BACKGROUNDScientific fertilization plays a crucial role in addressing food security and mitigating environmental costs. We conducted a two-season field experiment in northwest China and synthesized 151 national studies to quantitatively assess the potentials of N rate, source (controlled-release urea, nitrification inhibitors, urease inhibitors, and manure) and deep placement to simultaneously reduce ammonia (NH3) and nitrous oxide (N2O) emissions while maintaining yields.RESULTSField results showed that reducing N rate from 300 to 200 kg N ha-1 resulted in a marginal yield penalty (5.3%) but decreased N2O by 28.2% and NH3 by 17.3%. Literature synthesis identified 180 kg ha-1 as the optimal N rate for 95% yield potential. Deep placement, compared to surface broadcasting, enhanced yield by 2.6% and reduced N2O by 15.3% in field trials, with meta-analysis showing substantial suppression of NH3 (80.5%) and N2O (12.5%). Manure substitution exhibited limited benefits for yield enhancement and N2O mitigation but demonstrated specific efficacy in medium- and coarse-textured soils with low soil organic carbon. Urea plus controlled-release urea performed best from meta-analysis yet its benefit diminished under high rainfall. Urea-nitrification inhibitor blends led to 5.9% higher NH3 and urea-urease inhibitors exerted limited mitigation efficacy on N2O production from field data, with meta-results confirming the risk of urease inhibitors in stimulating NH3. Dual inhibitors worked synergistically to sustain yields and alleviate N losses, especially in alkaline and coarse soils.CONCLUSIONThe combination of using controlled-release fertilizer plus traditional urea mixed with dual inhibitors and deep placement would be an enhanced approach across Chinese maize croplands under all conditions. (c) 2025 Society of Chemical Industry.