Do Mitigation Strategies Reduce Global Warming Potential in the Northern U.S. Corn Belt?
- Jane M.-F. Johnson *a,
- David W. Archerb,
- Sharon L. Weyersa and
- Nancy W. Barboura
- a USDA–ARS, North Central Soil Conservation Research Laboratory, 803 Iowa Ave., Morris, MN 56267
b USDA–ARS, Northern Great Plains Research Laboratory, 1701 10th Ave. SW, Mandan, ND 58554. Assigned to Associate Editor Pierre-Andre Jacinthe. The use of trade, firm, or corporation names in this publication is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the United States Department of Agriculture or the Agricultural Research Service of any product or service to the exclusion of others that may be suitable. The USDA is an equal opportunity provider and employer. This is a contribution to the USDA–ARS–GRACEnet project
Agricultural management practices that enhance C sequestration, reduce greenhouse gas emission (nitrous oxide [N2O], methane [CH4], and carbon dioxide [CO2]), and promote productivity are needed to mitigate global warming without sacrificing food production. The objectives of the study were to compare productivity, greenhouse gas emission, and change in soil C over time and to assess whether global warming potential and global warming potential per unit biomass produced were reduced through combined mitigation strategies when implemented in the northern U.S. Corn Belt. The systems compared were (i) business as usual (BAU); (ii) maximum C sequestration (MAXC); and (iii) optimum greenhouse gas benefit (OGGB). Biomass production, greenhouse gas flux, change in total and organic soil C, and global warming potential were compared among the three systems. Soil organic C accumulated only in the surface 0 to 5 cm. Three-year average emission of N2O and CH4 was similar among all management systems. When integrated from planting to planting, N2O emission was similar for MAXC and OGGB systems, although only MAXC was fertilized. Overall, the three systems had similar global warming potential based on 4-yr changes in soil organic C, but average rotation biomass was less in the OGGB systems. Global warming potential per dry crop yield was the least for the MAXC system and the most for OGGB system. This suggests management practices designed to reduce global warming potential can be achieved without a loss of productivity. For example, MAXC systems over time may provide sufficient soil C sequestration to offset associated greenhouse gas emission.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © 2011. . Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.