Assessing Soil Organic C Sequestration with the Soil Conditioning Index in the Southeastern USA.

Soil organic C sequestration can be a significant driver of how conservation management systems are adopted by producers and promoted by government agencies.  Simulation of various tillage, crop rotation, and cover cropping conditions across the cotton growing region of the southeastern USA would allow us to assess whether soil type, climatic conditions, or management has the greatest control on soil organic C sequestration potential in the region.  We used the recently calibrated soil conditioning index (SCI) to estimate potential soil organic C sequestration under conventional and conservation management of cotton cropping systems in counties throughout the Cotton Belt.  Management scenarios included (1) conventional tillage continuous cotton, (2) no tillage continuous cotton with winter cover crop, (3) no tillage cotton-cotton-peanut-corn rotation with winter cover crop, (4) no tillage cotton-corn-wheat/soybean rotation with winter cover crop, and (5) no tillage cotton-cotton-clover/grass hay-grass pasture-corn rotation with winter cover crop.  The results of this study will be valuable to producers, extension agents, scientists, and policy makers in evaluating how the SCI performs under a diversity of environmental and management conditions throughout the southeastern USA.