Human Activities Induced Stronger Silicate Weathering in the Red River Basin: A Growing Carbon Sink During the Late Holocene

Abstract Silicate weathering is essential for the global carbon cycle and is a driver of climate change through the consumption of atmospheric CO 2 . Recent studies have pointed out that silicate weathering in the late Holocene was widely influenced by human activities, but the carbon sink effect of silicate weathering under anthropogenic influence remains unclear. In this study, we present continuous records of clay minerals, major elements, and terrigenous mass accumulation rates of Core 45A in the Western South China Sea to reconstruct the evolutionary history of weathering and erosion in the Red River Basin since 3800 cal yr BP. We investigate the interactions between weathering, climate, and human activities. Our results reveal that the silicate weathering intensity and erosion rate have increased significantly since ∼1500 cal yr BP, which is decoupled from the trend to a cooler and drier climate but coincides well with stronger human activities, suggesting the significance of anthropogenic influence on silicate weathering. We also reconstruct the CO 2 consumption flux induced by silicate weathering to quantitatively evaluate the impact of human activities on the carbon sink capacity of silicate weathering. The calculated CO 2 consumption fluxes contributed by anthropogenic activities on silicate weathering show an approximate 150% increase compared to natural conditions in the Red River. Thus, this study highlights that human‐enhanced silicate weathering has reduced atmospheric CO 2 and played an important role in the global carbon cycle during the late Holocene, which has never occurred in the Earth's geological past.