Integrating the evidence for a terrestrial carbon sink caused by increasing atmospheric CO2

Anthony P Walker; Martin G De Kauwe; Ana Bastos; Soumaya Belmecheri; Katerina Georgiou; Ralph F Keeling; Sean M McMahon; Belinda E Medlyn; David J P Moore; Richard J Norby; Sönke Zaehle; Kristina J Anderson-Teixeira; Giovanna Battipaglia; Roel J W Brienen; Kristine G Cabugao; Maxime Cailleret; Elliott Campbell; Josep G Canadell; Philippe Ciais; Matthew E Craig; David S Ellsworth; Graham D Farquhar; Simone Fatichi; Joshua B Fisher; David C Frank; Heather Graven; Lianhong Gu; Vanessa Haverd; Kelly Heilman; Martin Heimann; Bruce A Hungate; Colleen M Iversen; Fortunat Joos; Mingkai Jiang; Trevor F Keenan; Jürgen Knauer; Christian Körner; Victor O Leshyk; Sebastian Leuzinger; Yao Liu; Natasha MacBean; Yadvinder Malhi; Tim R McVicar; Josep Penuelas; Julia Pongratz; A Shafer Powell; Terhi Riutta; Manon E B Sabot; Juergen Schleucher; Stephen Sitch; William K Smith; Benjamin Sulman; Benton Taylor; César Terrer; Margaret S Torn; Kathleen K Treseder; Anna T Trugman; Susan E Trumbore; Phillip J van Mantgem; Steve L Voelker; Mary E Whelan; Pieter A Zuidema

doi:10.1111/nph.16866

Integrating the evidence for a terrestrial carbon sink caused by increasing atmospheric CO₂

New Phytol. 2021 Mar;229(5):2413-2445. doi: 10.1111/nph.16866. Epub 2020 Oct 21.

Authors

Anthony P Walker¹, Martin G De Kauwe^{2

3

4}, Ana Bastos⁵, Soumaya Belmecheri⁶, Katerina Georgiou⁷, Ralph F Keeling⁸, Sean M McMahon⁹, Belinda E Medlyn¹⁰, David J P Moore¹¹, Richard J Norby¹, Sönke Zaehle¹², Kristina J Anderson-Teixeira^{13

14}, Giovanna Battipaglia¹⁵, Roel J W Brienen¹⁶, Kristine G Cabugao¹, Maxime Cailleret^{17

18}, Elliott Campbell¹⁹, Josep G Canadell²⁰, Philippe Ciais²¹, Matthew E Craig¹, David S Ellsworth¹⁰, Graham D Farquhar²², Simone Fatichi^{23

24}, Joshua B Fisher²⁵, David C Frank⁶, Heather Graven²⁶, Lianhong Gu¹, Vanessa Haverd²⁰, Kelly Heilman⁶, Martin Heimann¹², Bruce A Hungate²⁷, Colleen M Iversen¹, Fortunat Joos²⁸, Mingkai Jiang¹⁰, Trevor F Keenan^{29

30}, Jürgen Knauer²⁰, Christian Körner³¹, Victor O Leshyk²⁷, Sebastian Leuzinger³², Yao Liu¹, Natasha MacBean³³, Yadvinder Malhi³⁴, Tim R McVicar^{35

36}, Josep Penuelas^{37

38}, Julia Pongratz^{5

39}, A Shafer Powell¹, Terhi Riutta³⁴, Manon E B Sabot^{2

3

4}, Juergen Schleucher⁴⁰, Stephen Sitch⁴¹, William K Smith¹¹, Benjamin Sulman¹, Benton Taylor⁹, César Terrer⁴², Margaret S Torn³⁰, Kathleen K Treseder⁴³, Anna T Trugman⁴⁴, Susan E Trumbore¹², Phillip J van Mantgem⁴⁵, Steve L Voelker⁴⁶, Mary E Whelan⁴⁷, Pieter A Zuidema⁴⁸

Affiliations

¹ Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
² ARC Centre of Excellence for Climate Extremes, University of New South Wales, Sydney, NSW, 2052, Australia.
³ Climate Change Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia.
⁴ Evolution and Ecology Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia.
⁵ Ludwig Maximilians University of Munich, Luisenstr. 37, Munich, 80333, Germany.
⁶ Laboratory of Tree Ring Research, University of Arizona, 1215 E Lowell St, Tucson, AZ, 85721, USA.
⁷ Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA.
⁸ Scripps Institution of Oceanography, UC San Diego, La Jolla, CA, 92093, USA.
⁹ Smithsonian Environmental Research Center, Edgewater, MD, 21037, USA.
¹⁰ Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW, 2751, Australia.
¹¹ School of Natural Resources and the Environment, 1064 East Lowell Street, Tucson, AZ, 85721, USA.
¹² Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, Jena, 07745, Germany.
¹³ Conservation Ecology Center, Smithsonian Conservation Biology Institute, MRC 5535, Front Royal, VA, 22630, USA.
¹⁴ Center for Tropical Forest Science-Forest Global Earth Observatory, Smithsonian Tropical Research Institute, Panama City, Panama.
¹⁵ Department of Environmental, Biological and Pharmaceutical Sciences and Technologies, Università della Campania, Caserta, 81100, Italy.
¹⁶ School of Geography, University of Leeds, Leeds, LS6 9JT, UK.
¹⁷ INRAE, UMR RECOVER, Aix-Marseille Université, 3275 route de Cézanne, Aix-en-Provence Cedex 5, 13182, France.
¹⁸ Swiss Federal Institute for Forest Snow and Landscape Research (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland.
¹⁹ Department of Geography, University of California Santa Barbara, Santa Barbara, CA, 93106, USA.
²⁰ CSIRO Oceans and Atmosphere, GPO Box 1700, Canberra, ACT, 2601, Australia.
²¹ Laboratoire des Sciences du Climat et de l'Environnement, LSCE/IPSL, CEA-CNRS-UVSQ, Université Paris-Saclay, Gif-sur-Yvette, F-91191, France.
²² Plant Sciences, Research School of Biology, The Australian National University, Canberra, ACT, 2601, Australia.
²³ Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, Singapore, 117576, Singapore.
²⁴ Institute of Environmental Engineering, ETH Zurich, Stefano-Franscini Platz 5, Zurich, 8093, Switzerland.
²⁵ Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, CA, 91109, USA.
²⁶ Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
²⁷ Center for Ecosystem Science and Society, Northern Arizona University, Flagstaff, AZ, 86011, USA.
²⁸ Climate and Environmental Physics, Physics Institute and Oeschger Centre for Climate Change Research, University of Bern, Sidlerstr. 5, Bern, CH-3012, Switzerland.
²⁹ Department of Environmental Science, Policy and Management, UC Berkeley, Berkeley, CA, 94720, USA.
³⁰ Earth and Environmental Sciences Area, Lawrence Berkeley National Lab., Berkeley, CA, 94720, USA.
³¹ Department of Environmental Sciences, Botany, University of Basel, Basel, 4056, Switzerland.
³² School of Science, Auckland University of Technology, Auckland, 1142, New Zealand.
³³ Department of Geography, Indiana University, Bloomington, IN, 47405, USA.
³⁴ School of Geography and the Environment, University of Oxford, Oxford, OX1 3QY, UK.
³⁵ CSIRO Land and Water, GPO Box 1700, Canberra, ACT, 2601, Australia.
³⁶ Australian Research Council Centre of Excellence for Climate Extremes, 142 Mills Rd, Australian National University, Canberra, ACT, 2601, Australia.
³⁷ CSIC, Global Ecology CREAF-CSIC-UAB, Bellaterra, Barcelona, Catalonia, 08193, Spain.
³⁸ CREAF, Cerdanyola del Vallès, Barcelona, Catalonia, 08193, Spain.
³⁹ Max Planck Institute for Meteorology, Bundesstr. 53, 20146 Hamburg, Germany.
⁴⁰ Department of Medical Biochemistry & Biophysics, Umeå University, Umea, 901 87, Sweden.
⁴¹ College of Life and Environmental Sciences, University of Exeter, Exeter, Laver Building, EX4 4QF, UK.
⁴² Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA, 94550, USA.
⁴³ Department of Ecology and Evolutionary Biology, University of California Irvine, Irvine, CA, 92697, USA.
⁴⁴ Department of Geography, 1832 Ellison Hall, Santa Barbara, CA, 93016, USA.
⁴⁵ U.S. Geological Survey, Western Ecological Research Center, Arcata, CA, 95521, USA.
⁴⁶ Department of Environmental and Forest Biology, State University of New York College of Environmental Science and Forestry, Syracuse, NY, 13210, USA.
⁴⁷ Department of Environmental Sciences, Rutgers University, 14 College Farm Road, New Brunswick, NJ, 08901, USA.
⁴⁸ Forest Ecology and Forest Management group, Wageningen University, PO Box 47, Wageningen, 6700 AA, the Netherlands.

PMID: 32789857
DOI: 10.1111/nph.16866

Abstract

Atmospheric carbon dioxide concentration ([CO₂ ]) is increasing, which increases leaf-scale photosynthesis and intrinsic water-use efficiency. These direct responses have the potential to increase plant growth, vegetation biomass, and soil organic matter; transferring carbon from the atmosphere into terrestrial ecosystems (a carbon sink). A substantial global terrestrial carbon sink would slow the rate of [CO₂ ] increase and thus climate change. However, ecosystem CO₂ responses are complex or confounded by concurrent changes in multiple agents of global change and evidence for a [CO₂ ]-driven terrestrial carbon sink can appear contradictory. Here we synthesize theory and broad, multidisciplinary evidence for the effects of increasing [CO₂ ] (iCO₂ ) on the global terrestrial carbon sink. Evidence suggests a substantial increase in global photosynthesis since pre-industrial times. Established theory, supported by experiments, indicates that iCO₂ is likely responsible for about half of the increase. Global carbon budgeting, atmospheric data, and forest inventories indicate a historical carbon sink, and these apparent iCO₂ responses are high in comparison to experiments and predictions from theory. Plant mortality and soil carbon iCO₂ responses are highly uncertain. In conclusion, a range of evidence supports a positive terrestrial carbon sink in response to iCO₂ , albeit with uncertain magnitude and strong suggestion of a role for additional agents of global change.

Keywords: CO2 fertilization; CO2-fertilization hypothesis; beta factor; carbon dioxide; free-air CO2 enrichment (FACE); global carbon cycle; land-atmosphere feedback; terrestrial ecosystems.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Review

MeSH terms

Atmosphere
Carbon Cycle
Carbon Dioxide
Carbon Sequestration*
Climate Change
Ecosystem*

Substances

Carbon Dioxide