Defining System Boundaries of an Institution Nitrogen Footprint.

A nitrogen (N) footprint quantifies the amount of reactive nitrogen released to the environment and can be measured at different scales. The N footprint of a university includes activities and consumption within its geographic boundaries as well as activities that support the institution. Determining system bounds of an N footprint depends on the institution's mission and provides a common baseline for comparison. A comparison of three scopes of the N footprint, which describe how emissions are directly related to an institution's activities, was conducted for seven institutions. Scopes follow the established definition for the carbon footprint. In this article, the authors propose a new system bounds definition (core campus versus adjunct). Two case studies were explored: how the N footprint of Dickinson College changed with air travel, and how the N footprint of the Marine Biological Laboratory changed with scientific research. Of the three scopes, scope 3 was consistently the largest proportion of the N footprint for all seven institutions. The core campus activities of Dickinson College made up 99 percent of its N footprint, with air travel making up the remaining 1 percent. The Marine Biological Laboratory's core campus activities made up 51 percent of its N footprint and the scientific research made up the remaining 49 percent. Institutions should define system bounds based on their mission and stay consistent with their boundaries following the baseline year. The core campus footprint could be used to compare institution footprints using consistent system bounds. How institutions define their boundaries will impact the recorded amount of nitrogen as well as how the institution will set reduction strategies.

The Nitrogen Footprint Tool Network: A Multi-Institution Program To Reduce Nitrogen Pollution.

Anthropogenic sources of reactive nitrogen have local and global impacts on air and water quality and detrimental effects on human and ecosystem health. This article uses the Nitrogen Footprint Tool (NFT) to determine the amount of nitrogen (N) released as a result of institutional consumption. The sectors accounted for include food (consumption and upstream production), energy, transportation, fertilizer, research animals, and agricultural research. The NFT is then used for scenario analysis to manage and track reductions, which are driven by the consumption behaviors of both the institution itself and its constituent individuals. In this article, the first seven completed institution nitrogen footprint results are presented. The Nitrogen Footprint Tool Network aims to develop footprints for many institutions to encourage widespread upper-level management strategies that will create significant reductions in reactive nitrogen released to the environment. Energy use and food purchases are the two largest sectors contributing to institution nitrogen footprints. Ongoing efforts by institutions to reduce greenhouse gas emissions also help to reduce the nitrogen footprint, but the impact of food production on nitrogen pollution has not been directly addressed by the higher education sustainability community. The Nitrogen Footprint Tool Network found that institutions could reduce their nitrogen footprints by optimizing food purchasing to reduce consumption of animal products and minimize food waste, as well as by reducing dependence on fossil fuels for energy.

Reducing the Nitrogen Footprint of a Small Residential College.

The release of reactive nitrogen contributes to its accumulation in the environment, causing a variety of harmful effects. To measure Dickinson College's contribution to nitrogen pollution, and quantify the potential to reduce its contribution, we calculated the college's nitrogen footprint and simulated the effects of selected nitrogen mitigation measures. The analysis was obtained using the Nitrogen Footprint Tool, developed at the University of Virginia. Food production is by far the largest contributor to Dickinson's footprint, followed by heat and power. Transportation, sewage, and groundskeeping contribute relatively small amounts. Breaking food down into different food categories, meat and fish is the largest source of nitrogen, accounting for two-thirds of the food footprint. Simulations of individual mitigation measures showed that measures targeting food are the most impactful for reducing the college's nitrogen footprint. Two policy scenarios that combine multiple measures, one representing moderate action and the other more aggressive action, were also analyzed. They are projected to reduce Dickinson's footprint by roughly 15 and 25 percent, respectively, while reducing operating costs. Achieving these reductions would require substantial changes in dietary choices by members of the campus community.