Acclimation and Mortality: European Forest Response to Increasing Drought Stress (ARiD)

• Applicant: Dr. Edurne Martinez del Castillo
• Subject Area: Forestry ; Physical Geography
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 539441548

The recent increase in drought frequency and persistence challenges the acclimation capacity of many tree species and causes widespread productivity declines and dieback across European forests. The accelerated speed of these processes questions long-standing management practices and demonstrates the need to reconstruct and model growth and stand dynamics under changing boundary conditions. Here, I propose to analyze inter-regional climate-growth responses to model the resilience and acclimation of trees under future climate conditions. The analysis is centered on one of the most important forest species in central Europe (Pinus sylvestris L.) and will be upscaled to its distribution range. I will focus on the relationship between xylem anatomy and climate variability before, during, and after past drought events to derive statistically validated estimates of pine acclimation capacity using a tree-ring network of living and dead trees in central Europe. Within the project, 17 new forest locations will be sampled, measurements from 20 more sites updated, and data of more than 300 analyzed sites used. Generalized linear mixed models (GLMM) are used to upscale acclimation capacity estimates and develop spatially distinct suitability projections for European pine stands considering different pathway scenarios of climate modeling. The project will deliver (i) a new sub-continental dendrochronological network of living and dead trees to derive statistical metrics for drought-impact assessment, (ii) quantification of Pinus sylvestris acclimation capacity in central Europe and beyond, and (iii) spatially resolved estimates of future forest suitability and resilience under varying climate change scenarios up to the year 2100. The integration of widespread empirical data from hundreds of tree-ring sites and state-of-the-art modelling will be essential to evaluate forest performance across a wide range of natural environments in Europe. This approach will provide insights to address global change research questions with major ecological and socio-economic repercussions. The project will thereby contribute to ongoing efforts to develop sustainable forestry strategies under changing climate.

• DFG Programme: Research Grants