南水北调中线干渠(河南段)浮游细菌群落组成及影响因素

摘要

为了解南水北调中线工程通水后干渠河南段浮游细菌群落组成及影响因素,于2016年7月对中线干渠河南段5个典型生态点位表层水样进行采集.水质监测结果表明干渠水质总体较好,除总氮(TN)和高锰酸盐指数(CODMn)外,其他各项指标符合Ⅰ类水标准要求.渠首、方城和新郑3点位水体处于中营养状态,温县、安阳2点位水体处于轻度富营养状态.采用高通量测序技术对浮游细菌群落组成进行研究,结果表明主要由放线菌门(Actinobaeteria)、变形菌门(Proteobacteria)、浮霉菌门(Planctomycetes)、拟杆菌门(Bacteroidetes)、蓝藻门(Cyanobacteria)、疣微菌门(Verrucomicrobia)、装甲菌门(Armatimonadetes)等25个门和407个属组成,5点位样品具有丰富的群落组成,浮游细菌群落多样性排序为:温县＞新郑＞方城＞渠首＞安阳.对浮游细菌群落组成与环境因子的关系进行典范对应分析(CCA),结果表明:TN、Chl a、NH4+-N、COD、CODMn能显著影响浮游细菌群落,pH值和TP对其也有一定程度影响.%To determine which factors may have an impact on the community composition of bacterioplankton,15surface water samples were collected from the main cancel of the Mid-line Project of South-to-North Water Division in 5sections of Henan province,in July 2016,and 7essential environmental factors were evaluated.The results showed that water quality in the main cancel was strongly influenced by total nitrogen (TN) and the permanganate index (CODMn).Water system in Qushou,Fangcheng,and Xinzheng sections was under the mesotrophic state,and in Wenxian and Anyang sections,under the light eutrophic state.High-throughput sequencing was used to analyze distribution characteristics of the community structure,diversity of bacterioplankton.Phylogenetic analysis based on 16S ribosomal DNA sequences revealed that bacterioplankton could be subdivided into 25major phylogenetic and 407genus groups.The dominant phylogenetic groups included Actinobacteria,Proteobacteria,Planctomycetes,Bacteroidetes,Cyanobacteria,Verrucomicrobia,and Armatimonadetes.Diversity of the bacterioplankton community in the main cancel of the Mid-line Project of South-to-North Water Division could be ranked in the following order:Wenxian ＞Xinzheng ＞ Fangcheng ＞ Qushou ＞ Anyang.The results of canonical correspondence analysis (CCA) of the relation between the bacterioplankton and 7 environmental factors showed that TN,ammonia nitrogen (NH4+-N),chlorophyll a (Chl a),chemical oxygen demand (COD),and the CODrMn were the main environmental factors affecting the distribution characteristics of the bacterioplankton community.