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Abstract: Background: The large-scale ecological burdens of beef production are coupled with increasing global demand for beef. As the top producer and a leading global consumer of beef, the U.S. should lead the development of innovative strategies to reduce the pollution and resource use of this system. While much attention has been devoted to increasing production efficiency or reducing consumpt... read moreion, analyses of transformative approaches that view structural change as requisite for sustainability have been limited. Increasing reliance on local or regional foods is such an approach, and consumer demand for these foods is high. Accordingly, the objective of this research is to explore whether regional beef production systems provide opportunities to enhance sustainability and the food supply in the Northeastern United States. Methods: This project used a mixed-methods approach that included life cycle assessment and geospatial analysis with primary and secondary data. Objective 1 was an attributional, environmental life cycle assessment (LCA) of regional grass-fed and dairy beef production systems. Life cycle inventories were initially developed with secondary data and expert opinion, and then further calibrated with producer interviews (n=12). Objective 2 used geospatial analysis to enhance a method that estimates the land use efficiency of livestock systems from a human food supply perspective, the land use ratio (LUR). Land use data was collected during farm interviews (Objective 1) and combined with spatial data on land cover and potential crop productivity for grass-fed and dairy beef case studies. Objective 3 used consequential life cycle assessment to assess whether substituting food waste for corn in regional dairy beef cattle rations could reduce environmental burdens and the LUR. The induced effects of shifting the application of food waste from anaerobic digestion to feed were included in the system boundary. Results: Per kg beef produced, Northeast dairy beef had lower global warming potential, eutrophication potential, acidification potential, and agricultural land use than grass-fed with higher fossil depletion and similar water depletion. However, per ha agricultural land, eutrophication and acidification of grass-fed were lower than dairy beef. Both grass-fed and dairy beef had LUR greater than one, indicating that converting suitable feed land to food crops could produce more human digestible protein. The LUR of grass-fed beef was 3-6 times larger (less efficient) than dairy beef. Finally, substituting food waste for corn in dairy beef cattle rations, instead of using it as a feedstock for anaerobic digestion, reduced global warming potential, acidification potential, and feed-food competition as measured by the LUR. Implications: Innovations in dairy, beef, and waste management systems can be strategies to move toward sustainability in the region. A pilot program to develop regional waste-fed dairy beef should be prioritized. Furthermore, states and municipalities should develop policies and support structures that encourage waste-to-feed. Finally, although accounting for ecosystem services provided by pasture-based farming systems was not possible in this project, they should not be ignored. Standardized methods are needed to account for ecosystem services in LCA for more holistic assessments of environmental and social sustainability in the future.
Thesis (Ph.D.)--Tufts University, 2016.
Submitted to the Dept. of Agriculture, Food and Environment.
Advisor: Timothy Griffin.
Committee: Christian Peters, and Gregory Norris.
Keywords: Agriculture, and Environmental science.read less
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