黄河内蒙古段表层沉积物细菌多样性及群落结构类型

为掌握黄河内蒙古段表层沉积物微生物多样性、群落结构类型及其影响因素,采用高通量测序技术分析了6个采样点表层沉积物中的微生物多样性及群落结构。研究结果表明,黄河内蒙古段沉积物细菌丰度大小排序为乌拉特前旗(H3)老牛湾(H6)临河(H2)包头(H4)托县(H5)乌海(H1),微生物多样性排序为H6 H2 H5 H4 H3 H1,乌海沉积物中细菌丰度和微生物多样性都是最低的一个采样点。黄河内蒙古段表层沉积物中三大优势菌群分别为变形菌门(Proteobacteria,相对丰度32.39%)、绿弯菌门(Chloroflexi,13.25%)和拟杆菌门(Bacteroidetes,12.16%)。细菌群落丰度与环境因子之间的冗余分析结果显示,沉积物中总有机碳(TOC)、离子交换容量(CEC)和总磷(TP)、总氮(TN)等环境因子对黄河内蒙古段沉积物细菌群落分布影响较大,负相关系数分别为82.5%、80.1%、85.5%和85.2%;微生物多样性与环境理化因子相关性分析结果表明,黄河沉积物微生物多样性格局与对氮磷等营养物质的损耗有直接关系。

Bacterial diversity and community structure in surface sediments of Yellow River from Inner Mongolia section

The microbial diversity and community structure of surface sediments of Yellow River from Inner Mongolia were analyzed by high-throughput sequencing technique, and the samples were taken from Wuhai (H1), Linhe (H2), Wrad Qianqi (H3), Baotou (H4), Togtoh County (H5) and Laoniuwan (H6). The results showed that the order of bacteria abundance in six surface sediments was H3 > H6 > H2 > H4 > H5 > H1 and the order of diversity was H6 > H2 > H5 > H4 > H3 > H1, with H1 being the lowest in both cases. The three dominant bacteria groups were Proteobacteria (32.39%), Chloroflexi (13.25%) and Bacteroidetes (12.16%) in the sediments of Yellow River from Inner Mongolia through the taxonomy analysis of the sequencing data. The analysis of redundancy between bacterial community abundance and environmental factors indicated that total organic carbon (TOC), ion exchange capacity (CEC), total phosphorus (TP), total nitrogen (TN) and other environmental factors in the sediments had great influence on the distributions of bacterial communities and the negative coefficients were 82.5%, 80.1%, 85.5% and 85.2% respectively. The results of correlation analysis between microbial diversity and environmental physicochemical factors demonstrated that the pattern of microbial diversity in the Yellow River sediments was directly related to the loss of nutrients such as nitrogen and phosphorus.