Skip to main content
ARS Home » Midwest Area » Morris, Minnesota » Soil Management Research » Research » Publications at this Location » Publication #332452
Title: Environmental impact assessment of double- and relay-cropping with winter camelina in the northern Great Plains, USA

Author
item BERTI, MARISOL - North Dakota State University
item JOHNSON, BURTON - North Dakota State University
item RIPPLINGER, DAVID - North Dakota State University
item Gesch, Russell - Russ
item APONTE, ALFREDO - North Dakota State University

Submitted to: Agricultural Systems
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/22/2017
Publication Date: 5/29/2017
Publication URL: https://handle.nal.usda.gov/10113/5700700
Citation: Berti, M., Johnson, B., Ripplinger, D., Gesch, R.W., Aponte, A. 2017. Environmental impact assessment of double- and relay-cropping with winter camelina in the northern Great Plains, USA. Agricultural Systems. 156:1-12.

Interpretive Summary: Double cropping methods, whereby winter camelina is grown as the first crop, followed by a food or forage crop (e.g., soybean and sorghum) increases agricultural productivity by producing two crops in a single season. It can also potentially improve the energy balance of the system, provide certain environmental benefits through adding biodiversity, and help balance food and energy production. In this study, three different computer models were used to estimate the potential environmental impact of double cropping with winter camelina as compared to monocropped (i.e., one crop per season) corn and soybean in the upper Midwest. The data used for modeling were taken from a previous study that evaluated the agronomics of 10 different crop sequences of winter camelina double cropped with soybean, sorghum, and corn as compared with each specie grown as a monocrop. Results showed that the global warming potential (GWP) of winter camelina production, caused by greenhouse gas emissions (e.g., carbon dioxide and nitrous oxide), was at a modest level, lower than that for corn production. However, when a second crop was added following camelina, GWP increased, but in total, it still was not higher than a single-season corn crop. The increased GWP of double cropping with camelina was mainly due to the additional agricultural management needed to produce both crops in a single season. Winter camelina production itself was found to have lower environmental impact than either monocropped corn or soybean. Moreover, double cropping increased biodiversity and forage resources for pollinators, and increased wildlife habitat. Results of this study will be of interest and use for scientists and the bioenergy industry seeking to gain a better understanding of the potential impacts of intensified agricultural practices such as double cropping have on the environment.

Technical Abstract: Recent findings indicate that double- or relay-cropping winter camelina (Camelina sativa L. Crantz.) with feed or food crops can increase yield per area, improve energy balance, and provide several ecosystem services. Double-cropping can help balance food and energy production. The objective of this study was to determine the environmental impact of double and relay-crop systems as compared with monocultured maize (Zea mays L.) and soybean (Glycine max (L.) Merr.) in the Midwest. Ten crop sequences composed of double- and relay-cropped forage sorghum [Sorghum bicolor (L.) Moench.], soybean, and maize with winter camelina were evaluated and compared with their monoculture counterparts. The environmental aspects evaluated included global warming potential (GWP), abiotic depletion, acidification, eutrophication, ecotoxicity, and human toxicity. Additionally, provisioning and regulating ecosystem services were evaluated, including: primary aboveground productivity, soil erosion, and biodiversity in each crop sequence. The analysis was conducted from ‘cradle-to-gate’, including only the agricultural phase. Global warming potential estimated by three different methods indicated that winter camelina had a GWP of 579 to 922 kg CO2e ha-1. Adding a second crop after winter camelina increased GWP by 235 to 540 kg CO2e ha-1. Maize in monoculture had higher GWP than all other double and relay cropping systems studied. The higher emissions of double- and relay-cropping systems and maize can be explained by higher N fertilizer application, which led to greater estimated field N2O emissions. Also, the additional sowing and harvesting of the double or relay crop increased CO2 emissions due to increased diesel use. Winter camelina had the lowest values in all impact categories, indicating camelina agricultural production phase has low environmental impact compared with maize and soybean in monoculture. Double- and relay- cropping systems increased biodiversity, provided more sources for pollinators, and habitat for wildlife. The realized environmental benefits of these systems may encourage more farmers to adopt sustainable agricultural practices.