Long‐term warming increased carbon sequestration capacity in a humid subtropical forest

作者：Xujun Liu, Zhiyang Lie, Peter B. Reich, Guoyi Zhou, Junhua Yan, Wenjuan Huang, Ying‐Ping Wang, Josep Peñuelas, David T. Tissue, Mengdi Zhao, Ting Wu, Donghai Wu, Wenfang Xu, Yuelin Li, Xuli Tang, Shu‐Yi‐Dan Zhou, Ze Meng, Shizhong Liu, Guowei Chu, Deqiang Zhang, Qianmei Zhang, Xinhua He, Juxiu Liu · 发表于：Global Change Biology · 年份：2023 · DOI：10.1111/gcb.17072 · 被引用次数：38 · 研究领域：Plant Water Relations and Carbon Dynamics、Forest ecology and management、Fire effects on ecosystems

Tropical and subtropical forests play a crucial role in global carbon (C) pools, and their responses to warming can significantly impact C-climate feedback and predictions of future global warming. Despite earth system models projecting reductions in land C storage with warming, the magnitude of this response varies greatly between models, particularly in tropical and subtropical regions. Here, we conducted a field ecosystem-level warming experiment in a subtropical forest in southern China, by translocating mesocosms (ecosystem composed of soils and plants) across 600 m elevation gradients with temperature gradients of 2.1°C (moderate warming), to explore the response of ecosystem C dynamics of the subtropical forest to continuous 6-year warming. Compared with the control, the ecosystem C stock decreased by 3.8% under the first year of 2.1°C warming; but increased by 13.4% by the sixth year of 2.1°C warming. The increased ecosystem C stock by the sixth year of warming was mainly attributed to a combination of sustained increased plant C stock due to the maintenance of a high plant growth rate and unchanged soil C stock. The unchanged soil C stock was driven by compensating and offsetting thermal adaptation of soil microorganisms (unresponsive soil respiration and enzyme activity, and more stable microbial community), increased plant C input, and inhibitory C loss (decreased C leaching and inhibited temperature sensitivity of soil respiration) from soil drying. These results ...