Carbon turnover times shape topsoil carbon difference between Tibetan Plateau and Arctic tundra

• Published in: Science Bulletin
• Main Authors: Wu, Donghai, Liu, Dan, Wang, Tao, Ding, Jinzhi, He, Yujie, Ciais, Philippe, Zhang, Gengxin, Piao, Shilong
• Other Authors: Sino-French Institute for Earth System Science, College of Urban and Environmental Sciences, Peking University Beijing, Chinese Academy of Sciences Beijing (CAS), Key Laboratory of Alpine Ecology and Biodiversity, Institute of Tibetan Plateau Research - Chinese Academy of Sciences, CAS Center for Excellence in Tibetan Plateau Earth Sciences, Department of Earth System Science Irvine (ESS), University of California Irvine (UC Irvine), University of California (UC)-University of California (UC), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), ICOS-ATC (ICOS-ATC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), This work was supported by Preliminary Research on Three Poles Environment and Climate Change (2019YFC1509103), the National Natural Science Foundation of China (41861134036 and 41922004), the Second Tibetan Plateau Scientific Expedition and Research Program (2019QZKK0606), and the Strategic Priority Research Program (A) of the Chinese Academy of Sciences (XDA19070303 and XDA20050101).
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: Tibetan Plateau; Arctic tundra; Soil organic carbon; Net primary production; Carbon turnover time; Radiocarbon; [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Arctic; permafrost; Tundra
• Online Access: https://hal.science/hal-03233487; https://doi.org/10.1016/j.scib.2021.04.019

International audience The Tibetan Plateau (TP) and Arctic permafrost constitute two large reservoirs of organic carbon, but processes which control carbon accumulation within the surface soil layer of these areas would differ due to the interplay of climate, soil and vegetation type. Here, we synthesized currently available soil carbon data to show that mean organic carbon density in the topsoil (0–10 cm) in TP grassland (3.12 ± 0.52 kg C m$^{−2}$) is less than half of that in Arctic tundra (6.70 ± 1.94 kg C m$^{−2}$). Such difference is primarily attributed to their difference in radiocarbon-inferred soil carbon turnover times (547 years for TP grassland versus 1609 years for Arctic tundra) rather than to their marginal difference in topsoil carbon inputs. Our findings highlight the importance of improving regional-specific soil carbon turnover and its controlling mechanisms across permafrost affected zones in ecosystem models to fully represent carbon-climate feedback.