Proceedings of the XXII International Nitrogen Workshop

XXII N Workshop 2024Book of abstracts Proceedings of the XXIIInternational NitrogenWorkshopResolving the Global Nitrogen Dilemma-Opportunities and Challenges17th–21thJune 2024Aarhus 2024 Forword More than half ofthe world’s population is nourished by crops grown with nitrogen (N)fertilizers. As global food demand continues to grow in the coming decades, the demand forN inputs and for agricultural land are expected to increase substantially. Unfortunately, toomuch N in the Earth’s soils poses multiple severe environmental and health problems thathave yet to be solved. Inefficient N use contributes to global warming, ozone depletion,eutrophication, reduced biodiversity, and aerosols that contribute to air pollution and healthproblems. From a socio-economic perspective, N losses reduce farmer's profits and affectfood security. We are facing a global N dilemma of an unprecedented magnitude: how dowe reconcile the need for sufficient N inputs to ensure crop productivity and human nutritionwith the need for reducing N losses to sustain a viable environment and healthy ecosystems?Improving N use efficiency, reducing N losses along the food and feed processing chain, andincreasing N recycling are key challenges to address this dilemma. There is a large andgrowing body of knowledge and technological capacity to improve crop N uptake, manageN losses along the food chain, and recycle N from waste streams, but implementation of thisknowledge requires cooperation and co-creation among actors and stakeholders includingresearchers, farmers, advisors, industry, NGOs, and policymakers, and raising awareness that Nuse in agriculture is a double-edged sword. The N workshop aims to raise awareness of the Nrelated challenges and to share the newest information on innovations and progress on Nimpact research to develop concrete strategies to dramatically improve N managementworldwide. To do so, we not only need to further improve the technological andmanagement options that increase N use efficiency, but even more importantly, we mustunderstand the socio-cultural and economic incentives needed to encourage farmers toadopt such options. Since 1982, researchers from different parts of the world have regularly gathered at the Nworkshop in different locations to try to put all the parts of the N puzzle together. The XXIIedition of the International N Workshop, hosted by Aarhus University,contributed to solvingthis challenge by welcoming exciting presentations of more than 350 participants from 36different countries divided into six regular and four special sessions, together with sevenkeynotes by outstanding international scientists. Over 5 days in Aarhus, the participants covered a wide range of topics including fieldmeasurements, farm to global N budgets, and food system perspectives, which aresummarized in this book of abstracts. We hope that this workshop is a turning point in the Ndilemma and makes a decisive contribution to the transformation of agriculture and the agri-food system. We would like to thank all the people who made the XXII International NWorkshop possible, including our local staff and helpers, the session leads, members of thescientific committee, the conference sponsors, and all the participants for their contributions. Diego Abalos, Klaus Butterbach-Bahl, Hanne L. Kristensen, Jørgen E. Olesen OrganizingCommittee Jørgen Eivind OlesenDepartment of AgroecologyAarhusUniversity Diego AbalosDepartment of AgroecologyAarhus University Friederike Malisch-JohnigkDepartment of AgroecologyAarhus University Hanne Lakkenborg KristensenDepartment of Food ScienceAarhus University Birgit S. LangvadDepartment of AgroecologyAarhus University Klaus Butterbach-BahlCenter for Landscape Research inSustainable Agricultural FuturesAarhus University Session Leads How to increase nitrogen use efficiencyJørgen Eriksen(Aarhus University, Denmark)Alberto Sanz-Cobeña(Technical University of Madrid, Spain)David Kanter(New York University, USA) Reducing nitrogen lossesSøren O. Petersen(Aarhus University, Denmark)Iris Vogeler(Aarhus University, Denmark)Mari Luz Cayuela(Consejo Superior de Investigaciones Científicas, Spain) Nitrogen recyclingUffe Jørgensen(Aarhus University, Denmark)Peter Sørensen(Aarhus University, Denmark)Lorie Hamelin(National Research Institute for Agriculture, Food and Environment (INRAE),France) Incentives for good nitrogen managementBrian Jacobsen(University of Copenhagen, Denmark)Tommy Dalgaard(Aarhus University, Denmark)Wilfried Winiwarter(International Institut for Applied Systems Analysis (IIASA), Austria) Food systemsLuis Lassaletta(Technical University of Madrid, Spain)José Mogollón(Leiden University, NL)Ute Skiba(Centre for Ecology&Hydrology, UK) Livestock in agricultural systems from a nitrogen perspectiveMariana C. Rufino(Technical University Munich, GER)Christian Friis Børsting(Aarhus University, DK)Johanna Pedersen(Aarhus University, DK) Special session: Nitrogen in organic farming Hann