Price-based nitrogen mitigation from global croplands with uneven regional responses

Anthropogenic nitrogen (N) losses from croplands have risen alongside global food production and are a major driver of transgressed planetary boundaries. Price-based policy instruments are widely proposed to curb agricultural nitrogen pollution, yet their effectiveness and distributional consequences under market feedbacks remain insufficiently understood. Here we assess the global impacts of nitrogen pricing on cropland N losses, food security and economic outcomes. We extend the global land-use model GLOBIOM by endogenizing crop- and country-specific nitrogen balances and explicitly representing multiple N-loss pathways. Field-level mitigation technologies are incorporated, with adoption governed by marginal abatement costs, yield effects and economic affordability, allowing nitrogen taxation and subsidies to interact with production decisions, land allocation and international trade. Without additional intervention, global cropland N losses increase by 28% by 2050 relative to 2020. Nitrogen taxation reverses this trend, reducing N losses by 22% (12–29%) compared with business as usual, but at the cost of higher food insecurity. Field-level mitigation technologies provide a critical buffer, delivering additional abatement and offsetting nearly one-third of the food-security losses induced by taxation. In contrast, mitigation subsidies implemented alone yield limited net mitigation, as technology-driven reductions are partly offset by subsidy-induced cropland expansion. Combining taxation, subsidies and technologies yields the most balanced outcome, reducing global N losses by 23 Tg N by 2050 while moderating food-security impacts. Responses to nitrogen pricing vary strongly across regions. Under the combined policy scenario, South Asia, East Asia and Europe together account for about 58% of global mitigation, but through distinct pathways. Economically resilient regions mainly achieve mitigation through higher adoption of field-level technologies and declines in N-loss intensity, with mitigation shares exceeding their emission shares. Less affluent regions rely more on trade adjustments, shifting part of the mitigation burden to exporting regions through virtual N flows. These contrasts translate into marked distributional effects: technologies and subsidies offset more than half of taxation-induced farmer revenue losses in high-income regions, whereas buffering effects remain limited in some low-income regions, with mitigation costs increasingly borne by consumers and governments. Overall, price-based nitrogen mitigation can halt the long-term rise in global N pollution, but its effectiveness and equity critically depend on technology deployment and policy design and must be aligned with broader food-system transformations.