塔克拉玛干沙尘暴源区空气细菌群落多样性

Diversity of airborne bacterial communities in sandstorm area of Taklimakan

【目的】采集新疆塔克拉玛干沙漠腹地和周围沙尘暴源区空气样品,对不同样点沙尘暴发生前期、中期、后期空气细菌进行群落结构解析。阐明新疆沙尘暴源区空气细菌种属特征和群落多样性动态变化规律。【方法】基于Illumina HiSeq测序平台,利用双末端测序方法,构建16S rRNA小片段文库进行测序。【结果】塔克拉玛干沙尘暴源区空气细菌主要分为4门37个属,Proteobacteria占67.6%、Bacteroidetes占17.6%、Actinobacteria占11.7%、Firmicutes占2.9%;在属水平上,新疆沙尘暴源区有8个不同优势属,非度量多维尺度分析表明,不同样点在不同时期的细菌群落组成差异极显著;典范对应分析表明,环境因子对沙尘暴源区空气细菌多样性的影响大小为:海拔>纬度>经度>湿度>气压>温度,且差异不显著。【结论】新疆沙尘暴源区空气细菌群落多样性和丰富度高;不同样点沙尘暴前期、中期、后期的空气细菌群落组成差异极显著;沙尘暴对5个源区固有细菌群落影响差异极显著。

[Objective] Aimed to clarify the dynamic changes of airborne bacterial species and community diversity in sandstorm source areas in Xinjiang, we collected air samples from the dust source areas in the hinterland of Taklimakan and surroundings, and analyzed the community structure of airborne bacteria in the early, middle and late stages of sandstorm occurrence. [Methods] Based on the Illumina Hi Seq sequencing platform, we constructed the 16 S r RNA small fragments library by sequencing using double-end sequencing. [Results] The dust storm source bacteria belonged to 37 genera and affiliated to 4 phyla, and Proteobacteria accounted for 67.6%, Bacteroidetes accounted for 17.6%, Actinobacteria accounted for 11.7%, Firmicutes accounted for 2.9%. At genus level, there were altogether 8 different dominant genera in Xinjiang sandstorm source area, and the Non-metric Multidimensional Scaling result showed the significant differences in bacterial community composition at different sampling sites in different periods. The canonical correspondence analysis showed that the influence of airborne bacterial diversity in sandstorm area with environmental factors was as follows： altitude〉latitude〉longitude〉 humidity〉air pressure〉temperature with no significant difference. [Conclusion] The diversity and abundance of airborne bacterial community in the sandstorm source area in Xinjiang were very high. The differences of air bacterial community composition in the early, middle and late stages of sandstorm were significant in different areas. The influence of sandstorm on the indigenous bacterial communities in the five source areas was extremely significant.