Greenhouse Gas Mitigation Potential of Corn Ethanol: Accounting for Corn Acreage Expansion

  • Lyubov A. Kurkalova
  • Silvia Secchi
  • Phillip W. Gassman
Conference paper


Combustion of corn-based ethanol substantially offsets net Greenhouse Gas (GHG) emissions by the recycling of carbon dioxide (CO2) stored as biomass. However, the GHG mitigation effect may be partially countered by the growth of CO2 emissions from the increased corn production resulting from the increased demand for corn and higher corn prices. This study assesses the effect for a major U.S. crop production region, the Boone River watershed in Iowa. We use economic models on GIS-based land use and soils data for some 8,275 fields in the watershed to estimate the effect of an increase in corn prices on crop rotations and tillage intensity. The associated changes in soil carbon are estimated using the field-scale Environmental Policy Impact Climate simulation model by comparing soil organic carbon content under the baseline with that under the simulated cropping patterns. A corn price increase from $2 to $4 per bushel ($78.74 to $157.47 per t) is predicted to lead to the switch from the corn-soybean rotation to continuous corn and from the mulch to conventional tillage on the most of the watershed. The associated CO2 emissions are estimated at 63,711 tons (57,799 t) per year higher than under the baseline.


Soil Organic Carbon Conventional Tillage Farm Operation Corn Ethanol Continuous Corn 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



Part of this research has been supported by the USDA. The findings do not reflect the views of the USDA or its staff. The authors would like to thank Todd Campbell for computational assistance and Chad Hart for valuable discussions.


  1. Duffy, M., and D. Smith. 2007. “Estimated Costs of Crop Production in Iowa – 2007.” File A1-20, Iowa State University Extension, Ames, Iowa. URL:
  2. FAPRI Staff, 2007. “FAPRI 2007 U.S. and World Agricultural Outlook." FAPRI Publications 07-fsr1, Food and Agricultural Policy Research Institute (FAPRI) at Iowa State University. URL:
  3. Iowa Cooperative Soil Survey. 2003. Iowa Soil Properties and Interpretation Database. URL:
  4. Izzauralde, R.C., J.R. Williams, W.B. McGill, N.J. Rosenberg, and M.C. Quiroga Jakas. 2006. “Simulating Soil C Dynamics with EPIC: Model Description and Testing against Long-Term Data.” Ecological Modeling 192:362–384.CrossRefGoogle Scholar
  5. Katsvairo, T., and W.J. Cox. 2000. Economics of Cropping Systems Featuring Different Rotations, Tillage, and Management.” Agronomy Journal 92 (3):485–493.CrossRefGoogle Scholar
  6. Lal, R. 2004. “Carbon Emissions from Farm Operations.” Environment International. 30:981–990.CrossRefGoogle Scholar
  7. McCarl, B.A., D. Gillig, H.-C. Lee, M. El-Halwagi, X. Qin, and G.C. Cornforth. 2005. “Potential for biofuel-based Greenhouse Gas emission Mitigation: Rationale and Potential.” In J. Outlaw, K.J. Collins, and J.A. Duffield (Eds.), Agriculture as a Producer and Consumer of Energy, pp. 300–316.Google Scholar
  8. McNew, K., and D. Griffith. 2005. “Measuring the impact of ethanol plants on local grain prices.” Review of Agricultural Economics. 27(2):164–180.CrossRefGoogle Scholar
  9. Secchi, S., and B.A. Babcock. 2007. “Impact of High Corn Prices on Environmental Quality: A Case of Iowa and the Conservation Reserve Program.” CARD Working Paper 07-WP 447. Center for Agricultural and Rural Development, Iowa State University. May. URL:
  10. Sibbing, J. 2007. “Setting America on the Right Biofuels Path.” Journal of Soil and Water Conservation. 62(3):48A.Google Scholar
  11. Soil Survey Staff, Natural Resources Conservation Service, U.S. department of Agriculture. 2006. Soil Survey Geographic (SSURGO) Database for Iowa. URL:
  12. Werblow, S. 2007. “More Corn: Is Conservation Tillage at Risk?” Partners: Quarterly Publication of the Conservation Technology Information Center. April, 25(2).Google Scholar
  13. West, T.O., and G. Marland. 2002. “A Synthesis of Carbon Sequestration, Carbon Emissions, and Net Carbon Flux in Agriculture: Comparing Tillage Practices in the United States.” Agriculture, Ecosystems and Environment. 91:217–232.CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Lyubov A. Kurkalova
    • 1
  • Silvia Secchi
    • 2
  • Phillip W. Gassman
    • 2
  1. 1.North Carolina A&T State UniversityGreensboroUSA
  2. 2.Iowa State UniversityAmesUSA

Personalised recommendations