Corn-Based Ethanol Production and Environmental Quality: A Case of Iowa and the Conservation Reserve Program

Abstract

Growing demand for corn due to the expansion of ethanol has increased concerns that environmentally sensitive lands retired from agricultural production and enrolled into the Conservation Reserve Program (CRP) will be cropped again. Iowa produces more ethanol than any other state in the United States, and it also produces the most corn. Thus, an examination of the impacts of higher crop prices on CRP land in Iowa can give insight into what we might expect nationally in the years ahead if crop prices remain high. We construct CRP land supply curves for various corn prices and then estimate the environmental impacts of cropping CRP land through the Environmental Policy Integrated Climate (EPIC) model. EPIC provides edge-of-field estimates of soil erosion, nutrient loss, and carbon sequestration. We find that incremental impacts increase dramatically as higher corn prices bring into production more and more environmentally fragile land. Maintaining current levels of environmental quality will require substantially higher spending levels. Even allowing for the cost savings that would accrue as CRP land leaves the program, a change in targeting strategies will likely be required to ensure that the most sensitive land does not leave the program.

The Water Footprint of Biofuels: A Drink or Drive Issue?

“…One proposal to avert removal of land from the CRP program is to increase CRP payments, which totaled more than $1.6 billion 2007 (31). However, some analysts suggest that even doubling the payments would not be sufficient to retain land in the CRP (9).…”

“…In 2007, Secchi and Babcock estimated that over 526,000 ha of Iowa farmland would likely be pulled from the CRP and put into a corn/soybeans rotation if corn prices hit $196/t ($5/bu) (9) (43)). Although CRP contracts are established on a 10-15 yr basis, enrollment in the program is already decreasing.…”

“…Numerous recent studies have considered the latter, with a primary focus on air quality (4)(5)(6), land use (7)(8)(9), and net energy value (10)(11)(12)(13)(14)(15). These studies generally reflect beneficial environmental trade-offs for biofuels compared to fossil fuels, with a few notable exceptions that recently considered greater CO 2 emissions associated with massive deforestation in tropical regions (8,10,16).…”

Is bioenergy for the birds? An evaluation of alternative future bioenergy landscapes

“…The consequences of biofuels policy for conservation are largely unintended but are nonetheless predictable. For example, increased demand for row crops can lead to commodity price increases that are likely to result in reductions in the amount of land enrolled in conservation programs (5,13). A variety of financial and logistical factors currently limit the shift from firstto second-generation biofuels.…”

The Impact of Agricultural Land Use Change on Lake Water Quality: Evidence from Iowa

“…The former are able to model complex relationships between the climate, land use, and water quality to examine issues that might otherwise be intractable. For example, simulations from these types of programs have been used to examine the hypoxia "dead zone" in the Gulf of Mexico (Rabotyagov, 2014), the effect of corn-based ethanol on environmental quality (Secchi, 2009), and the potential for cropland to reduce flood risk (Schilling, 2014). Simulation models are invaluable for gaining insight into issues that may otherwise be too complicated for any one statistical model to capture, but they have drawbacks.…”