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.

-In order to analyze the growth dynamics of beech seedlings growing under contrasting canopy conditions, a beech stand in which two types of canopy opening (canopy release or gap creation) had been applied in 1995 was selected. Three and four years after the canopy had been opened, 113 naturally regenerated seedlings were sampled in gaps or under the canopy. The effects of canopy opening and seedling age on annual height and diameter growth were analyzed using mixed models. Under closed canopy, average annual seedling height and diameter increments were 1.2 cm and 0.18 mm, respectively. Diameter growth increased in the first year after the canopy had been opened, and exhibited considerable inter-annual variation related to climatic conditions. Conversely, height growth did not increase immediately after canopy opening, but increased regularly in the following years. Four years after the gap had been created, annual seedling height and diameter growth were 9.5 cm and 0.49 mm respectively in the gaps, and 3.8 cm and 0.21 mm respectively under released canopy. Age did not affect the dynamics of seedling growth.gap / shade tolerance / natural regeneration / Fagus sylvatica L. / mixed model Résumé -Effets de l'ouverture du couvert sur la croissance en hauteur et en diamètre de semis naturels de hêtre. La dynamique de croissance de jeunes semis de hêtre poussant dans les conditions de couvert contrastées a été étudiée dans un peuplement à base de hêtre dans lequel deux types d'ouverture du peuplement ont été réalisés. En 1995, un simple relevé de couvert a été effectué dans l'ensemble du peuplement et des trouées ont été ouvertes dans certaines parties. En 1998 et 1999, 113 semis naturels de hêtre ont été récoltés sous couvert ou dans les trouées. Les effets combinés de l'ouverture du couvert et de l'âge des semis sur la croissance en hauteur et en diamètre des semis ont été analysés à l'aide de modèles linéaires mixtes. Les semis sous couvert présentaient un accroissement annuel en hauteur de 1,2 cm et un accroissement annuel en diamètre de 0,18 mm. La croissance en diamètre a augmenté dès la premère année après l'ouverture du couvert et a ensuite montré de fortes variations inter-annuelles liées à des variatons climatiques. En revanche, l'augmentation de la croissance en hauteur à la suite de l'ouverture du peuplement n'a pas été immédiate, et a continué de manière progressive dans les quatre années suivantes. Quatre ans après l'ouverture du peuplement, les accroissements annuels en hauteur en en diamètre étaient de 9,5 cm and 0,49 mm respectivement pour les semis dans les trouées et de 3,8 cm and 0,21 mm respectivement pour les semis sous relevé de couvert. La croissance des semis n'est pas apparue liée à l'âge. trouée / tolérance à l'ombrage / régénération naturelle / Fagus sylvatica L. / modèle mixte

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We studied the interaction of light and water on water-use efficiency in cork oak (Quercus suber L.) seedlings. One-year-old cork oak seedlings were grown in pots in a factorial experiment with four light treatments (68, 50, 15 and 5% of full sunlight) and two irrigation regimes: well watered (WW) and moderate drought stress (WS). Leaf predawn water potential, which was measured at the end of each of two cycles, did not differ among the light treatments. Water-use efficiency, assessed by carbon isotope composition (delta(13)C), tended to increase with increasing irradiance. The trend was similar in the WW and WS treatments, though with lower delta(13)C in all light treatments in the WW irrigation regime. Specific leaf area increased with decreasing irradiance, and was inversely correlated with delta(13)C. Thus, changes in delta(13)C could be explained in part by light-induced modifications in leaf morphology. The relationship between stomatal conductance to water vapor and net photosynthesis on a leaf area basis confirmed that seedlings in higher irradiances maintained a higher rate of carbon uptake at a particular stomatal conductance, implying that shaded seedlings have a lower water-use efficiency that is unrelated to water availability.

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The aim of the study was to investigate dynamics and pattern of natural regeneration and the influence of seedbed and light on germination and initial seedling survival of Scots pine (Pinus sylvestris L.) during three growing seasons. Four 5-m 2 plots in a natural Scots pine forest in central Spain were randomly established at the beginning of the regeneration process. Germination and seedling survival were recorded in 100 regeneration sampling subplots (0.25 m 2 ) per plot, while seedbed type and the relative light intensity reaching the forest floor was characterised in 1-m 2 subplots. The spatial correlations between survival, light conditions and organic matter depth were analysed through crossvariograms. Germination and survival were highly variable both within and between plots (ranging from 0 to 89%) and affected by high summer temperatures (33-35°C) in 2003. The spatial pattern characterisation of survival by Ripley's K function showed a dominant cluster distribution. Occurrence tended to be clumped when abundance was greater than 15 seedlings, whereas for lower densities, seedlings were randomly distributed. Seedlings and herbs occupied the same sites where environmental conditions were appropriate for them to live. Spatial association occurred frequently for light and organic matter depth. Results suggested that the Scots pine seedlings in our study in central Spain preferred moderate light conditions (Global Site Factor <0.40). Thus, if this forest is to be naturally regenerated with Scots pine, the shelterwood system (whereby some mother trees are left to provide shelter for at least 5 years), along with mechanical disturbance of the seedbeds, would promote seed germination, as long as a seed source is present. However, regeneration success is affected by year-to-year conditions.

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