Human transformation of ecosystems: Comparing protected and unprotected areas with natural baselines

Protected areas serve as reserves of biological diversity and conserve the naturalness of characteristic regional ecosystems. Numerous approaches have been applied to estimate the level of transformation of ecosystems and to compare trends inside and outside of protected areas. In this study, we apply aggregate indicators of anthropogenic pressures on ecosystems and biodiversity in a fine-scale spatial analysis to compare the level of human influence within protected and unprotected areas. The actual state of ecosystems is compared to a natural baseline that is intact or potential natural state. The results show that in a non-protected Central-European landscape, humans appropriate a considerable share of natural ecosystem productivity and carbon stocks, and significantly reduce natural biodiversity and ecosystem services. Human appropriation of net primary production reached more than 60% in total, humans reduced original biodiversity levels by 69%, and net carbon storage was considerably decreased by intensive types of land use. All three indicators significantly differed between protected areas and unprotected areas, suggesting that protected areas maintain higher biodiversity levels, store more carbon and are in total less influenced by human exploitation than average non-protected landscape. Furthermore, we bring evidence that human appropriation of net primary production is negatively related both to biodiversity and ecosystem services indicated by mean species abundance and net carbon storage at the national level. Our results contribute to the quantitative evidence of the impacts of anthropogenic transformation of natural ecosystems on the ecosystem condition, supporting the hypothesis that protected areas significantly reduce anthropogenic pressures and contribute to maintaining critical ecosystem services and biodiversity.