Soil pH as the chief modifier for regional nitrous oxide emissions: New evidence and implications for global estimates and mitigation

Nitrous oxide (N2O) is a greenhouse gas that also plays the primary role in stratospheric ozone depletion. The use of nitrogen fertilizers is known as the major reason for atmospheric N2O increase. Empirical bottom‐up models therefore estimate agricultural N2O inventories using N loading as the sole predictor, disregarding the regional heterogeneities in soil inherent response to external N loading. Several environmental factors have been found to influence the response in soil N2O emission to N fertilization, but their interdependence and relative importance have not been addressed properly. Here, we show that soil pH is the chief factor explaining regional disparities in N2O emission, using a global meta‐analysis of 1,104 field measurements. The emission factor (EF) of N2O increases significantly (p