Global management of saline soils to boost crop yields and halve nitrogen losses.

Global soil salinity threatens food security and accelerates environmental degradation. However, the dual impacts of salinization on crop productivity and nitrogen dynamics have not been comprehensively quantified. Here we developed a spatially explicit nitrogen budget for global saline croplands and applied a pairwise comparison framework to assess salinity-induced changes in crop yields and reactive nitrogen (Nr) losses. We find that soil salinity raises nitrogen inputs by 13%, reduces nitrogen harvest by 7% and amplifies Nr losses by 61%. Our synthesis of ten categories of salinity-management practices indicates that their adoption could reduce annual Nr losses by 59%, equivalent to 2.5 million tonnes of N, while increasing crop production and delivering net global benefits of US$24.5 ± 11.8 billion per year. The largest aggregate mitigation opportunities occur in China, Pakistan and Indonesia, while Egypt emerges as the leading hotspot for per-hectare benefits. These findings highlight saline soil management as a scalable strategy for enhancing agricultural productivity and mitigating nitrogen pollution within climate-smart agriculture frameworks.