Exploring monitoring and management strategies towards european forests multifunctionality

In light of current European EU policies, such as the Biodiversity and Forest strategies for 2030, this work highlights the inherent complexity in achieving multifunctionality in European forests. Biodiversity conservation, timber production, and climate change mitigation are among the most crucial functions currently required from forest ecosystems. In this thesis I contributed to a harmonized, Europe-wide database of forest multi-taxon biodiversity and stand structure in the framework of COST Action CA18207 “Bottoms-Up”, enabling a comprehensive analysis of the trade-offs and feasibility of integrating these three major functions. Using this dataset, I explored four main objectives: (1) assess whether carbon and biodiversity policies have the potential for a win-win outcome at the stand scale, finding that aboveground carbon storage alone does not consistently support multi-taxon biodiversity, while positive biodiversity-carbon relationships depend largely on deadwood carbon pools for taxa like wood-inhabiting fungi and saproxylic beetles; (2) evaluating how individual species within three taxonomic groups—vascular plants, bryophytes, and lichens—respond to different silvicultural regimes, which showed that species responses to management are highly variable and often challenge conventional management approaches; (3) identifying structural attributes that support species richness in Mediterranean forests, specifically deadwood quality, canopy openness, and basal area, thus underscoring the unique ecological conditions in these underrepresented ecosystems; and (4) analyzing the completeness of in-situ biodiversity data across taxonomic groups, revealing substantial variation in sampling effort requirements by group and region. This research underscores the challenge of achieving biodiversity conservation, timber production, and climate mitigation within the existing policy framework in European forests. We stress the flaws of a one-size-fits-all approach given the diverse ecological needs and species-specific responses observed across forest types and silvicultural systems. These findings emphasize the importance of adaptive, comprehensive strategies tailored to different forest ecosystems. To ensure sustainable forest landscapes that balance these essential functions, it is crucial to integrate policy objectives with detailed ecological knowledge. Looking forward, enhanced monitoring strategies across Europe are essential to address data gaps, enabling management approaches that support long-term forest resilience and multifunctionality