Warming-induced vapor pressure deficit suppression of vegetation growth diminished in northern peatlands

• Published in: Nature communications Vol. 14; no. 1; p. 7885
• Main Authors: Chen, Ning, Zhang, Yifei, Yuan, Fenghui, Song, Changchun, Xu, Mingjie, Wang, Qingwei, Hao, Guangyou, Bao, Tao, Zuo, Yunjiang, Liu, Jianzhao, Zhang, Tao, Song, Yanyu, Sun, Li, Guo, Yuedong, Zhang, Hao, Ma, Guobao, Du, Yu, Xu, Xiaofeng, Wang, Xianwei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 30.11.2023; Nature Publishing Group; Nature Portfolio
• Subjects: 704/106/694; 704/172; 704/172/4081; Field tests; Humanities and Social Sciences; multidisciplinary; Peatlands; Plant growth; Regional analysis; Regional planning; Relative humidity; Science; Science (multidisciplinary); Stomata; Surface properties; Vapor pressure; Vapors; Vegetation; Vegetation growth; Water pressure; Water use
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-023-42932-w

Recent studies have reported worldwide vegetation suppression in response to increasing atmospheric vapor pressure deficit (VPD). Here, we integrate multisource datasets to show that increasing VPD caused by warming alone does not suppress vegetation growth in northern peatlands. A site-level manipulation experiment and a multiple-site synthesis find a neutral impact of rising VPD on vegetation growth; regional analysis manifests a strong declining gradient of VPD suppression impacts from sparsely distributed peatland to densely distributed peatland. The major mechanism adopted by plants in response to rising VPD is the “open” water-use strategy, where stomatal regulation is relaxed to maximize carbon uptake. These unique surface characteristics evolve in the wet soil‒air environment in the northern peatlands. The neutral VPD impacts observed in northern peatlands contrast with the vegetation suppression reported in global nonpeatland areas under rising VPD caused by concurrent warming and decreasing relative humidity, suggesting model improvement for representing VPD impacts in northern peatlands remains necessary. Growing vapor pressure deficit inhibits vegetation growth. Here, Chen et al. combine satellite and eddy covariance data with field experiments showing that plant growth in northern peatlands is not constrained by water even in the presence of a warming-induced water pressure deficit.