Project Details
Projekt
Understanding the effect of belowground hydrological processes and inter-individual interactions on tree water stress using coupled ecohydrological–plant hydraulic modelling
Applicant
Professor Dr. Ilhan Özgen
Subject Area
Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
Term
since 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 545756575
As seen in the recent drought-induced forest dieback and growth reduction in Europe and around the world, climate change has a devastating effect on forest ecosystems. Therefore, new strategies for stabilising existing forests are urgently needed. A key challenge for forest management is that most predictions rely on drought stress estimation in forests using simplified approaches at the stand scale, thereby neglecting different potentially important belowground processes. This project investigates the effect of two such belowground processes—(i) deep water dynamics and (ii) species mixture—on the resilience of forest ecosystems to water stress using coupled ecohydrological–plant hydraulic modelling, constrained by field data of stable water isotopes, tree water stress, and sapflow collected in this project, and through synergies with ongoing projects from Germany and France. The novelty of this coupled model is its emphasis on drought-related processes in both the plants and the soil. The project consists of four work packages (WPs), led by four working groups (two in Germany and two in France). The first WP will leverage stable water isotope measurements to study belowground processes in the field. These measurements will be used to inform and validate the computational models that will be developed in the second and third WPs. In addition, data collected in ongoing research projects will be used to inform the modelling. The second WP will couple an ecohydrological and a plant hydraulic model to investigate topographic controls on deep water in a spatially distributed manner. The third WP will develop a multispecies plant hydraulic model to study the effect of species mixture on forest drought resilience. Finally, the fourth WP will carry out a detailed model-based case study in Vosges Mountains, France, where both topographic controls and inter-individual competition are hypothesised to play a major role on tree mortality patterns. The project will deliver valuable insights into two underexplored components of forest drought resilience and provide a novel computational tool in the form of the coupled ecohydrological–plant hydraulic model for future drought studies. Further, we expect this project to strengthen the collaboration between the French and German groups, which we envision to result in future joint research endeavours.
DFG Programme
Research Grants
International Connection
France, Spain
Partner Organisation
Agence Nationale de la Recherche / The French National Research Agency
