Enhancing nitrogen use efficiency to assure sustainable intensification of crop production, while minimizing N-environmental threats, is a major challenge. These drive important developments of N-fertilization approaches and enhanced efficiency N-fertilizers (EENFs). The complexity of N-dynamics under different soils, environmental conditions, and application modes requires improvement of decision-making tools. Meta-analyses demonstrate the contribution of EENFs to sustainable intensification. Yet, improvements based on local field specific information, and particularly with new N-fertilization approaches, are needed. This project focuses on an upgraded laboratory designed steady state incubation system connected to a Long-Path gas cell mounted on an FTIR spectrometer, allowing fast determination of NH₃ and N₂O emissions concomitant with mineral N-dynamics in soils under different N-fertilization approaches. The system was tested with four representative soils, fertilized with surface applied urea or urea amended with urease inhibitors (UI). Different soil water saturation (WS) levels and urea application rates were tested over 14 days of incubation·NH₃ losses (%N-applied) in the steady state system were 2 to 7 times higher than in the previously designed non-steady state system. Highest losses were observed when urea was applied to lighter soils with pH above 7.5 (~13% to 46%), especially under low (30%) water saturation (WS). Substituting to UI reduced the accumulated NH₃ losses (14 days) by 55 to 92%. Highest N₂O losses were obtained with the lighter soils (1.2% to 1.7%) at 50% WS and lowest urea application rate. UI assisted in reducing N₂O losses in some of the tested soils, showing different dependencies on WS and urea concentration. This variety demonstrates the complexity of the N-processes involved under different soils and conditions, and was also expressed in the mineral-N concentrations. This simple experimental design has the potential to improve our insights and help evaluate EENFs sustainability.

提高氮的使用效率以确保作物生产的可持续集约化，同时最大限度地减少氮环境威胁，是一项重大挑战。这些推动了施氮方法和提高效率的氮肥 (EENF) 的重要发展。不同土壤、环境条件和应用模式下氮动力学的复杂性需要改进决策工具。荟萃分析证明了 EENF 对可持续集约化的贡献。然而，需要根据当地田间特定信息进行改进，尤其是使用新的施氮方法。该项目的重点是升级实验室设计的稳态孵化系统，该系统连接到安装在 FTIR 光谱仪上的长路径气室，可快速测定 NH ₃和 N在不同施氮方法下，土壤中伴随矿物氮动力学的₂ O 排放。该系统用四种有代表性的土壤进行了测试，这些土壤用表面施用的尿素或用尿素酶抑制剂 (UI) 修正的尿素施肥。在 14 天的孵化过程中测试了不同的土壤水饱和度 (WS) 水平和尿素施用率·稳态系统中的NH ₃损失（施氮百分比）比之前设计的非稳态系统高 2 至 7 倍. 当尿素施用于 pH 值高于 7.5（~13% 至 46%）的较轻土壤时，观察到的损失最高，尤其是在低（30%）水饱和度 (WS) 下。替换为 UI 将累积的 NH ₃损失（14 天）减少了 55% 至 92%。最高 N ₂在 50% WS 和最低尿素施用率下，较轻的土壤（1.2% 至 1.7%）获得了 O 损失。UI 有助于减少一些测试土壤中的N ₂ O 损失，显示出对 WS 和尿素浓度的不同依赖性。这种多样性表明了在不同土壤和条件下所涉及的氮过程的复杂性，并且还表现在矿物氮浓度上。这个简单的实验设计有可能提高我们的洞察力并帮助评估 EENFs 的可持续性。