Salinity-induced concomitant increases in soil ammonia volatilization and nitrous oxide emission

Environmental concerns about the release of reactive nitrogen (N) from intensively fertilized farmland are growing, especially regarding gaseous N losses in the form of ammonia (NH3) and nitrous oxide (N2O). While saline soils are widely distributed and gradually expanding worldwide, the effect of soil salinity on soil NH3 and N2O emissions is poorly understood. To assess the effect of soil salinity levels on NH3 volatilization and N2O emissions, a field experiment was conducted with three soil salinity levels (S0 = non-saline, S1 = 1.0 dS m−1 and S2 = 5.0 dS m−1) and two N fertilizer types (urea and ammonium sulphate). Compared to the non-saline soil, S1 and S2 salinity levels both led to significant increases in cumulative NH3 volatilization losses by 40.0%–65.2% and 89.0%–92.2%, respectively (p