Scoping European N fluxes for sustainable N management and conservation practices

Nitrogen (N) is a vital nutrient for plant growth. However, the intensive use of N fertilizers in agriculture, whereby only 30-50% of applied N is taken up by crops, has led to significant environmental challenges. Impactful losses occur through nitrate leaching to the groundwater, leading to its contamination, and through nitrous oxide (N2O) emissions, a long-lasting greenhouse gas.Acknowledging the need for a coordinated effort among the four helixes of innovation (i.e. research, society, industry and policy) to unlock the necessary efforts for monitoring N fluxes and action towards reducing N losses and increasing N use efficiency, NitroScope has two major ambitions: a) improving scientific knowledge for pedo-climatic regions getting both simple region-specific emissions factors and model-based decision support and b) bringing the knowledge to land managers so that mitigation will happen. To achieve this, NitroScope will improve N flux monitoring through 125 sites spread over at least 10 pedo-climatic regions using improved proximal sensors for high throughput continuous nitrate quantification, remote sensing, and better methodology to adequately account for the variability of in-the-field N2O emissions. The data will be gathered in a database hosted on a cloud to facilitate reporting and will be used to determine region-specific emission factors and provide model-based decision support with reduced uncertainties. Based on this, improved N management and conservation solutions will be assessed, including variable rate N fertilization and crop residue management. NitroScope will further use transdisciplinary methodology, including developing 2 farm management add-ons, to inform and engage land managers to actively contribute to monitoring and managing N fluxes in Europe while improving agricultural yield and quality. Finally, this will result in a more precise EU N budget estimation and future scenarios to support decision-making.