南明河城区河段细菌多样性与环境因子的关系

Association of bacterial diversity in city area of Nanming river with environmental factors

【目的】了解南明河城区河段细菌群落结构及多样性变化,探讨城区河段环境因子对细菌群落结构的影响。【方法】应用对细菌16S r DNA V4区的高通量测序技术,分析和比较了南明河流经城区的5个样点的细菌群落多样性;然后采用冗余分析(RDA)探讨了水体环境因子与细菌多样性的关系。【结果】南明河贵阳区段细菌多样性指数(Shannon-Wiener指数)分析结果显示,多样性指数平均达7.5,乌当桥采样点的细菌多样性>水口寺采样点>五眼桥采样>花溪大桥采样点>冠洲桥采样点。序列比对结果显示,南明河内细菌除了部分分类地位不明确的菌群和稀有菌群外,其余分布于11个门包含327个属的细菌,优势菌门为变形菌门(Proteobacterice,66.1%±3.30%),其中γ-变形菌纲(Gammaproteobacteria,54.76%±4.86%)为优势亚群,假单胞菌属(Pseudomonas,16.92%±0.02%)为优势菌属;RDA结果表明不同菌群受不同环境因子的影响不同,菌属群落Ⅳ和环境中总氮、总磷显著正相关。【结论】高通量测序分析能获得更为全面的细菌群落多样性信息。河流经过城区后环境因子发生较大变化,影响河流细菌群落结构改变。这为研究河流城市区段的细菌结构多样性及与环境因子的关系提供了新的科学数据。

[ Objective] The aim of this study was to analyze the bacterial diversity of urban section of Nanming river as well as to study relationship between the bacterial diversity and environmental factors. [ Methods] The high throughput sequencing on PCR-amplified 16S rDNA V4 fragments was used to determine the bacterial diversity of samples from five sites of Nanming river. The ordination technique of redundancy analysis was used to analyze the effects of the environmental factors on bacterial community composition. [ Results I Diversity index analysis of bacterial community composition in Nanming river showed that the Shannon-Wiener index of bacterial diversity in Nanmng River was about 7.5. The Shannon-Wiener index of 5 sampling site had an order as Wudang bridge 〉 Shuikou Si 〉 Wuyan bridge 〉 Huaxi bridge 〉 Guanzhou bridge. Based on the sequencing results, there were 11 phyla （327 genera） in the samples, of which proteobacterice （66. 1%±3.30% ） was the dominant phyla, Gamma proteobaeteria （54.76%±4.86%） was the dominant subgroup and Pseudomonas （16.92%±0.02%） was the dominant genera. In addition, there are some flora and rare flora undetermined. The result of RDA suggested that the influence of different environmental factors on different microbes were different. Bacterial community 1V had significant positive correlation with total nitrogen and total phosphorus in the environment. [ Conclusion ] This research provides references for the association of bacterial composition and diversity with environmental factors.