Dynamic vegetation models for climate-dynamic suitability testing of main and secondary tree species in Baden-Württemberg (DynaVeg)

Research question
Due to climate change, our forests are expected to change fundamentally in the coming decades. Reliable predictions about what the forests of the future are likely to look like hardly exist. In this context, the central question in the project is: Which trees will be able to survive under future climate conditions, grow well and be competitive with other tree species?
 

Fig. 1: Mixed forest with fir growth in the Ortenau district. Will such forests be stable under changing climatic conditions?  Photo ©N. Kühl

Objective
The project aims to assess the future potential of currently important species in our forests under predicted climate conditions and to explore the potential of alternative tree species. The project focuses on the one hand on those tree species that have been of great importance in the forests of Baden-Württemberg in the past as well as today, and on the other hand on tree species that may be better adapted to the changing climate conditions but are not yet of great importance.
The tree species we plan to study include Corylus sp. (hazel), Castanea sativa (sweet chestnut), service tree, spruce, downy oak, copper beech, holm oak, English oak, sessile oak, Scots pine and silver fir.


Method
We use the dynamic vegetation model "LandClim", developed at the ETH Zürich, to simulate the potential tree species composition in the years 2050 and 2100 for two different climate scenarios (RCP 4.5 and RCP 8.5). That is, one simulation for the moderate scenario (warming by +2.6 °C compared to the pre-industrial temperature) and one simulation for the "continue-as-before" scenario (warming by +4.8 °C compared to the pre-industrial temperature). The simulation model integrates, for example, plant demographic processes such as reproduction, dispersal, growth, competition and mortality.


Fig. 2: Dynamic vegetation model/scheme of modeling: Spatially high-resolution environmental data, tree species characteristics (e.g., distribution type, mortality rate), and their relationship to the environment (e.g., to temperature) form the basis on which the model simulates, amongst others, biomass and tree species composition over time. / Graphic: Uni Freiburg & FVA


The advantage of this dynamic modeling is that not only average climate values are included in the calculation, but also extreme events. The predicted change in the probability of occurrence of extreme events - for example, periods of drought and an increase in the risk of fire - is also taken into account. The effect of different forest management practices can also be simulated. This makes allows to estimate the effect of planned measures.

Project members
The project is carried out in cooperation of the university of Freiburg and the Forest Research Institute of Baden-Württemberg (FVA Baden-Württemberg). Project members are  PD Dr. Norbert Küh at the University of Freiburg, and Dr. Axel Albrecht (coordinator), Helena Böddeker and Dr. Christopher Traiser at the FVA Baden-Württemberg.


Further information:
=> https://www.fva-bw.de/abteilungen/waldwachstum/notfallplan-projekte/dynamische-vegetationsmodelle