Evaluating spatially explicit carbon-neutrality for boreal landscapes and regions

The challenges posed by climate change, biodiversity loss and harmful land-use are deeply interconnected. Successful co-managing of these drivers requires innovative methods that can prioritize and target management actions against multiple criteria, while also enabling evaluation of greenhouse gas (GHG) emissions from different sources and integrated land use planning. The EU aims at reaching carbon neutrality by 2050 and Finland by 2035. We have conducted spatially explicit integrated modelling and evaluation in boreal landscapes and regions in Finland, considering national climate and biodiversity targets and sustainable forestry strategies. Results of three spatially distributed model systems (FRES, PREBAS, Zonation) were integrated to evaluate the potential to reach these goals at both national and regional scale in Finland, by simultaneously considering protection targets of the EU biodiversity strategy. We used different spatial databases and scenarios until 2050 based on mitigation measures of the national climate and energy strategy, forestry policies and predicted climate change. We then evaluated how implementation of these scenarios would affect GHG fluxes, carbon storages, and the possibility to reach the carbon neutrality target (Fig. 1 , Forsius et al. 2023, Holmberg et al. 2023, Junttila et al. 2023). Forested areas important for biodiversity protection were identified based on spatial prioritization. The policy-relevant aim has been to provide detailed spatial, scenario-based information at different scales for key end-users (e.g., communities, provinces, forestry districts, ministries, Alam et al. (2023)). This information can be used for e.g., regional land-use and energy strategy planning/management, and sustainability assessment. We have used data from eLTER/ICOS sites for model developments and evaluation (Forsius et al. 2021). Key general conclusions from our studies are: The potential to reach carbon neutrality in the different administrative regions in Finland varies widely. Reaching both the national and most regional carbon neutrality targets by 2035 assuming current forest harvesting levels is challenging. Integrated evaluation of biodiversity and climate targets enables development of cost-efficient measures. Carbon sequestration of forests is enhanced with climate change, but uncertainties caused by disturbances increase also. The potential to reach carbon neutrality in the different administrative regions in Finland varies widely. Reaching both the national and most regional carbon neutrality targets by 2035 assuming current forest harvesting levels is challenging. Integrated evaluation of biodiversity and climate targets enables development of cost-efficient measures. Carbon sequestration of forests is enhanced with climate change, but uncertainties caused by disturbances increase also. Key aims for future work are to develop process descriptions in our model systems, conduct uncertainty modelling and assessment, and continue co-operation with regional actors to evaluate regional targets.