The Natura 2000 network of the European Union (EU) aims at protecting endangered species and habitats. Under climate change, conservation efforts are challenged in a new dimension. Conservation targets might lose their representation within the network due to distribution shifts in response to abiotic changes. Forest ecosystems are especially vulnerable in this context. Their long life spans and slow migration responses impede the dispersal to locations of future environmental suitability. This study investigated the exposure of three priority forest habitat types to climate change, namely (1) Tilio-Acerion forests of slopes, screes and ravines, (2) bog woodlands and (3) alluvial forests with Alnus glutinosa and Fraxinus excelsior. We classified exposure by the means of projected range size, range change and estimated coverage by protected areas.
Material and Methods
We combined ensembles of species distribution models with spatial analyses on Bavarian scale to assess the ability of Natura 2000 sites to accommodate the forest types in 2061-2080. We considered two climate change scenarios (“Representative Concentration Pathway” RCP4.5 and RCP8.5) of the HadGEM2-ES circulation model as realistic future developments. Climatic variables, soil parameters and topography served as environmental predictors.
According to our results, bog woodlands are most vulnerable to climatic changes, followed by Tilio-Acerion forests of slopes, screes and ravines. Alluvial forests with Alnus glutinosa and Fraxinus excelsior behave in a less sensitive manner. While modelled range size development and protected area coverage vary among the habitat types, the outcomes suggest a common aggravation of both under RCP8.5 in comparison to RCP4.5.
We argue that conservation efforts should focus on climate change mitigation, more vulnerable habitat types and the adaptation of the Natura 2000 network.