Nitrogen (N) fertilizer management in agricultural field affects soil N budget that can have significant implication in greenhouse gas emission and environmental pollution. This study investigates the effects of nitrification inhibitors Dicyandiamide (DCD) and 3,4-dimethyl pyrazole phosphate (DMPP) with urea application on soil N budget and microbial community in a subtropical pasture field. A field experiment consisting of four treatments, including control, urea, urea DCD, and urea DMPP was conducted in 2016 and 2017. Nitrous oxide emission and inorganic-N losses through leaching and runoff were quantified. In addition, soil microbial community response to the imposed treatments was characterized by analysis of phospholipid fatty acid (PLFA). The results showed that DCD and DMPP applications significantly reduced fertilizer-induced N₂O emission by over 76% and 67%, respectively. Although nitrification inhibitors’ (NIs) applications greatly reduced NO₃^– in runoff and leaching, there was no significant impact of either NI on pasture biomass yields. Comparing to the plant N uptake, N loss through N₂O emission, runoff, and leaching were small in pasture. The low N losses would indicate that NI’s potential to increase yield is small. Addition of 10 kg DCD ha⁻¹ and 1 kg DMPP ha⁻¹ reduced the negative effect induced by urea on total microbial PLFA, and benefited fungi, bacteria, and actinomycetes in short-term. Overall, the results demonstrate the positive effects of NIs on greenhouse gas reduction, water quality, and improving soil health through enhancing total microbial activity and reducing microbial environmental stress.

农业领域的氮肥管理影响土壤氮素的收支，这可能对温室气体排放和环境污染产生重大影响。这项研究调查了硝化抑制剂双氰胺（DCD）和3,4-二甲基吡唑磷酸酯（DMPP）与尿素的施用对亚热带牧草田土壤氮素和微生物群落的影响。在2016年和2017年进行了包括四种处理方法的田间试验，包括对照，尿素，尿素DCD和尿素DMPP。量化了通过淋溶和径流产生的一氧化二氮排放量和无机氮损失。另外，通过分析磷脂脂肪酸（PLFA）来表征土壤微生物群落对所施加的处理的响应。结果表明，DCD和DMPP的施用显着减少了肥料引起的氮₂ O排放分别超过76％和67％。虽然硝化抑制剂（NIS）的应用大大减少NO ₃ ^-径流和浸出，有任一NI对牧场的生物质的产率没有影响显著。与植物的氮吸收相比，牧场中通过N ₂ O排放，径流和淋溶造成的氮损失很小。低氮损失表明NI提高产量的潜力很小。添加10千克DCD ha ^-1和1千克DMPP ha ^-1减少了尿素对总微生物PLFA的负面影响，并在短期内有益于真菌，细菌和放线菌。总体而言，结果表明，NIs通过增强总微生物活性和减少微生物环境压力，对减少温室气体，改善水质和改善土壤健康具有积极作用。