A Global Model Tracking Water, Nitrogen, and Land Inputs and Virtual Transfers from Industrialized Meat Production and Trade Marshall Burke & Kirsten Oleson & Ellen McCullough & Joanne Gaskell Received: 18 December 2006 / Accepted: 29 April 2008 # Springer Science + Business Media B.V. 2008 Abstract Rising populations and incomes throughout the world have boosted meat demand by over 75% in the last 20years, intensifying pressures on production systems and the natural resources to which they are linked. As a growing proportion of global meat production is traded, the environmental impacts of production become increas- ingly separated from where the meat is consumed. In this paper, we quantify the use of three important resources associated with industrial livestock production and trade— water, land, and nitrogen—using a country-specific model that combines trade, agronomic, biogeochemical, and hydrological data. Our model focuses on pigs and chickens, as these animals are raised predominantly in intensive systems using concentrated, compound feeds. The results describe the geographical patterns of environmental re- source use due to meat production, trade, and consumption. We show that US feed, animal, and meat destined for export require almost as much nitrogen and land, and 20% more water, than products destined for domestic consump- tion. Model results also demonstrate that among various production factors, improvements in crop yields and animal feed conversion efficiencies result in the most significant reductions in environmental harm. By explicitly tracking the externalities of meat production, we hope to bolster suppliers’ accountability and provide better information to meat consumers. Keywords Industrial livestock production . Virtual transfers . Feed use . Water use . Nitrogen transport . Land use . Trade and environment . Environmental impact of meat 1 Introduction The nature of global meat production is changing, with potentially serious consequences for the environment. An urbanizing population coupled with explosive growth in global demand for meat products has changed animal production fundamentally, from a system once closely linked to local feed inputs and nutrient cycles to one in which different stages of the production process are becoming increasingly separated in space [8, 20]. With projected growth in both world meat demand and meat trade expected to rise more than 50% over the next 25years [3], this decoupling of animals from the local resource base has far-reaching implications for both environmental and social systems. Although livestock production has long relied on the intensive use of environmental resources, rapid growth in meat and feed trade has increased the distance between most meat consumers and meat produc- Environ Model Assess DOI 10.1007/s10666-008-9149-3 M. Burke Program on Food Security and the Environment, Stanford University, Encina Hall East 417, Stanford, CA 94305, USA K. Oleson (*) Public Policy Program, Stanford University, Encina Hall East 108, Stanford, CA 94305, USA e-mail: koleson@stanford.edu E. McCullough Economic and Policy Division, Food and Agriculture Organization, Rome, Italy J. Gaskell Interdisciplinary Graduate Program in Environment and Resources, Stanford University, Encina Hall East 417, Stanford, CA 94305, USA