富营养化对小型湖泊浮游甲壳动物群落结构及多样性的影响

2017年3月到2018年2月研究了临涣湖浮游甲壳动物群落结构的季节变化。临涣湖共记录浮游甲壳动物13种,其中枝角类8属8种,桡足类5属5种。短尾秀体溞(Diaphanosoma brachyurum)、广布中剑水蚤(Mesocyclops leuckarti)和象鼻溞(Bosmina sp.)等小型富营养种类是温暖季节的优势种,而近邻剑水蚤(Cyclops vicinus)是冬季的优势种。盔形溞(Daphnia galeata)等大型种类仅在少数月份中被观察到。临涣湖浮游甲壳动物的年平均密度和生物量分别为28.3个/L和0.33 mg/L。营养状态指数(TSI_M)的年平均值为62.6。浮游甲壳动物的Shannon指数、Pielou指数和Simpson指数的年平均值分别为0.86、0.74和0.49,且3种多样性指数均具有显著的季节差异。营养盐水平、营养状态指数和物种多样性指数均表明,临涣湖水体处于富营养化状态。冗余分析结果表明,水温、总磷浓度和叶绿素a浓度是影响临涣湖浮游甲壳动物群落结构变化的上行效应因子。鲢、鳙鱼的捕食压力是临涣湖浮游甲壳动物群落结构小型化的下...     

乌梁素海浮游细菌群落结构及其对富营养化因子的响应

【目的】揭示乌梁素海浮游细菌的群落结构及其对富营养化环境因子的响应,认识乌梁素海浮游细菌多样性,以丰富微生物与富营养化关系的理论。【方法】提取水体浮游细菌总DNA,利用细菌通用引物对63F/1387R进行PCR扩增,构建小口、沙尖北和红圪卜3个湖区16S rRNA基因克隆文库;以典型对应分析(CCA)方法解析浮游细菌群落结构对环境因子的响应。【结果】各湖区中富营养化程度最重的红圪卜位点细菌多样性、丰富度及均匀度最高,而富营养化程度最轻的小口位点细菌多样性、丰富度及均匀度最低。Proteobacteria、Bacteroidetes和Actinobacteria为水体中优势类群。α-、γ-、δ-Proteobacteria,Actinobacteria及Bacteroidetes等菌群丰度随着水体的富营养化程度改变而有显著的变化。各湖区皆存在许多可能具有污染物降解及驱动生源要素循环能力的细菌类群。CCA分析表明TN、NH4+、NO3-和COD等水体指标对浮游细菌群落结构组成的影响较大。此外,乌梁素海水体内未知细菌类群很多;且不同于一般淡水生态系统,乌梁素海中存在9.6%的轻度嗜盐碱性细菌。【结论】乌梁素海水体中浮游细菌多样性较高,细菌群落结构复杂、其类群组成与富营养化因子紧密相关。     

湖泊细菌群落构建机制及其对富营养化的响应

细菌是湖泊生态系统的重要组成部分,在驱动湖泊生态系统元素物质循环和调控湖泊水质方面发挥关键性作用。揭示湖泊细菌群落多样性的形成和维持机制,即群落构建机制,是湖泊微生物生态学研究中的核心目标。近年来,微生物组学技术的发展,极大推动了湖泊细菌群落构建机制的研究。富营养化是当前我国湖泊生态系统面临的最大环境挑战之一,也是决定湖泊细菌群落组成和多样性的重要因素。研究综述了湖泊细菌群落构建机制的理论基础和发展脉络。概述了湖泊细菌群落构建机制的主要分析方法。总结了富营养化对湖泊细菌群落构建机制的影响的最新研究进展。针对富营养化影响下湖泊细菌群落构建机制研究所面临的问题,提出了未来的研究展望。     

不同寡营养培养条件下南海水体细菌群落结构及其对碳源的利用特征

【背景】绝大多数海洋微生物不可培养,为挖掘海洋生态系统中可培养的微生物资源,研究者尝试寡营养培养等方法。【目的】比较不同寡营养培养条件下南海水体细菌数量、群落结构及其对碳源的利用特征差异。【方法】采用原2216E培养液(Y)、稀释10倍(Y-10)和稀释50倍(Y-50)的2216E培养液培养南海海水样品,用荧光定量PCR法和16S rRNA基因检测细菌数量和菌群结构;利用平板计数法计数异养细菌的数量,纯化鉴定可培养细菌;采用Biolog EcoPlateTM微板法分析不同培养基中细菌群落对碳源的利用特征。【结果】Y组细菌总数高于Y-10组和Y-50组,差异不显著(P>0.05),但异养细菌数量显著高于Y-10组和Y-50组(P<0.05)。16S rRNA基因测序结果表明,不同稀释倍数下的细菌群落结构差异明显,Y组检测出10门193属,优势类群为Proteobacteria(56.44%)和Bacteroides (37.27%);Y-10组检测出15门220属,优势类群为Proteobacteria (40.30%)、Bacteroides(36.91%)和Firmic...     

水葫芦根际细菌群落结构多样性分析

【目的】了解水葫芦根际细菌群落结构。【方法】运用末端限制性片段长度多态性(Terminal restriction fragment length polymorphism,T-RFLP)技术分析富营养化水体中水葫芦根际和水葫芦近、远水样的细菌群落特征及多样性,结合克隆文库技术和培养法分析根际的细菌种群类型。【结果】同一时期水葫芦根际细菌多样性(Shannon-Weiner指数H′或Simpson指数D)更高,水葫芦近水样次之,远水样最小。10月份的细菌多样性高于5月份的。通过水葫芦根际细菌的克隆文库可知变形杆菌门(Proteobacteria)是水葫芦根际细菌的主要类群,占总群体的65.1%,包括噬菌弧菌(Bacteriovorax sp.)、Dechloromonas sp.、Leptothrix sp.、红螺菌科(Rhodospirillaceae)、Rhodoferax sp.和红环菌科(Rhodocyclaceae)等。T-RFLP图谱显示159 bp为最大优势菌,247 bp为第二大优势菌,对照克隆文库及培养结果分析247 bp属于γ-Proteobacteria,159 bp为不动杆菌(Acinetobacter sp.)。【结论】水葫芦根际细菌的群落结构丰富,不同时段水葫芦根际细菌的丰度略有变化,主要类群为变形杆菌门。     

崇测冰帽不同的冰川样品可培养细菌群落结构差异北大核心CSCD

【目的】研究细菌群落组成在西昆仑崇测冰帽冰川雪样、冰碛物和土样中的差异。【方法】通过传统的纯培养和菌株16S r RNA基因序列鉴定,分析菌株在门水平和属水平的群落结构。【结果】冰川细菌由Actinobacteria、Firmicutes、Proteobacteria和Bacteroidetes 4个门组成。雪样以Proteobacteria为优势,而土样和冰碛物则以Actinobacteria为优势。在属的水平上,冰川土样中的优势属仅有Arthrobacter,雪样中的优势属主要有Methylobacterium、Modestobacter、Hymenobacter、Brevundimonas、Bacillus这5种。雪环境的细菌群落结构与冰碛物和土样的差异性较大,而冰碛物和土样之间的差异性不大。Skermanella可能为崇测冰帽所特有的细菌。【结论】初步说明了在冰川退缩的气候环境下,冰川雪样细菌多样性的脆弱性,以及冰川雪环境细菌资源保护的重要性。     

海水富营养化对海洋细菌影响的研究进展

综述了海水富营养化对海洋细菌影响的研究进展。随着海水富营养化程度的增加,海洋细菌数量或生物量增加;反硝化细菌、大肠菌群尤其是厌氧性的硫酸盐还原菌和产甲烷菌等典型细菌生理群数量增加;浮游细菌群落结构随富营养化递增趋于简单,物种多样性降低;富营养化也明显导致细菌群落正常功能活性的紊乱。海水富营养化对细菌群落的结构和功能有着深远的影响。     

湖泊富营养化对轮虫群落结构及物种多样性的影响

2005年7月至2006年6月, 我们对安徽省芜湖市境内5个湖泊中轮虫的群落结构及部分水质特征参数进行了调查, 用相关加权综合营养状态指数(TLIc)评价了各湖泊的营养水平, 分析了其中的轮虫群落结构、多样性指数及其与TLI_C之间的关系。经鉴定, 5个湖泊中共采集到轮虫79种, 隶属18科31属; 不同营养水平湖泊中出现的轮虫种类数有明显的差异(P<0.01)。除龙窝湖外, 其余4个湖泊中的轮虫种类数与TLI_C均呈显著负相关关系(r＝–0.984, P<0.05)。湖泊水体的富营养化进程显著地提高了轮虫总密度和第一优势种的优势度, 降低了轮虫群落的均匀度和物种多样性指数。     

滴灌对苜蓿根际土壤细菌多样性和群落结构的影响

【背景】细菌作为土壤微生物中的重要类群,能够有效促进土壤物质循环和能量流动,细菌多样性以及群落结构能够反映土壤的质量状况。【目的】了解滴灌条件下苜蓿根际土壤细菌群落结构及多样性变化,探讨土壤环境因子对细菌群落结构的影响。【方法】基于细菌16Sr RNAV3-V4区高通量测序技术,分析比较滴灌与自然降雨两种模式下生长的苜蓿根际与非根际土壤中细菌多样性和群落分布规律,然后采用冗余分析(Redundancy analysis,RDA)探讨土壤环境因子与细菌多样性的关系。【结果】苜蓿根际土壤中细菌多样性丰富,滴灌根际土壤中细菌多样性显著高于自然降雨根际土壤;土壤样品中共检测到细菌46门53纲116目220科469属,主要的优势菌门为变形菌门(Proteobacteria,25.27%-34.42%),其中α-变形菌纲(Alphaproteobacteria,11.41%-18.97%)为优势亚群,鞘氨醇单胞菌属(Sphingomonas,1.00%-4.54%)为优势属。相较于自然降雨,滴灌条件下苜蓿根际土壤细菌的6个门和16个属的群落结构发生显著变化;此外,RDA分析表明,不同环境因子对微生物群落的影响不同,滴灌根际土壤中9个细菌属的丰度与全磷、全钾、有效磷、碱解氮、有机质、土壤中性磷酸酶以及土壤脲酶的含量显著正相关。【结论】滴灌作为新型节水技术,在促进植物生长、提高产量、节约成本的基础上增加了植物根际土壤中细菌多样性和丰度,该结果为新型灌溉体制的改革以及土壤微生物资源的开发利用提供科学数据。     

乌梁素海湖滨湿地细菌群落结构多样性

【目的】了解乌梁素海湖滨湿地水陆过渡带细菌群落结构及多样性变化,探讨富营养化湖泊湿地基质条件对细菌群落结构的影响。【方法】应用变性梯度凝胶电泳(PCR-DGGE)技术,分析和比较了依陆向分布的4个水陆过渡带样点的湿地细菌群落结构多样性,采用典型对应分析(CCA)探讨了湿地基质因子对细菌多样性的影响。【结果】DGGE图谱显示依湖泊水体沉积物(S-1)→湖滨芦苇沼泽沉积物(S-2)→湖滨碱蓬盐化草甸土壤(S-3)→岸上白刺荒漠土壤(S-4),4个样点的条带数依次减少,对应菌群结构及多样性变化显著;多样性指数分析结果显示,Shannon-Wiener指数(H)、均匀度(E)、丰富度(S)以及Simpson指数(DS)均显示依陆向分布逐步下降的规律,即:S-1S-2S-3S-4。序列比对结果显示,沉积物及土壤细菌分属于变形菌门(78.6%)、酸杆菌门(7.1%)、拟杆菌门(14.3%)这3个细菌类群,优势菌门为变形菌门,而变形菌门又分为5个亚群,其中ε变形菌纲为优势亚群;CCA结果表明,图中各条带对应物种的分布受铵态氮、总氮、有机碳、水溶盐总量、氯离子以及钾离子影响最大。【结论】乌梁素海富营养化湖泊的水陆过渡带湿地细菌群落结构存在较大差异,富营养化相关基质因子对细菌多样性影响较大。这为研究富营养化湖泊湿地水陆过渡带的细菌结构多样性及空间异质性提供了科学依据。     

Decomposition of water hyacinth detritus in eutrophic lake water

A study was conducted to determine the seasonal production of detritus by water hyacinths [Eichhornia crassipes (Mart.) Sohns] cultured in eutrophic Lake Apopka water, and the decomposition of detritus in situ and under laboratory conditions. Annual averages for C, N and P deposited through detritus production at the sediment-water interface were 2870, 176 and 19 kg ha^-1 yr^-1, respectively.Decomposition rates were faster in the root zone of hyacinth mats than at the sediment-water interface. Approximately 92% of the detritus C deposited at the sediment-water interface was decomposed in one year, while only 11% of the detrital organic N was mineralized. Detrital tissue gained P during decomposition, suggesting P limitation for the system. Dry-weight loss of detrital tissue was significantly correlated with the mass of C lost (r ² = 0.947^**), C/N ratio (r ² = 0.644^**) and C/P ratio (r ² = 0.428^**).Florida Agricultural Experiment Stations Journal Series No. R-00348.     

Bacterioplankton community structure in a eutrophic lake in relation to water chemistry

Bacteria are thought to be closely involved in the biogeochemical cycling of the nutrient elements in freshwater ecosystems. In contrast, little is known about the relationship between the bacterial community structure and the environmental factors. In order to investigate the spatial variety of bacteriplankton community structure in Lake Xuanwu (Nanjing, China) and the effects of water quality on the microbial community composition, denaturing gradient gel electrophoresis (DGGE) and multivariate statistical analysis were carried out. Eight major factors of water quality such as total organic carbon, ammonium, nitrate, nitrite, total nitrogen, total phosphorus, dissolved oxygen and pH were measured in eight different samples. The significant differences of water characteristics among different sites were revealed by principal component analysis. Results of multidimensional scaling analysis demonstrated that lake water quality played a crucial role in bacterioplankton community composition. Canonical correspondence analysis was carried out to infer the relationship between environmental variables and bacterial community structure. An influence of total nitrogen, ammonium and pH on the bacterial community was observed. The sequencing analysis results of excised DGGE bands revealed that Bacteroidetes and Proteobacteria were the dominant bacterial groups in Lake Xuanwu.     

基于富营养化水体修复的凤眼莲放养及采收条件研究

为实现富营养化水体的修复,对影响凤眼莲〔Eichhornia crassipes(Mart.)Sloms〕高产高效的放养及采收条件(包括初始放养日期、采收标准和采收比例)进行了研究,并对凤眼莲的生长曲线以及N、P和K的积累量进行了分析。实验结果表明:在总氮、总磷和钾含量分别为3.41~7.18、0.05~0.27和2.24~5.18 mg.L-1的水体中,在生长前期由于产生分蘖和植株个体生长,凤眼莲生物量快速增加;当植株生长至一定高度,生物量增幅减小;通过这一生长过程,凤眼莲的最高生物量可达28.28 kg.m-2。初始放养日期对凤眼莲的生长曲线和生物量均有明显影响,随初始放养日期的推迟生物量逐渐增大,在4月10日、4月17日、4月24日、5月1日和5月8日放养的凤眼莲经过63 d的放养,生物量均明显增加,其中,5月8日放养的凤眼莲总生物量最高,达到24.36 kg.m-2。采收标准和采收比例对凤眼莲的采收频率和累计采收量以及N、P和K积累量具有显著影响。按照10~15、15~20、20~25、25 kg.m-2以上及最高生物量的采收标准以及1/2和2/3的采收比例进行采收,凤眼莲的累计采收量均高于一次性采收(对照),且与其生物量呈抛物线型关系,但采收频率则与生物量成反比;采取不同的采收标准及采收比例,凤眼莲的干物质含量及N、P和K含量及总量均有一定的差异,但除干物质含量外,N、P和K含量及总量均明显高于一次性采收;总体上,采用20~25 kg.m-2的采收标准及2/3采收比例,凤眼莲的累计采收量最高、采收频率较少,对N、P和K的积累量最大。综合比较结果显示:在南京地区凤眼莲可于4月初开始放养,4月至5月分蘖,6月以后正常生长,并可按照20~25 kg.m-2的采收标准和2/3的采收比例进行采收。     

Influence of the habitat change for birds on community structure

In order to study the influence of habitat change on the community structure of birds, the species and individual numbers in the lakeside developmental land of Thousand-Island Lake have been recorded since January 2009 till December 2010, A fixed sample line was set up in the studied area, and the primary data was obtained about twice a month. In 2009, 1814 individuals were observed belonging to 12 orders, 31 families and 78 species, among which 4 species (Milvus lineatus, Haliastur Indus, Circus cyaneus and Glaucidium cuculoides) are the rank II national key protected species. In 2010, 872 individuals were recorded belonging to 12 orders, 33 families and 77 species, among which 2 species (Milvus lineatus and Glaucidium cuculoides) are the rank II national key protected ones. The total individual number of birds reduced 51.9%. Concerning the species, although the total species number decreased rarely after the habitat change, 23 species fled away and 22 species entered indicating the population similarity index value of 0.55. Among the top 10 species with large number of individuals, 5 species (Spizixos semitorques, Pycnonotus xanthorrhous, Paradoxornis webbianus, Passer montanus and Carduelis sinica) were overlapped indicating the similarity index value of 0.5. Comparison of the data of the corresponding months between two years, the highest similarity (index value > 0.6) was from January to February; and the lowest (index value < 0.3) from March to May. From June to December, the similarity index value was rebounded to 0.35–0.52 might due to the food tempt. Among the 55 overlapped species, 17 species (Tachybaptus ruficollis, Egretta garzetta, Phasianus colchicus, Streptopelia orientalis, Hirundo rustica, Hirundo daurica, Motacilla alba, Spizixos semitorques, Pycnonotus xanthorrhous, Pycnonotus sinensis, Urocissa erythrorhyncha, Paradoxornis webbianus, Prinia inornata, Passer rutilans, Passer montanus, Lonchura punctulata and Carduelis sinica) showed significant differences in individual number between the unchanged habitat and the changed habitat, including 2 species of water birds and 15 species of forest birds, which indicate these two types of birds were more affected than the others. In other words, the birds living close to the human crowds suffered bigger effect than the birds living away from the crowds. This is considered that the vocals, vehicle and machinery noises, and artificial constructions contributing to habitat change might be one of the main factors. All these analysis suggest the great influence of habitat change caused by human on the bird community structure. The higher diversity, richness and evenness index values in 2010 than in 2009 suggests that environmental modification led to a certain degree of habitat amelioration. Therefore, human being can improve environment by making the plant community structure complexity to increase the habitat heterogeneity, and consequently enhancing the diversity of bird community, as long as the habitat is not fragmented.     

用镶嵌组合植物群落控制湖泊饮用水源区藻类及氮污染

依据湖泊中不同生态类型水生高等植物的微生境特点,设计建造了由漂浮、浮叶、沉水植物为优势种的斑块小群丛构成的镶嵌组合水生植物群落（ＭｏｓａｉｃＣｏｍｍｕｎｉｔｙｏｆＭａｃｒｏｐｈｙｔｅｓ：ＭＣＭ）,并在太湖五里湖一湖湾内以动态模拟试验,从群落水平研究了水生高等植物群落对富营养化湖泊饮用水源区湖水的净化能力。结果表明,富营养化湖水经ＭＣＭ净化后,藻类生物量（以Ｃｈｌａ计）下降５７７％,藻类数量下降２～３个数量级,氨氮下降６６７％,总氮下降６００％,水质得到明显改善。与以该湖湾湖水为水源的水厂出水相比,经ＭＣＭ净化的湖水其氨氮比水厂出水的氨氮平均低４５１％,总氮低３７３％,可见经ＭＣＭ净化的湖水部分指标优于同源的自来水。综合群落的微生境特征及水生高等植物群落内硝化反硝化细菌分布特点,探讨了ＭＣＭ的除氮机理。     

Cd对土壤动物群落结构的影响

Cd污染对土壤动物影响的模拟实验结果表明,土壤动物群落结构的变化与Cd处理浓度的大小密切相关．在高浓度(99．48mg     

The effects of CO2 on sestonic stoichiometry and community structure of crustacean zooplankton in a eutrophic lake: Increased competitive ability of Bosmina

To explore the effects of CO₂ concentration on the sestonic stoichiometric values and the community structure of crustacean zooplankton in a eutrophic lake, in situ microcosm experiments were conducted at the Lake Taihu Ecosystem Station in spring and summer of 2012. The experimental treatments were three concentrations of CO₂, 270, 380 and 750 ppm, which represented preindustrial and present levels and the level predicted for the end of this century, respectively. The elevated atmospheric CO₂ concentration increased the sestonic C:P ratio, particularly in the spring when the C:P ratio was two-fold greater at the high level of CO₂ than at the low level of CO₂. As a result, the contribution of Bosmina to total crustacean zooplankton abundance increased, most likely because of the low phosphorus content and high adaptability to foods with large elemental ratio variation. The other dominant crustacean zooplankton genera, including Daphnia, Ceriodaphnia, Diaphanosoma and Sinocalanus, had no response to the change in pCO₂ during the microcosm experiments. The shift in crustacean zooplankton community structure between two seasons was primarily due to the transition of the phytoplankton community.     

环境因素对东平湖沉积物细菌群落结构的影响

【目的】探讨环境因素对东平湖沉积物细菌群落结构的影响。【方法】应用T-RFLP(Terminal RestrictionFragment Length Polymorphism)技术分析和比较了6个不同位置的东平湖沉积物在丰水期和枯水期的细菌多样性,并结合不同样品环境因子的差异,采用主成分分析(PCA)和典型对应分析(CCA),探讨了环境因子对细菌多样性的影响。【结果】不同沉积物样品的T-RFLP图谱具有较高的相似性。除2号样品外,所有枯水期样品的细菌群落具有较高的丰富度、多样性、均匀度和较低的优势度。CCA结果表明,558bp T-RF的丰度与总磷、总氮、总有机碳、铵态氮和硝态氮含量呈负相关而与碳氮比和水深呈正相关;64.5、164、509和543bp T-RFs的丰度与总氮、总有机碳、铵态氮、硝态氮、碳氮比和水深呈正相关;而其它14种主要的T-RFs在不同样品间分布较为稳定受环境因子影响不大。90、136.5、138和488bp等T-RFs可能代表了东平湖沉积物中占优势地位的土著菌群。通过Phylogenetic Assignment Tool在线分析结果推测,东平湖沉积物中的优势菌群可能属于Firmicutes和Proteobacteria门。【结论】环境因素对东平湖沉积物的细菌多样性产生显著影响,但对其土著菌群的影响不大。     

芜湖市镜湖轮虫群落结构分析及水质的生态学评价

2003年1—12月,对芜湖市镜湖轮虫群落结构的周年动态进行了研究,并分析了轮虫密度与有关生态因子间的关系。经鉴定,共发现轮虫55种,隶属于15科21属。密度优势种为裂痕龟纹轮虫(Anuraeopsis fissa)、暗小异尾轮虫(Trichocerca pusilla)、前额犀轮虫(Rhinoglena frontalis)、红多肢轮虫(Polyarthra remata)、长三肢轮虫(Filinia longise-ta)、广布多肢轮虫(Polyarthra vulgaris)和多须伪前翼轮虫(Proalides tentaculates),而生物量优势种为前节晶囊轮虫(Asplanchna priodonta)、多须伪前翼轮虫和暗小异尾轮虫。全年轮虫的总密度与水温、叶绿素a浓度及小型纤毛虫密度具有显著的相关性;温度对全年轮虫总密度的影响最大,叶绿素a浓度对春、冬季轮虫总密度影响最大,小型纤毛虫密度对夏季轮虫总密度影响最大,而水温是影响秋季轮虫总密度的主要因素。根据污染指示生物、物种多样性指数和Q值并结合水理化性质对治理后的镜湖水质所进行的初步评价表明,经清淤、截流和换水等措施治理后,小湖区应偏属寡污-β中污至β中污型水体,大湖区属于β中污型水体;目前镜湖水体处于中营养后期—富营养化初期阶段。       

再生水补水对河道底泥细菌群落结构的影响

以北京市永定河麻峪湿地再生水补水口附近河道底泥为研究对象,应用末端限制性片段长度多态性(Terminal Restriction Fragment Length Polymorphism,T-RFLP)技术探究再生水补水口附近底泥细菌群落结构的空间差异特征以及环境因子所产生的影响,并借助典范对应分析(Canonical Correspondence Analysis,CCA)方法分析麻峪湿地底泥细菌群落结构空间差异特征的形成原因。分析结果表明:河道底泥微生物群落对再生水的净化主要发生在距补水口1200m的范围内,随着再生水与上游来水径向混合净化渐变过程,在补水口2000m处河道底泥微生物群落结构与河道再生水补水口上游趋于相似。基于样点聚类结果的群落结构多样性分析表明随着再生水净化过程的实现微生物综合多样性指数呈现下降的趋势,从均匀度指数的变化趋势看,再生水补水口具有最高均匀度指数,补水口下游1200米处由于非优势菌群所占相对丰度最低以及偶见菌群缺失,导致群落结构比较单一、群落多样性和均匀度指数都最低。CCA方面分析结果表明再生水补水口上游细菌群落与因累积效应形成的重金属有密切关系,补水口出口底泥细菌群落则主要受到总磷和总有机碳的影响较大,而再生水补水与上游来水汇水径向渐变过程可能与氨氮净化具密切关系。研究区的主要优势菌种为假单胞菌属、贪食菌属和芽孢杆菌属,是与再生水中有机碳、氮降解具有密切关系的菌属。