Modelling of the impacts of climate change on the flora of Germany | Umweltbundesamt

Modelling will be based on the distribution of plant species in Germany, using the FLORKART database. Climate and land use parameters, relevant geological and soil factors, and bioecological data from the BiolFlor database will be included. First, a classification of climate elements into so-called multidimensional climate areas will be carried out. In these climate areas, plane table sheets will be grouped according to the similarity of climate parameters. Based on statistics, the individual species will be assigned according to their climate areas. The projection of the territorial shifts will assume three different climate change scenarios (+ 2°C, + 3°C and + 4°C; see also ALARM project). In this way, the assignment of the plane table sheets to the climate areas changes. Using statistical methods such as Generalized Linear Models (GLM), Generalized Additive Models (GAM) as well as Artificial Neural Networks (ANN), and taking the species pool concept into account, the potential distribution areas or territories of the flora in Germany can then be modelled, based on the projected new climate areas.

drier summers, wetter winters

The potential distribution territories of plants (and animals) are limited by climatic factors such as temperature and precipitation. In addition, the distribution of a species is further restricted, for example due to land use changes, nutrient supply and competition. In recent years, territorial shifts have been observed in plants, such as the Holly, towards the north east - in parallel with a rise in temperatures, which can be attributed to climate change.

Among other things, the outcome of the project is that natural systems are already being affected today by the anthropogenic climate change, although nature conservation efforts and changes in land use can mask these climate signals in some territories. Assuming a moderate climate change progression of around + 2.2°C by 2080, about 60% of the species in Germany will face a depletion of suitable distribution territories in the future. A decline in the indigenous species, and improved conditions for foreign species, will result in changes of the local species diversity. Furthermore, the analyses revealed that the greatest changes to the species pool would occur in East and South-West Germany, as the model showed a complete loss of suitable territory in these regions for some of the tested species.

Depending on land use, as well as biology, ecology and distribution of plant species, territorial shifts have already occurred. There is an urgent need for action whenever such territorial shifts lead to a significant reduction in the overall distribution area of a species.