Quantifying direct yield benefits of soil carbon increases from cover cropping

Journal Article · Mon May 29 00:00:00 EDT 2023 · Nature Sustainability

DOI:https://doi.org/10.1038/s41893-023-01131-7· OSTI ID:2325294

Vendig, Isaac ^[1]; Guzman, Aidee ^[1]; De La Cerda, Gisel ^[1]; Esquivel, Kenzo ^[1]; Mayer, Allegra C. ^[2]; Ponisio, Lauren ^[3]; Bowles, Timothy M. ^[1]

---

1. University of California, Berkeley, CA (United States)
2. Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
3. University of Oregon, Eugene, OR (United States)

Cropland management practices that restore soil organic carbon (SOC) are increasingly presented as climate solutions that also enhance yields. But how often these benefits align at the farm level—the scale of farmers’ decision making—remains uncertain. Here we examined concurrent SOC and yield responses to cover cropping, including their direct connection, with a global meta-analysis. Cover cropping simultaneously increased yields and SOC in 59.7% of 434 paired observations. Increases in SOC directly increased crop yields in soils with initial SOC concentrations below 11.6 g kg-1; for example, a change from 5 g kg^-1 to 6 g kg^-1 increased yields by +2.4%. These yield benefits of SOC did not decline as nitrogen inputs increased or when legume cover crops were used, suggesting fertility inputs cannot substitute for SOC effects. Regardless of direct effects of SOC increases on yields, integrating legume cover crops into systems with simplified rotations or with nitrogen inputs < 157 kg ha^-1 season^-1 N led to the largest yield increases (up to +24.3%), with legumes also increasing SOC more than non-legumes (up to +1.5 g kg^-1). By simultaneously increasing yields and SOC, cover cropping provides an opportunity to benefit both food security and climate, including via direct yield benefits from SOC increases on low carbon soils.

• Research Organization: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)
• Sponsoring Organization: US Department of Agriculture (USDA); USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: AC52-07NA27344
• OSTI ID: 2325294
• Report Number(s): LLNL--JRNL-842822; 1065205
• Journal Information: Nature Sustainability, Journal Name: Nature Sustainability Journal Issue: 9 Vol. 6; ISSN 2398-9629
• Publisher: Springer Nature
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
58 GEOSCIENCES
cover crops
crop yields
meta-analysis
soil organic carbon