Project Details
Projekt
SP05: Whole-tree hydraulic performance in two temperate broadleaved species differing in stomatal behaviour
Applicant
Professor Dr. Bernhard Schuldt
Subject Area
Forestry
Ecology and Biodiversity of Plants and Ecosystems
Ecology and Biodiversity of Plants and Ecosystems
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 538902328
Forests provide various ecosystems services but are increasingly threated by climatic extremes. For understanding the drought responses of woody plants, continuous field data on their water status of mature trees are needed. Therefore, the project will combine classic eco-physiological techniques and approaches with novel technical developments to monitor whole-tree hydraulic performance in two forest tree species with contrasting stomatal regulation of leaf water potential. The species sample includes mature trees of anisohydric beech (Fagus sylvatica L.) and isohydric small-leaved lime (Tilia cordata MILL.), which will be measured on sandy and loamy forest soils in lower Franconia, one of the driest regions in Germany. We will apply a combination of automated sensor-based measurements with manual gas-exchange measurements in the upper-most canopy, accompanied by different root sampling campaigns. We speculate that fine root characteristics, vertical rooting patterns, and soil-root connectivity, as assessed by sap flow measurements in small diameter roots, are mainly responsible for the observed patterns of seasonal differences in canopy level stomatal behaviour between anisohydric and isohydric tree species. By continuously monitoring soil, stem and branch water potential in coordination with gas exchange and sap flow measurements, we will be able to contribute to the major questions of the SOPHY research unit. These relate plant transpiration to changes in leaf and soil water potentials, contribute to the identification of key hydraulic limits to water flow, and explore which changes in soil-plant hydraulic conductance ensure linearity on a diurnal and growth season scale.
DFG Programme
Research Units
