RT Journal Article T1 Carbon carrying capacity in primary forests shows potential for mitigation achieving the European Green Deal 2030 target A1 Keith, Heather A1 Kun, Zoltàn A1 Hugh, Sonia A1 Svoboda, Miroslav A1 Mikoláš, Martin A1 Adam, Dusan A1 Bernatsk, Dmitry A1 Blujdea, Viorel A1 Bohn, Friedrich A1 Camarero, Jesús Julio A1 Demeter, László A1 Di Filippo, Alfredo A1 Dutcă, Ioan A1 Garbarino, Matteo A1 Horváth, Ferenc A1 Ivkovich, Valery A1 Jansons, Āris A1 Ķēņina, Laura A1 Kral, Kamil A1 Martin-Benito, Dario A1 Molina-Valero, Juan Alberto A1 Motta, Renzo A1 Nagel, Thomas A. A1 Panayotov, Momchil A1 Pérez Cruzado, César A1 Piovesan, Gianluca A1 Roibu, Cătălin-Constantin A1 Šamonil, Pavel A1 Vostarek, Ondřej A1 Yermokhin, Maxim A1 Zlatanov, Tzvetan A1 Mackey, Brendan K1 Carbon cycle K1 Climate-change ecology K1 Climate-change mitigation K1 Forest ecology AB Carbon accounting in the land sector requires a reference level from which to calculate past losses of carbon and potential for gains using a stock-based target. Carbon carrying capacity represented by the carbon stock in primary forests is an ecologically-based reference level that allows estimation of the mitigation potential derived from protecting and restoring forests to increase their carbon stocks. Here we measured and collated tree inventory data at primary forest sites including from research studies, literature and forest inventories (7982 sites, 288,262 trees, 27 countries) across boreal, temperate, and subtropical Global Ecological Zones within Europe. We calculated total biomass carbon stock per hectare (above- and below-ground, dead biomass) and found it was 1.6 times larger on average than modelled global maps for primary forests and 2.3 times for all forests. Large trees (diameter greater than 60 cm) accounted for 50% of biomass and are important carbon reservoirs. Carbon stock foregone by harvesting of 12–52% demonstrated the mitigation potential. Estimated carbon gain by protecting, restoring and ongoing growth of existing forests equated to 309 megatons carbon dioxide equivalents per year, additional to, and higher than, the current forest sink, and comparable to the Green Deal 2030 target for carbon dioxide removals. PB Springer Nature YR 2024 FD 2024 LK https://hdl.handle.net/10347/40635 UL https://hdl.handle.net/10347/40635 LA eng NO Keith, H., Kun, Z., Hugh, S. et al. Carbon carrying capacity in primary forests shows potential for mitigation achieving the European Green Deal 2030 target. Commun Earth Environ 5, 256 (2024). https://doi.org/10.1038/s43247-024-01416-5 NO We thank the many people involved with the collection and provision of the site data and recognise the significant resources, people and time required to collect this invaluable data. The research for the synthesis, analysis and writing (H.K., Z.K., S.H., B.M.) was supported by a grant from a charitable organisation which neither seeks nor permits publicity for its efforts. The funder had no involvement in the study design, results or publication of the paper. Site data from Spain was funded by the Spanish Ministry of Science, Innovation and Universities [AGL2016-76769-C2-2-R]. C.P.C. was supported by the Spanish Ministry of Science and Innovation [RYC2018-024939-I]. J.A.M.V. was supported by the Ramón Areces Foundation Grants for Postdoctoral Studies. Contribution of D.A., K.K. and P.S. as well as data collection and processing from Czech natural forests was supported by Czech Science Foundation, project no. 24-11119S. D.M.-B. was funded by projects AGL2015-73190-JIN, PID2019-110273RB-I00 and contract RYC-2017-23389 by the Spanish Ministry of Science and Innovation MCIN/AEI. V.B. and I.D. were supported by the FORCLIMIT project funded in the frame of the ERA-NET FACCE ERA-GAS and with national support from Romanian National Authority for Scientific Research and Innovation, CCCDI – UEFISCDI [grant number 82/2017]. FACCE ERA-GAS has received funding from the European Union’s Horizon 2020 research and innovation programme [grant agreement 696356. T.Z. was funded by The WWF Bulgaria through the project IKEA № 9E0710.05 and by The National Roadmap for Research Infrastructure (2020-2027), Ministry of Education and Science of Republic of Bulgaria, through agreements No DO1-405/18.12.2020 and DO1-163/28.07.2022 (LTER-BG). L.D. was funded by the project of the National Research, Development and Innovation Office NKFIH K 131837. T.N. received support from the Slovenian Research Agency (Project No. J4-1765). For additional assistance with site data, we thank Dr. Raúl Sanchez-Salguero and Dr. Andrea Hevia for evaluating the age in the dendrochronological samples in Spain, and Nesibe Köse, Mehmet Doğan, Daniel Bishop, Marco Mina, Timothy Thrippleton, Neil Pederson, Guillermo Gea-Izquierdo and Macarena Férriz for their help during fieldwork, and Cengiz Cihan and the Turkish General Directorate of Forestry (OGM) in Borçka (Artvin) for their assistance in the field in Turkey. DS Minerva RD 28 abr 2026