{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T00:57:58Z","timestamp":1776733078257,"version":"3.51.2"},"reference-count":96,"publisher":"Public Library of Science (PLoS)","issue":"2","license":[{"start":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T00:00:00Z","timestamp":1739404800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norwegian Research Council","doi-asserted-by":"crossref","award":["294777"],"award-info":[{"award-number":["294777"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Nitrogen is a chemical element that is cycled through Earth\u2019s lithosphere, hydrosphere, cryosphere and atmosphere, as well as a crucial component of the molecular machinery of life. Being an intrinsic part of the biosphere, the flow of nitrogen in a country can provide unique insights into the sustainability of a society. This study investigates how nitrogen is used in Norway between 1961 and 2020. Nitrogen inputs from atmospheric deposition, biological nitrogen fixation and from weathering, as well as from synthetic fertilizers are addressed. These sources of nitrogen are used by plants that form the basis of agriculture and forestry. Nitrogen, in the form of protein, is imported to sustain the Norwegian population and the production of animals in agriculture and fisheries. Agricultural livestock is used almost exclusively for domestic consumption, while fish captured and raised in aquaculture are the main sources of exported food. Even though petroleum and wood contain only a small proportion of nitrogen, due to the traded volume, a large amount of nitrogen contained in these goods is exported. Nitrogen is lost through sewage and manure leaching, as well as atmospheric emissions. These emissions are mostly in the form of nitrogen oxides and ammonia, which are released by burning fossil fuels and metabolizing animals, respectively.<\/jats:p>","DOI":"10.1371\/journal.pone.0313598","type":"journal-article","created":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T18:43:52Z","timestamp":1739472232000},"page":"e0313598","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Nitrogen budget for Norway analysis of Nitrogen flows from societal and natural sources (1961\u20132020)"],"prefix":"10.1371","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2957-7052","authenticated-orcid":true,"given":"Martin F.","family":"Hohmann-Marriott","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"340","published-online":{"date-parts":[[2025,2,13]]},"reference":[{"key":"pone.0313598.ref001","first-page":"e1600983","article-title":"Snowball Earth climate dynamics and Cryogenian geology-geobiology","volume":"3","author":"P. F. Hoffman","year":"2017","journal-title":"Sci. Advanc"},{"key":"pone.0313598.ref002","doi-asserted-by":"crossref","first-page":"897","DOI":"10.1126\/science.aax1192","article-title":"Archaeological assessment reveals Earth\u2019s early transformation through land use","volume":"365","author":"L. Stephens","year":"2019","journal-title":"Science"},{"key":"pone.0313598.ref003","first-page":"389","volume-title":"The natural laws of husbandry","author":"J. von Liebig","year":"1863"},{"key":"pone.0313598.ref004","first-page":"692","volume-title":"Population Encyclopedia","author":"V. Smil","year":"2003"},{"key":"pone.0313598.ref005","first-page":"9","article-title":"Nitrogen cycle and world food production","volume":"2","author":"V. Smil","year":"2011","journal-title":"World Agriculture"},{"key":"pone.0313598.ref006","doi-asserted-by":"crossref","first-page":"126","DOI":"10.1579\/0044-7447-31.2.126","article-title":"Nitrogen and food production: Proteins for human diets","volume":"31","author":"V. Smil","year":"2002a","journal-title":"Ambio"},{"key":"pone.0313598.ref007","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1111\/j.1728-4457.2002.00599.x","article-title":"Eating meat: evolution, patterns, and consequences","volume":"28","author":"V. Smil","year":"2002","journal-title":"Population Devel. R."},{"key":"pone.0313598.ref008","author":"V. Smil","year":"2013"},{"key":"pone.0313598.ref009","volume-title":"Land, Shops and Kitchens: Technology and the Food Chain in Twentieth-century Europe.","author":"V. Smil","year":"2005"},{"key":"pone.0313598.ref010","doi-asserted-by":"crossref","first-page":"2579","DOI":"10.1038\/srep02579","article-title":"The role of industrial nitrogen in the global nitrogen biogeochemical cycle","volume":"3","author":"B. Gu","year":"2013","journal-title":"Sci. Rep"},{"key":"pone.0313598.ref011","unstructured":"UN: Guidance document on National Nitrogen Budgets, Detailed Annexes to ECE\/EB.AIR\/119 (updated 2021_03_02), United Nations Economic Commission for Europe, https:\/\/www.clrtap-tfrn.org\/sites\/clrtap-tfrn.org\/files\/documents\/EPNB_new\/EPNB_annex_20210302_public.pdf, 2021."},{"key":"pone.0313598.ref012","unstructured":"Geupel, Jering, Frey, Gohlisch, Lambrecht, Jaschinski, Koppe, M\u00f6nch, Galander: Hintergrundpapier zu einer multimedialen Stickstoffemissionsminderungsstrategie Umweltbundesamt, Germany, (https:\/\/www.umweltbundesamt.de\/sites\/default\/files\/medien\/publikation\/long\/3982.pdf), 2009."},{"key":"pone.0313598.ref013","first-page":"9","article-title":"National nitrogen budget for Germany","volume":"3","author":"U. H\u00e4u\u00dfermann","year":"2021","journal-title":"Environ. Res. Com."},{"key":"pone.0313598.ref014","volume-title":"Stoffflussanalyse f\u00fcr das Jahr 2005","author":"J. Heldstab","year":"2010"},{"key":"pone.0313598.ref015","doi-asserted-by":"crossref","first-page":"2052","DOI":"10.1073\/pnas.1221638110","article-title":"Centennial-scale analysis of the creation and fate of reactive nitrogen in China (1910\u20132010),","volume":"110","author":"S. Cui","year":"2013","journal-title":"Proc. Nat. Acad. Sci. (USA)"},{"key":"pone.0313598.ref016","first-page":"286","article-title":"Uncertainty of nitrogen budget in China","author":"X. Zhang","year":"2021","journal-title":"Environment. Pol"},{"key":"pone.0313598.ref017","doi-asserted-by":"crossref","first-page":"115012","DOI":"10.1088\/1748-9326\/9\/11\/115012","article-title":"A nitrogen budget for Denmark; developments between 1990 and 2010, and prospects for the future","volume":"9","author":"N. Hutchings","year":"2014","journal-title":"Environ. Res. Let"},{"key":"pone.0313598.ref018","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1007\/s10533-016-0234-4","article-title":"The UK\u2019s total nitrogen budget from 1990 to 2020: a transition from source to sink?","volume":"129","author":"F. Worrall","year":"2016","journal-title":"Biogeochem"},{"key":"pone.0313598.ref019","article-title":"A Comprehensive approach to nitrogen in the UK","author":"W. K. Hicks","journal-title":"Word Wildlife Fund UK"},{"key":"pone.0313598.ref020","first-page":"2019","volume-title":"Swedish National Nitrogen Budget\u2013Hydrosphere\u2013(2020),","author":"IVL: Nitrogen budget\u2014Agriculture Sweden","year":"2019"},{"key":"pone.0313598.ref021","doi-asserted-by":"crossref","DOI":"10.6027\/TN2017-547","article-title":"Nordic nitrogen and agriculture: Policy, measures and recommendations to reduce environmental impact","volume":"547","author":"S. Hellsten","year":"2017","journal-title":"TemaNord"},{"key":"pone.0313598.ref022","unstructured":"Eurostat Gross Nutrient. Gross nutrient balance (aei_pr_gnb) Eurostat\u2013European Commission."},{"key":"pone.0313598.ref023","first-page":"134","article-title":"The nitrogen cost of food production: Norwegian society","volume":"26","author":"M. A. Bleken","journal-title":"Ambio"},{"key":"pone.0313598.ref024","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1579\/0044-7447(2008)37[9:CCIOAN]2.0.CO;2","article-title":"Climate change impact on atmospheric nitrogen deposition in northwestern Europe: a model study","volume":"37","author":"L. Hole","year":"2008","journal-title":"Ambio"},{"key":"pone.0313598.ref025","doi-asserted-by":"crossref","first-page":"1459","DOI":"10.1139\/cjfr-2015-0467","article-title":"Carbon and nitrogen stocks in Norwegian forest soils\u2014the importance of soil formation, climate, and vegetation type for organic matter accumulation","volume":"46","author":"L. T. Strand","year":"2016","journal-title":"Canad. J. Forest Res."},{"key":"pone.0313598.ref026","article-title":"Nitrogen losses from two contrasting agricultural catchments in Norway,","author":"X. Chen","year":"2019","journal-title":"Royal Soc. Open Sci"},{"key":"pone.0313598.ref027","unstructured":"SK Kartverket, Arealstatistikk for Norge, Statens Kartverk, Norway."},{"key":"pone.0313598.ref028","unstructured":"FAO Land Use. FAOStat\u2013Land Use (RL) Food and Agriculture Organization\u2013United Nations"},{"key":"pone.0313598.ref029","doi-asserted-by":"crossref","first-page":"131","DOI":"10.1080\/00291951.2018.1468356","article-title":"Land cover in Norway based on an area frame survey of vegetation types,","volume":"72","author":"A. Bryn","journal-title":"Norsk Geografic Tidsskrift\u2014Norwegian J. Geography"},{"key":"pone.0313598.ref030","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.envsoft.2014.07.001","article-title":"Comparison of variance estimation methods for use with two-dimensional systematic sampling of land use\/land cover data","volume":"61","author":"L. Aune-Lundberg","year":"2014","journal-title":"Environ. Model. Software"},{"key":"pone.0313598.ref031","doi-asserted-by":"crossref","first-page":"933","DOI":"10.1641\/0006-3568(2001)051[0933:TEOTWA]2.0.CO;2","article-title":"Terrestrial ecoregions of the world: a new map of life on Earth","volume":"51","author":"D, M Olson","year":"2001","journal-title":"Biosci"},{"key":"pone.0313598.ref032","unstructured":"FAO_CroplandNutrientBudget. FAOStat\u2013Cropland Nutrient Budget\u2013Cropland Nitrogen (ESB) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref033","doi-asserted-by":"crossref","DOI":"10.3389\/ffgc.2021.678480","article-title":"Effects of climate and atmospheric nitrogen deposition on early to mid-term stage litter decomposition across biomes","volume":"4","author":"T. Kwon","year":"2021","journal-title":"Front. Forest. Global Change"},{"key":"pone.0313598.ref034","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1126\/science.aan4399","article-title":"Convergent evidence for widespread rock nitrogen sources in Earth\u2019s surface environment","volume":"360","author":"B. Z. Houlton","year":"2018","journal-title":"Science"},{"issue":"2","key":"pone.0313598.ref035","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1029\/1999GB900014","article-title":"Global patterns of terrestrial biological nitrogen (N2) fixation in natural ecosystems","volume":"13","author":"C. C. Cleveland","year":"1999","journal-title":"Global Biogeochem. Cycles"},{"key":"pone.0313598.ref036","doi-asserted-by":"crossref","first-page":"3643","DOI":"10.5194\/bg-17-3643-2020","article-title":"Modeling biological nitrogen fixation in global natural terrestrial ecosystems","volume":"17","author":"Y. Tong","year":"2020","journal-title":"Biogeosci"},{"key":"pone.0313598.ref037","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1093\/biosci\/bix014","article-title":"An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm,","volume":"67","author":"E. Dinerstein","year":"2017","journal-title":"Biosci"},{"key":"pone.0313598.ref038","doi-asserted-by":"crossref","first-page":"180214","DOI":"10.1038\/sdata.2018.214","article-title":"Present and future K\u00f6ppen-Geiger climate classification maps at 1-km resolution","volume":"5","author":"H. Beck","year":"2018","journal-title":"Sci. Data"},{"key":"pone.0313598.ref039","first-page":"200","article-title":"Emission of Gaseous Nitrogen Oxides in Soils of Boreal Forests (Review),","volume":"51","author":"S. M. Razgulin","year":"2024","journal-title":"Ecology"},{"key":"pone.0313598.ref040","unstructured":"FAO Fertilizers By Nutrient. FAOStat\u2013Fertilizers By Nutrient (RFN) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref041","unstructured":"EIA Energy\/ International Energy Statistics. Energy Information Administration\u2014EIA, Department of Energy\u2014DOE, USA."},{"key":"pone.0313598.ref042","doi-asserted-by":"crossref","first-page":"1259","DOI":"10.1016\/S0082-0784(06)80148-7","article-title":"Functional forms of nitrogen in coals and the release of coal nitrogen as NOx precursors (HCN and NH3),","volume":"24","author":"P. F. Nelson","year":"1992","journal-title":"Symposium (International) on Combustion"},{"key":"pone.0313598.ref043","first-page":"1973","volume-title":"Chemical Engineers\u2019 Handbook 5th edition","author":"W. Reid"},{"key":"pone.0313598.ref044","doi-asserted-by":"crossref","first-page":"3708","DOI":"10.1021\/acs.energyfuels.6b03297","article-title":"and \u00d8ye, G.: Influence of the Crude Oil and Water Compositions on the Quality of Synthetic Produced Water","volume":"314","author":"M. Dudek","year":"2017","journal-title":"Energy Fuels"},{"key":"pone.0313598.ref045","unstructured":"ODN: Conversion Table, Oljedirektoratet, Norway, https:\/\/www.npd.no\/en\/about-us\/use-of-content\/conversion-table\/, accessed 2022_09_17."},{"key":"pone.0313598.ref046","unstructured":"FAO Forestry. FAOStat\u2013Forestry Production and Trade (FO) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref047","unstructured":"SSB Forestry\u2014Table 08979: Commercial roundwood removals (1 000 m3), by contents, wood-group and year, Statistisk sentralbyr\u00e5 \/ Statistics Norway."},{"key":"pone.0313598.ref048","doi-asserted-by":"crossref","first-page":"1555","DOI":"10.1139\/b66-168","article-title":"Role of nitrogen in wood deterioration: Amounts and distribution of nitrogen in tree stems","volume":"44","author":"W. Merrill","year":"1966","journal-title":"Canadian J. Bot."},{"key":"pone.0313598.ref049","volume-title":"Geneva Timber and Forest Discussion Paper 49","author":"UNECE","year":"2010"},{"key":"pone.0313598.ref050","author":"FAO"},{"key":"pone.0313598.ref051","doi-asserted-by":"crossref","first-page":"111","DOI":"10.2166\/wst.2004.0175","article-title":"Nutrient minimisation in the pulp and paper industry: an overview","volume":"50","author":"A. H. Slade","year":"2004","journal-title":"Water Sci. Tech."},{"key":"pone.0313598.ref052","unstructured":"FAO Fish Capture. Fisheries\u2014Global capture production (GCP) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref053","unstructured":"FAO Fish Aquaculture. Fisheries\u2014Global aquaculture production\u2013(GAP) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref054","doi-asserted-by":"crossref","first-page":"101316","DOI":"10.1016\/j.aqrep.2022.101316","article-title":"Utilization of feed resources in the production of Atlantic salmon (Salmo salar) in Norway: An update for 2020","volume":"26","author":"T. S. Aas","year":"2022","journal-title":"Aquacul. Rep"},{"key":"pone.0313598.ref055","doi-asserted-by":"crossref","first-page":"101317","DOI":"10.1016\/j.aqrep.2022.101317","article-title":"Utilization of feed resources in the production of rainbow trout (Oncorhynchus mykiss) in Norway in 2020","volume":"26","author":"T. S. Aas","year":"2022","journal-title":"Aquacul. Rep"},{"key":"pone.0313598.ref056","unstructured":"FAO Non-Food. FAOStat\u2013Commodity Balances (CB\/CBH) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref057","first-page":"7432","article-title":"Oil Press-Cakes and Meals Valorization through Circular Economy Approaches","volume":"10","author":"P. Ancuta","year":"2020","journal-title":"A Review, Appl. Sci,"},{"key":"pone.0313598.ref058","unstructured":"SSB Fodder\u2014Table 05771: Yield of agricultural crops, by different crops (tonnes) (closed series) 2000\u20132020, Statistisk sentralbyr\u00e5 \/ Statistics Norway."},{"key":"pone.0313598.ref059","unstructured":"FAO Food. FAOStat\u2013Food Balances (FB\\FBH) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref060","unstructured":"Feedipedia: Feedipedia: Animal Feed Resources Information System, https:\/\/feedipedia.org, accessed between 2022_07_21\u20132022_08_16."},{"key":"pone.0313598.ref061","unstructured":"FAO Feed. FAOStat\u2013Crops and livestock products (TCL) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref062","volume-title":"Guidelines on methods for estimating livestock production and productivity","author":"FAO","year":"2018"},{"key":"pone.0313598.ref063","unstructured":"Forrest, J. C., Aberle, E. D., Hedrick, H. B., Judge, M. D., and Merkel, R. A.: Principles of Meat Science, W.H. Freeman and Company."},{"key":"pone.0313598.ref064","unstructured":"FAO Livestock and Manure. FAOStat\u2013Livestock Manure (EMN) Food and Agriculture Organization\u2013United Nations."},{"key":"pone.0313598.ref065","unstructured":"FAO: Dataset Information: Livestock Manure https:\/\/fenixservices.fao.org\/faostat\/static\/documents\/EMN\/EMN_e.pdf Food and Agriculture Organization\u2013United Nations, accessed 2022_11_11."},{"key":"pone.0313598.ref066","unstructured":"USDA Food\u2014FoodData Central\u2014United States Department of Agriculture."},{"key":"pone.0313598.ref067","volume-title":"Food energy\u2014methods of analysis and conversion factors","author":"FAO","year":"2003"},{"key":"pone.0313598.ref068","author":"D. B. Jones","year":"1931"},{"key":"pone.0313598.ref069","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1080\/10408390701279749","article-title":"Converting Nitrogen into Protein\u2014Beyond 6.25 and Jones\u2019 Factors","volume":"48","author":"F. Mariotti","year":"2008","journal-title":"Crit. Rev. Food Sci. Nutrition"},{"key":"pone.0313598.ref070","author":"D. Tom\u00e9","year":"2019"},{"key":"pone.0313598.ref071","unstructured":"SSB_Immigration and Emigration\u2014Table 05869: Immigration and emigration 1958\u20132021, Statistics Norway \/ Statistisk sentralbyr\u00e5."},{"key":"pone.0313598.ref072","article-title":"Human Ammonia Emission Rates under Various Indoor Environmental Conditions","author":"M. Li","year":"2020","journal-title":"Environ. Sci. Technol"},{"key":"pone.0313598.ref073","unstructured":"SSB Sewage- Table 05280: Totale utslipp av fosfor og nitrogen fra avl\u00f8pssektoren, etter \u00e5r, statistikkvariabel og utslipp, Statistisk sentralbyr\u00e5 \/ Statistics Norway."},{"key":"pone.0313598.ref074","unstructured":"SSB Sewage and Sludge\u2014Table 11788: Kommunalt avl\u00f8psslam (K) 2015\u20132021 Statistics Norway \/ Statistisk sentralbyr\u00e5."},{"key":"pone.0313598.ref075","unstructured":"Berge, G., and S\u00e6ther, M. S.: Kommunale avl\u00f8p 2018, Statistics Norway \/ Statistisk sentralbyr\u00e5, Norway."},{"key":"pone.0313598.ref076","unstructured":"SSB Waste\u2014Table 10514: Waste account for Norway, by source of origin and material (1 000 tonnes) 2012\u20132021, Statistics Norway \/ Statistisk sentralbyr\u00e5."},{"key":"pone.0313598.ref077","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1016\/j.resconrec.2016.03.010","article-title":"Edible food waste from Norwegian households\u2014Detailed food waste composition analysis among households in two different regions in Norway","volume":"109","author":"O. J. Hanssen","year":"2016","journal-title":"Resources Conserv. Recycl."},{"key":"pone.0313598.ref078","volume-title":"EEA Report No 04\/2020","author":"EEA","year":"2020"},{"key":"pone.0313598.ref079","unstructured":"SSB NOx Ammonia Emission\u2014Table 08941: Forsurende gasser, ozonforl\u00f8pere m.fl., etter komponent, \u00e5r, statistikkvariabel og kilde (aktivitet), Statistisk sentralbyr\u00e5 \/ Statistics Norway."},{"key":"pone.0313598.ref080","doi-asserted-by":"crossref","first-page":"52","DOI":"10.1080\/10473289.1998.10463664","article-title":"Quantifying NOx for Industrial Combustion Processes,","volume":"48","author":"C. E. Baukal","year":"1998","journal-title":"J. Air Waste Manag. Assoc"},{"key":"pone.0313598.ref081","unstructured":"EPA: Nitrogen Oxide Control for Stationary Combustion Sources (EPA\/625\/5-86\/020). U.S. Environmental Protection Agency. U.S. Government Printing Office: Washington, DC, 1986."},{"key":"pone.0313598.ref082","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1080\/02723646.2015.1016384","article-title":"Overlap of global K\u00f6ppen\u2013Geiger climates, biomes, and soil orders","volume":"36","author":"R. V. Rohli","year":"2015","journal-title":"Physic. Geogr"},{"key":"pone.0313598.ref083","article-title":"Deposition of sulfur and nitrogen n Norway 2017\u20132021, Norwegian Meterological Institute","author":"L. R. Blake","year":"2023","journal-title":"NILU Met Report No. 03\/2023"},{"key":"pone.0313598.ref084","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1039\/tf9060200098","article-title":"On the oxidation of atmospheric nitrogen in electric arcs","volume":"2","author":"K. Birkeland","year":"1906","journal-title":"Transactions of the Faraday Society"},{"key":"pone.0313598.ref085","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1002\/zaac.19050440122","article-title":"\u00dcber die Bildung von Ammoniak den Elementen,","volume":"44","author":"F. Haber","year":"1905","journal-title":"Z. Anorg. Chem"},{"key":"pone.0313598.ref086","volume-title":"Liquefied Natural Gas: Understanding the Basic Facts","author":"DOE","year":"2013"},{"key":"pone.0313598.ref087","first-page":"85","volume-title":"Chemistry in its applications to agriculture and physiology","author":"J von Liebig","year":"1840"},{"key":"pone.0313598.ref088","first-page":"2","article-title":"Nitrogen in the effluent of the pulp and paper industry,","volume":"35","author":"R. Jaervinen","year":"1997","journal-title":"Water Sci. Tech"},{"key":"pone.0313598.ref089","unstructured":"NDF Fish Products, N\u00f8kkeltall fra norsk havbruksn\u00e6rin (2018), Key figures from Norwegian Aquaculture Industry (2018), Norwegian Directorate of Fisheries \/ Fiskedirectoratet Norge."},{"key":"pone.0313598.ref090","volume-title":"Fisheries and Aquaculture in Norway, Review of Fisheries Country Notes","author":"OECD","year":"2021"},{"key":"pone.0313598.ref091","doi-asserted-by":"crossref","first-page":"365","DOI":"10.1016\/j.aquaculture.2015.06.023","article-title":"Utilisation of feed resources in production of Atlantic salmon (Salmo salar) in Norway","volume":"448","author":"T. Ytrest\u00f8yl","year":"2015","journal-title":"Aquaculture"},{"key":"pone.0313598.ref092","first-page":"2025","article-title":"Bruk av gj\u00f8dselressurser i jordbruket 2018, Statistisk sentralbyr\u00e5 \u2022 Statistics NorwayLuo, Z","volume":"52","author":"S. O. Kolle","year":"2018","journal-title":"From production to consumption: a coupled human-environmental nitrogen flow analysis in China, Environ. Sci. Tech"},{"key":"pone.0313598.ref093","unstructured":"\u00d8gaard, A. F., Sveistrup, T., and Haraldsen, TK.: NIBIO Rapport 7, 151, Norsk Institutt for Bio\u00f8konomi\u2014NIBIO, Norway, 2021."},{"key":"pone.0313598.ref094","doi-asserted-by":"crossref","first-page":"6506","DOI":"10.1073\/pnas.1711842115","article-title":"The biomass distribution on Earth","volume":"115","author":"YM Bar","year":"2018","journal-title":"Proc. Nat. Acad. Sci (USA),"},{"key":"pone.0313598.ref095","doi-asserted-by":"crossref","first-page":"442","DOI":"10.1038\/s41586-020-3010-5","article-title":"Global human-made mass exceeds all living biomass","volume":"588","author":"E. Elhacham","year":"2020","journal-title":"Nature"},{"key":"pone.0313598.ref096","doi-asserted-by":"crossref","first-page":"13596","DOI":"10.1073\/pnas.1922686117","article-title":"Vertebrates on the brink as indicators of biological annihilation and the sixth mass extinction","volume":"17","author":"G. Ceballos","year":"2020","journal-title":"Proc. Nat. Acad. Sci. (USA)"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0313598","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,2,13]],"date-time":"2025-02-13T18:44:29Z","timestamp":1739472269000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0313598"}},"subtitle":[],"editor":[{"given":"Tzen-Yuh","family":"Chiang","sequence":"first","affiliation":[],"role":[{"role":"editor","vocabulary":"crossref"}]}],"short-title":[],"issued":{"date-parts":[[2025,2,13]]},"references-count":96,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,2,13]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0313598","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,13]]}}}