Forest degradation contributes more to carbon loss than forest cover loss in North American boreal forests

• Main Authors: Yu, Ling, Fan, Lei, Ciais, Philippe, Xiao, Jingfeng, Frappart, Frédéric, Sitch, Stephen, Chen, Jingming, Xiao, Xiangming, Fensholt, Rasmus, Chang, Zhongbing, Fang, Hongqian, Li, Xiaojun, Cui, Tiangxiang, Ma, Mingguo, J.-P., Wigneron
• Other Authors: Southwest University Chongqing, Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Interactions Sol Plante Atmosphère (UMR ISPA), Ecole Nationale Supérieure des Sciences Agronomiques de Bordeaux-Aquitaine (Bordeaux Sciences Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2024
• Subjects: Canadian boreal forests; Carbon balance; Remote sensing; Forest degradation; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Global warming
• Online Access: https://hal.science/hal-04498572; https://hal.science/hal-04498572/document; https://hal.science/hal-04498572/file/1-s2.0-S1569843224000839-main.pdf; https://doi.org/10.1016/j.jag.2024.103729

International audience The carbon sinks of North American boreal forests have been threatened by global warming and forest disturbances in recent decades, but knowledge about the carbon balance of these forests in recent years remains unknown. We tracked annual aboveground carbon (AGC) changes from 2016 to 2021 across the forest regions of NASA’s Arctic Boreal Vulnerability Experiment (ABoVE) core study domain, using Vegetation Optical Depth derived from low-frequency passive microwave observations. The results showed that these forests showed a net AGC increase of + 28.49 Tg C/yr during the study period, with total AGC gains of + 219.34 Tg C/yr counteracting total AGC losses of −190.86 Tg C/yr. Forest degradation (-162.21 Tg C/yr), defined as a reduction in the capacity of forest to provide goods and services, contributes 5 times more to the total AGC loss than forest cover loss (-28.65 Tg C/yr), defined as the complete removal of tree cover. This indicates that degradation has dominated AGC loss in the region.