ABSTRACT As climate change becomes more of a reality, individuals to institutions have

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1 Toward Institutional Sustainability: A Nitrogen Footprint for the Marine Biological Laboratory Maggie Notopoulos Skidmore College 14 Mentors: Jim Galloway and Chris Neill ABSTRACT As climate change becomes more of a reality, individuals to institutions have begun to look into lessening their negative impact on the environment. Many people have focused on improving their carbon footprint, or release, into the environment, but there has not been much focus on reducing their nitrogen release. Institutions require large amounts of resources including electricity and food to maintain their daily activities. Food purchases and consumption paired with energy usage have a large negative effect on the environment through large amounts of reactive nitrogen (Nr), all nitrogen compounds other than N 2, associated with their use. Most of the Nr is released to the environment. The amount of Nr that is associated with resource use at an institution is defined as the institution s nitrogen footprint. The Marine Biological Laboratory s nitrogen footprint is 11 MT N for The institution, though, participates in fertilizer-based research primarily in Plum Island, MA, which, if combined with the institution s basic nitrogen footprint, increases it to 16 MT N. Calculating a nitrogen footprint for an institution not only raises awareness to the degree that the institution is influencing the environment, but, by running the nitrogen footprint model through scenarios, it can aid the institution in taking educated steps towards reducing their footprint in the future. If no action is taken on improving the amount of nitrogen released, by 2025, MBL will be releasing 2 MT N more, to total 13 MT N annually (research fertilizer excluded). The footprint reductions from scenarios

2 range in effectiveness by a 1.4% reduction, by replacing 20% of bovine purchases with poultry, to a 29% reduction, by reducing the daily protein intake down to the USDA requirements. Although not a topic of this report, other reductions are possible by decreasing the institution s reliance on fossil fuel combustion (e.g., use of alternative fuels, increased energy efficiency). KEY WORDS: Reactive Nitrogen, Nitrogen Footprint, Sustainability, Fertilizer, Nitrogen Uptake Factors, Virtual Nitrogen, Food Production, Emission Factors, Nitrogen Balance INTRODUCTION The Marine Biological Laboratory (MBL) is an institution driven to protect our planet by learning more about our world and the harmful effects human activities have on our environment. Each year, researchers and students come from across the globe to the MBL facilities to converse and discover more about the earth s wonders, but even their positive intentions are negatively affecting the environment. Daily activities from turning on a light switch to eating lunch, release reactive nitrogen (Nr) into the environment, negatively affecting it from the local to the global scale. Humans should be aware of what our resource usage releases into the environment because of negative repercussions it has on the environment. Thankfully, people are becoming more aware of the trend towards sustainability. Many people, though, look only to reduce their carbon footprint; however, to tackle reducing our effects on the environment, we also need to look at our nitrogen footprint. Humans create reactive nitrogen, all forms of nitrogen except N 2, primarily through two main processes: combustion of fossil fuels and food production (Leach et al, 2012). Reactive nitrogen (Nr) levels are important to manage because these nitrogen 2

3 forms include NOx, which contributes to the formation of tropospheric ozone, and N 2 O, a green house gas (GHG). Not only does excess nitrogen lead to an increase in GHGs, but it also leads to soil acidification, ozone depletion, biodiversity loss, smog and more negative environmental impacts (Galloway et al. 2003). This paper focuses on the release of reactive nitrogen to the environment by the calculation of MBL s nitrogen footprint. Though carbon footprint is a term and concept that has become a household term, the trend towards sustainability has not given nitrogen the spotlight to educate the public of the importance of nitrogen reduction alongside the reduction of carbon release. The University of Virginia (UVA) was the first institution to create a nitrogen footprint model, calculating the release of nitrogen on a non-individual scale, laying the path for additional institutions across the world to follow in their footsteps and create models for their home institutions (Leach et al., unpublished). Previous to their work, only the University of Minnesota (Savanick et al. 2007) had created a nitrogen balance for the institution determining the amount of nitrogen entering and leaving the campus across a year. Though the nitrogen balance covers the same major categories as a nitrogen footprint (i.e. energy usage, food consumption, research animals, and more), it does not directly calculate the institution s nitrogen impact. Furthermore, it does not look into reduction methods for the institution s nitrogen release, which is a vital portion of a nitrogen footprint. Excluding UVA s work, the only nitrogen footprint data available are individual footprints utilizing the online service of the N-Calculator to calculate and compare an individual s food consumption, energy usage, transportation habits and consumerism to averages for individuals from America, 3

4 the Netherlands, and Germany (Leach et al., 2012; N-Print 2011). The program has determined that the average American releases 41 kg N/ yr. The individual footprint though, does not focus as in-depth as an institutional nitrogen footprint, and therefore does not precisely calculate an individual s impact. Energy usage and food production are the major contributors to a nitrogen footprint. The use of energy creates reactive nitrogen primarily through the combustion of fossil fuels (Leach et al. 2012). During food production, the Haber-Bosch process and cultivation of legumes are the primary processes that create reactive nitrogen. Some of this nitrogen enters the system through agricultural use of fertilizers added to the fields, crop-processing waste, livestock waste, and consumer food-waste (Leach et al. unpublished). The small amount of nitrogen that remains contained within the food product, specifically protein, is released through the consumer s waste. Tracking the nitrogen in waste is important because methods of waste disposal can further reduce a nitrogen footprint. My goal is to construct a nitrogen footprint model for the MBL. This model will be used to test scenarios of future resource usage to minimize our output of nitrogen to the environment, while maximizing our benefits from nitrogen. In order to calculate the nitrogen footprint for MBL, I collected data on MBL s fertilizer, research animals, transportation, utilities, food production, food consumption, and food recycling. Fertilizer use to grow food is important to include because reactive nitrogen is applied directly to soils, which introduces significant amounts of N to system. The fertilization process releases 80% of the reactive nitrogen to the environment, since only 20% of reactive nitrogen is contained in the consumer s final food products (Leach 4

5 et al. 2012). Research animals account for part of MBL s nitrogen footprint for two reasons. First, the animal s food contains nitrogen, which is attributed to virtual nitrogen and transportation nitrogen emissions for the shipment of the product. Second, the animal s biomass contains nitrogen and, once it dies, depending on the disposal process, the amount of nitrogen released to the environment can vary. Energy is important to consider due to the combustion of fossil fuels during processes for utilities, including heating and electricity, and in transportation, which adds reactive nitrogen, specifically NOx, into the environment. Processes involving food from the production, transportation, and consumption, also add tremendous amounts of reactive nitrogen to the environment. This can range from agricultural fertilizer usage, combustion of fossil fuels, to the nitrogen content within each meal. Virtual nitrogen, which is factored into the food production, is attributing all the nitrogen that went into creating the product, which includes the fertilizer which helped grow the crops, which fed the animal, which became the food products, as well as the nitrogen content that is within the food product itself. Food recycling (e.g. composting), though, is a way to help reduce MBL s nitrogen footprint. OBJECTIVES The objectives of this project and paper are as follows: 1. To create a nitrogen footprint model for the Marine Biological Laboratory 2. To use the model to calculate MBL s nitrogen footprint 3. To use the model to test scenarios of how specific actions would change MBL s nitrogen footprint. METHODS Due to the pioneering work of the students and faculty of the University of Virginia; my work at the Marine Biological Laboratory is modeled after their work (Leach et al, unpublished). 5

6 DEFINING THE MBL SYSTEM The Marine Biological Laboratory (MBL) is located in Woods Hole, MA. The small institution settled on the edge of Cape Cod has a population that booms in the summer months of June-August, but then decreases to only the staff population, unless a conference ranging from a small graduate school group to a world-wide parasitism conference comes to utilize the institution s space. The year-round population varies, making an exact number of the population unclear. A rough calculation was made utilizing the meals served throughout the year, revealing an 833 person year-round population, or using data from daily MBL staff commuters, 285 people. Staff members live in various areas of Cape Cod, the greater Cape area, and farther distances. Commuters account towards the footprint, but there is no set population for the campus due to its varying size. Furthermore, meals consumed are not reserved for staff members and it is to be noted that staff members will bring meals from outside sources not contained within the MBL system and cannot be attributed to the footprint. For the purposes of this study, I estimate that the population over the year at MBL is <1,000. For most calculations I utilized a population of 833, determined by the number of meals annually served. To determine the MBL geographic location, one needs not only to look at the immediate campus (Figure 1) but also to include the shared facilities [such as the Lillie Library (Figure 1), which is shared with the Woods Hole Oceanographic Institute], the MBL-owned Waterfront Park, MBL owned cottages for summer residents, and MBLrun fertilizer research plots (Note: transportation calculations also include vehicles for the Toolik Lake research station). The footprint model will take into account information 6

7 from all categories: food ordered, consumed and disposed of at the Swope Dining facility, energy usage across all geographic areas and fuel usage for not only staff members, but also MBL-owned vehicles, research animals at the Marine Resource Center (MRC), and fertilizer application at the MBL-owned Waterfront Park as well as MBL scientist run research plots across Massachusetts. Every member and location of MBLrelated facilities contributes to the amount of nitrogen released to the environment, the majority through energy usage and the consumption of food. The calculated nitrogen released for MBL related to purchased electricity, commuting staff members and MBL vehicles, and food (production and transportation) is external to MBL, but still a considered within the institution s footprint. Other external purchases (i.e. office products, research supplies, etc.) are not considered within this initial footprint model. Furthermore, it is to be noted that the human waste from MBL is sent to the Town of Falmouth s Waste Water Treatment Plant (FWWTP), which also treats sewage from other Woods Hole and Falmouth areas (including septic tanks from local residencies). FERTILIZER N fertilizer is used at these locations: 1. Plum Island, MA. MBL researchers, Linda Deegan and colleagues, are participating in a Long Term Ecological Research (LTER) project which moderately-fertilizes two creeks, Sweeney Creek and Clubhead Creek, with sodium nitrate fertilizer to better understand how increased nutrient levels affect watersheds, marsh compositions and more (J. Nelson, MBL, personal communication; Deegan et al., 2012). 2. Martha s Vineyard, MA. MBL researcher, Chris Neill, uses urea to fertilize 15 plots of different sizes to observe biodiversity changes (C. Neill, MBL, personal communication). 3. Waquoit Bay, MA. MBL researcher, Ivan Valiela, uses fertilizer at various levels (low, high, extra high) as well as urea for the Waquoit Bay Land Margin Ecosystems Research project (WBLMER), which are 8 plots used to observe affects of nitrogen loading from coastal watersheds (Valiela 1997). 7

8 4. The institution also uses Chickity Doo Doo fertilizer on the MBL-owned property, specifically the Waterfront Park, for general maintenance (R. Cutler, MBL, personal communication). In Woods Hole, fertilization is restricted to the Waterfront Park (R. Cutler, personal communication). Due to the lack of large vegetation, i.e. trees, which lead to no long-term storage on the property, the average amount of uptake for the area is 0% of the applied Chickity Doo Doo fertilizer (C. Neill, personal communication). In Linda Deegan s work at Plum Island, MA which is a 12-week fertilization project, the uptake factor of nitrogen by the vegetation is 2% due to denitrification, which is then subtracted from the total fertilizer application to determine the net nitrogen release to the environment (Drake et al. 2009). Due to the extreme amount of fertilizer usage for research-based work, there are two current nitrogen footprints created. The variation occurs within the fertilizer category of these footprints: 1) including the Waterfront Park fertilization as well as research fertilization; and 2) excluding any research fertilizer and only combining the Waterfront Park with the other footprint categories as follows. UTILITES Electricity purchased from Direct Energy is generated by 58% Natural Gas, 20% Coal, 1% Oil, and the remaining 21% from sources that do not contribute to a nitrogen release (W. Brosseau, personal communication). MBL-generated energy from combustion of natural gas and diesel fuel is used for bigger sources such as heating, cooling, generator usage, but also smaller energy sources such as fume hood emissions for MBL s various facilities. The NOx emissions due to purchased electricity were determined by multiplying 8

9 the total amount of purchased fuel type (i.e. natural gas, coal, oil) with a NOx emission factor for each respective fuel type. The nitrogen emissions due to MBL generated energy were calculated via the annual BWP AQ AP-TES report by using the recorded NO 2 reported emission and converting the amount to nitrogen emitted. All emissions of nitrogen were converted into comparable kg nitrogen for the footprint. TRANSPORTATION The nitrogen emissions due to staff commuting were calculated from the daily commuting miles (8,330 miles), and amplified up to a 250-day commuting year (R. Cutler, personal communication). The daily miles were calculated by determining the zip code where each staff member lives, taking the central location of that zip code and determining the distance from that central location to MBL s Woods Hole campus and back, in order to calculate one commuting day. Emission factors for N 2 O (USEPA 1991) and NOx (USEPA 1991) were calculated using information for a standard personal vehicle (USDOT et al. 2009; Wenger et al. 2010). The nitrogen release was also calculated for MBL-owned vehicles. Calculations were similar to the aforementioned calculations yet the information on the exact miles driven was a known variable and each vehicle s mpg information was individualized (USEPA 2012), the N 2 O emissions were determined using an updated source (USEPA 2011), and the NOx emissions were also individualized for each vehicle type (USAEPA 1991). RESEARCH ANIMALS 9

10 Research animal data were obtained for the species within the Marine Resource Center (MRC) through David Remsen, the manager of the MRC. The data contained a census of the species, amount in grams of carcass disposal for each species, and information on feed purchases. The majority of feed for the MRC animals is caught at sea requiring only frozen capelin and squid to be purchased (D. Remsen, personal communication). The footprint includes nitrogen released due to carcass disposal and animal food consumption. There are two disposal methods at the MRC: the first is for native animals which are disposed of a mile off shore from the Woods Hole drawbridge (D. Remsen, personal communication). The second method, for non-native animals, is incineration, which contributes NOx emissions due to the nitrogen content within the animal itself, as well as the NOx emissions due to the combustion process (Ramseyer, 2011; USEPA 1995). The NOx emissions were calculated by multiplying the total mass disposed of for each animal by the standard incineration emission factor (USEPA 1995). The nitrogen release for the purchased food was calculated the same way food production (see below) was calculated. FOOD Food data were collected with the assistance of Derrick Saffron and Cheryl Greene of Sodexo. The data were collected from the following companies: Sysco Corporation, Pepsi Beverage Co., Coke Beverage Co, LaRonga Bakery, Costa Produce, Dean Foods (milk and ice cream purchases), and The Clam Man Inc. Each of these companies provided a list of all the food purchases (item, quantity, and weight) MBL made for This information was used to calculate the total mass (kg) of the purchases for over the year. Each food item was then placed into a food category determined by the UN FAO 10

11 food groups (FAO 1994) (Table 1). The protein content was determined based on USDA and FAO food categories averages (USDA 2009). Multi-ingredient food products, such as a Beef, Chicken, and Pork Meatball (Sysco), which is categorized as bovine, poultry, and pigmeat, were divided equally amongst the appropriate categories (USDA 2009). The protein content of the food was determined by multiplying the mass by food category s respective protein content (Table 1). To determine the nitrogen content within the protein, the protein content of the product was multiplied by 16%, the nitrogen content of protein determined by the FAO (FAO 2003). a. FOOD PRODUCTION Nitrogen associated with food production is the sum of the virtual nitrogen released with the nitrogen released through transportation. Virtual nitrogen combines the amount of nitrogen not only within the physical product, but also the amount of nitrogen that went into the food product through its production process. For example, with an egg, there is a certain nitrogen content within the shell, egg whites, and yolk, but to determine the egg s virtual nitrogen, one also needs to consider the nitrogen that went into the ground from the fertilizer dumped on the cropland to grow the corn, which a hen then consumed, which aided in the production of that egg. Though there is only a small amount of fertilizer originally added for food production retained in the final product, the virtual nitrogen calculation combines all the nitrogen that has gone into the production of the food product with the nitrogen of the food product itself for every unit of nitrogen consumed (Leach et al. 2012). These virtual nitrogen factors utilized were from the Leach et al. unpublished factors including food waste (Table 1). To determine the virtual nitrogen for the footprint, the nitrogen consumed was then multiplied by the appropriate category s virtual nitrogen factor. Virtual nitrogen factors assume that the majority of the 11

12 purchased food is collected from conventional farms, which is a safe assumption due to insufficient data on organic farms, large companies (such as Sysco) primary purchases being from conventional farms, and that there was no distinguished farming method otherwise mentioned during data collection. Food categories were grouped together in order to calculate the nitrogen release due to the transportation of the food products. Average food miles for the transportation distance for the produce were used due to the assumption that delivery vehicles make multiple stops at other farms/facilities before arriving at MBL (Hendrickson et al. 1994) (Table 1). Though MBL is a smaller institution, food deliveries were still within large trucks with the cargo capacity of 50,000 lbs (22,700 kg) (USDOT 2011). The trucks fuel efficiency is recorded as 5.1 mpg (24.5L/km) (USDOT 2009), which was used with N 2 O (Wegner et al. 2010) and NOx (USEPA 1991) emission factors in order to calculate the amount of kg nitrogen released through product transportation. In order to complete the food production calculation, the kg N released through the virtual nitrogen was summed with the kg N released for the transportation of the product in order to determine the total kg N released for each purchased food products. b. FOOD CONSUMPTION There is the assumption that meals ordered at Swope were consumed, digested, and excreted within the MBL grounds. Food waste from the consumed, and uneaten, products were calculated with the category s respective food waste factor (Kantor et al. 1997; Leach et al. 2009). A nitrogen removal factor of 91% for a tertiary treatment system was used to calculate the nitrogen leaving the MBL system through waste (S. Wilson, personal connection). The sewage reduction factor of 91% determines that waste 12

13 leaving the system is turned into sludge, which is reused outside the MBL system as energy due to the heat from its incineration process. SCENARIOS I chose to focus on the reduction of food, specifically food production, due to the current footprint s majority of nitrogen release within the food categories. All scenarios run the current model, which excludes research fertilizer. a. BUISNESS AS USUAL (BAU) In order to estimate the impact of the MBL s future nitrogen footprint with no changes implemented, this scenario utilizes the current model with an assumed 3% population growth for the institution. This predicts the MBL nitrogen footprint for the year 2025, which remains consistent with UVA s work. b. FOOD RECYCLING This scenario projects what footprint reductions would occur if 100% of the food waste is composted rather than being disposed, as is currently done. c. MEAT FREE MONDAYS The Meat Free Mondays scenario is run to observe the impact on food production and consumption by replacing meat with alternative protein sources, such as a Veggie Burger, one day a week. The nitrogen reduction from the replacement meal is subtracted from the total footprint. The nitrogen associated with the addition of the alternative food source is then added to the overall footprint. d. CHICKEN FOR BEEF This scenario estimates the reduction of nitrogen released if 20% of beef purchases were replaced with equivalent chicken purchases. Bovine products have a higher virtual nitrogen amount than poultry, affecting food production numbers. This 13

14 option is put in place to reduce the footprint, while continuing to provide a meat-eater friendly meal option. e. REDUCTION OF PROTEIN This scenario reduces the amount of protein intake at Swope to the USDA required daily intake of 52 grams (USDA 2011) from the average daily protein intake at Swope, which is currently 118 grams. Once Swope s daily protein intake was reduced by the factor of nearly seven to the required daily amount, the meat purchases were decreased evenly, while still maintaining the original ratio of meat purchases (e.g. bovine, 18% of meat purchases) (Table 2). The corrected protein intake was used to recalculate total food production and food consumption data. RESULTS CURRENT FOOTPRINT(S) The MBL is currently releasing 16 MT N/yr (16,000 kg N/yr) (Table 3, Figure 2). Excluding the MBL-run fertilizer research, MBL s current footprint is 11 MT N (Table 4, Figure 3). The model including research fertilizer shows that fertilizer contributes to 33% of the footprint. The model, excluding research fertilizer usage, reports fertilizer as one of the smallest footprint categories (0.05%) (Figure 3). Food production contributes the largest amount of nitrogen released for each of the current footprint models, 35% and 52% (current model with research-fertilizer and excluding respectively). Including the research fertilization, utilities is the third largest category; excluding research usage, utilities is the second largest, 28% and 43% respectively. SCENARIOS Running the current model through scenarios, the footprint could be reduced as follows under various conditions: if MBL implements food recycling the footprint could 14

15 be reduced by 2.9%, Meat Free Mondays by 15%, replacing 20% of the beef purchases with poultry by 1.4%, and finally if daily meals were limited to an average protein consumption standardized to the USDA s required intake value, 29% (Table 5, Figure 4). If no changes are made to MBL and the institution increases by 3%, by 2025 the nitrogen footprint will have increased by 17% (Table 5, Figure 4). DISCUSSION QUALITY OF DATA Accounting for every amount of nitrogen released within an institution is a difficult, if not impossible feat; there will always be assumptions and estimates within data. Due to the brief research time period allowed to create the footprint model (a month), there are more assumptions and inaccuracies within my data than otherwise would be present. Furthermore, in determining the protein content of the research animals, a general assumption was made that 2.7% of the animal mass was protein, which is an accurate assumption for fish, but is not as accurate for other species such as jellyfish (Ramseyer 2011). Some data collection relating to food are from 2011 purchases and assumed to be relatively the same for 2012 purchases; however, Sysco data were orders from January-November from 2012 with the December orders from 2011 to fulfill a years worth of purchases. There are also inaccuracies within energy data collected. Commuting staff member information is taken from a central point of the zip code in which the person resides, thus it is not an accurate distance for each staff member, only an assumption. Commuting emissions assumed that all staff members drove a standard vehicle with a mpg of 22.1 and that no public transportation was used. 15

16 There was much debate over the uptake factor for the various fertilized plots. UVA dictated that a standard fertilized lawn, containing trees which have long term storage, has a lawn uptake efficiency of 30%, where MBL s calculations for non-marsh fertilization has an uptake factor of 0%, which was attributed to none of the sites having trees for long term nitrogen storage. This assumption was made for Chris Neill and Ivan Valiela s plots as well. For Linda Deegan s fertilization at Plum Island, the marsh s most accurate uptake factor was determined to be 2%, since there is also no long term storage compared to a tree, yet the vegetation present still retains some nitrogen (Drake et al. 2009). COMPARISIONS Though MBL is only the second institution to complete a nitrogen footprint, we can make a comparison to the first institution, UVA. The initial comparison is that UVA does not have fertilizer research being conducted, or at least not to the degree that MBL is conducting. Because MBL s fertilizer research is a temporary endeavor, the following comparisons will be made between the current MBL footprint, which excludes fertilizer research, and the UVA nitrogen footprint model. A main difference between the footprints is that UVA did not improve its sewage treatment to a tertiary treatment until 2011, while MBL has had that treatment installed since This reduces the food consumption/human waste category of MBL s footprint from 5%, similar to UVA s, to 1% (Figure 3, Figure 5). The major comparisons between the institutions show a mutual dominance by food production and utilities (Figure 3, Figure 5). The total nitrogen release through the virtual nitrogen of numerous purchased food products being a large total, as well as the sum of the emissions for fuel 16

17 usage being a large amount, is responsible for these results. There is also a difference within the research animals comparison due to the difference of protein content in marine animals (MBL) and UVA s terrestrial species. For example, a gelatinous jellyfish has a lower protein content than a rabbit, which is a meat product. Another difference to be noted is that UVA commuting calculations include public transportation, unlike MBL. Further work includes comparisons to a nitrogen balance that the University of Minnesota (UMN) conducted. Though it is not a nitrogen footprint and is not directly calculating UMN s nitrogen impact, its data is still comparable. The large campus of UMN (~60,000 individuals) and UVA (~45,000 individuals) are vastly different to MBL (<1,000 individuals), an institution in the small town of Woods Hole, MA. In comparing MBL s release normalized to population (calculated under the assumption of 833 people present at MBL for the meals served data), a notable difference lies within MBL s fertilizer usage compared to the other institutions (Table 7). This is due to MBL restricting its fertilizing to only a small geographic area unlike many other institutions, which fertilize most of their greens. Another difference is within human waste; this is attributed to MBL having a more efficient tertiary sewage system unlike UVA s initial footprint, and most likely UMN s as well. There is also a difference among research animals data; this, like the difference in UVA s footprint to MBL s footprint, can be attributed to the variation in researched species. MBL has marine animals, such as jellyfish, which have lower protein content than rabbits, like UVA s animals, and/or UMN s agricultural animals, such as cows. STRATEGIES FOR IMPROVEMENT 17

18 The Business as Usual (BAU) scenario calculates, with an assumption of a 3% population growth each year, what the nitrogen footprint would be for MBL if nothing changed on campus in terms of its nitrogen release. This indicated that by 2025 MBL, an environmental institution, would increase its nitrogen release by 2.2 MT N/yr, a 17% increase. It is not an option for institutions to continue to increase their nitrogen releases. There are several ways for an institution to decease its N footprint. I chose to focus on food-related scenarios in order to discover how alterations on food production and consumption would decrease the MBL nitrogen footprint. I did this because meats and vegetable products are the majority of the food production category (both 18% of the overall footprint) (Figure 3). Meat production provides the second largest aspect of the food production category (Table 4). Vegetable products are only 0.1% higher, but these products include every product purchased that is not meat, dairy and eggs, or seafood. This indicates that the nitrogen release of Swope s meat purchases is equivalent to the purchases of nearly all other products. By simply focusing on reducing the amount of meat purchases, MBL s nitrogen footprint in varying ways will be reduced. Under the category of food recycling, Swope used to donate food to a local church, but due to liability issues, that has ceased. There have never been any efforts to create a composting system for Swope. If all the food waste were composted instead of being thrown out, this would reduce the footprint by 2.9% (Table 5). Many institutions, specifically universities, have started to trend towards, one day a week, replacing their meat with a vegetarian protein meal option. The Meat Free 18

19 Mondays scenario investigates if one day a week Swope served non-meat protein options, revealing that it would reduce the annual nitrogen footprint by 15% (Table 5). The Chicken for Beef calculation investigates replacing 20% of the bovine purchases with poultry. Bovine meat has a higher virtual nitrogen factor than poultry, so by simply swapping low-efficiency bovine out for higher-efficiency poultry, MBL s footprint would be reduced by 1.4% (Table 5). The Reduction of Protein scenario was the most impressive to calculate. The USDA states that humans only require a daily protein intake of 52 grams (USDA 2011). The average American, following our over-consumerist nature, intakes 91 grams of protein on average (Fulgoni VL 3 rd 2008). At Swope, daily, we consume on average 118 grams of protein, more than double the required amount. By reducing our purchases to match humans daily protein intake requirement, while maintaining the same ratio of protein product purchases, MBL could reduce its footprint by 3.1 MT N/yr or 29% (Table 5). This shows the importance of education on the impact of food products. The common conception that buying local does not reduce environmental impacts, in terms of nitrogen, to as large a degree as educated behaviors do, such as altering meat purchases, or non-meat protein purchases. Work on the MBL s nitrogen footprint is not complete; there is always room for improvement. Along with improving the aforementioned footprint model s accuracy, energy scenarios should be created to observe what effects environmentally friendly steps, including improved electricity and food sources, reduced reliance on fossil fuels and more, could provide in reducing the footprint. Within the next few years MBL will 19

20 be adding and replacing some of its electricity with renewable energy sources, such as wind power, which could dramatically alter and improve the footprint. This work at MBL is furthers UVA s work on expanding the awareness of nitrogen footprints for an improved and more successful future towards sustainable institutions. Awareness of humans release of reactive nitrogen into the environment is vital in order to reduce the negative environmental impact affecting and destroying our planet, such as smog, ozone depletion, biodiversity loss, and climate change. ACKNOWLEGDMENTS My path to applying to the Semester in Environmental Sciences (SES) was a bit different than the other students. I ve grown up passing through the small seaside town of Woods Hole on my way to Martha s Vineyard, where I ve spent many summers of my life. Since my very first biology class at Skidmore, where the (now) department head made an announcement of this program, I have made it my mission to attend this program. Pursuing it, as I do many passions in my life, with little knowledge of what it actually entails but a determination to achieve my goal nonetheless. As I sit here now after completing this semester-long program, finally allowing myself to reflect back on where my ignorant determination brought me this time, I have a few people to thank. I would first like to thank my parents, Alexis and Alex, for not only pushing me away from following in their lawyer-footsteps, but through our summer vacations, introducing me to this area. Though many of my visits were restricted to the Steam Ship Authority building and parking lots, there would always be the occasional summers when my parents over-planning and fear of traffic landed us at least an hour for our ferry; which provided the opportunity for my sister and I to explore the town, eat at Pie in the 20

21 Sky, and visit the local aquarium. I would especially like to thank my father for having an unpursued passion for the sciences, which he s shared with me since birth. His love of the field paired with his obsessions with the work at WHOI, only further my drive to live within the scientific community here. Furthermore, to thank Jim Galloway and his wife Nancy, thank you for your open hearts paired with an inviting house that rekindled my passion to complete this project with the simple delicious reminder of the holiday season fast approaching. To all the members of the UVA footprint team (especially Jim Galloway, Alley Leach and Ariel Majidi), I cannot thank you enough for the endless help and your personal investments in the project. From chains that could wrap around the world, to the endless time going over every. single. Excel tab. (with the added help of Chris Neill as well), your friendliness and passion for the project is infectious. Derrick Saffron, the dedication to the project you shared was tremendously appreciated. From going through every ordered item with no recorded weight, to dealing with my daily questions; you went above and beyond helping me with the completion of my most difficult and time-consuming category. Finally, I cannot sign off on this work, and this semester, without thanking all the students and staff that made this experience what it was. For all the SESers: Aliza, Alex, Arianna, Ashley, Elizabeth, Jen, Jo, Joo Young, Julia, Kara, Katherine Anne, Kim, Michael, Shelly, Tanner, and Zach, thank you for all the late-night laughs, stress relieving dance parties and music-blasting sessions, poo jokes, and the fantastic nerdy science humor. Our time here will never be forgotten, only cherished, and held as a steppingstone to pursuing our passions in our bright futures. 21

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23 REFERENCES Brosseau, W.. Marine Biological Laboratory, personal communication, November Cutler, R.. Marine Biological Laboratory, personal communication, November Drake D.C., B. J. Peterson, K. A. Galvan, L. A. Deegan, C. Hopkinson, J. M. Johnson, K. Koop-Jakobsen, L. E. Lemay, C. Picard Salt marsh ecosystem biogeochemical responses to nutrient enrichment: a paired 15 N tracer study. Ecological Society of America. 90(9): Deegan, L., D. S. Johnson, R. S. Warren, B. J. Peterson, J. W. Fleeger, S. Fagherazzi, W. M. Wollheim Coastal eutrophication as a driver of salt marsh loss. Nature. 490: [FAO] Food and Agriculture Organization of the United Nations Definition and Classification of Commodities. (April 2011; [FAO] Food and Agriculture Organization of the United Nations Food Energy - Methods of Analysis and Conversion Factors. (26 March 2009; Fulgoni VL 3rd. "Current protein intake in America: analysis of the National Health and Nutrition Examination Survey, " The American Journal of Clinical Nutrition 87.5 (2008): Pubmed.gov. Web. 4 Dec Galloway, J.N., J.D. Aber, J.W. Erisman, S.P. Seitzinger, R.W. Howarth, E.B. Cowling, and B.J. Cosby The Nitrogen Cascade Bioscience 53: Galloway, J.N., A.R. Townsend, J.W. Erisman, M. Bekunda, Z. Cai, J.R. Freney, L.A. Martinelli, S.P. Seitzinger, and M.A. Sutton Transformation of the Nitrogen Cycle: Recent Trends, Questions, and Potential Solutions. Science 320 (5878): Hendrickson, J Energy Use in the U.S. Food System: A Summary of Existing Research and Analysis. (14 March, 2009; uploads/2008/07/energyuse.pdf) Kantor L, Lipton K, Manchester A, Oliveira V Estimating and addressing America s food losses. Food Review 20: Leach, A. M., A.N. Majidi, J.N. Galloway, A.J. Greene. Manuscript. Towards Institutional Sustainability a Nitrogen Footprint Model for a University. 23

24 Leach, A. M., J. N. Galloway, A. Bleeker, J. W. Erisman, R. Kohn, and J. Kitzes A nitrogen footprint model to help consumers understand their role in nitrogen losses to the environment. Environmental Development 1: Neill, C.. Director, Ecosystems Center, MBL, personal communication, November Nelson, J.. Plum Island Research with Linda Deegan: Ecosystems Center, MBL, personal communication, November "N Foorprint Calculator." N-Print. Web. 21 Nov Ramseyer, Laurel J. Predicting Whole-Fish Nitrogen Content from Fish Wet. Weight Using Regression Analysis. 09 Jan Remsen, D. Manager, Marine Resources Department, personal communication, November 2012 Resource Media Nitrogen News Savanick, S "Guidelines for College-Level Nitrogen Budgeting." Science Education Resource Center. Carleton College. Web. Savanick, S, L Baker, J Perry Case study for evaluating campus sustainability: nitrogen balance for the University of Minnesota. Urban Ecosystems 10: [USDA] Department of Agriculture Food Groups: How much food from the Protein Foods Group is needed daily? (8 December 2012, [USDA] US Department of Agriculture. 2009a. USDA National Nutrient Database for Standard Reference. (20 February 2009; [USEPA] US Department of Energy: Energy Efficiency & Renewable Energy Fuel Economy. ( 28 November 2012; [USEPA] Emission Factors for Greenhouse Gas Inventories (12 November 2012; [USEPA] US Environmental Protection Agency AP-42: Compilation of Air Pollutant Emission Factors, Volume 2: Mobile Sources. (20 February 2009; [USEPA] United States. Environmental Protection Agency. 2.3 Medical Waste Incineration. N.p., n.d. Web ( 26 November 2012; 24

25 Valiela, I., G. Collins, J. Kremer, K. Lajtha, M. Geist, B. Seely, J. Brawley, And C. H. Sham Nitrogen loading from coastal watersheds to receiving estuaries: new method and application. Ecological Society of America. 7(2): Wilson, S. Rivanna Water and Sewer Authority, personal communication conducted by UVa, 12 August Nitrogen Cycle. The Environmental Literacy Council. Web. 25

26 Table 1. Factors used for Food-related calculations. Protein Virtual N content a Factor b Food Miles c Average % Food Waste d Food Category Food Product kg N lost / kg protein / kg kg N food consumed mi % Bovine % Meat Pigmeat % Poultry % Cheese % Dairy & eggs Eggs % Milk % Seafood Fish % Beverage % Cereals % Fruits % Nuts % Oilcrops % Vegetable Pulses % products Spices % Starchy roots % Stimulants % Sugarcrops % Vegetables % a. FAOSTAT b. Factors which calculate the total reactive nitrogen released to the environment during food production for each unit of N consumed (Leach et al. 2012). c. Hendrickson 1994 d. Kantor

27 Table 2. Percent of purchases divided among protein-rich products. Food product % of Protein Purchases Poultry 17.10% Bovine 18.44% Pigmeat 8.82% Milk 16.60% Cheese 9.95% Eggs 9.37% Fish, Seafood 19.73% 27

28 Table 3. The Current Nitrogen Footprint for the Marine Biological Laboratory in 2012 by category including data on MBL-run fertilizer research projects. Category Type Total N Released (kg N) % of Total Meat 1, % Food Dairy & eggs 1, % Seafood % Vegetable products 1, % Food Consumption/ Human Waste Sewage % Utilities Electricity 3, % Heating, other % Transportation MBL Vehicles % Commuting % Fertilizer Fertilizer 5, % Research Animals Research Animals % Total 15,838 kg N 28

29 Table 4. The Current Nitrogen Footprint for the Marine Biological Laboratory in 2012 by category excluding data on MBL-run fertilizer research projects. Total N Sector Type Released (kg N) % of Total Meat 1, % Food Dairy & eggs 1, % Seafood % Vegetable products 1, % Food Consumption/ Human Waste Sewage % Utilities Electricity 3, % Heating, other % Transportation MBL Vehicles % Commuting % Fertilizer Fertilizer % Research Animals Research Animals % Total 10,599 kg N 29

30 Table 5. A summary of the affects of running the Marine Biological Laboratory s nitrogen footprint model through scenarios. Increase/Reduc % Scenario Category Effected tion Inc./Red. Business As Usual (2025) Increase 17.21% Food Production, Food Consumption, Transportation Food Recycling Reduction 2.90% Food Production Meat Free Mondays Reduction 14.46% Food Production & Food Consumption Chicken for Beef Reduction 1.38% Food Production & Food Consumption Reduce of Protein Intake Reduction 29.43% Food Production & Food Consumption 30

31 Table 6. The Current Nitrogen Footprint for the University of Virginia in Sector Type Total N Released (kg N) % of Total Meat 111, % Food Dairy & eggs 53, % Seafood 3, % Vegetable products 39, % Food Consumption/ Human Waste Sewage 23, % Utilities Electricity 198, % Heating, other 37, % Transportation Public transit 4, % Commuting 19, % Fertilizer Fertilizer 2, % Research Animals Research Animals 20, % Total 514,835 kg N 31

32 Table 7. Comparison of the nitrogen released to the University of Virginia s (UVA) nitrogen footprint and comparable activities at the University of Minnesota (UMN). It is to be noted that the size of UVA and UMN are dramatically larger in regards to population, grounds, and facilities, than MBL. MBL normalized population is determined using the population number, 833 individuals, derived from the numbers of meals served annually at Swope. UMN (metric tons N) UVA (metric tons N) MBL (metric tons N) UMN Normalized to population (kg N/person) UVA Normalized to population (kg N/person) MBL Normalized to population (kg N/person) Human waste Heat and electricity Transport Research animals Fertilizer

33 Figure 1. MBL Main Campus map. Note that the MBL-owned summer cottages and field sites are not included in this map. 33

34 Figure 2. The Current Nitrogen Footprint for the Marine Biological Laboratory in 2012 by category including data on MBL-run fertilizer research projects. Research Animals, 0.5% Fertilizer, 33% Food Production, 35% Transportation, 3% Utilities, 28% Food Consumption/ Human Waste, 1% 34

35 Figure 3. The Current Nitrogen Footprint for the Marine Biological Laboratory in 2012 by category excluding data on MBL-run fertilizer research projects. MBL Vehicles; 0.01% Heating, other, 5.5% Commuting, 3.9% Fertilizer, 0.1% Research Animals, 0.7% Meat, 18.0% Dairy & eggs, 11.7% Electricity, 36.9% Seafood, 4.2% Vegetable products, 18.1% Food Consumption/H uman Waste; 1% 35

36 N Footprint (metric tons N) Notopoulos MBL Nitrogen Footprint Figure 4. The Impact of scenarios on the nitrogen footprint of the Marine Biological Laboratory Research Animals Fertilizer Transportation 6 Utilities 4 2 Food Consumption/ Human Waste 0 Current BAU (2025) Food Recycling Meat Free Mondays Chicken for Beef Reduction of Protein Food Production 36

37 Figure 5. The Nitrogen Footprint for the University of Virginia in 2010 by sector. Commuting, 3.8% Public transit, 0.9% Fertilizer, 0.5% Research Animals, 4.0% Heating, other, 7.3% Meat, 21.7% Dairy & eggs, 10.3% Electricity, 38.5% Vegetable products, 7.6% Seafood, 0.7% Food Consumption/H uman Waste ; 4.6% 37