The impacts of traditional forest management on forest structure, regeneration and composition were investigated by comparing pollarded stands with adjacent undisturbed reference sites. Our analyses show lower woody species richness in managed stands than at reference sites. Stand structure is affected by traditional practices in regard to stand density, stocking, crown cover percentage, diameter distribution type and spacing. Regeneration failure due to heavy livestock browsing is considered the main weakness of the system. We conclude that respectful conventional regulations and customs can provide bedrock to conservation of the forest area. In this regard the role of traditional forest management and community-based approaches should be acknowledged to encourage public participation for sustainable forest management.

Bark beetles are the major biotic disturbance factor threatening Norway spruce (Picea abies [L.] karst.) forests in Austria. The increase of bark beetle salvage after large storm damages is well known. However, over the recent two decades salvage from bark beetle damages in Austria has increased and varied between 0.6 and 3.0 million m3, where at regional scale a complex interplay of initial beetle population density, forest conditions, weather phenomena such as drought periods, various other disturbance agents such as snow and storm and forest management have been hypothesized as major determinants. This points at the need to develop tools to assess the risks of damage from bark beetle disturbances at the operational scale of forest stands, so that adaptation measures can be developed and implemented in a targeted approach. In the current analysis, binomial generalized linear mixed models (GLMMs) were used to assess the effects of site, stand and climate conditions on the probability, and linear mixed models (LMMs) for the intensity of bark beetle disturbance events at forest stand level. The database used for model development combined 10-year forest management plans and related harvest records of four management units of the Austrian Federal Forests covering in total more than 40,000 ha of forest, and a gridded climate data set provided by the Austrian Central Institution for Meteorology and Geodynamics. In the models, timber stock volume and previous disturbances had the largest impacts on bark beetle damage. Potential bark beetle generations estimated from a beetle phenology model were also a useful predictor. While the model of disturbance probability correctly classified 90% of all cases in the data set (specificity 95%, sensitivity 29%), the model for damage intensity explained only low shares of the variation in the recorded damage data (full model R2 = 0.45, fixed-effects-only model R2 = 0.13; cross validation in the four forest management units yielded similar R2 values). Benefits and limitations of the data set are critically discussed and conclusions for operational forest management are drawn.

International audience; In many parts of Europe, close-to-nature silviculture (CNS) has been widely advocated as being the best approach for managing forests to cope with future climate change. In this review, we identify and evaluate six principles for enhancing the adaptive capacity of European temperate forests in a changing climate: (1) increase tree species richness, (2) increase structural diversity, (3) maintain and increase genetic variation within tree species, (4) increase resistance of individual trees to biotic and abiotic stress, (5) replace high-risk stands and (6) keep average growing stocks low. We use these principles to examine how three CNS systems (single-tree selection, group selection and shelterwood) serve adaptation strategies. Many attributes of CNS can increase the adaptive capacity of European temperate forests to a changing climate. CNS promotes structural diversity and tree resistance to stressors, and growing stocks can be kept at low levels. However, some deficiencies exist in relation to the adaptation principles of increasing tree species richness, maintaining and increasing genetic variation, and replacing high-risk stands. To address these shortcomings, CNS should make increased use of a range of regeneration methods, in order to promote light-demanding tree species, non-native species and non-local provenances.

The design and implementation of the adaptive forest management (AFM) ToolBox is presented. Design principles derived from previous experiences in decision support system (DSS) development include support for (1) modularity, (2) accessibility via the Internet, (3) inclusion of different types of knowledge and information, (4) the use of different data sources, and (5) specific problem types. As major components of the AFM ToolBox DataBase, Vulnerability Assessment Tools (single user version, group mode) and an optimization tool to generate optimized management plans at the level of management units or landscapes are highlighted. A key feature is the distinction of two archetypical user profiles (manager, analyst). The AFM ToolBox is evaluated against eight criteria for the assessment of DSS. It is concluded that the ToolBox approach setting focus on modularity while avoiding to over-emphasis technical integration provides the right frame to secure the flexibility regarding tools and decision-making proces...

The potential for development in decision support for forest management is set by decision theory, available technology and methods. Demands for decision support are emerging from contemporary challenges and problems of forest management which act as stimuli for the science community. Objectives and approaches in forest management as well as technologies have been changing throughout history. Accordingly, the demand for tools to support planning and decision-making has evolved. In this contribution, the authors review the historic development of decision support systems (DSS) for forest management and discuss past, current and future drivers. Based on evidence from scientific literature, case studies in the frame of the Forest Management Decision Support Systems (FORSYS) action, as well as experiences of the authors some hypotheses about the future of DSS are drawn. It is shown that in the past, the drivers evolving from forest management as well as decision support technologies have influenced the way of...

Small-diameter hardwood (SDH) in Austria is currently a mass input for energetic use (fuel wood, heat plants) and pulp production. Its use is non-selective and non-distinctive with regard to wood quality and potential for value generation. Sustainability impact assessment methodology is applied for the stages of forest management, harvest & transport and wood processing & industries to test alternative ways of SDH use with a higher share of material use. A higher amount of material use of SDH due to improved forest management, sorting, logistics and sawing techniques may lead to overall more sustainable wood-based value chains, including a more balanced benefit sharing and value creation within regions and rural areas, along sub-sectors as well as across sustainability dimensions, and to higher efficiency of wood consumption in terms of cascade use and carbon storage. Enhanced cooperatives in the forest-based sector and active support by coherent regional policies on the use of natural resources ...

Although they were originally introduced for different purposes, forest models are often used today for scenario development, which includes forest production as one aspect of forest development. However, studies using an independent data set to compare different simulators are rarely found. In this study a subset of National Forest Inventory data for the whole of Austria was compared to simulations of the biogeochemistry model Biome-BGC, the hybrid gap model PICUS and a climate sensitive version of the growth and yield model PrognAus. The models were used to simulate the development of approximately 700 forest inventory sample plots over a period of 15?years. The study focussed on the models' sensitivity to varying environmental conditions; thus, the comparison was based on the mean current annual volume increment per hectare. All models showed a significant average deviation from the inventory (over- or under-estimation). The estimated year-to-year variation was best reproduced by PICUS. However, the 15?year growth trend was also shown by Biome-BGC and PrognAus. Potential model users interested in relating mean current annual volume increment to climate data will need to weigh accuracy against applicability when choosing among these models. Highlights? We compare simulations by a BGC model, a gap model and an empirical growth model. ? The comparison is based on the current annual volume increment for 1987-2001. ? All models show a significant average deviation from inventory. ? The year-to-year increment variation was best reproduced by the gap model. ? Complex models lose applicability due to extended input data needs.

The unabated continuation of anthropogenic greenhouse gas emissions and the lack of an international consensus on a stringent climate change mitigation policy underscore the importance of adaptation for coping with the all but inevitable changes in the climate system. Adaptation measures in forestry have particularly long lead times. A timely implementation is thus crucial for reducing the considerable climate vulnerability of forest ecosystems. However, since future environmental conditions as well as future societal demands on forests are inherently uncertain, a core requirement for adaptation is robustness to a wide variety of possible futures. Here we explicitly address the roles of climatic and social uncertainty in forest management, and tackle the question of robustness of adaptation measures in the context of multi-objective sustainable forest management (SFM). We used the Austrian Federal Forests (AFF) as a case study, and employed a comprehensive vulnerability assessment framework based on ecosystem modeling, multi-criteria decision analysis, and practitioner participation. We explicitly considered climate uncertainty by means of three climate change scenarios, and accounted for uncertainty in future social demands by means of three societal preference scenarios regarding SFM indicators. We found that the effects of climatic and social uncertainty on the projected performance of management were in the same order of magnitude, underlining the notion that climate change adaptation requires an integrated social-ecological perspective. Furthermore, our analysis of adaptation measures revealed considerable trade-offs between reducing adverse impacts of climate change and facilitating adaptive capacity. This finding implies that prioritization between these two general aims of adaptation is necessary in management planning, which we suggest can draw on uncertainty analysis: Where the variation induced by social-ecological uncertainty renders measures aiming to reduce climate change impacts statistically insignificant (i.e., for approximately one third of the investigated management units of the AFF case study), fostering adaptive capacity is suggested as the preferred pathway for adaptation. We conclude that climate change adaptation needs to balance between anticipating expected future conditions and building the capacity to address unknowns and surprises.

Climate change may strongly impact on forests and affect the provisioning of forest ecosystem services. The identification, design, selection and implementation of adaptive measures in forest management requires a sound knowledge base as well as tools to support the forest manager in decision making. Decision support systems (DSS) are considered as particularly useful to assist in dealing with ill structured decision making problems. Forest management planning and decision making deals with highly complex socio-ecological systems with multiple interacting spatial and temporal dimensions. Finding ways and means to communicate findings about such complex relationships in forest ecosystems and their management via information technology is a challenge in itself. This is amplified if decision problems include land use change and climate change issues as uncertainty in planning outcomes increases. The literature reports numerous attempts to develop DSS for forest management. However, recently several review papers conclude that there has been only limited uptake of DSS into practice because frequently user demands and the characteristics of decision problems are not considered properly. In this contribution we propose five design principles for forest management DSS: (1) modularity, (2) accessibility via the internet, (3) inclusion of different types of knowledge and information, (4) possibility to use different data sources, and (5) support of specific problem types. Based on these principles we promote a ToolBox approach attempting to meet context specificity as well as flexibility addressing different user and problem types simultaneously. The AFM (Adaptive Forest Management) ToolBox is introduced and the conceptual design and technical implementation of the ToolBox is presented. The combination of different decision support techniques (e.g. vulnerability assessment, multi-criteria analysis, optimization) allows to support all phases of the decision making process and provides the user with the flexibility to interpret the information in various forms. The results of a self-assessment of the ToolBox against eight evaluation criteria for DSS are combined with a feedback from a panel of expert users who had tested the usability and had evaluated the conceptual approach of the ToolBox. The feedback stimulates the further development and ultimately will increase the level of acceptance by potential users. It is concluded, that the ToolBox approach focusing on modularity while avoiding over-emphasis of technical integration provides the right frame to secure the flexibility to add new tools and improve the support of decision making processes which is mandatory if a DSS should be taken up by practice.

Natural disturbances like wildfire, windthrow and insect outbreaks are critical drivers of composition, structure and functioning of forest ecosystems. They are strongly climate-sensitive, and are thus likely to be distinctly affected by climatic changes. Observations across Europe show that in recent decades, forest disturbance regimes have intensified markedly, resulting in a strong increase in damage from wind, bark beetles and wildfires. Climate change is frequently hypothesized as the main driving force behind this intensification, but changes in forest structure and composition associated with management activities such as promoting conifers and increasing standing timber volume (i.e. ‘forest change’) also strongly influence susceptibility to disturbances. Here, we show that from 1958 to 2001, forest change contributed in the same order of magnitude as climate change to the increase in disturbance damage in Europe's forests. Climate change was the main driver of the increase in area burnt, while changes in forest extent, structure and composition particularly affected the variation in wind and bark beetle damage. For all three disturbance agents, damage was most severe when conducive weather conditions and increased forest susceptibility coincided. We conclude that a continuing trend towards more disturbance-prone conditions is likely for large parts of Europe's forests, and can have strong detrimental effects on forest carbon storage and other ecosystem services. Understanding the interacting drivers of natural disturbance regimes is thus a prerequisite for climate change mitigation and adaptation in forest ecosystem management.

Sustaining forest ecosystem functions and services under climate change is a major challenge for forest manage- ment. While conceptual advances of adapting coupled social-ecological systems to environmental changes have been made recently, good practice examples at the operational level still remain rare. The current study presents the development of adaptation options for 164 550 ha of commercial forests under the stewardship of the Austrian Federal Forests (AFF). We used a comprehensive vulnerability assessment as analysis framework, employing ecosystem modeling and multicriteria de- cision analysis in a participatory approach with forest planers of the AFF. An assessment of the vulnerability of multiple ecosystem goods and services under current management served as the starting point for the development of adaptation op- tions. Measures found to successfully reduce vulnerability include the promotion of mixed stands of species well adapted to emerging environmental conditions, silvicultural techniques fostering complexity, and increased management intensity. As- sessment results for a wide range of site and stand conditions, stand treatment programs, and future climate scenarios were used to condense robust recommendations for adapting the management guidelines currently used by AFF practitioners. Overall, our results highlight the importance of timely adaptation to sustain forest goods and services and document the re- spective potential of silvicultural measures. Resume : Le maintien des fonctions et services de l'ecosysteme forestier malgre le changement climatique represente un defi majeur pour l'amenagement forestier. Bien que des progres conceptuels pour adapter les systemes socio-ecologiques combines aux changements environnementaux aient ete accomplis recemment, les exemples de bonnes pratiques a l'echelle operationnelle sont encore rares. Cette etude presente le developpement d'options d'adaptation pour 164 550 ha de forets commerciales gerees par l'entreprise « Austrian Federal Forests » (AFF). Nous avons utilise une evaluation poussee de vul- nerabilite comme cadre d'analyse en ayant recours a la modelisation ecosystemique et a l'analyse de decision multicritere dans une approche participative avec les gestionnaires forestiers de l'AFF. Une evaluation de la vulnerabilite des multiples biens et services de l'ecosysteme dans le cadre de l'amenagement actuel a servi de point de depart pour le developpement d'options d'adaptation. Les mesures capables de reduire la vulnerabilite incluent la promotion des peuplements melanges avec des essences bien adaptees aux conditions environnementales emergentes, les techniques sylvicoles qui favorisent la complexite et un amenagement plus intensif. Les resultats de l'evaluation pour une large gamme de stations et de conditions de peuplement, de programmes de traitement des peuplements et de scenarios climatiques futurs ont servi a formuler des re- commandations robustes pour adapter les lignes directrices d'amenagement actuellement utilisees par les praticiens de l'AFF. Dans l'ensemble, nos resultats font ressortir l'importance d'une adaptation opportune pour maintenir les biens et ser- vices de la foret et documenter le potentiel des differentes interventions sylvicoles. (Traduit par la Redaction)

Sustainability impact assessment (SIA) is a prospective, integrated assessment approach for potential impacts of policy actions. Multi-criteria analysis (MCA) can be used to facilitate a multi-indicator evaluation in this framework in order to foster rational and transparent decision-making processes for SIA. Based on the outputs of the EFORWOOD project, this paper presents an exploratory MCA to a regional forest-wood chain (FWC) in Baden–Wurttemberg. This assessment is based on a set of sustainability indicators at process level for a baseline year 2005, reference futures ‘A1’ and ‘B2’ following the definition of the IPCC and a bio-energy scenario implanted into the reference future ‘A1’. The indicator values were calculated by the process tool ToSIA. It is demonstrated how time steps for parts of the regional FWC (forest management, harvest and transport to the mill gate) can be evaluated, as well as the outcomes of different scenarios for a time period. For this purpose, a novel software tool, ToSIA-MCA, is used to calculate relative sustainability impact rating (SIR) based on a PROMETHEE II algorithm. Further, we performed uncertainty analysis to test the stability of ranking results in the absence of real preference information with regard to uncertainty in indicator data. By comparing different indicator weighting patterns, the sensitivity of SIR calculation was further tested. The exploratory MCA outcomes are critically evaluated against the background of assumptions, and data used in the regional case, and an outlook is given on the importance to gain stronger stakeholder involvement in real-life applications.

Due to the emerging importance of sustainable use of natural resources, and policies requiring actions towards sustainable development, there is a demand for methodologies and tools that are able to address these new challenges. In this paper, an approach to assess sustainability impacts of alternative production chains of the forest sector is presented. The approach, which is designed for both public and private decision-makers, describes the forest sector as a set of processes by which forest resources are used to (1) produce biomass which is routed through different value-adding production chains and converted to products and (2) provide other ecosystem services. It is suggested that each production process included in a production chain will be characterised by a set of indicators covering environmental, economic and social aspects of sustainable development. The approach is demonstrated by a numerical example, in which the indicator values are determined based on the volume of wood material flowing through the processes. Sustainability impacts of policy scenarios or technological changes result from changing from one production chain to another; the impacts accumulate along the production chains. Combined cost–benefit and multi-criteria analyses are proposed to evaluate overall impacts and to compare alternative chains.

Considering climatic uncertainties in management planning is a prerequisite for sustainable forest management (SFM). The aim of the study was to evaluate climate change vulnerability of the current SFM strategy for commercial forests managed by the Austrian Federal Forests. To that end vulnerability indicators were defined in a stakeholder process (selected indicators were productivity, timber and carbon stocks, biodiversity, disturbances, a tree species’ position in fundamental niche space, silvicultural flexibility and cost intensity) and their performance under climate change scenarios assessed with an ecosystem model. Multi criteria analysis techniques were employed in a partial aggregation of indicators to locate forest stands on a vulnerability surface. Results revealed high vulnerability particularly in the second half of the twenty-first century, where 39.6% of the 164.550 ha study area were assessed highly vulnerable to climate change, indicating a strong decline in the functions and services represented by the indicator system. Water-limited sites on calcareous bedrock were most negatively affected whereas assessment units at higher altitudes responded predominately positive to climate warming. The presented approach, transparently integrating multiple management objectives and allowing a quantitative comparison of vulnerabilities between sites and management strategies, contributes to the development of operational and efficient climate change adaptation measures in forest management.

Mediterranean pines account for 14,000 ha in Tuscany alone, where they form large and homogeneous stands and represent an important resource for the forest economy. Among the harvesting systems applied to thinning operations, the most popular are whole-tree and cut-to-length harvestings. Both systems can be deployed with different levels of mechanization. The decision about which system might be the best option in a specific case possibly leads to conflicts due to different management goals, for instance when the shift from cut-to-length to whole-tree harvesting systems results in a decrease of costs and an increase of environmental burdens. Thus, an accurate determination of economic, environmental and social indicators is crucial to make balanced decisions. With that in mind, we carried out a sustainability impact assessment of typical forest-wood chain alternatives applied to young Mediterranean pine plantations and made a comparative evaluation by means of multi-criteria analyses. Trials were carried out in umbrella pine (Pinus pinea L.) plantations in Tuscany. The analyzed cases considered four thinning operations and included the processes of harvesting, extraction and chipping. In the analysis, 12 indicators were considered (e.g., global warming potential, fatal accidents). Results of the investigation allow quantifying possible sustainability impacts and, thus, supporting management decisions.

To study the regeneration dynamics in mature black pine (Pinus nigra Arn.) plantations in the Middle Balkan Range, Bulgaria, a total of 48 research plots (sized 0.1 ha) were established ; 26 plots were established in the foothills of the mountains (foothill zone) and 22 in the main massive (mountainous zone). Pine overstorey as well as advance regeneration in subplots were recorded. Analysis of variance and regression analysis showed that in general relative stand basal area (RSBA) was the most important predictor of deciduous advance regeneration density, top height as well as age span of the regeneration layer. In the mountainous zone soil depth (SD) and the presence of mature deciduous trees (MDT) explained a significant amount of the variation in regeneration features. Lower RSBA induced by earlier thinnings resulted in higher regeneration density, larger top heights and wider age span of deciduous species. Under the pine canopy oak regeneration can persist longer compared to natural broadleaved canopies. In the studied plantations pine regeneration was confined to few scattered seedlings and regeneration groups. Based on these findings silvicultural concepts for the further management of black pine plantations in the Middle Balkan Range are discussed.

International audience; This study compiles and summarizes the existing knowledge about observed and projected impacts of climate change on forests in Europe. Forests will have to adapt not only to changes in mean climate variables but also to increased variability with greater risk of extreme weather events, such as prolonged drought, storms and floods. Sensitivity, potential impacts, adaptive capacity, and vulnerability to climate change are reviewed for European forests. The most important potential impacts of climate change on forest goods and services are summarized for the Boreal, Temperate Oceanic, Temperate Continental, Mediterranean, and mountainous regions. Especially in northern and western Europe the increasing atmospheric CO2 content and warmer temperatures are expected to result in positive effects on forest growth and wood production, at least in the short–medium term. On the other hand, increasing drought and disturbance risks will cause adverse effects. These negative impacts are very likely to outweigh positive trends in southern and eastern Europe. From west to east, the drought risk increases. In the Mediterranean regions productivity is expected to decline due to strongly increased droughts and fire risks. Adaptive capacity consists of the inherent adaptive capacity of trees and forest ecosystems and of socio-economic factors determining the capability to implement planned adaptation. The adaptive capacity in the forest sector is relatively large in the Boreal and the Temperate Oceanic regions, more constrained by socio-economic factors in the Temperate Continental, and most limited in the Mediterranean region where large forest areas are only extensively managed or unmanaged. Potential impacts and risks are best studied and understood with respect to wood production. It is clear that all other goods and services provided by European forests will also be impacted by climate change, but much less knowledge is available to quantify these impacts. Understanding of adaptive capacity and regional vulnerability to climate change in European forests is not well developed and requires more focussed research efforts. An interdisciplinary research agenda integrated with monitoring networks and projection models is needed to provide information at all levels of decision making, from policy development to the management unit.