Recent leveling off of vegetation greenness and primary production reveals the increasing soil water limitations on the greening Earth

• 作者: Xiaoming Feng Bojie Fu Yuan Zhang Naiqing Pan Zhenzhong Zeng Hanqin Tian Yihe Lyu Yongzhe Chen Philippe Ciais Yingping Wang Lu Zhang Lei Cheng Fernando T.Maestre Marcos Fernández-Martínez Jordi Sardans Josep Pe?uelas
• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2021,（14）
• 所属期刊栏目: ARTICLES
• 页码范围: 1462-1471
• 页数: 10页
• 语种: 英文

摘要

Global vegetation photosynthesis and productivity have increased substantially since the 1980s,but this trend is heterogeneous in both time and space.Here,we categorize the secular trend in global vegetation greenness into sustained greening,sustained browning and greening-to-browning.We found that by 2016,increased global vegetation greenness had begun to level off,with the area of browning increasing in the last decade,reaching 39.0 million km2(35.9％of the world's vegetated area).This area is larger than the area with sustained increasing growth(27.8 million km2,26.4％);thus,12.0％±3.1％(0.019±0.004 NDV1 a-1)of the previous earlier increase has been offset since 2010(2010-2016,P＜0.05).Global gross primary production also leveled off,following the trend in vegetation greenness in time and space.This leveling off was caused by increasing soil water limitations due to the spatial expansion of drought,whose impact dominated over the impacts of temperature and solar radiation.This response of global gross primary production to soil water limitation was not identified by land submodels within Earth sys-tem models.Our results provide empirical evidence that global vegetation greenness and primary pro-duction are offset by water stress and suggest that as global warming continues,land submodels may overestimate the world's capacity to take up carbon with global vegetation greening.