饮用水常规处理工艺中细菌群落的时空分布

为弄清饮用水常规处理工艺过程中细菌群落的时空分布和动态变化规律,以我国南方某市一常规处理工艺水厂为研究对象,采用Illumina HiSeq高通量测序技术对夏季和冬季原水、沉后水、滤后水、出厂水和滤砂生物膜等细菌群落进行解析.结果表明,出厂水pH值、浊度、COD_Mn、菌落总数等指标均满足《生活饮用水卫生标准》（GB5749-2006）的要求.夏季细菌多样性明显高于冬季,混凝沉淀和消毒是影响细菌群落多样性和组成的主要工艺单元.细菌群落组成呈现一定的季节性变化,水样中优势菌门主要包括变形菌门（Proteobacteria）、放线菌门（Actinobacteria）、蓝细菌门（Cyanobacteria）等,在滤砂生物膜样品中,变形菌门（Proteobacteria）亦占绝对优势.在属水平上,检测到的条件致病菌属包括弧形菌属（Vibrio）、不动杆菌属（Acinetobacter）和分支杆菌属（Mycobacterium）.水温和溶解氧是影响细菌群落的主要水质参数.     

饮用水常规处理工艺中细菌群落的时空分布

为弄清饮用水常规处理工艺过程中细菌群落的时空分布和动态变化规律,以我国南方某市一常规处理工艺水厂为研究对象,采用Illumina HiSeq高通量测序技术对夏季和冬季原水、沉后水、滤后水、出厂水和滤砂生物膜等细菌群落进行解析.结果表明,出厂水pH值、浊度、COD_Mn、菌落总数等指标均满足《生活饮用水卫生标准》（GB5749-2006）的要求.夏季细菌多样性明显高于冬季,混凝沉淀和消毒是影响细菌群落多样性和组成的主要工艺单元.细菌群落组成呈现一定的季节性变化,水样中优势菌门主要包括变形菌门（Proteobacteria）、放线菌门（Actinobacteria）、蓝细菌门（Cyanobacteria）等,在滤砂生物膜样品中,变形菌门（Proteobacteria）亦占绝对优势.在属水平上,检测到的条件致病菌属包括弧形菌属（Vibrio）、不动杆菌属（Acinetobacter）和分支杆菌属（Mycobacterium）.水温和溶解氧是影响细菌群落的主要水质参数.     

旅游活动对岩溶洞穴地下水中细菌群落的影响:以重庆丰都两个洞穴为例

为了深入了解岩溶洞穴地下水中细菌群落结构特征以及评估旅游活动对细菌群落的影响,对重庆丰都雪玉洞(旅游洞穴)和水鸣洞(未开发洞穴)洞穴地下河水进行了采样,利用16S rDNA高通量测序技术对地下水样品中的细菌进行了定性和定量分析.结果表明,两个洞穴地下水中细菌群落以变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes)为主,但细菌群落组成存在差异.雪玉洞地下河上游和下游的变形菌门分别占总群落的62%和64%,拟杆菌门分别占11%和16%;水鸣洞地下水中细菌优势群落除变形菌门(38%)和拟杆菌门(19%)外,绿菌门(Chlorobi)占24%,两个洞穴地下水中变形菌门的纲分类均为γ-变形菌纲.γ-变形菌纲(γ-Proteobacterium)和拟杆菌为两个洞穴地下水的优势种类但其主要细菌存在差异:雪玉洞主要细菌是不动杆菌属(Acinetobacter)、假单胞菌属(Pseudomonas)和黄杆菌科(Flavobacteriaceae),属于致病菌;水鸣洞主要细菌是未培养的甲基球菌科(Methylococcaceae-uncultured)、甲基单胞菌属(Methylomonas)以及甲基杆菌属(Methylobacter),属于甲烷氧化细菌.多样性指数分析结果显示:受旅游活动的强烈影响,雪玉洞群落多样性明显高于水鸣洞并且存在更多的致病菌群落,地下水细菌群落与环境因子多元直接梯度分析(RDA)证明群落分布规律受游客数量与洞穴空气CO_2影响且呈正相关,两种环境因子的Spearman相关性分析进一步表明游客数量对地下水细菌群落结构的影响更明显并导致大量原生细菌消失.     

嘉陵江不同干扰断面河道沉积物细菌群落多样性

为探究不同人为扰动对自然河流生态环境的影响,以嘉陵江河道沉积物细菌群落为研究对象,利用高通量测序技术分析工程干扰、支流干扰、采砂干扰、垦殖干扰和无干扰断面河道沉积物细菌的群落组成和功能变化.结果表明,嘉陵江不同干扰断面河道沉积物理化性质和细菌群落多样性均具有显著差异(P<0.05).无干扰断面细菌群落多样性最高,同时,采砂干扰和无干扰断面细菌群落均匀度最高,而支流干扰和垦殖干扰均导致细菌群落多样性和均匀度降低.工程干扰对细菌群落组成的影响显著区别于其他4种干扰断面.细菌优势菌门为变形菌门(Proteobacteria)、放线菌门(Actinobacteriota)、酸杆菌门(Acidobacteriota)和绿弯菌门(Chloroflexi),优势菌纲为γ-变形菌纲(γ-Proteobacteria)、α-变形菌纲(α-Proteobacteria)和Vicinamibacteria纲.采砂干扰导致放线菌门增加,工程干扰促进了酸杆菌门的增加.含水率、有机碳、总氮和总磷是影响沉积物微生物群落变化的主要环境因子.细菌群落主要涉及新陈代谢、遗传信息处理、环境信息处理和细胞过程这4类一级...     

滞流工况下管网水中微生物群落对铁释放的影响

为探究不同供水管道滞流过程中,管网水细菌数量和微生物群落结构对铁释放影响作用,研究依托搭载于实际供水管网中的试验平台,分别采用传统R2A培养法计数可培养腐蚀细菌数量,和高通量测序分析水中微生物群落结构.结果显示,滞流过程中不同管材管网水微生物群落以变形菌门(Proteobacteria)为主,占到86.69%~91.36%.在纲水平上,a-变形菌纲(Alphaproteobacteria)、β-变形菌纲(Betaproteobacteria)和放线菌纲(Actinobacteria)含量较高,可达50%以上.总铁浓度与铁氧化细菌和硫酸盐还原菌的相关性较强,且球墨铸铁管管网水中腐蚀细菌对总铁释放的影响性相较于HDPE管的要大.通过相关性系数分析和RDA分析,门水平上Proteobacteria、Actinobacteria和Acidobacteria以及纲水平上的Alphaproteobacteria、Betaprotebacteria和Bacilli对铁释放起到促进作用.     

北海湖微生物群落结构随季节变化特征

分别于夏季、秋季、冬季和春季采集北海湖水样,进行水质和微生物群落结构分析.水质分析表明,夏季和秋季的水质较冬季和春季差,其中TN和TP是影响水质的最重要因素.通过Mi Seq高通量测序分析微生物群落结构表明:蓝细菌门(Cyanobacteria)、变形菌门(Proteobacteria)、放线菌门(Actinobacteria)和拟杆菌门(Bacteroidetes)是湖水中的优势门,但在不同季节的分布不同.夏季和秋季微生物的多样性高,蓝细菌门(Cyanobacteria)是第一优势菌门(32.7%~43.2%),其中聚球藻属(Synechococcus)是优势蓝细菌.冬季变形菌门(Proteobacteria)的含量相对丰富,占细菌群落的34.8%~40.4%.而春季,放线菌门(Actinobacteria)和拟杆菌门(Bacteroidetes)的含量增加,两者之和占细菌群落的51.5%~64.3%.RDA(redundancy analysis)分析表明,水温是影响北海湖微生物群落结构的最主要环境因子.总体而言,北海湖水质符合景观水的标准,但夏季聚球藻属(Synechococcus)的大量繁殖使北海湖发生水华的风险增加,因此要加强对北海湖水质检测和管理.     

海水养殖尾水直排对河道沉积物细菌群落的影响

海水养殖活动对周边水域沉积物生态环境的影响日益受到关注,微生物群落是反映环境质量变化的一个重要指标.本研究采集了养殖区进出水河道4个位点(1个进水渠位点、出水口和2个出水渠位点)的沉积物,通过Illumina MiSeq测序技术测定细菌16S rRNA基因,利用磷脂脂肪酸(phospholipid fatty acid,PLFA)技术对沉积物中的微生物群落进行半定量分析,研究海水养殖尾水直接排放对河道沉积物细菌群落结构的影响.结果表明,4个位点中变形菌门(Proteobacteria)为优势细菌类型,主要包括γ-变形菌纲(γ-Proteobacteria)、δ-变形菌纲(δ-Proteobacteria)和α-变形菌纲(α-Proteobacteria).受养殖尾水排放影响,沉积物微生物生物量明显升高,放线菌门相对丰度降低而拟杆菌门相对丰度升高,氨氧化微生物相对丰度降低.非度量多维尺度(non-metric multidimensional scaling,NMDS)分析表明大部分沉积物细菌群落按位点聚类.多样性分析表明,未受养殖尾水影响的沉积物细菌群落多样性高于受养殖尾水影响的位点.冗余分析(redundancy analysis,RDA)表明氨氮与底泥沉积物细菌群落结构的相关性最大,对细菌群落的影响最明显.综上,养殖废水直排明显改变了养殖场河道沉积物物理化学性质和细菌群落结构,说明养殖废水的长期直排已严重污染河道环境,并可能会进一步对近海生态环境造成威胁.     

模拟及实际根系分泌物对芘污染土壤微生物群落的影响

为了解根系分泌物对芘污染土壤中微生物群落的影响,应用Illumina NovaSeq高通量测序技术,研究了模拟根系分泌物和实际黑麦草根系分泌物添加至芘污染土壤后,细菌群落组成、α和β多样性以及基因功能的变化.结果 表明,根系分泌物未明显改变芘污染土壤细菌群落的组成,土壤细菌群落中主要优势菌门为变形菌门、放线菌门、厚壁菌...     

人工湿地污水处理系统春季空气微生物群落结构分析?

通过构建16S/18S rDNA基因文库,分析自由表面流人工湿地污水处理系统春季空气细菌和空气真菌群落结构特征.结果表明,空气细菌分布在变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、浮霉菌门(Planctomycetes)、蓝藻门(Cyanophyta)、绿弯菌门(Chloroflexi)、拟杆菌门(Bacteroidetes)和厚壁菌门(Firmicutes),主要为β-变形菌纲(71.04%)、γ-变形菌纲(12.03%)、α-变形菌纲(3.83%)、蓝藻纲(4.38%)、芽孢杆菌纲(3.28%)和鞘脂杆菌纲(2.19%),优势菌属是马赛菌属(Massilia 66.66%)、假单胞菌属(Pseudomonas 4.37%)、蓝丝细菌属(Cyanothece 3.83%)和沙雷氏菌属(Serratia 3.28%).空气真菌主要类群为座囊菌纲(Dothideomycetes 61.18%),其次是接合菌纲(Zygomycetes 16.47%)、盘菌纲(Discomycetes 14.12%),优势菌属是核腔菌属(Pyrenophora 48.31%)、被孢霉属(Mortierella 15.7%)、缘刺盘菌属(Cheilymenia 12.4%)、Boothiomyces (4.5%).人工湿地空气微生物中未检测出大肠杆菌(Escherichia coli)、沙门氏菌(Salmonella spp.)和产气荚膜梭菌(Clostridium perfringens),但存在粘质沙雷氏菌(S. marcescens)、恶臭假单胞菌(P. putida)、表皮葡萄球菌(Staphylococcus epidermidis)等致病菌或条件致病菌.     

农村污水膜生物反应器系统中微生物群落解析

农村污水的随意排放和未加限制的灌溉回用可能会导致水源地环境污染加剧,并且其中潜在的病原微生物对周边淡水资源安全和农村居民的身心健康造成潜在的威胁.为了解农村污水的微生物群落组成,为后续污水灌溉的病原微生物风险评价提供理论依据,采用末端限制性片段长度多态性(T-RFLP)和16S r DNA基因克隆文库技术研究农村污水膜生物反应器(MBR)系统中的微生物群落多样性,并结合实时荧光定量PCR方法监测处理前后典型病原菌——弓形菌(Arcobacter spp.)以及总细菌数量的变化.从未处理的农村污水中获取的73个阳性克隆测序结果表明,其主要细菌类群为变形菌门(91.8%)、厚壁菌门(2.70%)、拟杆菌门(1.40%),以及部分不可培养细菌(4.10%).其中弓形菌属是ε-变形菌门的优势菌,也是农村污水中的优势菌株,占克隆总数的68.5%.TRFLP的结果表明,不同处理工艺阶段的主要细菌类群及丰度明显不同,调节池的物种丰度(S)、Shannon-Wiener(H)和物种均匀度(E)最高,分别为43.0、3.56和0.95.定量PCR结果显示未处理的农村污水中弓形菌数量高达(1.09±0.064 0)×1011copies·L-1,该结果与克隆文库结果均表明弓形菌在污水中确实占较高比例.与未处理的农村污水相比,处理后的出水中所监测的弓形菌及细菌总拷贝数分别减少了2~3个数量级,说明MBR处理系统在一定程度上能够去除微生物.处理后的再生水理化指标及指示菌卫生指标均符合农田灌溉用水标准,但其中残留病原微生物引发的健康风险仍需进一步评价.     

Revealing the changes of bacterial community from water source to consumers tap: A full-scale investigation in eastern city of China

This study profiled the bacterial community variations of water from four water treatment systems, including coagulation, sedimentation, sand filtration, ozonation-biological activated carbon filtration (O₃-BAC), disinfection, and the tap water after the distribution process in eastern China. The results showed that different water treatment processes affected the bacterial community structure in different ways. The traditional treatment processes, including coagulation, sedimentation and sand filtration, reduced the total bacterial count, while they had little effect on the bacterial community structure in the treated water (before disinfection). Compared to the traditional treatment process, O₃-BAC reduced the relative abundance of Sphingomonas in the finished water. In addition, ozonation may play a role in reducing the relative abundance of Mycobacterium. NaClO and ClO₂ had different effects on the bacterial community in the finished water. The relative abundance of some bacteria (e.g. Flavobacterium, Phreatobacter and Porphyrobacter) increased in the finished water after ClO₂ disinfection. The relative abundance of Mycobacterium and Legionella, which have been widely reported as waterborne opportunistic pathogens, increased after NaClO disinfection. In addition, some microorganisms proliferated and grew in the distribution system, which could lead to turbidity increases in the tap water. Compared to those in the finished water, the relative abundance of Sphingomonas, Hyphomicrobium, Phreatobacter, Rheinheimera, Pseudomonas and Acinetobacter increased in the tap water disinfected with NaClO, while the relative abundance of Mycobacterium increased in the tap water disinfected with ClO₂. Overall, this study provided the detailed variation in the bacterial community in the drinking water system.     

Determination of N-nitrosodimethylamine in drinking water by UPLC-MS/MS

The method for detecting N-nitrosodimethylamine (NDMA) in drinking water using ultra performance liquid chromatography (UPLC) coupled with tandem mass spectrometry (MS/MS) was improved by optimizing the clean-up procedure to remove the matrix interference in pretreatment process, and was then applied to a survey of NDMA in both raw and finished water samples from five water treatment plants in South China. The NDMA concentrations ranged from 4.7 to 15.1 ng/L in raw water samples, and from 4.68 to 46.9 ng/L in finished water. The NDMA concentration in raw water was found to be related with nitrite concentration, and during the treatment, the NDMA concentration increased following ozonation but decreased after subsequent activated carbon treatment.     

再生水补水对河流湿地香蒲根际细菌群落结构影响研究

以典型的再生水补水河流湿地为例,采用末端限制性片段长度多态性技术(T-RFLP)分析河道不同空间香蒲根际细菌群落结构差异,并借助单因素方差分析(one-way ANOVA)、Spearman等级相关分析和典范对应分析(CCA)方法解析麻峪湿地香蒲根际细菌群落结构空间差异特征的形成原因,以揭示再生水补水过程对河道湿地香蒲根际细菌群落的影响,并尝试找出空间差异形成的驱动因子.结果表明:随再生水干扰强度的增加,各类群细菌群落的丰富度、均匀度及多样性均呈现不同程度的降低趋势;其中γ-变形菌门(Gammaproteobacteria)、δ-变形菌门(Deltaproteobacteria)和绿弯菌门(Chloroflexi)、ε-变形菌门(Epsilonproteobacteria)和放线菌门(Actinobacteria)在再生水影响下均显著降低(P<0.05).Spearman等级相关分析显示pH值、DO(溶解氧)、TDS(总溶解固体)、ORP(氧化还原电位)、Sal(盐度)和NH₄⁺-N(氨氮)与植物根际细菌群落多样性空间演替紧密相关.CCA分析结果进一步表明再生水补水口的上游细菌群落与TN(总氮)、TOC(总有机碳)及重金属Cr、Ni、Cu具有密切关系,这可能与这些污染物累积效应有关;补水口附近植物根际细菌群落则因补水口再生水水质不同而具显著差异,其中第Ⅱa类群主要受到水质变量pH值影响较大,而第Ⅱb类群与T(温度)、ORP和NH₄⁺-N具有较高的相关性;补水口的下游细菌群落则因水体内源杂质及人为活动影响而同样与TOC及持久性痕量重金属生物循环密切相关.     

Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis （DGGE） of nested polymerase chain reaction （nested PCR） amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.     

Characterization of bacterial community dynamics in a full-scale drinking water treatment plant

Understanding the spatial and temporal dynamics of microbial communities in drinking water systems is vital to securing the microbial safety of drinking water. The objective of this study was to comprehensively characterize the dynamics of microbial biomass and bacterial communities at each step of a full-scale drinking water treatment plant in Beijing, China. Both bulk water and biofilm samples on granular activated carbon (GAC) were collected over 9 months. The proportion of cultivable cells decreased during the treatment processes, and this proportion was higher in warm season than cool season, suggesting that treatment processes and water temperature probably had considerable impact on the R2A cultivability of total bacteria. 16s rRNA gene based 454 pyrosequencing analysis of the bacterial community revealed that Proteobacteria predominated in all samples. The GAC biofilm harbored a distinct population with a much higher relative abundance of Acidobacteria than water samples. Principle coordinate analysis and one-way analysis of similarity indicated that the dynamics of the microbial communities in bulk water and biofilm samples were better explained by the treatment processes rather than by sampling time, and distinctive changes of the microbial communities in water occurred after GAC filtration. Furthermore, 20 distinct OTUs contributing most to the dissimilarity among samples of different sampling locations and 6 persistent OTUs present in the entire treatment process flow were identified. Overall, our findings demonstrate the significant effects that treatment processes have on the microbial biomass and community fluctuation and provide implications for further targeted investigation on particular bacteria populations.     

Characterization of the airborne bacteria community at different distances from the rotating brushes in a wastewater treatment plant by 16S rRNA gene clone libraries

Biological risks of bioaerosols emitted from wastewater treatment processes have attracted wide attention in the recent years. However, the culture-based analysis method has been mostly adopted for detecting the bacterial community in bioaerosols, which may result in the underestimation of total microorganism concentration as not all microorganisms are cultivable. In this study, oligonucleotide fingerprinting of 16S rRNA genes was applied to reveal the composition and structure of the bacterial community in bioaerosols from an Orbal oxidation ditch in a Beijing wastewater treatment plant (WWTP). Bioaerosols were collected at different distances from the aerosol source, rotating brushes, and the sampling height was 1.5 m which is the common respiratory height of a human being. The bacterial communities of bioaerosols were diverse, and the lowest bacterial diversity was found at the sampling site just after the rotating brush rotating brush. A large proportion of bacteria in bioaerosols were affiliated with Proteobacteria and Bacteroidetes. Numerous bacteria present in the bioaerosols also emerged in water, indicating that the bacterial community in the bioaerosols was related to that of the aerosols’ sources. The forced aeration of rotating brushes brought about observably distinct bacterial communities between sampling sites situated before and after the rotating brush. Isolation sources of closest relatives in bioaerosols clone libraries were associated with the aqueous environment in the WWTP. Common potential pathogens in bioaerosols as well as those not reported in previous research were also analyzed in this study. Measures should be adopted to reduce the emission of bioaerosols and prevent their exposure to workers.     

黄浦江原水中土臭素冬季超标机制研究

基于黄浦江原水中土臭素浓度出现的季节性超标现象,采用高通量测序技术对比分析了夏、冬季微生物群落结构差异,发现夏、冬季水样中微生物群落结构差异显著.土臭素浓度较低的夏季水样中相对丰度较高的微生物为Microcystis、Synechococcus等蓝藻类微生物,其与嗅味物质的合成相关且易于汇集到沉积物内,导致夏季水样与冬季沉积物微生物种群相关;冬季水样中丰度较高的微生物主要为Flavobacterium、Candidatus Pelagibacter、Limnohabitans等水华蓝藻分解微生物,由此推测夏季增殖并汇集于沉积物的水华蓝藻分解是导致原水冬季土臭素超标的主要原因.本研究基于微生物种群结构分析提出了冬季原水中嗅味物质超标的可能机制,为饮用水原水嗅味污染控制提供了理论参考.     

不同排海方式城市尾水微生物扩散规律

尾水中含有大量病原菌,回用或排入自然水体后会对人群健康和生态安全构成威胁.为了探究不同排海方式对微生物扩散规律的影响,本研究利用高通量测序技术对春季污水处理厂尾水细菌群落结构、优势菌群、典型致病菌及其随扩散距离的变化进行研究.结果发现,先排河后排海的尾水物种更加丰富,分布在58个菌纲,相对丰度大于1%的细菌有32种,而直接排海的尾水中仅有41个菌纲,相对丰度大于1%的细菌有28种.相对于直排过程,间排方式微生物群落结构相对丰度更高,说明尾水的直接排海使得微生物更易扩散.同一污水处理厂优势菌门所占比例随着扩散距离的增大整体呈下降趋势,蓝藻菌门(Cyanobacteria)等由于在自然水体中的高浓度出现随扩散距离增大整体上升的趋势.两个系统的优势菌门都属于变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)及厚壁菌门(Firmicutes),纲、种水平重合度较低,但整体来讲排污口附近微生物多样性及丰度远高于海水(空白样品),且污水处理相关菌种丰度较高.另外,尾水中存在一定量的致病菌和条件致病菌,其中Pseudoalteromonas haloplanktis、Pseudomonas anguilliseptica致病性极强,扩散后相对丰度仍然很高,且弓形杆菌属(Arcobacter spp.)与人类和动物的腹泻、菌血症等疾病密切相关.因此,尾水排放过程中应对这几种细菌重点监测.