平原河网沉积物细菌与重金属生态风险的定量响应关系研究  

Quantitative response of sediment bacteria to ecological risk of heavy metals in plain river network

作　　者：马星琢 余春瑰 金春玲 段高旗 彭剑峰 袁鹏[3] 李艳红[1] MA Xingzhuo;YU Chungui;JIN Chunling;DUAN Gaoqi;PENG Jianfeng;YUAN Peng;LI Yanhong(School of Environmental Science and Engineering,Guilin University of Technology,Guilin 541004;Center for Water and Ecology,School of Environment,Tsinghua University,Beijing 100084;Basin Research Center for Water Pollution Control,Chinese Research Academy of Environmental Sciences,Beijing 100012)

机构地区：[1]桂林理工大学环境科学与工程学院,桂林541004 [2]清华大学环境学院,清华大学水质与水生态研究中心,北京100084 [3]中国环境科学研究院流域水环境污染综合治理研究中心,北京100012

出　　处：《环境科学学报》2023年第11期372-383,共12页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金面上项目(No.52070118)。

摘　　要：河道沉积物重金属对河底生态环境质量有着深远的影响.太湖流域河网纵横,人水关系密切,河网环境质量受到人类活动的影响.为掌握河网表层沉积物重金属空间分布特征与强度,本研究以太湖流域嘉善县纵横交错的河网为研究对象,使用潜在生态风险指数评价法(the Potential Ecological Risk Index,PERI)对51个点位的Hg、Cd、Cu等9种重金属的单因子及综合生态风险水平进行评估.通过相关性分析和方差分解表征沉积物重金属对于细菌群落整体的影响.为研究沉积物细菌群落对重金属生态风险指数的响应特征,基于16S rDNA扩增子高通量测序获得的群落信息,使用临界指示物种分析法(Threshold Indicator Taxa Analysis,TITAN)建立群落与风险指数的定量响应关系.研究发现,此区域15.69%点位的沉积物存在重金属“中等”及以上生态风险;Cd、Ni、Pb显著影响细菌群落的α-多样性.定量分析表明,群落中共441个生物序列可操作分类单元(Operational taxonomic units,OTUs)对综合生态风险指数存在有效响应,234个OTUs对一种或一种以上单因子风险指数存在有效响应.当综合风险指数分别为80.78与106.26,群落中正、负响应物种类群丰度发生最大幅度的变化.沉积物重金属生态风险主要来自于Hg和Cd.有97个OTUs分别对Hg或Cd的生态风险有预警及指示意义,其中,属于Anaerolineales或Burkholderiales菌目的较多.本研究创新性地将PERI法和高通量测序技术结合到TITAN法中,研究了细菌群落与重金属生态风险指数的定量响应关系,为重金属污染生态风险监测、评估提供了新的思路.Heavy metals in river sediment have a considerable impact on the biological condition of the riverbed.River networks intersect the Lake Taihu Basin.The environmental health of the river network is inextricably linked to humans and can be influenced by a variety of human activities.Jiashan County’s crisscrossing river network of the Lake Taihu basin was chosen as the research object to study the spatial distribution and intensity of heavy metal risk in the surface sediment.The Potential Ecological Risk Index(PERI)was used to assess nine single factors and the overall ecological risk levels of 51 locations across the county.The effects of heavy metals in sediment on the bacterial community were characterized using correlation analysis and Variance Partitioning Analysis(VPA).Based on the results of 16S rDNA amplicon high-throughput sequencing and PERI analysis,Threshold Indicator Taxa Analysis(TITAN)was used to establish quantitative response relationship between bacterial community and risk index.It was discovered that 15.69%of the sediments in this area had an ecological risk of heavy metals of"Medium"or higher.Cd,Ni and Pb all had a significant impact on the α-diversity of the bacterial community.Furthermore,quantitative research revealed that 441 operational taxonomic units(OTUs)responded effectively to the overall ecological risk index,and 234 OTUs had an effective response to one or more single factor risk indexes.The abundance of positive and negative response species changed the most when the total risk score was 80.78 and 106.26,respectively.Our findings supported the idea that the ecological risk of heavy metals in sediments mainly came from Hg and Cd.There identified 97 OTUs with early warning and suggestive relevance for Hg or Cd ecological concerns,with the majority belonging to Anaerolineacea or Burkholderiales.In this study,the PERI approach and high-throughput sequencing technology were integrated in an innovative way with the TITAN method to study the quantitative response relationship between th

关 键 词：生态阈值 指示物种 临界指示物种分析法(TITAN) 高通量测序 群落响应 太湖流域 

分 类 号：X820.4[环境科学与工程—环境工程] X171