Maximizing Photosynthesis and Root Exudates through Regenerative Agriculture to Increase Soil Organic Carbon to Mitigate Climate Change

Volume 8, Issue 1, February 2023     |     PP. 1-26      |     PDF (289 K)    |     Pub. Date: February 3, 2023
DOI: 10.54647/agriculture210317    113 Downloads     90921 Views  

Author(s)

Andre Frederick Leu, International Director, Regeneration International

Abstract
To shift from a significant emitter to a major mitigator of greenhouse gas (GHG) emissions, agriculture needs to change from the current dominant paradigm of chemically intensive, industrial/conventional systems to regenerative systems by focusing on plant biology and living soil sciences. Maximizing photosynthesis to capture and convert atmospheric CO2 into organic molecules to store as soil organic carbon (SOC) would be an effective carbon dioxide removal (CDR) technology to mitigate climate change.
The world reached 420 parts per million (ppm) of CO2 in the atmosphere in May 2022. The Global Carbon Budget report estimated that atmospheric CO2 reached an annual average of 417.2 ppm in 2022.
Evidence shows that 430 ppm carbon dioxide equivalents (CO2eq) to limit warming to 1.5°C and 450 ppm CO2eq to limit warming to 2°C have been exceeded. Reducing emissions and transitioning to renewable energy is no longer sufficient to stop temperatures from exceeding 2oC, the higher limit of the Paris Agreement. Negative emissions are needed to remove the legacy levels of CO2. The Intergovernmental Panel on Climate Change (IPCC) stated that without additional sequestration, global mean surface temperature will increase in 2100 between 3.7°C and 4.8°C higher than pre-industrial levels. The IPPC states that CDR is essential in limiting global warming to 1.5°C to achieve net negative emissions. It advocated for CDR technologies such as regenerating natural ecosystems, carbon capture and storage (CCS), and soil carbon sequestration (SCS).
Regenerative agriculture is based on a range of food and farming systems that maximize the photosynthesis of plants to capture CO2 and use organic matter biomass and root exudates to store it as SOC. It can be applied to all agricultural sectors, including cropping, grazing, and perennial horticulture. Meta-reviews and other published studies have found that transitioning to regenerative agriculture systems can result in more sequestration than emissions from agriculture, turning agriculture from a significant emitter to a major mitigator of GHG emissions.
Scaling up 10% of various best practice regenerative agriculture systems is realistic, achievable, and low-cost. Just a percentage of innovators and early adopters applying best practice regenerative systems to their land holdings can significantly contribute to achieving the negative emissions needed to limit global warming to 1.5°C higher than pre-industrial levels.

Keywords
regenerative agriculture, soil organic carbon, climate change, carbon capture and storage, soil carbon sequestration, root exudates, plant biology, soil microbiome

Cite this paper
Andre Frederick Leu, Maximizing Photosynthesis and Root Exudates through Regenerative Agriculture to Increase Soil Organic Carbon to Mitigate Climate Change , SCIREA Journal of Agriculture. Volume 8, Issue 1, February 2023 | PP. 1-26. 10.54647/agriculture210317

References

[ 1 ] "4 per 1000” Initiative, 2022, https://4p1000.org/?lang=en Accessed August 31, 2022
[ 2 ] Aguilera E, Lassaletta L, Gattinger A and Gimeno BS, 2013. Managing soil carbon for climate change mitigation and adaptation in Mediterranean cropping systems: A meta-analysis. Agriculture Ecosystems and Environment 168:25-36.
[ 3 ] Andrés, P.; Doblas-Miranda, E.; Silva-Sánchez, A.; Mattana, S.; Font, F. Physical, Chemical, and Biological Indicators of Soil Quality in Mediterranean Vineyards under Contrasting Farming Schemes. Agronomy 2022, 12, 2643. https://doi.org/10.3390/ agronomy12112643
[ 4 ] Amundson R and Biardeau L 2018 Opinion: Soil carbon sequestration is an elusive climate mitigation tool, Proceedings of the National Academy of Sciences, USA 115:11652–11656.
[ 5 ] Badri DV, Vivanco JM 2009, "Regulation and function of root exudates". Plant, Cell & Environment. 32 (6): 666–81. doi:10.1111/j.1365-3040.2009.01926.x
[ 6 ] BBC 2022, https://www.bbc.com/news/business-61741352 (accessed Oct 2, 2022)
[ 7 ] Christopher S. F, Lal R and Mishra, U, 2009. Long-term no-till effects on carbon sequestration in the Midwestern U.S. Soil Science Society of America Journal, 73: 207-216.
[ 8 ] Chomel M, Lavallee J M, Alvarez-Segura N, Baggs E M, Caruso T, de Castro F, Emmerson MC, Magilton M, de Vries F T, Johnson D & Bardgett R D 2022, Intensive grassland management disrupts below-ground multi-trophic resource transfer in response to drought, Nature Communications, November 2022
[ 9 ] Emissions Reduction Fund, Case Studies 2022, Australian Government Clean Energy Regulator, Soil Carbon https://www.cleanenergyregulator.gov.au/Infohub/case-studies/emissions-reduction-fund-case-studies#Soil-carbon Accessed Sept 4, 2022
[ 10 ] FAO 2010, Global Livestock Environmental Assessment Model (GLEAM), https://www.fao.org/gleam/results/en/ Accessed September 1, 2022
[ 11 ] FAOSTAT 2015, United Nation’s Food and Agriculture Organization, FAOSTAT data on land use, retrieved December 4, 2015
[ 12 ] Friedlingstein, P., O'Sullivan, M., Jones, M. W., Andrew, R. M., Gregor, L., Hauck, J., Le Quéré, C., Luijkx, I. T., Olsen, A., Peters, G. P., Peters, W., Pongratz, J., Schwingshackl, C., Sitch, S., Canadell, J. G., Ciais, P., Jackson, R. B., Alin, S. R., Alkama, R., Arneth, A., Arora, V. K., Bates, N. R., Becker, M., Bellouin, N., Bittig, H. C., Bopp, L., Chevallier, F., Chini, L. P., Cronin, M., Evans, W., Falk, S., Feely, R. A., Gasser, T., Gehlen, M., Gkritzalis, T., Gloege, L., Grassi, G., Gruber, N., Gürses, Ö., Harris, I., Hefner, M., Houghton, R. A., Hurtt, G. C., Iida, Y., Ilyina, T., Jain, A. K., Jersild, A., Kadono, K., Kato, E., Kennedy, D., Klein Goldewijk, K., Knauer, J., Korsbakken, J. I., Landschützer, P., Lefèvre, N., Lindsay, K., Liu, J., Liu, Z., Marland, G., Mayot, N., McGrath, M. J., Metzl, N., Monacci, N. M., Munro, D. R., Nakaoka, S.-I., Niwa, Y., O'Brien, K., Ono, T., Palmer, P. I., Pan, N., Pierrot, D., Pocock, K., Poulter, B., Resplandy, L., Robertson, E., Rödenbeck, C., Rodriguez, C., Rosan, T. M., Schwinger, J., Séférian, R., Shutler, J. D., Skjelvan, I., Steinhoff, T., Sun, Q., Sutton, A. J., Sweeney, C., Takao, S., Tanhua, T., Tans, P. P., Tian, X., Tian, H., Tilbrook, B., Tsujino, H., Tubiello, F., van der Werf, G. R., Walker, A. P., Wanninkhof, R., Whitehead, C., Willstrand Wranne, A., Wright, R., Yuan, W., Yue, C., Yue, X., Zaehle, S., Zeng, J., and Zheng, B.: Global Carbon Budget 2022, Earth Syst. Sci. Data, 14, 4811–4900, https://doi.org/10.5194/essd-14-4811-2022, 2022.
[ 13 ] Gattinger A, Muller A, Haeni M, Skinner C, Fliessbach A, Buchmann N, Mäder P, Stolze M, Smith P, El-Hage Scialabba N and Niggli U, 2012. Enhanced top soil carbon stocks under organic farming. Proceedings of the National Academy of Sciences 109:18226-18231.
[ 14 ] IPCC, 2014: Summary for Policymakers. In: Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Edenhofer, O., R. Pichs-Madruga, Y. Sokona, E. Farahani, S. Kadner, K. Seyboth, A. Adler, I. Baum, S. Brunner, P. Eickemeier, B. Kriemann, J. Savolainen, S. Schlömer, C. von Stechow, T. Zwickel and J.C. Minx (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.
[ 15 ] IPCC, 2018: Summary for Policymakers. In: Global Warming of 1.5°C. An IPCC Special Report on the impacts of global warming of 1.5°C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty [Masson-Delmotte, V., P. Zhai, H.-O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. Waterfield (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 3-24. https://doi.org/10.1017/9781009157940.001.
[ 16 ] IPCC 2022, Climate Change 2022 Mitigation of Climate Change, Working Group III Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change, Summary for Policymakers, Eds Priyadarshi R. Shukla et al. ISBN 978-92-9169-160-9 https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6_WGIII_SPM.pdf accessed Aug27,2022
[ 17 ] Johnson D, Ellington J and Eaton W, 2015, Development of soil microbial communities for promoting sustainability in agriculture and a global carbon fix, PeerJ PrePrints | http://dx.doi.org/10.7287/peerj.preprints.789v1 | CC-BY 4.0 Open Access | rec: 13 Jan 2015, publ: 13 Jan 2015
[ 18 ] Jones DL, Nguyen C, Findlay RD 2009, "Carbon flow in the rhizosphere: carbon trading at the soil–root interface". Plant and Soil. 321 (1–2): 5–39. doi:10.1007/s11104-009-9925-0
[ 19 ] Khan, S.A., R.L. Mulvaney, T.R. Ellsworth, and C.W. Boast. 2007. The myth of nitrogen fertilization for soil carbon sequestration. Journal of Environmental Quality 36:1821-1832. \
[ 20 ] Kulp SA & Strauss BH 2019, New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding, Nature Communications, (2019)10:4844, https://doi.org/10.1038/s41467-019-12808-z, www.nature.com/naturecommunications
[ 21 ] Lal R 2004 Soil Carbon Sequestration Impacts on Global Climate Change and Food Security, Environmental Science, 11 June 2004
[ 22 ] Lal R, Follett RF, Stewart BA and Kimble JM 2007, Soil Carbon Sequestration to Mitigate Climate Change and Advance Food Security. Soil Science, 172, 943-956.
[ 23 ] Lam SK, Chen D, Mosier AR and Roush R 2013, The potential for carbon sequestration in Australian agricultural soils is technically and economically limited. Sci. Rep. 3, 2179; (2013).
[ 24 ] Leu A 2013, Commentary V: Mitigating climate change with soil organic matter in organic production systems. TRADE AND ENVIRONMENT REVIEW, 2013, WAKE UP BEFORE IT IS TOO LATE, Ed. Ulrich Hoffman, UNCTAD/DITC/TED/2012/3 UNITED NATIONS PUBLICATION ISSN 1810-5432
[ 25 ] Leu A 2014, THE POTENTIAL FOR MITIGATION AND ADAPTATION TO CLIMATE CHANGE WITH SOIL ORGANIC MATTER INCREASES IN ORGANIC PRODUCTION SYSTEMS . Acta Horticulturae. 1018, 75-82
[ 26 ] Leu A 2021a, Our Global Regeneration Revolution: Organic 3.0 to Regenerative and Organic Agriculture https://regenerationinternational.org/2021/07/12/our-global-regeneration-revolution-organic-3-0-to-regenerative-and-organic-agriculture/
[ 27 ] Leu A 2021b, GROWING LIFE, REGENERATING FARMING AND RANCHING, Acres USA, Greeley Colorado, USA, December 2021
[ 28 ] Machmuller MB, Kramer MG, Cyle TK, Hill N, Hancock D & Thompson A, 2015. Emerging land use practices rapidly increase soil organic matter, Nature Communications 6, Article number: 6995 doi:10.1038/ncomms7995, Received 21 June 2014 Accepted 20 March 2015 Published 30 April 2015
[ 29 ] Mulvaney, R.L., S.A., Khan, and T.R. Ellsworth. 2009. Synthetic nitrogen fertilizers deplete soil nitrogen: A global dilemma for sustainable cereal production. Journal of Environmental Quality 38:2295-2314.
[ 30 ] Man, M., B. Deen, K.E. Dunfield, C.Wagner-Riddle, and M.J. Simpson. 2021.Altered soil organic matter composition and degradation after a decade of nitrogen fertilization in a temperate agroecosystem. Agriculture, Ecosystems & Environment 310:107305.
[ 31 ] NASA 2019, The Atmosphere: Getting a Handle on Carbon Dioxide, https://climate.nasa.gov/news/2915/the-atmosphere-getting-a-handle-on-carbon-dioxide, Accessed Aug 28, 2022
[ 32 ] NOAA 2017, National Oceanic and Atmospheric Administration (US) https://www.climate.gov/news-features/climate-qa/how-much-will-earth-warm-if-carbon-dioxide-doubles-pre-industrial-levels, Accessed Aug 28, 2022
[ 33 ] NOAA 2021, Climate Change: Atmospheric Carbon Dioxide, https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide, Accessed Aug 28, 2022
[ 34 ] NOAA 2020, Climate Change: Ocean Heat Content, https://www.climate.gov/news-features/understanding-climate/climate-change-ocean-heat-content, Accessed Aug 28, 2022
[ 35 ] NOAA 2022, Carbon dioxide now more than 50% higher than pre-industrial levels, https://www.noaa.gov/news-release/carbon-dioxide-now-more-than-50-higher-than-pre-industrial-levels?fbclid=IwAR3_PAk4AmI4czOO5ikK_CAGca94LMwQwIEfG9lo3ZWi72BeR6KaX05hHSw, Accessed Aug 27, 2022
[ 36 ] Ogle SM, Swan A and Paustian K. 2012, No-till management impacts on crop productivity, carbon input and soil carbon sequestration, Agriculture, Ecosystems &Environment, Volume 149, 1 March 2012, Pages 37-49 https://doi.org/10.1016/j.agee.2011.12.010
[ 37 ] Olson K R 2013, Soil organic carbon sequestration, storage, retention and loss in U.S. croplands: Issues paper for protocol development. Geoderma, 2013; 195-196: 201 DOI: 10.1016/j.geoderma.2012.12.004
[ 38 ] Prescott C E, Rui Y, Cotrufo M F, and Grayston SAJ 2021, Managing plant surplus carbon to generate soil organic matter in regenerative agriculture, Journal of Soil and Water Conservation, Nov/Dec 2021, Vol.76, No 6.
[ 39 ] Robertson B and Mousavian M 2022, The Carbon Capture Crux - Lessons Learned, The Institute for Energy Economics and Financial Analysis (IEEFA) https://ieefa.org/resources/carbon-capture-remains-risky-investment-achieving-decarbonisation, Accessed Sept 4, 2022
[ 40 ] Rodale 2022, Farming Systems Trial 40-YEAR REPORT, Rodale Institute, https://rodaleinstitute.org/science/farming-systems-trial, Accessed December 8, 2022
[ 41 ] Rogers, Everett M. (1962). Diffusion of innovations (1st ed.). New York: Free Press of Glencoe.
[ 42 ] Rohling EJ, K. Grant, M. Bolshaw, A. P. Roberts, M. Siddall, Ch. Hemleben and M. Kucera (2009) Antarctic temperature and global sea level closely coupled over the past five glacial cycles, Nature Geoscience, advance online publication, www.nature.com/naturegeoscience
[ 43 ] Soil Kee 2019, World first at the Soilkee farm, with first carbon credits issued to a soil carbon project under the Emissions Reduction Fund and the Paris Agreement, https://soilkee.com.au/gallery/20190314-soilkee%20media%20release%20.pdf Accessed Sept 4, 2022
[ 44 ] Statista, 2022 https://www.statista.com/statistics/1091926/atmospheric-concentration-of-co2-historic/ Accessed Aug 27
[ 45 ] Teague, W.R., S.L. Dowhower, S.A. Baker, N. Haile, P.B. DeLaune, and D.M. Conover. 2011. Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie. Agriculture Ecosystems and Environment 141:310-22.
[ 46 ] Teague W R, Apfelbaum S, Lal R, Kreuter U P, Rowntree J, Davies C A, Conser R, Rasmussen M, Hatfield J, Wang T, Wang F and Byck P, 2016,The role of ruminants in reducing agriculture’s carbon footprint in North America, Journal of Soil and Water Conservation March 2016, 71 (2) 156-164; DOI: https://doi.org/10.2489/jswc.71.2.156
[ 47 ] Teague, W.R., F. Provenza, U.P. Kreuter, T. Steffens, and M. Barnes. 2013. Multi-paddock grazing on rangelands: Why the perceptual dichotomy between research results and rancher experience? Journal of Environmental Management 128:699-717.
[ 48 ] Teasdale JR, Coffman CB and Mangum RW (2007). Potential long-term benefits of no-tillage and organic cropping systems for grain production and soil improvement. Agronomy Journal, Sept–Oct, 99 (5): 1297-1305.
[ 49 ] Tong W, Teague W R, Park C S and Bevers S, 2015, GHG Mitigation Potential of Different Grazing Strategies in the United States Southern Great Plains, Sustainability 2015, 7, 13500-13521; doi:10.3390/su71013500, ISSN 2071-1050, www.mdpi.com/journal/sustainability The role of ruminants in reducing agriculture's carbon footprint in North America
[ 50 ] UNFCCC 2022, The Paris Agreement, https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement, Accessed Aug 28
[ 51 ] van Groenigen JW, van Kessel C, Hungate BA, Oenema O, Powlson DS and van Groenigen KJ 2017, Sequestering Soil Organic Carbon: A Nitrogen Dilemma, Environmental Science and Technology. 2017
[ 52 ] Vargas Zeppetello LR, Adrian E, Raftery AE and Battisti DS 2022, Probabilistic projections of increased heat stress driven by climate change, Communications Earth & Environment, (2022)3:183 | https://doi.org/10.1038/s43247-022-00524-4 www.nature.com/commsenv
[ 53 ] Verma S and Verma A 2021, Plant Root Exudate Analysis, in PHYTOMICROBIOME INTERACTIONS AND SUSTAINABLE AGRICULTURE, Editor(s):Verma A, Saini JK, Hesham A and Singh HB, John Wiley & Sons Ltd 2021, Print ISBN:9781119644620, Online ISBN:9781119644798
[ 54 ] Winona 2022, What is Pasture Cropping, https://winona.net.au/pasture-cropping/, Accessed September 4, 2022
[ 55 ] White RE 2022, The Role of Soil Carbon Sequestration as a Climate Change Mitigation Strategy: An Australian Case Study. Soil Systems. 2022, 6,46.