The potential of agricultural soils of the upper St. Joseph river watershed to sequester carbon

This paper assesses the potential to sequester C in soils under different land use systems in the Upper St. Joseph River Watershed by evaluating land use and management options that lead to an increase in soil C concentration above the Current levels. Under the present land use systems, the Current soil organic carbon (SOC) sequestration rate calculated for different, soil/crop management practices, ranges between 37.8 and 56.0 Gg yr(-1) (I Gg = 10(9) g = one thousand metric ton). Losses of SOC are primarily due to plow tillage estimated at 12.8 to 20.2 Gg C. The SOC sequestration potential is estimated at 67.8 to 102.0 Gg C yr(-1) through adoption of improved land use and soil/crop management practices. Conversion from plow till to no-till with continuous or rotational cropping system contributes 52% of the total SOC sequestration potential. Restoration of wetlands, incorporation of pasture/hay into the rotation cycle, and conversion to Conservation Reserve Program (CRP) contribute about 48% of the total sequestration potential. (C) 2004 by The Haworth Press, Inc. All rights reserved.