In this study, we assessed the potential of enhanced-efficiency nitrogen (EEN) fertilizers for mitigating nitrous oxide (N₂O) emissions and compared it with that of common urea. N₂O-N emission factor (EF-N₂O, % applied N emitted as N₂O-N) and yield-scaled N₂O-N emissions (N₂O-N emitted per yield unit) for wheat, bean and black oat were determined in southern Brazil. Four EEN fertilizers were evaluated for comparison with common urea, namely: urea with urease inhibitor (Ur-NBPT), urea coated with an inorganic polymer (Ur-pol), ammonium nitrate (Nitrate), urea treated with copper and boron polymer (Ur-CuB) and control treatment with no N fertilizer. The first two EEN fertilizers were applied to all crops, the third only to wheat and the fourth to bean and black oat. None of the EEN fertilizers reduced N₂O-N emissions or increased crop yields relative to common urea in winter wheat or black oat. By contrast, Ur-pol and Ur-CuB reduced N₂O-N emissions in summer bean by 41 and 39%, respectively, and Ur-pol increased grain yield by 40%, relative to common urea. Although the Ur-NBPT proved efficient in decreasing soil N₂O-N fluxes at an early stage, no effect was observed in the mid or long term (> 12 days) and, thus, the effect on total N₂O-N emissions was not significant. Our findings testify to the potential of some EEN fertilizers for decreasing N₂O-N yield-scaled emissions in summer crop seasons relative to common urea, the effect having no considerable impact under the mild winter conditions. EF-N₂O-N averaged 0.87 ± 0.40% across crop seasons (ranging from 0.44 to 1.45%).

在本研究中，我们评估了增效氮 (EEN) 肥料在减少一氧化二氮 (N ₂ O) 排放方面的潜力，并将其与普通尿素进行了比较。N ₂ O-N 排放因子（EF-N ₂ O，应用的 N 以 N ₂ O-N 形式排放的百分比）和产量规模的 N ₂ O-N 排放（N ₂在巴西南部测定了小麦、豆类和黑燕麦的每产量单位排放量。评估了四种 EEN 肥料以与普通尿素进行比较，即：尿素酶抑制剂 (Ur-NBPT)、无机聚合物涂层尿素 (Ur-pol)、硝酸铵 (Nitrate)、铜硼聚合物处理尿素 (Ur -CuB) 和没有施氮肥的对照处理。前两种 EEN 肥料施用于所有作物，第三种仅用于小麦，第四种用于豆类和黑燕麦。与冬小麦或黑燕麦中的普通尿素相比，没有一种 EEN 肥料能减少 N ₂ O-N 排放或增加作物产量。相比之下，Ur-pol 和 Ur-CuB 减少了 N ₂相对于普通尿素，夏豆中的 ON 排放量分别增加了 41% 和 39%，Ur-pol 将谷物产量提高了 40%。尽管 Ur-NBPT 在早期证明能有效降低土壤 N ₂ O-N 通量，但在中长期（> 12 天）中没有观察到效果，因此对 N ₂ O-N总排放量的影响不显着。我们的研究结果证明，相对于普通尿素，一些 EEN 肥料在减少夏季作物季节N ₂ O-N 产量规模排放方面的潜力，这种效果在温和的冬季条件下没有显着影响。EF-N ₂ O-N 在整个作物季节平均为 0.87 ± 0.40%（从 0.44 到 1.45%）。