Terrestrial photosynthesis inferred from plant carbonyl sulfide uptake

• 成果类型: Article
• 署名作者: Lai, Jiameng; Kooijmans, Linda M. J.; Sun, Wu; Lombardozzi, Danica; Campbell, J. Elliott; Gu, Lianhong; Luo, Yiqi; Kuai, Le; Sun, Ying
• 署名单位: Cornell University; Wageningen University & Research; Carnegie Institution for Science; Colorado State University System; Colorado State University Fort Collins; University of California System; University of California Santa Cruz; United States Department of Energy (DOE); Oak Ridge National Laboratory; National Aeronautics & Space Administration (NASA); NASA Jet Propulsion Laboratory (JPL); California Institute of Technology
• 刊物名称: Nature
• ISSN/ISSBN: 0028-6227
• DOI: 10.1038/s41586-024-08050-3
• 发表日期: 2024-10-01
• 页码: 855-+
• 关键词: mesophyll diffusion conductance; gas-exchange; fluxes; co2; MODEL; seasonality; anhydrase; boreal; forest

摘要

Terrestrial photosynthesis, or gross primary production (GPP), is the largest carbon flux in the biosphere, but its global magnitude and spatiotemporal dynamics remain uncertain(1). The global annual mean GPP is historically thought to be around 120PgCyr(-1) (refs.(2-6)), which is about 30-50PgCyr(-1) lower than GPP inferred from the oxygen-18 (O-18) isotope(7) and soil respiration(8). This disparity is a source of uncertainty in predicting climate-carbon cycle feedbacks(9,10). Here we infer GPP from carbonyl sulfide, an innovative tracer for CO2 diffusion from ambient air to leaf chloroplasts through stomata and mesophyll layers. We demonstrate that explicitly representing mesophyll diffusion is important for accurately quantifying the spatiotemporal dynamics of carbonyl sulfide uptake by plants. From the estimate of carbonyl sulfide uptake by plants, we infer a global contemporary GPP of 157(8.5)PgCyr(-1), which is consistent with estimates from O-18 (150-175PgCyr(-1)) and soil respiration (149(-23)(+29)PgCyr(-1)), but with an improved confidence level. Our global GPP is higher than satellite optical observation-driven estimates (120-140PgCyr(-1)) that are used for Earth system model benchmarking. This difference predominantly occurs in the pan-tropical rainforests and is corroborated by ground measurements(11), suggesting a more productive tropics than satellite-based GPP products indicated. As GPP is a primary determinant of terrestrial carbon sinks and may shape climate trajectories(9,10), our findings lay a physiological foundation on which the understanding and prediction of carbon-climate feedbacks can be advanced.