Warming-induced vegetation growth cancels out soil carbon-climate feedback in the northern Asian permafrost region in the 21st century

• Published in: Environmental Research Letters
• Main Authors: Liu, Jianzhao, Yuan, Fenghui, Zuo, Yunjiang, Zhou, Rui, Zhu, Xinhao, Li, Kexin, Wang, Nannan, Chen, Ning, Guo, Ziyu, Zhang, Lihua, Sun, Ying, Guo, Yuedong, Song, Changchun, Xu, Xiaofeng
• Other Authors: Strategic Priority Research Program of the Chinese Academy of Sciences, National Natural Science Foundation of China, Liaoning Provincial Natural Science Foundation
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: IOP Publishing 2022
• Subjects: permafrost
• Online Access: http://dx.doi.org/10.1088/1748-9326/ac7eda; https://iopscience.iop.org/article/10.1088/1748-9326/ac7eda; https://iopscience.iop.org/article/10.1088/1748-9326/ac7eda/pdf

Abstract Permafrost soils represent an enormous carbon (C) pool that is highly vulnerable to climate warming. We used the model output ensemble of the Coupled Model Intercomparison Project Phase 6 to estimate the C storage in soil, litter, and vegetation in the current extent of northern Asian permafrost during 1900–2100. The contemporary (1995–2014) C storage was estimated to be 368.1 ± 82.5 Pg C for the full column depth of the soil, 13.3 ± 4.6 Pg C in litter, and 22.2 ± 3.2 Pg C in vegetation biomass, while these C storage levels are projected to decline by 3.9 Pg C (1.1%) in soils, increase of 0.03 Pg C (0.2%) in litter, and increase by 21.1 Pg C (95.3%) in vegetation biomass by the end of the 21st century under SSP585. The total C storage was dominated by warming-induced vegetation growth. Partial correlation analysis showed that surface air temperature (TAS), soil liquid water, and soil mineral nitrogen (SMN) dominated the soil and vegetation C pools, while SMN controlled litter C during the historical period. Under future scenarios, TAS and SMN dominated the changes of soil and litter C, while TAS determined the vegetation C increase. The growing soil C loss with warming indicates positive C-climate feedback in soils; this warming-induced acceleration of soil C loss was canceled out by the enhanced vegetation C accumulation, leading to a strong C sink in the 21st century.