Soil management practices of major crops in the United States and their potential for carbon sequestration

Although the United States has no areas considered strictly tropical, there are subtropical and warm humid regions in the south where agricultural production is high. Practices in these regions, and the results of research on their effects towards carbon sequestration in soils, are certainly transferable to tropical regions. Soil management (e.g., tillage and amendment) and crop management (e.g., cropping system and cover crops) practices in the United States (with emphasis on the southern region) as well as new technologies and advances are covered in this chapter. Regulatory pathways for increasing carbon stores in managed agricultural lands in the United States are unlikely; therefore, willingness on the part of farmers to adopt practices aligned with C sequestration goals must be engendered. Reduced tillage and cover crop inclusion are being adopted more commonly in the United States. Reuse of organic waste materials for the benefit of agricultural production is also increasing. Breeding for greater or more stable root mass, and new methods for monitoring the flux of C from the soil to the atmosphere both represent exciting frontiers of discovery in this area.