Skip to main content
ARS Home » Northeast Area » University Park, Pennsylvania » Pasture Systems & Watershed Management Research » Research » Publications at this Location » Publication #358862
Research Project: Multifunctional Farms and Landscapes to Enhance Ecosystem Services (Bridge Project)

Location: Pasture Systems & Watershed Management Research

Title: Spatially and temporally explicit life cycle analysis of global warming, eutrophication and acidification from corn production in the U.S. Midwest

Author
item KYUNG LEE, EUN - State University Of New York (SUNY)
item XUESONG, ZHANG - Pacific Northwest National Laboratory
item Adler, Paul
item KLEPPEL, GARY - State University Of New York (SUNY)
item XIAOBO, XUE - State University Of New York (SUNY)

Submitted to: Journal of Cleaner Production
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/16/2019
Publication Date: 1/1/2020
Citation: Kyung Lee, E., Xuesong, Z., Adler, P.R., Kleppel, G.S., Xiaobo, X. 2020. Spatially and temporally explicit life cycle analysis of global warming, eutrophication and acidification from corn production in the U.S. Midwest. Journal of Cleaner Production. 242:1-11. https://doi.org/10.1016/j.jclepro.2019.118465.
DOI: https://doi.org/10.1016/j.jclepro.2019.118465

Interpretive Summary: Although we know that crop production practices vary greatly over regions, nationally averaged data are often used for crop environmental impact assessments. In this study, we quantified the variation in environmental impacts of corn production over years across the major corn production region in the United States. We found that environmental impacts varied greatly over the corn production region in the United States due to differences in soils and weather and across years generally due to effects of weather on corn production and environmental loses. This study demonstrates the large variation in environmental impacts of corn production in the United States and suggests there may be strategies for reducing this impact.

Technical Abstract: The demand for biobased products, such as food, fuel, and chemicals, has been continuously increasing. Meanwhile, agricultural production, serving as the primary stage of biobased products, is one of the largest contributors to greenhouse gas (GHG) emissions and nutrient releases. Environmental impacts of agricultural production influenced by farming practices, soil properties, and climate conditions, are often site-specific and time dependent. Although assessing spatially and temporally explicit environmental releases and impacts are required to inform a sustainable trajectory for agricultural production, such analyses are largely lacking. This study provides site-specific analysis of on-farm and supply chain emissions from corn production to demonstrate the spatio-temporal variability of environmental impacts in the Midwest U.S. states. Using process-based life cycle assessment (LCA) and the physically-based Environmental Policy Integrated Climate (EPIC) agroecosystem model, we estimated county-level life cycle environmental release inventories from corn production in 12 Midwest U.S. states for the period of 2000-2008. Based on the Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI) impact assessment model, we quantified the corresponding life cycle global warming (GW), eutrophication (EU) and acidification (AD) impacts of corn. Overall, we found that life cycle GW, EU and AD of corn production varied by a factor of 4.2, 83.7 and 10.6, respectively, across the Midwest counties over the nine-year span (2000-2008). Life cycle GW impacts of producing 1 kg of corn ranged from -6.4 in Franklin County, Illinois to 20.2 kg CO2-eq. in Perkins County, South Dakota. The life cycle EU impacts also spanned over a wide range of 0.99 g in Morton County, Kansas to 82.9 g N-eq. in Leelanau County, Michigan, whereas life cycle AD impacts range from 1.3 in Clermont County, Ohio to 100.7 g SO2-eq. in Perkins County, South Dakota. Moreover, tradeoffs existed among life cycle GW, EU and AD impact categories for corn production. The spatial variation analysis showed that key contributors were the different soil types, precipitation, elevation and the amounts of fertilizers applied. These findings provided critical insight into spatio-temporal variations of life cycle environmental impacts of corn production, and identified spatial hotspots and top contributors for improving environmental performances of corn production.