Forest restoration under the EU Nature Restoration Regulation: Implications for biodiversity and ecosystem service trade-offs

The EU Nature Restoration Regulation (NRR) aims to shift forest ecosystems towards increased naturalness, with long-term benefits for biodiversity. Here we model two scenarios of restoration in a southern Swedish production forest landscape, combining the re-establishment of forest habitat types with management practices of reduced intensity. We analyze temporal developments in key biodiversity indicators outlined in Article 12 of the NRR and compare them with a business-as-usual forest management scenario. In addition, we examine long-term effects of restoration on aboveground carbon storage, timber provisioning, bilberry supply, aesthetic value, habitat maintenance, and ecosystem service multifunctionality. Restoration scenarios increased aboveground biomass, bilberry supply, habitat maintenance, and aesthetic value compared with business-as-usual management, but resulted in moderate reductions in timber provisioning. Moreover, restoration promoted a more even spatial distribution of ecosystem services, leading to a more diverse and multifunctional supply of ecosystem services. Our results show that assessments of biodiversity change are strongly influenced by indicator design. In the business-as-usual scenario, increases in mean landscape-level deadwood supply occurred simultaneously with declines in the area of deadwood-rich habitat, indicating that coarse-scale aggregated indicators may mask losses of high-quality habitat. This highlights the importance of combining complementary monitoring approaches that capture both spatial changes in habitat quality and broader landscape trends when evaluating restoration progress and NRR compliance. Overall, the results demonstrate that ambitious forest restoration can provide long-term enhancement of biodiversity indicators and lead to increased ecosystem service supply in hemiboreal production forest landscapes.