Dual film-controlled model urea improves summer maize yields, N fertilizer use efficiency and reduces greenhouse gas emissions

Abstract

Controlled-release fertilizers are recognized for improving nitrogen efficiency, but they are significantly affected by environmental factors and often leading to suboptimal results. Nitrogen fertilizer synergists, due to their water solubility, exhibit limited persistence in the soil and cannot achieve the desired effect. Therefore, we incorporated nitrogen fertilizer synergists into the film of controlled-release fertilizer. Nitrogen fertilizer synergists were encapsulated within the film of the controlled-release fertilizer to achieved “dual film-controlled model”, which improved the performance of the controlled release fertilizer. A field experiment was conducted with five treatments: no N fertilizer (N0), controlled-release fertilizer (C210), controlled-release fertilizer combined with urease inhibitor (C210N), controlled-release fertilizer combined with nitrification inhibitor (C210D), controlled-release fertilizer combined with nitrification inhibitor and urease inhibitor (C210DN). Maize yield and economics, nitrogen use efficiency, gas emissions, global warming potential and apparent nitrogen losses were assessed. The results indicated that the application of this model regulates soil microbial community structure and functionality, thereby influencing soil nitrogen cycling processes and reduced global warming potential (GWP) and greenhouse gas intensity (GHGI). Additionally, C210DN increased NH₄⁺-N content in the 0–20 cm soil layer at the sixth leaf stage and the tasseling stage, while significantly decreasing NO₃^--N content. The dual film-controlled model improved nitrogen use efficiency by 7.9 %–17.7 %. Overall, the dual film-controlled urea model enhanced summer maize yield and nitrogen fertilizer use efficiency while mitigating environmental pollution and emissions.