@article {88,
	title = {GROSS NITROGEN BALANCES HANDBOOK},
	year = {2007},
	month = {10/2007},
	pages = {24},
	institution = {OECD, EUROSTAT},
	keywords = {agriculture, methodology, nitrogen, nutrient},
	url = {http://www.oecd.org/department/0,3355,en_2649_33793_1_1_1_1_1,00.html},
	author = {OECD}
}
@article {Leip2011b,
	title = {{Farm, land, and soil nitrogen budgets for agriculture in Europe calculated with CAPRI}},
	journal = {Environmental Pollution},
	volume = {159},
	number = {11},
	year = {2011},
	pages = {3243{\textendash}3253},
	abstract = {We calculated farm, land, and soil N-budgets for countries in Europe and the EU27 as a whole using the agro-economic model CAPRI. For EU27, N-surplus is 55 kg N ha -1 yr -1 in a soil budget and 65 kg N 2O-N ha -1 yr -1 and 67 kg N ha -1 yr -1 in land and farm budgets, respectively. NUE is 31{\%} for the farm budget, 60{\%} for the land budget and 63{\%} for the soil budget. NS values are mainly related to the excretion (farm budget) and application (soil and land budget) of manure per hectare of total agricultural land. On the other hand, NUE is best explained by the specialization of the agricultural system toward animal production (farm NUE) or the share of imported feedstuff (soil NUE). Total N input, intensive farming, and the specialization to animal production are found to be the main drivers for a high NS and low NUE. {\textcopyright} 2011 Elsevier Ltd. All rights reserved.},
	keywords = {agriculture, Europe, Nitrogen budgets, Nitrogen use efficiency, Nutrient balances},
	issn = {02697491},
	doi = {10.1016/j.envpol.2011.01.040},
	url = {http://dx.doi.org/10.1016/j.envpol.2011.01.040},
	author = {Leip, Adrian and Britz, Wolfgang and Weiss, Franz and De Vries, Wim}
}
@article {Sutton2011a,
	title = {{Too much of a good thing.}},
	journal = {Nature},
	volume = {472},
	number = {7342},
	year = {2011},
	month = {apr},
	pages = {159{\textendash}61},
	keywords = {agriculture, Agriculture: economics, Animals, Biodiversity, Climate Change, Cost-Benefit Analysis, Diet, Environmental Pollution, Environmental Pollution: adverse effects, Environmental Pollution: analysis, Environmental Pollution: economics, Environmental Pollution: statistics {\&} numerical da, Fertilizers, Fertilizers: analysis, Food Supply, Fossil Fuels, Humans, International Cooperation, Meat, Meat: utilization, nitrogen, Nitrogen Fixation, Nitrogen: adverse effects, Nitrogen: analysis, Nitrogen: economics, Nitrogen: metabolism, Reactive Nitrogen Species, Reactive Nitrogen Species: adverse effects, Reactive Nitrogen Species: analysis, Reactive Nitrogen Species: chemistry, Reactive Nitrogen Species: metabolism},
	issn = {1476-4687},
	doi = {10.1038/472159a},
	url = {http://www.ncbi.nlm.nih.gov/pubmed/21478874},
	author = {Sutton, Mark A. and Oenema, Oene and Erisman, Jan Willem and Leip, Adrian and van Grinsven, Hans and Winiwarter, Wilfried}
}
@article {Leip2019a,
	title = {{Nitrogen Footprints}},
	journal = {Encyclopedia of Ecology},
	volume = {4},
	number = {2012},
	year = {2019},
	pages = {370{\textendash}382},
	publisher = {Elsevier Inc.},
	edition = {2},
	abstract = {N is one of essential element of life on earth, but it contributes in its reactive form to the global environmental problems that are already larger than our earth is able to cope with, and it expected further aggravate (Galloway and Leach, 2016) driven by the increasing demand of food products fuelled by growth of human population, rising incomes and urbanization. The quantification of N footprints at production level can support decision and policy making in the economy, by raising awareness of different stakeholders such as farmers, industrial actors, businesses, governments and scientists on the global threats of anthropogenic activities. These stakeholders have responsibility to reduce the environmental pressures by continuous improvement of the production system through technology and innovation. N footprint is also a tool to inform consumers on the impact of their lifestyle choices on the N pollution, which is essential to share the responsibility in protecting the planet. Raising awareness to all stakeholders and consumers at all levels will help to reduce the N footprint.},
	keywords = {agriculture, Consumption, Energy, Food, Footprints, nitrogen, Production},
	isbn = {9780124095489},
	doi = {10.1016/B978-0-12-409548-9.10753-5},
	url = {http://dx.doi.org/10.1016/B978-0-12-409548-9.10753-5 https://linkinghub.elsevier.com/retrieve/pii/B9780124095489107535},
	author = {Leip, Adrian and Uwizeye, Aimable}
}
