<b>Globally scalable management solutions to mitigate the agricultural reactive nitrogen crisis</b>

The reactive nitrogen (Nr) crisis poses a pressing global challenge and demands agroecosystem management practices that balance crop productivity and Nr losses to the environment. Here, we quantify the effects of 14 common management practices on Nr losses and crop productivity by conducting a second-order meta-analysis based on 6,382 unique primary studies comprising 20,167 paired observations. We identify four globally scalable ‘win-win’ practices: enhanced-efficiency fertilizers, reduced N input, optimized fertilization, and biochar amendment. These practices have the potential to reduce emissions of N₂O, NO, and NH₃ by up to 35%, 35% and 40%, respectively, reduce Nr leaching or runoff by up to 27%, while simultaneously increasing nitrogen use efficiency by 71%, N uptake by 21%, and yield by up to 15%. Using environmental and socioeconomic predictors, we developed global suitability maps that revealed distinct regional patterns for each management practice, with the highest suitability concentrated in major cropland regions of East Asia, North America, and Europe. Our findings provide an evidence-based global synthesis of ‘win-win’ nitrogen management practices and their large-scale applicability, supporting global actions capable to deal with the agricultural reactive nitrogen crisis while sustaining food and economic security.All data and analysis scripts required to reproduce the main figures are available here.All results of the second-order meta-analysis models are available in the SI Appendix.Interactive versions of Fig. 1a and Fig. 3a are also available at the following link.https://shengwenxu.shinyapps.io/Figure1a/https://shengwenxu.shinyapps.io/Figure3a/<br> Further inquiries can be directed to [email protected]<br>