Li Xiaojun, Ciais Philippe, Fensholt Rasmus, Chave Jérome, Sitch Stephen, Canadell Josep G, Brandt Martin, Fan Lei, Xiao Xiangming, Tao Shengli, Wang Huan, Albergel Clément, Yang Hui, Frappart Frédéric, Wang Mengjia, Bastos Ana, Maisongrande Philippe, Qin Yuanwei, Xing Zanpin, Cui Tianxiang, Yu Ling, He Lei, Zheng Yi, Liu Xiangzhuo, Liu Yuqing, De Truchis Aurelien, Wigneron Jean-Pierre
INRAE, Bordeaux Sciences Agro, UMR 1391 ISPA, Villenave-d'Ornon, France.
Faculty of Geosciences and Engineering, Southwest Jiaotong University, Chengdu, 611756, China.
Nat Commun. 2025 Jun 2;16(1):4980. doi: 10.1038/s41467-025-59999-2.
Northern ecosystems (≥ 30° N) have been accumulating vegetation biomass carbon in recent decades, but increasing droughts and wildfires threaten this carbon sink. Here, we analyse annual changes in live vegetation biomass in northern ecosystems using low-frequency microwave satellite observations at 25 km spatial resolution from 2010 to 2022. We find that live biomass carbon stocks have undergone a reversal from a positive to a negative trend during the study period with 2016 marking the turning point. During 2016-2022, live biomass carbon stocks decreased at a rate of PgC yr across northern ecosystems, primarily in temperate biomes ( PgC yr). The annual mean gross loss of 4% of live biomass carbon in this region during 2016-2022 reflects high interannual variability, with significant losses associated with droughts and a further drop of PgC in the very dry year of 2022. Our findings highlight the vulnerability of live biomass carbon stocks to emerging climate-induced disturbances in northern ecosystems, challenging the sustainability of the current large terrestrial carbon sink in this key region for the global carbon balance.
近几十年来，北半球生态系统（北纬≥30°）一直在积累植被生物量碳，但日益频繁的干旱和野火威胁着这一碳汇。在此，我们利用2010年至2022年空间分辨率为25千米的低频微波卫星观测数据，分析了北半球生态系统中活植被生物量的年度变化。我们发现，在研究期间，活生物量碳储量经历了从正向负的趋势转变，2016年为转折点。在2016年至2022年期间，北半球生态系统的活生物量碳储量以每年PgC的速率下降，主要发生在温带生物群落（每年PgC）。2016年至2022年期间，该地区活生物量碳年平均总损失率为4%，反映出年际变化较大，干旱导致了显著损失，在2022年极度干旱年份，活生物量碳储量进一步下降了PgC。我们的研究结果突出了北半球生态系统中活生物量碳储量对新出现的气候诱发干扰的脆弱性，对这一全球碳平衡关键区域目前巨大陆地碳汇的可持续性构成了挑战。
