Beyond No-till: Tillage Intensity Variations and Resulting Impacts On Soil C Sequestration.

While the scientific community generally agrees that no-till will result in soil C storage, the practice faces production challenges or other issues in certain regions/climates. In wetter regions, crop yields are sometimes lower and N₂O emissions may be higher; weed problems have emerged in other places. With these considerations, the feasibility of using tillage reduction, rather than cessation, may warrant further examination from both a practical and a net greenhouse gas perspective. Although there are suggestions of potential, significant variability in baseline conditions and inconsistent definitions for conservation tillage have led to low certainty regarding the ability of these activities to store soil C or otherwise reduce GHG emissions.

Using a meta-analysis of over 500 field observations from the scientific literature that record soil C change with clearly-defined tillage intensities, we help answer these questions and explore which conservation tillage practices could be incentivized in carbon markets or in public policy. This assessment also includes factors such as climate, crop type, sampling depth, and time. By doing so, we can prioritize regions or cropping systems to achieve the best environmental outcome.