@article {73,
	title = {A detailed ammonia emission inventory for Denmark},
	journal = {Atmospheric Environment},
	volume = {35},
	year = {2001},
	abstract = {This paper describes the method used to create an ammonia inventory for Denmark and presents the emission factors used and their justi"cation. The total Danish emission for 1996 was 92,700 t NH4-N, with agriculture accounting for nearly 99\%. Emissions from animal manure accounted for 76\% of agricultural emissions. We conclude that there will be a continued demand for inventories based on emission factors, despite their lack of physical and chemical realism, but that they will become more complex. This will place increased demands on the statistical information available and on the knowledge of the underlying science.},
	keywords = {EPNB},
	author = {Hutchings, N. J and Sommer, S. G and Andersen, J. M and Asman, W. A. H}
}
@article {75,
	title = {Processes controlling ammonia emission from livestock slurry in the field},
	journal = {European Journal of Agronomy},
	volume = {19},
	year = {2003},
	pages = {465-486},
	abstract = {The processes of NH3 emission from field-applied slurry are reviewed and their relative importance assessed. In achieving this objective, the study served to focus on a number of features that have not previously been highlighted. These include the effect of the size of the area to which slurry is applied, the interaction between solar radiation input and wind speed, the role of the solid chemistry and the interaction between slurry NH4 and the slurry/soil cation exchange capacity (CEC). The most important processes controlling NH3 volatilisation were considered to be turbulent and molecular diffusion in the atmosphere, meteorological processes controlling evaporation and surface temperature, the ion production and buffering processes controlling the pH of the slurry/soil liquid, the solid chemistry that
determines precipitation of NH4  to slurry dry matter, the physical processes controlling the movement of slurry liquid into and within the soil, and the interaction of slurry liquid with soil CEC.},
	keywords = {EPNB},
	author = {Sommer, S. G and Genermont, S and Cellier, P and Hutchings, N. J and Olesen, J. E, Morvan, T}
}
@article {66,
	title = {Reducing nitrogen surplus from dairy farms. Effects of feeding and management.},
	journal = {Livestock Production Science},
	year = {2003},
	pages = {165-178},
	abstract = {The objective of the present paper is to review the factors which can affect N flow and surplus both at farm and at cow
level in order to point out areas with scope for future improvement. Special attention is given to management factors and
feeding. Besides information from the literature the paper is based on meta-analyses of our own and published results. With
regard to effects of production systems, mainly Danish surveys have been chosen as examples demonstrating the effects
obtained under practical conditions. A positive correlation between stocking rate and N surplus per hectare at farm gate level
is demonstrated, but there is also a considerable variation in N surplus per hectare at a given stocking rate. A number of
factors influencing N surplus and loss have been identified, and their impact on N surplus and production efficiency has been
estimated. N excretion per animal is an important factor for N turnover at farm level. Analysis of herd data indicates that
feeding strategy, breed and milk yield, together with energy conversion and the protein content of the diet, are important
factors explaining N excretion and N efficiency of cows. Reduction of N intake by optimal synchronisation of energy and
protein supply over time, especially in pasture-based systems, is one way of reducing N excretion from cows. Furthermore,
the ideal profile of absorbed amino acids should be identified, and models to estimate amino acid supply to the intestine
should be further improved. The effect of reducing N excretion from cows has to be evaluated at farm level as manure is
used as fertiliser for crop production. Overall, it seems possible to reduce the N surplus through better management and
feeding without reducing production efficiency.},
	keywords = {EPNB},
	author = {Borsting, C. F and Kristensen, T and Misciattelli, L and Hvelplund, T and Weisbjerg, M. R}
}
@article {71,
	title = {A whole-farm assessment of the efficacy of slurry acidification in reducing ammonia emissions},
	journal = {European Journal of Agronomy},
	volume = {28},
	year = {2007},
	pages = {148-154},
	abstract = {Livestock slurry in animal houses, in manure stores and applied on fields is in Denmark the most important source of ammonia (NH3) in the atmosphere. The emitted NH3 is a source of NH3 and ammonium (NH4 +) deposition, which causes eutrophication of N-deficient ecosystems and may form NH4 +-based particles in the air, which are a risk to health. This study examines the reductions in NH3 emissions from pig houses, manure stores and manure applied in the field achieved by acidifying the slurry in-house. Sulphuric acid was used to acidify pig slurry to pH < 6 and the system was constructed is such a way as to prevent foaming in the animal house as well as during storage. Acidification of the pig slurry reduced the NH3 emission from pig houses by 70\% compared with standard techniques. Acidification reduced NH3 emission from stored slurry to less than 10\% of the emission from untreated slurry, and the NH3 emission from applied slurry was reduced by 67\%. The mineral fertilizer equivalent (MFE) of acidified slurry was 43\% higher compared with the MFE of untreated slurry when applied to the soil. The odour emission from the slurry was not affected significantly by the treatment. The slurry acidification system is approved Best Available Technology (BAT) in Denmark.},
	keywords = {EPNB},
	author = {Kai, P and Pedersen, P and jensen, J. E and Hansen, M. N and Sommer, S. G}
}
@article {65,
	title = {Emissions of gaseous nitrogen species from manure management: A new approach},
	journal = {Environmental Pollution},
	year = {2008},
	pages = {488-497},
	abstract = {A procedure for the assessment of emissions of nitrogen (N) species (ammonia, nitrous oxide, nitric oxide, di-nitrogen) from the manure
management system is developed, which treats N pools and flows including emissions strictly according to conservation of mass criteria. As
all relevant flows in the husbandry of mammals are depicted, the methodology is considered a Tier 3 approach in IPCC terminology or a detailed
methodology in UN ECE terminology. The importance of accounting for all N species is illustrated by comparing emission estimates obtained
using this approach with those obtained from the application the present detailed/Tier 2 methodology.},
	keywords = {EPNB},
	author = {Daemmgen, U and Hutchings, N. J}
}
@inbook {Leip2011d,
	title = {{Integrating nitrogen fluxes at the European scale}},
	booktitle = {European Nitrogen Assessment},
	year = {2011},
	pages = {345{\textendash}376},
	publisher = {Cambridge University Press},
	organization = {Cambridge University Press},
	chapter = {16},
	address = {Cambridge, UK},
	keywords = {mypublications},
	url = {http://www.nine-esf.org/ENA-Book},
	author = {Leip, Adrian and Achermann, Beat and Billen, Gilles and Bleeker, Albert and Bouwman, Alexander F and De Vries, Wim and Dragosits, Ulli and D{\"o}ring, Ulrike and Fernall, Dave and Geupel, Markus and Heldstab, J{\"u}rg and Johnes, Penny and Le Gall, Anne Christine and Monni, Suvi and Neve{\v c}e{\v r}al, Rostislav and Orlandini, Lorenzo and Prud{\textquoteright}homme, Michel and Reuter, Hannes I and Simpson, David and Seufert, G{\"u}nther and Spranger, Till and Sutton, Mark A. and van Aardenne, John and Vo{\ss}, Maren and Winiwarter, Wilfried},
	editor = {Sutton, Mark and Howard, Clare and Erisman, Jan Willem and Billen, Gilles and Bleeker, Albert and van Grinsven, Hans and Grennfelt, Peringe and Grizzetti, Bruna}
}
@article {Winiwarter2014a,
	title = {{A European perspective of innovations towards mitigation of nitrogen-related greenhouse gases}},
	journal = {Current Opinion in Environmental Sustainability},
	volume = {9-10},
	year = {2014},
	pages = {37{\textendash}45},
	publisher = {Elsevier B.V.},
	abstract = {Technology design and effectiveness studies available in the scientific literature demonstrate future mitigation potentials of nitrogen-related greenhouse gases. Here we investigate {\textquoteright}innovations{\textquoteright} influencing such emissions. These innovations mainly address agriculture: reduced meat diets, urban gardening, genetically modified crops, and precision farming, but also more distant options such as vertical farming and cultured meat production, that is, indoor agriculture. While the latter approaches, which allow full management of effluents, seem very promising in terms of emission control, the cost estimates available would rule out any practical relevance. Technologies that currently seem more realistic offer much smaller mitigation potential. Information on energy need, greenhouse gas emissions, and land requirements feed into a semi-quantitative assessment, which delivers information in a format useful for existing European policy tools. {\textcopyright} 2014 Elsevier B.V.},
	issn = {18773435},
	doi = {10.1016/j.cosust.2014.07.006},
	url = {http://dx.doi.org/10.1016/j.cosust.2014.07.006},
	author = {Winiwarter, Wilfried and Leip, Adrian and Tuomisto, Hanna L. and Haastrup, Palle}
}
@article {Leip2014b,
	title = {{Nitrogen-neutrality: a step towards sustainability}},
	journal = {Environmental Research Letters},
	volume = {9},
	number = {11},
	year = {2014},
	month = {nov},
	pages = {115001},
	publisher = {IOP Publishing},
	keywords = {Footprint, mypublications, nitrogen},
	issn = {1748-9326},
	doi = {10.1088/1748-9326/9/11/115001},
	url = {http://stacks.iop.org/1748-9326/9/i=11/a=115001?key=crossref.e00563c757c6f69d0f81a98a7c54fa9c},
	author = {Leip, Adrian and Leach, Allison M. and Musinguzi, Patrick and Tumwesigye, Trust and Olupot, Giregon and Stephen Tenywa, John and Mudiope, Joseph and Hutton, Olivia and Cordovil, Claudia M.d.S. and Bekunda, Mateete and Galloway, James N.}
}
@book {Westhoek2015,
	title = {{Nitrogen on the Table: The influence of food choices on nitrogen emissions and the European environment. (European Nitrogen Assessment Special Report on Nitrogen and Food.)}},
	number = {April},
	year = {2015},
	pages = {1{\textendash}5},
	publisher = {Centre for Ecology {\&} Hydrology},
	organization = {Centre for Ecology {\&} Hydrology},
	address = {Edinburgh, UK},
	isbn = {9781906698515},
	url = {https://www.clrtap-tfrn.org/sites/clrtap-tfrn.org/files/documents/Nitrogen_on_the_Table_Report_WEB.pdf},
	author = {Westhoek, Henk and Lesschen, J.P. Jan Peter and Leip, Adrian and Rood, Trudy and Wagner, Susanne and De Marco, A. and Murphy-bokern, Donal and Palli{\`e}re, C. and Howard, Clare M and Oenema, Oene and Sutton, Mark A. and Marco, De}
}
@article {Hutton2017,
	title = {{Toward a nitrogen footprint calculator for Tanzania}},
	journal = {Environmental Research Letters},
	volume = {12},
	number = {3},
	year = {2017},
	abstract = {{\textcopyright} 2017 IOP Publishing Ltd.We present the first nitrogen footprint model for a developing country: Tanzania. Nitrogen (N) is a crucial element for agriculture and human nutrition, but in excess it can cause serious environmental damage. The Sub-Saharan African nation of Tanzania faces a two-sided nitrogen problem: while there is not enough soil nitrogen to produce adequate food, excess nitrogen that escapes into the environment causes a cascade of ecological and human health problems. To identify, quantify, and contribute to solving these problems, this paper presents a nitrogen footprint tool for Tanzania. This nitrogen footprint tool is a concept originally designed for the United States of America (USA) and other developed countries. It uses personal resource consumption data to calculate a per-capita nitrogen footprint. The Tanzania N footprint tool is a version adapted to reflect the low-input, integrated agricultural system of Tanzania. This is reflected by calculating two sets of virtual N factors to describe N losses during food production: one for fertilized farms and one for unfertilized farms. Soil mining factors are also calculated for the first time to address the amount of N removed from the soil to produce food. The average per-capita nitrogen footprint of Tanzania is 10 kg N yr-1. 88{\%} of this footprint is due to food consumption and production, while only 12{\%} of the footprint is due to energy use. Although 91{\%} of farms in Tanzania are unfertilized, the large contribution of fertilized farms to N losses causes unfertilized farms to make up just 83{\%} of the food production N footprint. In a developing country like Tanzania, the main audiences for the N footprint tool are community leaders, planners, and developers who can impact decision-making and use the calculator to plan positive changes for nitrogen sustainability in the developing world.},
	keywords = {nitrogen, nitrogen footprint, Sub-Saharan Africa, Tanzania},
	issn = {17489326},
	doi = {10.1088/1748-9326/aa5c42},
	author = {Hutton, M.O. and Leach, Allison M. and Leip, Adrian and Galloway, James N. and Bekunda, M. and Sullivan, C. and Lesschen, J.P.}
}
@article {Zurek2018,
	title = {{Assessing Sustainable Food and Nutrition Security of the EU Food System {\textemdash} An Integrated Approach}},
	journal = {Sustainability},
	volume = {10},
	number = {11},
	year = {2018},
	pages = {4271},
	doi = {10.3390/su10114271},
	author = {Zurek, Monika and Hebinck, Aniek and Leip, Adrian and Vervoort, Joost and Kuiper, Marijke and Garrone, Maria and Havlik, Petr and Heckelei, Thomas and Hornborg, Sara and Ingram, John and Kuijsten, Anneleen and Shutes, Lindsay and Geleijnse, Johanna M and Terluin, Ida and van{\textquoteright}t Veer, Pieter and Wijnands, Jo and Zimmermann, Andrea and Achterbosch, Thom J. and Havl, Petr}
}
@article {Parodi2018a,
	title = {{The potential of future foods for sustainable and healthy diets}},
	journal = {Nature Sustainability},
	volume = {1},
	number = {12},
	year = {2018},
	pages = {782{\textendash}789},
	publisher = {Springer US},
	abstract = {Altering diets is increasingly acknowledged as an important solution to feed the world{\textquoteright}s growing population within the planetary boundaries. In our search for a planet-friendly diet, the main focus has been on eating more plant-source foods, and eating no or less animal-source foods, while the potential of future foods, such as insects, seaweed or cultured meat has been underexplored. Here we show that compared to current animal-source foods, future foods have major environmental benefits while safeguarding the intake of essential micronutrients. The complete array of essential nutrients in the mixture of future foods makes them good-quality alternatives for current animal-source foods compared to plant-source foods. Moreover, future foods are land-efficient alternatives for animal-source foods, and if produced with renewable energy, they also offer greenhouse gas benefits. Further research on nutrient bioavailability and digestibility, food safety, production costs and consumer acceptance will determine their role as main food sources in future diets.},
	issn = {23989629},
	doi = {10.1038/s41893-018-0189-7},
	url = {http://dx.doi.org/10.1038/s41893-018-0189-7 http://www.nature.com/articles/s41893-018-0189-7},
	author = {Parodi, Alejandro and Leip, Adrian and De Boer, I. J.M. M. and Slegers, P. M. and Ziegler, F. and Temme, E. H.M. M. and Herrero, M. and Tuomisto, Hanna L. and Valin, H. and Van Middelaar, C. E. and Van Loon, J. J.A. A. and van Zanten, Hannah H. E.}
}
@article {Vanham2019a,
	title = {{Environmental footprint family to address local to planetary sustainability and deliver on the SDGs}},
	journal = {Science of The Total Environment},
	volume = {693},
	number = {June},
	year = {2019},
	month = {jul},
	pages = {133642},
	publisher = {Elsevier B.V},
	abstract = {The number of publications on environmental footprint indicators has been growing rapidly, but with limited efforts to integrate different footprints into a coherent framework. Such integration is important for comprehensive understanding of environmental issues, policy formulation and assessment of trade-offs between different environmental concerns. Here, we systematize published footprint studies and define a family of footprints that can be used for the assessment of environmental sustainability. We identify overlaps between different footprints and analyse how they relate to the nine planetary boundaries and visualize the crucial information they provide for local and planetary sustainability. In addition, we assess how the footprint family delivers on measuring progress towards Sustainable Development Goals (SDGs), considering its ability to quantify environmental pressures along the supply chain and relating them to the water-energy-food-ecosystem (WEFE) nexus and ecosystem services. We argue that the footprint family is a flexible framework where particular members can be included or excluded according to the context or area of concern. Our paper is based upon a recent workshop bringing together global leading experts on existing environmental footprint indicators.},
	keywords = {Environmental footprint, Environmental footprint assessment, Family, Footprint, Footprint family, Planetary boundaries},
	issn = {00489697},
	doi = {10.1016/j.scitotenv.2019.133642},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0048969719335673 https://doi.org/10.1016/j.scitotenv.2019.133642},
	author = {Vanham, Davy and Leip, Adrian and Galli, Alessandro and Kastner, Thomas and Bruckner, Martin and Uwizeye, Aimable and van Dijk, Kimo and Ercin, Ertug and Dalin, Carole and Brand{\~a}o, Miguel and Bastianoni, Simone and Fang, Kai and Leach, Allison M. and Chapagain, Ashok and Van der Velde, Marijn and Sala, Serenella and Pant, Rana and Mancini, Lucia and Monforti-Ferrario, Fabio and Carmona-Garcia, Gema and Marques, Alexandra and Weiss, Franz and Hoekstra, Arjen Y.}
}
@article {AdrianLeip,
	title = {{The value of manure - manure as co-product in life cycle assessment}},
	journal = {Journal of Environmental Management},
	volume = {241},
	number = {March},
	year = {2019},
	month = {jul},
	pages = {293{\textendash}304},
	publisher = {Elsevier},
	keywords = {Allocation, Fertilizer, Life cycle assessment, Livestock supply chains, Manure, Nutrients},
	issn = {03014797},
	doi = {10.1016/j.jenvman.2019.03.059},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S0301479719303627},
	author = {Leip, Adrian and Ledgart, Stewart and Uwizeye, Aimable and Palhares, Julio C.P. and Aller, Fernanda and Amon, Barbara and Binder, Michael and Cordovil, Claudia M.d.S. and Dong, Hongming and Fusi, Alessandra and Helin, Janne and H{\"o}rtenhuber, Stefan and Hristov, Alexander N. and Koelsch, Richard and Liu, Chunjiang and Masso, Cargele and Nkongolo, Nsalambi V. and Patra, Amlan K. and Redding, Matthew R. and Rufino, Mariana C. and Sakrabani, Ruben and Thoma, Greg and Vert{\`e}s, Fran{\c c}oise and Wang, Ying and Ledgard, Stewart and Uwizeye, Aimable and Palhares, Julio C.P. and Aller, M. Fernanda and Amon, Barbara and Binder, Michael and Cordovil, Claudia M.d.S. and De Camillis, Camillo and Dong, Hongming and Fusi, Alessandra and Helin, Janne and H{\"o}rtenhuber, Stefan and Hristov, Alexander N. and Koelsch, Richard and Liu, Chunjiang and Masso, Cargele and Nkongolo, Nsalambi V. and Patra, Amlan K. and Redding, Matthew R. and Rufino, Mariana C. and Sakrabani, Ruben and Thoma, Greg and Vert{\`e}s, Fran{\c c}oise and Wang, Ying}
}
@article {Carlo,
	title = {{Sustainable food protein supply reconciling human and ecosystem health: A Leibniz Position}},
	journal = {Global Food Security},
	volume = {25},
	year = {2020},
	month = {jun},
	pages = {100367},
	keywords = {corresponding author, s},
	issn = {22119124},
	doi = {10.1016/j.gfs.2020.100367},
	url = {https://linkinghub.elsevier.com/retrieve/pii/S2211912420300201},
	author = {Weindl, Isabelle and Ost, Mario and Wiedmer, Petra and Schreiner, Monika and Neugart, Susanne and Klopsch, Rebecca and K{\"u}hnhold, Holger and Kloas, Werner and Henkel, Ina M. and Schl{\"u}ter, Oliver and Bu{\ss}ler, Sara and Bellingrath-Kimura, Sonoko D. and Ma, Hua and Grune, Tilman and Rolinski, Susanne and Klaus, Susanne}
}
@article {geupel_national_2021,
	title = {A {National} {Nitrogen} {Target} for {Germany}},
	journal = {Sustainability},
	volume = {13},
	number = {3},
	year = {2021},
	pages = {1121},
	abstract = {The anthropogenic nitrogen cycle is characterized by a high complexity. Different reactive nitrogen species (NH3, NH4+, NO, NO2, NO3-, and N2O) are set free by a large variety of anthropogenic activities and cause numerous negative impacts on the environment. The complex nature of the nitrogen cycle hampers public awareness of the nitrogen problem. To overcome this issue and to enhance the sensitivity for policy action, we developed a new, impact-based integrated national target for nitrogen (INTN) for Germany. It is based on six impact indicators, for which we derived the maximum amount of nitrogen losses allowed in each environmental sector to reach related state indicators on a spatial average for Germany. The resulting target sets a limit of nitrogen emissions in Germany of 1053 Gg N yr-1. It could serve as a similar means on the national level as the planetary boundary for reactive nitrogen or the 1.5 {\textopenbullet}C target of the climate community on the global level. Taking related uncertainties into account, the resulting integrated nitrogen target of 1053 Gg N yr-1 suggests a comprehensible INTN of 1000 Gg N yr-1 for Germany. Compared to the current situation, the overall annual loss of reactive nitrogen in Germany would have to be reduced by approximately one-third.},
	issn = {2071-1050},
	doi = {10.3390/su13031121},
	url = {https://www.mdpi.com/2071-1050/13/3/1121},
	author = {Geupel, Markus and Heldstab, J{\"u}rg and Sch{\"a}ppi, Bettina and Reutimann, Judith and Bach, Martin and H{\"a}u{\ss}ermann, Uwe and Knoll, Lukas and Klement, Laura and Breuer, Lutz}
}
@article {236,
	title = {Nitrogen Opportunities for Agriculture, Food \& Environment: UNECE Guidance Document on Integrated Sustainable Nitrogen Management},
	year = {2022},
	type = {Natalie},
	isbn = {978-1-906698-78-2},
	author = {Mark Sutton and Clare M. Howard and Kate E. Mason and Will Brownlie and Claudia Cordovil}
}
@article {bach_reactive_nodate,
	title = {Reactive nitrogen flows in {Germany} 2010 - 2014 ({DESTINO} {Report} 2)},
	year = {Submitted},
	pages = {152},
	abstract = {Emissions of reactive nitrogen give rise to a wide range of environmental problems. In order to develop reduction measures it is necessary to quantify sources, sinks and flows of Nr, and as part of the Convention on Long-Range Transboundary Air Pollution (CLTRAP) it was agreed in the Gothenburg Protocol to construct national nitrogen budgets. The {\textquotedblleft}Guidance document on national nitrogen budgets{\textquotedblright} of the Economic Commission for Europe forms the starting point for this task. The Nr flows are determined for the following pools: {\textquotedblleft}Atmosphere{\textquotedblright}, {\textquotedblleft}Energy and Fuels{\textquotedblright}, {\textquotedblleft}Material and products in industry{\textquotedblright}, {\textquotedblleft}Humans and settlements{\textquotedblright}, {\textquotedblleft}Agriculture{\textquotedblright}, {\textquotedblleft}Forest and semi-natural vegetation{\textquotedblright}, {\textquotedblleft}Waste{\textquotedblright}, and {\textquotedblleft}Hydrosphere{\textquotedblright}, as well as for the {\textquotedblleft}Trans-boundary N-flows{\textquotedblright} (imports and exports). The N-flows are taken directly from statistical reports, publications, etc., or are calculated as the product of the quantity of transported or converted substance and the mean nitrogen contents. Some 150 N-flows are described, and the uncertainty of the results is graded in four levels from {\textquotedblleft}very low{\textquotedblright} to {\textquotedblleft}high{\textquotedblright}. In Germany, approximately 6275 kt Nr is introduced into the nitrogen cycle every year (mean value from 2010 to 2014), of 43 \% is by ammonia synthesis. Domestic extraction of nitrogenous fossil fuels (lignite, coal, crude oil) and imports contribute 2335 kt N a-1. Natural nitrogen fixation converts 308 kt N a-1 into organically bound nitrogen. Conversely, processes involving the combustion of fossil fuels and regenerative fuels and the refining of crude oil to mineral oil products result in 2711 kt N a-1 being transformed to N2. In waters, soils, and wastewater treatment plants, denitrification leads to the release of 1107 kt N a-1 as molecular nitrogen. Via the atmosphere and hydrosphere, Germany exports 745 kt N a-1 to neighbouring countries and the coastal waters. The changes in N-stock in soils have to date only been determined for forest soils, where they are 293 kt N a-1. On balance, reactive nitrogen totalling 1627 kt N is released in Germany every year, with negative impacts on the ecosystems and their functions. The national nitrogen budget involves considerable uncertainties, and this should be taken into consideration when interpreting the results.},
	author = {Bach, Martin and H{\"a}u{\ss}ermann, Uwe and Klement, Laura and Knoll, Lukas and Breuer, Lutz and Weber, Tatyana and Fuchs, Stefan and Heldstab, J{\"u}rg and Reutimann, Judith}
}
