辉腾锡勒草原干涸湖泊中氨氧化微生物群落结构分析  

Community structure of ammonia-oxidizing prokaryotes at the dry-up lake in Huitengxile grassland

作　　者：惠丽华[1] 赵吉[2,3] 武琳慧[2] 邵玉琴[2] 李靖宇[1] 朱兵[1] 

机构地区：[1]内蒙古大学生命科学学院,呼和浩特010021 [2]内蒙古大学环境与资源学院,呼和浩特010021 [3]中美生态能源及可持续性科学内蒙古研究中心,呼和浩特010021

出　　处：《微生物学报》2012年第1期104-113,共10页Acta Microbiologica Sinica

基　　金：国家"973项目"前期研究专项(2009CB125909);国家自然科学基金(31160129);科技部"国家科技支持计划课题"(2011BAC02B03)~~

摘　　要：【目的】以内蒙古辉腾锡勒草原九十九泉湿地为对象,研究湖泊干涸过程中氨氧化微生物的群落结构及其变化。【方法】通过MPN-PCR定量测定氨氧化古菌(AOA)和氨氧化细菌(AOB)的数量;构建amoA基因克隆文库,进行系统发育分析;结合土壤环境因子,探讨湿地退化过程中影响氨氧化微生物的潜在因素。【结果】依湖泊湿地退水梯度的不同样点中,有75%的样点AOB的数量高于AOA,AOB与AOA的数量比率为0.3-18.1。从湖心到湖岸草原带,AOA和AOB的数量有明显增加,但生物多样性呈降低趋势,二者没有呈现正相关。研究发现,AOB的数量与土壤中NH 4+-N的变化存在良好响应。系统发育分析显示,退化湖泊湿地AOA克隆序列均来自于泉古菌门(Crenarchaeota);AOB的amoA基因的克隆序列大部分与亚硝化单胞菌属(Nitrosomonas)有一定同源性,较少部分与亚硝化螺菌属(Nitrosospira)有一定同源性。【结论】湖泊退水过程增加了湿地土壤氨氧化微生物的数量,而氨氧化微生物的种群丰度有所降低。AOA和AOB群落对湖泊湿地的退化过程做出了响应,其中AOB的响应较为明显,氧化条件和土壤铵浓度的改变可能是促成这种响应的重要原因。[ Objective] To investigate the structure of ammonia-oxidation microbial communities in the wetlands to dry-up process at 99 degraded lakes of the Huitengxile grassland in the Inner Mongolia Plateau. [ Methods ] The microbial quantity of ammonia-oxidizing archaea （AOA） and ammonia oxidizing bacteria （AOB） were examined by most probable number- polymerase chain reaction （MPN-PCR）. The clone libraries of amoA were constructed and phylogenetics were analyzed. With analysis of the soil properties, we evaluated the effects of wetlands degradation on ammonia-oxidation microbes communities. [ Results] In 75% of the samples, the quantity of AOB communities was higher than that of AOA; moreover, quantity of bacterial were up to 18. I-fold more abundant than Archaea＇s. The AOB microbial quantity was strongly correlated with NH4^＋-N content in the soil. Phylogenetic analyses of the amoA gene fragments showed that most AOB sequences from degraded wetlands were affiliated with Nitrosomonas-like species and a few close to Nitrosospira. All AOA sequences belonged to the kingdom Crenarchaeote. [ Conclusion ] Experimental results showed that quantity of ammonia-oxidation microbes increased but community diversity declined during wetlands degradation , and oxidation conditions and ammonium concentration in the soil might play important roles in the community structure of both the AOA and AOB.

关 键 词：湖泊干涸 MPN-PCR 氨氧化古菌 氨氧化细菌 生物多样性 

分 类 号：Q938[生物学—微生物学]