我国东北典型河流冰封期细菌多样性的研究——以松花江为例

Bacterial biodiversity in the river in Northeast China during the freezing seasons:A case in Songhua River

在我国东北松花江冰封期时采集了该河流域5个监测断面的河水样本,并分别构建16S rDNA克隆文库,通过16S rDNA序列的系统发育分析,对水样中细菌群落结构和种群多样性进行了研究.试验结果表明,5个采样点的水样pH都呈弱酸性,并且都有不同程度的多环芳烃(PAHs)污染,其中,B(九站)采样点污染最为严重.5个样品中检测到的共同细菌种类有5个:β-变形菌纲(Betaproteobacteria)、γ-变形菌纲(Gammaproteobacteria)、放线菌门(Actinobacteria)、蓝细菌门(Cyanobacteria)和拟杆菌门(Bacteroidetes).5个河水样品中的细菌与许多已知降解菌的亲缘关系较近,并以能降解多环芳烃类有机污染物的微生物种类居多,且在5个样品中均发现了指示河流富营养化的菌种,表明该河流存在普遍的富营养化趋势,特别是D、E段(佳木斯上和佳木斯下)比较严重.

Five water samples were collected from different sites of the Songhua River in Northeast China during the freezing seasons. Community structure and species diversity of bacteria were investigated by constructing each bacterial 16S rRNA gene clone library and performing the phylogenetic analysis. The results showed that the five samples were lightly acidic, and were all contaminated to different degrees by polycyclic aromatic hydrocarbons （PAHs）. The sample B was contaminated more seriously than the others. There were five phyla of bacteria detected from the all five samples, which were Betaproteobacteria, Gammaproteobacteria, Actinobacteria, Cyanobacteria and Bacteroidetes. Many clones were affiliated with degrading bacteria, with the majority of those capable in degrading PAHs. The bacteria indicating eutrophication were detected in all samples, which implied eutrophication in the whole river, especially in the section where sample D and E were collected.