Soil carbon sequestration in global working lands as a gateway for negative emission technologies

Authors: ALMARAZ, MAYA - University Of California, Davis; SIMMONDS, MAEGEN - Pivot Bio; BOUDINOT, GARRETT - Cornell University; DI VITTORIO, ALAN - Lawrence Berkeley National Laboratory; BINGHAM, NINA - University Of California, Davis; KHALSA, SAT DARSHAN - University Of California, Davis; Ostoja, Steven; SCOW, KATE - University Of California, Davis; JONES, ANDREW - University Of California, Davis; HOLZER, IRIS - University Of California, Davis; MANAIGO, ERIN - University Of California, Davis; GEOGHEGAN, EMILY - University Of California, Davis; GOERTZEN, HEATH - University Of California, Davis; SILVER, WHENDEE - University Of California, Davis

Submitted to: Global Change Biology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/12/2023
Publication Date: 7/21/2023
Citation: Almaraz, M., Simmonds, M., Boudinot, G., Di Vittorio, A.V., Bingham, N., Khalsa, S., Ostoja, S.M., Scow, K., Jones, A., Holzer, I., Manaigo, E., Geoghegan, E., Goertzen, H., Silver, W. 2023. Promotion of soil carbon in working lands as a gateway for negative emission technologies. Global Change Biology. 00:1-11. https://doi.org/10.1111/gcb.16884.
DOI: https://doi.org/10.1111/gcb.16884

Interpretive Summary: The impacts of climate change are already being felt on a global scale and are expected to amplify significantly in the years and decades to come. Soil carbon sequestration (SCS) practices in working lands including croplands and rangelands provides a cost-effective means for removing carbon (C) from the atmosphere while also delivering co-benefits to people and ecosystems. We estimated if SCS were deployed to between on one quarter to half of globally available working lands globally, our modeling efforts suggested that that combined SCS practices such as agroforestry or cover cropping can provide 40-80% of the required C sequestration by the Paris Climate Agreement. Soil carbon sequestration provides a pathway to climate stabilization that can be implemented immediately, eliciting atmospheric C draw down in the near term that can last decades to centuries.

Technical Abstract: The ongoing climate crisis merits an urgent need to devise management approaches and new technologies to reduce atmospheric greenhouse gas concentrations (GHG) in the near term. However, each year that GHG concentrations continue to rise, pressure mounts to develop and deploy atmospheric CO2 removal pathways as a complement to, and not replacement for, emissions reductions. Soil carbon sequestration (SCS) practices in working lands provide a low-tech and cost-effective means for removing CO2 from the atmosphere while also delivering co-benefits to people and ecosystems. Our model estimates suggest that, assuming additive effects, the technical potential of combined SCS practices can provide 30%–70% of the carbon removal required by the Paris Climate Agreement if applied to 25%–50% of the available global land area, respectively. Atmospheric CO2 drawdown via SCS has the potential to last decades to centuries, although more research is needed to determine the long-term viability at scale and the durability of the carbon stored. Regardless of these research needs, we argue that SCS can at least serve as a bridging technology, reducing atmospheric CO2 in the short term while energy and transportation systems adapt to a low-C economy. Soil C sequestration in working lands holds promise as a climate change mitigation tool, but the current rate of implementation remains too slow to make significant progress toward global emissions goals by 2050. Outreach and education, methodology development for C offset registries, improved access to materials and supplies, and improved research networks are needed to accelerate the rate of SCS practice implementation. Herein, we present an argument for the immediate adoption of SCS practices in working lands and recommendations for improved implementation.