中文摘要：

为揭示亚热带不同森林类型对土壤氨氧化菌群落特征的影响，采用荧光定量PCR以及PCR-DGGE技术研究了阔叶林、杉木林、马尾松林和毛竹林土壤氨氧化古菌和细菌丰度及古菌群落结构特征．结果表明：不同林分土壤中氨氧化古菌数量（1．62×10^6-1．88×10^7个·g-1干土）高于相应土壤中的氨氧化细菌（2．41×10^5～4．36×10^5个·g-1干土）；毛竹林土壤氨氧化古菌数量显著高于杉木林，而后者又显著高于阔叶林和马尾松林，但氨氧化细菌数量在不同林分之间没有显著差异．DGGE图谱分析表明，不同林分土壤中氨氧化古菌的物种有所差异，且毛竹林和杉木林土壤古菌群落结构迥异．氨氧化古菌在亚热带主要林分土壤中表现出明显优势，且除植被类型外，土壤速效钾、pH和有机质是引起土壤氨氧化古菌群落结构及多样性变异的主要因素．

英文摘要：

To investigate the effects of different forest stands in subtropical China on the communi- ties of soil ammonia-oxidizing microorganisms, we characterized the abundance of ammonia-oxidi- zing archaea （AOA） and bacteria （AOB） , and the community structure of AOA in soils under stands of broad-leaved （BF） , Chinese fir （CF） , Pinus massoniana （PF） and moso bamboo （MB） forests using real-time quantitative PCR and denaturing gradient gel electrophoresis （DGGE）. The results showed that the AOA gene copy numbers （ 1.62×10^6-1.88×10^7 per gram of dry soft） were significantly higher than those of AOB genes （2.41×10^5-4.36×10^5 per gram of dry soil）. Signifi- cantly higher soil AOA abundance was detected in the MB than that in the CF （P〈0.05） , and the latter was significantly higher than that in the BF and PF soils （ P〈0.05 ）. There were no signifi- cant differences in the soil AOB abundance among the four forest stands. As indicated by DGGE pattern, soil AOA species varied among the four forest stands. There was a difference in the soil AOA communities between the CF and MB stands. The AOA demonstrated a competitive advantage over the AOB in the soils under these major subtropical forests. Soil pH, concentrations of soil available potassium and organic carbon as well as the forest type were the main factors that influence the variation of AOA community structure and diversity.