Forests under stress: Impact of global warming and drought stress on tree hydraulic architecture and vulnerability to embolism

Alberto Vilagrosa

Center for Environmental Studies in the Mediterranean (CEAM) & Dept. Ecology
Alicante University

Fellowship Period: 08.2019-10.2019

Research interests and main activities

The main research interest is plant ecophysiology in water limited environments with applications to the ecological restoration of degraded ecosystems in Mediterranean areas. Within this field of research, I developed studies in ecophysiological factors limiting survival of species in restoration projects and also seedling quality and responses to nursery treatments (fertilization, drought preconditioning, root system development, etc.). Currently, my studies are focused to understand processes in forest decline, plant plasticity to adapt future conditions and ecohydrological processes related to these changes such as use of water by vegetation and vulnerability to drought conditions.



Activities within WSL Fellowship

In recent years, a big concern has arisen over large-scale climate-induced reductions in forest growth and survival. Specifically, the increased drought frequency under higher temperatures (known as “hotter-droughts” or “global change-type droughts”) has been related to irreversible changes in terrestrial ecosystem functions and structures, including phenomena of massive tree mortality in forests around the globe. However, mechanisms of tree mortality, survival and acclimation to projected climate mainly affecting the hydraulic properties of trees (i.e. xylem cavitation and embolism) are far from being understood. Therefore, the objective of my fellowship at WSL was to analyze tree vulnerability to embolism and acclimation potential of several hydraulic parameters in response to hotter droughts. The main questions addressed during my visit are: i) Which are the mechanisms of hydraulic acclimation to drought and warming conditions in trees?, ii) Are these mechanisms showing a common patterns of response among species or are they related to the functional strategy of plants (i.e. conifers vs. deciduous species), iii) Are the acclimation mechanisms mainly governed by soil moisture or temperature effects during hotter droughts?

Improving our understanding of the physiological mechanisms by which forests respond to climate variability and providing strong process-based knowledge for the implementation of dynamic vegetation models is a common goal that we share in our research.

My stay at WSL was a very nice experience, professionally and also personally. WSL at Birmensdorf provide great opportunities to develop a research career and it is located very close to the nice city of Zurich  and its fantastic lake. In general, Switzerland offers a large amount of opportunities to visit interesting places and mountain trips.

Cooperation within WSL

Interne Kontakte (Datensätze)

Cooperation outside of WSL