Implementing the 2% wilderness goal in Germany – The National Natural Heritage Site Rechlin as a case study

The European Union aims to increase the extent of strictly protected areas, including wilderness areas. However, operationalizing this goal in densely populated Central European member states like Germany, that consists almost entirely of cultural landscapes and will need to rely largely on secondary wilderness areas, is challenging. Anthropogenic influence should be minimized in wilderness areas to support species that depend on undisturbed ecosystems shaped by natural processes. Based on a literature review, we developed a set of criteria to assess the spatial and legal suitability of potential wilderness areas, evaluate their ecological condition and measure the magnitude of human impact. We used available datasets to apply those criteria to a potential wilderness area (PWA), the National Natural Heritage Site Rechlin. From the 20 criteria identified, 12 could be assessed using available datasets, including fragmentation, connectivity, naturalness, habitat continuity and anthropogenic pollution. The PWA Rechlin comprises an area of 1349 ha that is traversed by 9 km of major public roads and waterways; and further fragmented by 81 km of unpaved forest paths. Most of the area is forest (89%), dominated by plantations of the allochthonous species Pinus sylvestris and Picea abies (84%). The majority of forest stands are in the establishment (45%) and early optimum stage (41%). Emissions of nitrogen and phosphorous have caused the eutrophication of two lakes within the candidate site and may affect the potential for natural regeneration of Asperulo-Fagetum forest. Although the NNHS Rechlin does not comply fully with fragmentation and naturalness criteria, the site could be considered for a future wilderness area, especially given the limited availability of other suitable sites in Germany.