A greening Earth has reversed the trend of decreasing carbonate weathering under a warming climate
摘要
The response of mineral weathering and its related Weathering Sink for atmospheric CO2 (WSatm-CO2) to global vegetation greening are not well understood. After applying different biogeochemical models and a field experiment to investigate the influence of vegetation greening and warming on the variations of carbonate weathering and WSatm-CO2 on regional and global scales, here we show a significant positive relationship between global carbonate weathering intensity ([HCO3−] as a proxy) and vegetation greenness. During 1982–2018, under a warming climate, [HCO3−] and WSatm-CO2 increase by 5.8% and 6.1%, respectively, due to vegetation greening, in the carbonate areas of Southwest China. Meanwhile, the [HCO3−] in global carbonate areas increases by +2.4% during the same period. By contrast, the [HCO3−] in global carbonate areas decreases by −1.3% without a vegetation function due to the warming. Moreover, we estimated that the carbonate weathering enhancements due to vegetation restoration at the global scale could reach 43.8%. Our results demonstrate that future vegetation restoration is important for the carbon capture by mineral weathering.