Two field experiments were conducted to compare the effectiveness and longevity of urease inhibitor (UI), N-(2-Nitrophenyl) phosphoric triamide (2-NPT) with commonly used UI N-(n-butyl) thiophosphoric triamide (nBTPT) in reducing ammonia (NH₃) emissions from cattle urine applied to pasture soil at different periods during summer and autumn. Higher proportion of applied urine N (15–24%) was emitted as NH₃–N in the summer than in autumn (only 5%). In the summer experiment, only 2-NPT significantly reduced total NH₃ emissions (20% reduction), only when urine was applied 28 days after the inhibitor application. In autumn, both inhibitors significantly reduced emissions from urine applied either 3 h before or immediately before inhibitor application. However, the reduction was greater from urine applied immediately before inhibitor application (52–73% reduction) compared to 3 h before inhibitor application (35–41% reduction). The emissions reduction from urine applied immediately before inhibitor application was greater with 2-NPT (73% reduction) compared to nBTPT (52% reduction). Overall, 2-NPT showed a greater effectiveness and longevity at reducing NH₃ emissions compared to nBTPT. Although, the total amount of N preserved by using 2-NPT is relatively small, compared to the total N added as urine, its use can contribute to mitigating a component of a farm’s deleterious environmental emissions. There was no effect of inhibitors on pasture dry matter yield and N uptake in both experiments.

中文翻译：

---

脲酶抑制剂可减少施用至牧场土壤的牛尿中的氨气排放

进行了两个现场实验，比较了尿素酶抑制剂（UI），N-（2-硝基苯基）磷酸三酰胺（2-NPT）与常用的UI N-（n-丁基）硫代磷酸三酰胺（n BTPT）的有效性和寿命。减少夏季和秋季不同时期施用到牧场土壤的牛尿中的氨（NH ₃）排放。夏季比秋季（5％），以NH ₃ -N的形式排放的尿液中的尿素氮（15-24％）比例更高。在夏季实验中，只有2-NPT显着减少了总NH ₃排放（减少20％），仅在使用抑制剂后28天才使用尿液。在秋季，两种抑制剂均可显着减少在使用抑制剂之前或之后3小时尿液中的排放物。但是，与在使用抑制剂之前的3小时（减少35–41％）相比，在使用抑制剂之前的尿液减少量更大（减少52–73％）。与n BTPT（减少52％）相比，使用NPT时（2-NPT使用），尿素排放量的减少幅度更大（2-73 ％减少）。总体而言，与n相比，2-NPT在减少NH ₃排放方面显示出更大的有效性和更长的寿命BTPT。尽管使用2-NPT保留的N总量相对较小，但与作为尿液添加的N总量相比，使用N可以有助于减轻农场有害环境排放的一部分。在两个实验中，抑制剂对牧草干物质产量和氮吸收均无影响。