中文摘要：

摘要：以河北省徐水县长期定位施肥试验田为研究对象，利用末端限制性片段长度多态性（T—RFLP）分析和克隆文库构建，研究了5种施肥处理（清水灌溉CK、无机肥灌溉CF、不同牛场肥水灌溉T4、T5和T11）下土壤中nosZ型反硝化细菌群落多样性及其群落结构演变。结果表明，不同施肥处理下nosZ型反硝化细菌群落多样性无显著性差异，施肥条件对nosZ型反硝化细菌的群落结构无明显影响，说明本试验土壤中nosZ型反硝化细菌对施肥不敏感，群落稳定。系统发育分析结果表明，nosZ型反硝化细菌主要与假单胞菌属（Pseudomonas）具有较近的亲缘关系。

英文摘要：

The community structure and diversity of nosZ-type denitrifying bacteria under various fertilization regimes including control without fertilizers （CK）, conventional fertilization（CF）and cattle fertilizer irrigation treatments in three fertilizer levels（T4, T5, T11） in Xushui, Hebei Province were investigated by the combination of terminal restriction fragment length polymorphism（T-RFLP） analysis and gene sequencing. The results showed that no significantly difference was noted in nosZ-type denitrifying bacteria diversity indexs in all treatments, and fertilization regimes have no significantly influenced on community composition of nosZ-type denitrifying bacteria, indicating that nosZ-type denitrifying bacteria have a stable community structure in 0-5 cm soil of this study. Phylogenetic analysis indicated that the Alcaligene, Rhizobium and nosZ-type denitrifiers were mainly composed of Pseudomonas.