The Carbon Sequestration Potential of Regenerative Farming Practices in South Carolina, USA

Abstract

Current production agriculture systems typically focus on yield outcomes at all costs. By shifting to best management practices based on regenerative farming principles, however, agricultural systems worldwide could maintain or even improve yields while sequestering atmospheric carbon (C) into soil organic matter (SOM). To demonstrate the effectiveness of regenerative principles at simultaneously benefiting agriculture and reducing greenhouse gasses, their C sequestration potential was examined through SOM data from 486 soil sampling locations from multiple farms throughout the coastal plains of South Carolina. These data were compared over varying multiple-year periods between 2013 and 2017 as their land management practices shifted from conventional methods to those based on the regenerative-based practice of cover cropping. The implementation of cover crops in crop rotations resulted in statistically significant mean SOM percentage increases of 0.11 (p ≤ 0.001), 0.11 (p ≤ 0.001), and 0.55 (p ≤ 0.001) for sampling sites converted into rotations utilizing cover crops for two, three, and four years, respectively. When averaged out per year for each sampling group, this results in an average of 622, 425, and 1584 lbs./acre/year of C fixed from the atmosphere and retained in the soil as organic matter. Increases were observed across all soil types sampled in the study with soil texture not significantly influencing a soils' ability to increase soil OM or sequester atmospheric C through cover crop implementation. The calculations based on the coastal plains' soils studied here demonstrate the promising potential of the application of regenerative farming principles to not only restore degraded biodiversity, recycle nutrients, improve farm profitability, and reduce chemical inputs, but also to sequester atmospheric C and simultaneously help reduce the effect of global climate change while creating healthy soils.

Impact of coal mining on land use changes, deforestation, biomass, and C losses in Central India: Implications for offsetting CO2 emissions

“…Numerous studies had widely recognized that agricultural lands act as both sinks and sources of C and hence play a key role in regional C budgets (Lamb et al, 2021; Paustian et al, 2016; Poeplau & Don, 2015). Regenerative agriculture practices such as crop rotations, use of cover crops, green manures, tillage changes, amending soil with straw and manures, halting the process of burning crop residues, biochar applications, growing of perennial crops, grasses, and so forth improve the C stocks on crop lands and mitigating climate change simultaneously boosting crop yield, soil health, and increasing efficiencies of nutrients and water use (Kenne & Kloot, 2019; Lal, 2004; Paustian et al, 2016; Smith et al, 2008). Literature estimated the wide range of sequestration rates and was estimated from 0.32 to 1.5 Mg C ha −1 yr −1 for cover crops (Poeplau & Don, 2015), compost addition to rangelands was 0.5 to 3.3 Mg C ha −1 yr −1 (Ogle et al, 2005; Ryals et al, 2015) and no‐tillage practices was ~0.25 and 0.29 Mg C ha −1 yr −1 on sandy and non‐sandy soils, respectively.…”

Regenerative Agriculture—A Literature Review on the Practices and Mechanisms Used to Improve Soil Health

“…The literature on the climate mitigation potential of fully regenerative farming is scarce. In South Carolina, US, investigations revealed a significant increase in SOC at multiple farms that switched from conventional fallowing to regenerative cover cropping practices with limited chemical and N application [439]. Similarly, recent modelling indicates that adopting RA practices could reduce GHG emissions by 14-27% in arable lands in the UK within 30 years [440].…”

The soil microbiome: An essential, but neglected, component of regenerative agroecosystems

“… 5 Perhaps most importantly, RA is purported to increase atmospheric carbon sequestration and is, therefore, touted as a strategy to help address global climate change issues. 10 While the RA “movement” is being increasingly adopted by farmers at the grassroots level, comprehensive scientific research on the ecosystem-level changes induced by RA, relative to conventional farming systems, has only recently gained momentum; thus, questions remain about the extent to which regenerative approaches are able to achieve better environmental outcomes, such as soil quality improvements and climate change mitigation, compared to conventional practices.…”