Presentation from the AAAS annual meeting, San Franciso, 2007
View presentation here: (Powerpoint, 11000 kb)
Kenneth G. Cassman Director, Nebraska Center for Energy Science Research, University of Nebraska.
Abstract: The sustainability of U.S. agriculture must be considered from a global perspective because U.S. agriculture accounts for the greatest share of world food exports. Agriculture must address the following global challenges: continued population increase, limited arable land and water resources, climate change, and rising prices for petroleum-based motor fuels. Of these, rising fuel prices are having the largest impact on agriculture because they are driving a rapid expansion of biofuel production from grain, sugar, and oilseed crops—both in the U.S. and globally. The benefits from biofuels are compelling: decreased reliance on imported petroleum, a reduction in greenhouse gas emissions, increased agricultural commodity prices and farm income, rural jobs and economic development, and reduced crop subsidies. High commodity prices will motivate farmers to increase crop yields and expand production area. A marked acceleration in the rate of yield gain for the major crops will be required to avoid conversion of marginal land not suited for crop production, and conservation of centers of biodiversity such as grassland savannahs, forests and wetlands. Crop and soil management practices used to achieve substantially higher yields must protect water and soil quality and contribute to a reduction in greenhouse gas emissions. Although it is possible to meet these challenges, the magnitude of scientific innovation required has been underestimated. A dynamic, real-time, site-specific, “ecological systems approach” will be needed. Biotechnology and transgenic crops are not a silver bullet. Eventually, development of cellulosic (biomass) ethanol will reduce the need to use food crops for biofuels, but large-scale deployment of cellulosic ethanol systems is 7-10 years away. During this period, grain-sugar-oilseed biofuel systems will build out to utilize a significant portion of global food crop production. There is an urgent need to focus research and technology development on ensuring the environmental sustainability of high-yield food-crop systems to meet demand for both food and biofuels.