|Rotz, Clarence - Al
Submitted to: American Forage and Grassland Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 12/15/2017
Publication Date: 1/22/2017
Citation: Rotz, C.A., Asem-Hiablie, S. 2017. The role of forage systems in environmentally sustainable beef. American Forage and Grassland Conference Proceedings. American Forage and Grassland Council, Berea, KY. Pg.1.
Interpretive Summary: No Interpretive Summary is required. JLB.
Technical Abstract: To develop better scientific understanding of the sustainability of beef in the United States, a national assessment is being conducted with support from the Beef Checkoff. This includes a life cycle assessment (LCA) of important environmental, social and economic impact categories of the beef value chain. Forage systems play a major role in the environmental impacts of cattle production. Results thus far show farm-gate carbon footprints of representative production systems vary from 16 to 28 kg of carbon dioxide equivalent (CO2e)/kg of carcass weight (CW) with a mean around 20 kg CO2e/kg CW. The cow-calf operation is the source of 67 to 77% of this footprint and stocker operations contribute up to 18%. Thus, depending upon whether cattle are backgrounded on pasture or in a feedlot, the grassland-based portion of the system contributes 67 to 85% of the farm-gate carbon footprint of finished beef cattle. Considering post farm-gate sources (harvest, retail, restaurant and consumer) the full carbon footprint is about 45 kg CO2e/kg of consumed beef. Of this total, 58 to 73% can be attributed to emissions from cattle on grassland and the inputs required to maintain them. A similar result is found for environmental impacts such as fossil energy use and total reactive nitrogen loss where 50 to 70% of these farm-gate footprints are attributed to grazing cattle. In the full LCA, grazing animals are also the major contributor to acidification potential and abiotic resource depletion. To make substantial reductions in the environmental impacts of beef, mitigation strategies are needed to reduce greenhouse gas and nitrogen emissions from forage grazing systems. This provides a major challenge for beef cattle research because practical technologies or strategies for reducing these emissions are essentially unknown.