Emilie Isasa

Emilie Isasa

PhD student

Address:

Botanik II - Ecophysiology and Plant Ecology

Julius-von-Sachs-Platz 3, 97082 Würzburg

Tel: +49 931 31-80845

eMail:  emilie.isasa@uni-wuerzburg.de

Project: Drought-stress resistance of native and non-native broadleaved tree species

I´m working in a joint project between Ecosystem Modeling (CCTB) and the Department of Ecophysiology and Plant Ecology. In the scope of climate warming and the increase in frequency and intensity of severe heat waves in Central Europe, identification of temperate tree species that are suited to cope with these environmental changes is gaining increasing importance. Although several tree physiological attributes are related to drought-stress resistance and survival after severe heat, recent studies highlight the importance of plant hydraulic traits for predicting drought-induced tree mortality and their potential to forecast species’ distribution in a changing climate. However, most plant hydraulic traits are labour-intense and prone to measurement artefacts, hindering the compilation of large global datasets and their integration into predictive models. To fill this gap, a set of plant functional traits related to drought survival will be measured for 50 native and non-native temperate broad-leaved tree species, including structural, hydraulic, anatomical, and foliar traits. These tree species are part of the initiative ‘Stadtgrün 2021’ by the Bavarian State Institute for Viticulture and Horticulture (LWG). We will characterise the drought-stress resistance of the species sample and search for trade-offs between vascular, hydraulic and foliar traits. I will further calibrate mechanistic models with these functional traits to predict structural characeristics as well as the growth and performance of trees under scenarios of future climate. The mechanistic models will be also used to reconstruct evolutionary pathways to identify what traits or trait syndromes jointly co-evolved due to changing environmental conditions.

The project has 3 main objectives:

1. Compiling Compile a set of plant functional hydraulic traits for a high number of native and non-native temperate broad-leaved tree species. Classify the drought-stress resistance of the species sample and search for trade-offs between vascular, hydraulic and foliar traits.
2. Assessing whether currentCalibrate structurally-realistic mechanistic models can be calibrated with easily accessible plant functional traits that are suited to predict the hydraulic trait of interest. Applying the calibrated model to increased temperature and drought to assess tree performance under environmental change.
3. Quantify phylogenetic signals in traits by comparing molecular phylogenetic trees with evolutionary pathways for trait syndrome evolution across species based on parameterization pathways of the mechanistic model.