a State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing 210008, People's Republic of China.
Can J Microbiol. 2013 Sep;59(9):611-9. doi: 10.1139/cjm-2013-0212. Epub 2013 Jul 22.
We analyzed the composition and diversity of a bacterial community to determine its response to increasing salinity in the Xiangsi Lake wetland in the arid region of northwest China. We studied 12 sites, ranging from freshwater to saltwater habitats, using polymerase chain reaction (PCR)-based terminal restriction fragment length polymorphism (T-RFLP) and sequencing of the 16S rRNA genes of 5 selected samples. Cluster analysis and phylogenetic analysis revealed that the bacterial community changed significantly in response to increased salinity within the small-scale wetland (50.8 km(2)). Detailed analysis showed that (i) Betaproteobacteria can maintain balanced growth over a salinity range (from 0.34 to 6.86 g/L) through intergenus changes in community structure, followed by a sharp decrease in relative abundance (from 62.2% to 16.0%) when salinity reaches 26.18 g/L; (ii) salt-sensitive and halophobic taxa were progressively replaced by halotolerant and halophilic taxa with increasing salinity; (iii) bacterial diversity was lowest at intermediate salinity levels (6.86 g/L); and (iv) an increasing percentage of unclassified bacterial taxa were found with increasing salinity. This study has implications to improve understanding of bacterial community response to water salinization.
我们分析了一个细菌群落的组成和多样性，以确定其对中国西北干旱地区香水湖湿地盐度增加的响应。我们使用聚合酶链反应（PCR）-基于末端限制性片段长度多态性（T-RFLP）和 5 个选定样本的 16S rRNA 基因测序，研究了 12 个从淡水到咸水栖息地的地点。聚类分析和系统发育分析表明，细菌群落对小尺度湿地（50.8km²）内盐度的增加有显著变化。详细分析表明：（i）β变形菌通过群落结构的种间变化，在盐度范围内（从 0.34 到 6.86g/L）保持平衡生长，当盐度达到 26.18g/L 时相对丰度急剧下降（从 62.2%到 16.0%）；（ii）随着盐度的增加，盐敏感和厌盐类群逐渐被耐盐和嗜盐类群取代；（iii）细菌多样性在中等盐度水平（6.86g/L）最低；（iv）随着盐度的增加，未分类的细菌类群的比例增加。本研究有助于提高对细菌群落对水盐度变化的响应的理解。
