ARS | Publication request: Impact of second-generation biofuel agriculture on greenhouse gas emissions in the corn-growing regions of the US

Submitted to: Frontiers in Ecology and the Environment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 24, 2011
Publication Date: March 1, 2012
Repository URL: http://10: 69–74, doi:10.1890/110003
Citation: Davis, S., Parton, W., Del Grosso, S.J., Keough, C., Marx, E., Adler, P.R., Delucia, E. 2011. Impact of second-generation biofuel agriculture on greenhouse gas emissions in the corn-growing regions of the US. Frontiers in Ecology and the Environment. 10:69-74.

Interpretive Summary: Land use for bioenergy crops is controversial because terrestrial resources that supply food, livestock feed, and ecosystem services already compete for geographical space in some regions of the world. Currently, in the US, both animal feed and bioenergy are produced from the food crop corn, despite the water and air pollution that are associated with the mass production of this plant. We estimated the effects of replacing corn ethanol cropping with alternative crops on both food and ecosystem services. If perennial feedstocks were planted on cropland that is currently used for corn ethanol production in the Mississippi watershed, we could achieve 82% more ethanol, 4% more grain for food, 16% reduction in nitrogen leaching, and a 452% reduction in greenhouse gas emissions without requiring any more agricultural land.

Technical Abstract: Land use for bioenergy crops is controversial because terrestrial resources that supply food, livestock feed, and ecosystem services already compete for geographical space in some regions of the world. Currently, in the US, both feed and bioenergy are produced from the food crop Zea mays L. (corn), despite the water and air pollution that are associated with the mass production of this species. We estimated the effects of replacing corn ethanol feedstocks with alternative crops on both food and ecosystem services. If cellulosic feedstocks were planted on cropland that is currently used for ethanol production in the Mississippi watershed, we could achieve 82% more ethanol, 4% more grain for food, 16% reduction in nitrogen leaching, and a 452% reduction in greenhouse gas emissions without incurring any indirect land use change.