"Forests in SW Europe could experience in the near future important changes in climate but also in forest management, which is moving from focusing on timber production to consider values such as bioenergy, carbon sequestration, biodiversity and others. These factors could change inter-specific competition in Scots pine/European beech mixedwoods, which cover important areas in SW Europe, altering growth and yield dynamics of these stands. The objectives of this project are: 1) To characterize current trends and estimate future trends of Pinus sylvestris and Fagus sylvatica growth in mixedwoods at stand level to support sustainable forest management plans; 2) To develop, evaluate and apply reliable ecologically-based mathematical models to support ecological research on interactions among tree species and their environment that can be applied in forest management. To achieve these objectives the project will be implemented in three stages: 1) Field data form experimental plots in mixed Scot pine and European beech stands in the Pyrenees will be collected to estimate the magnitude of biomass and nutrient pools in the canopy, understory and soil. Nutrient cycles will be characterized assessing litter and coarse woody debris production, decomposition rates, and tree growth rates. A greenhouse study will provide information on germination rates and (combined with field measurements) photosynthetic efficiency. Water-related physical soil properties will be studied to assess the importance of water limitation in these stands. 2) The ecosystem model FORECAST-Climate will be calibrated with the field data collected, and its performance evaluated with dendroclimatological records of the historical patterns of climate-tree growth relationships. 3) A battery of scenarios of climate change and forest management will be simulated to assess their long-term consequences on these forests and provide guidelines on the changes and potential consequences of each management option."