中文摘要：

为了探索硝化抑制剂在毛竹生产中的施用技术,通过培养试验研究3,4-二甲基吡唑磷酸盐（DMPP）和双氰胺（DCD）两种硝化抑制剂对毛竹林施用尿素后土壤N2O排放、氮素转化和相关氨氧化细菌（AOB）、氨氧化古菌（AOA）群落结构和丰度的影响。试验设（1）对照（CK）、（2）单施尿素（Urea）、（3）尿素＋1%DMPP（DMPP占总N的1%,下同）;（4）尿素＋1.5%DMPP;（5）尿素＋10%DCD;（6）尿素＋15%DCD等6个处理,测定N2O的排放动态以及气体排放转折点时的土壤特征指标。结果表明：与单施尿素相比,160 d的时间内两种DMPP用量处理的土壤N2O累积排放减排幅度均为54%,而10%DCD和15%DCD处理的土壤分别减少28%和41%。DMPP和DCD处理50 d和90 d时土壤的NH4＋-N含量均显著高于（p〈0.05）单施尿素处理,而NO3--N含量和表观硝化率则恰好相反,但两种抑制剂间无差异。DMPP处理的AOB群落结构的变化从10 d开始显现,至50 d和90 d时仍保持明显的抑制状态,而DCD处理则至90 d时抑制作用基本消失。单施尿素AOB功能基因（amo A）的丰度均显著高于硝化抑制剂处理（90 d时尿素＋10%DCD处理除外）;在整个培养期内,尿素和对照土壤的AOA群落结构相似,硝化抑制剂反而增加了AOA功能基因的丰度,表明硝化抑制剂对AOA丰度无明显抑制作用。即两种硝化抑制剂主要通过抑制AOB起作用;调节土壤p H至中性范围,并在1%DMPP施用条件下,硝化抑制剂的抑制效果最显著。

英文摘要：

【Objective】Combined application of nitrification inhibitors and ammonium-containing fertilizers is considered an effective means for improving N utilization efficiency and reducing pollution risk. To determine effects of the use of two nitrification inhibitors：dicyandiamide（DCD）and 3,4-dimethylpyrazole phosphate（DMPP）,separately,on N_2O emission,nitrogen transformation rate,and community structure and abundance of ammonia-oxidizing bacteria（AOB）and ammonia-oxidizing archaea（AOA）in soils applied with ammonium-containing fertilizers.【Method】An in-lab incubation test was conducted of soil samples collected from an extensively managed Phyllostachys edulis plantation. The soil samples were subjected to six treatments,separately,that is（1）CK（no fertilizer）;（2）Urea（Urea）;（3）Urea ＋ 1% DMPP（1% of Urea in quantity）;（4）Urea ＋ 1.5% DMPP;（5）Urea ＋ 10% DCD;（6）Urea ＋ 15% DCD. Dynamics of N_2O emissionand soil parameters at the time of N_2O emissionturning point（10 d,50 d and 90 d）were determined. 【Result】Results show that both of the two nitrification inhibitors greatly reduced N_2O emission during the 160 days of incubation. The reduction rate in Treatments Urea ＋ DMPP（both 1% and 1.5%）,Treatment Urea ＋10% DCD,and Treatment Urea ＋15% DCD was 54%,28%,and 41%,respectively. Significant differences were found in cumulative emission of N2O（p〈0.05）between the treatments,but not between the two Urea ＋ DMPP treatments. The treatments in which urea was combined with nitrification inhibitors were similar to Treatment CK in N_2O emission rate during the first 40 days of incubation,and then the formers began to rise gradually with the incubation going on and exceeded CK. Significantly lower N_2O cumulative emission was observed in Treatment Urea ＋15% DCD than in Treatment Urea ＋10% DCD. Soil NH4＋-N levels due to urea application increased rapidly to a maximum and then decreased gradually,with Treatment Ureabeing lower than all the urea ?