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1.
随着有机氟化物在各领域的广泛应用,含氟有机废水处理面临巨大挑战。活性污泥作为有机废水处理的核心技术之一,微生物在其中发挥着极其重要的作用。本综述首先聚焦在活性污泥微生物群落多样性、组成、结构和功能及其与含氟废水类型、处理工艺和处理效率之间的关系,进而讨论了功能微生物降解/转化有机氟化物的途径和作用机制,最后展望了结合分离培养降解有机氟化物的关键微生物,以及微生物组学技术解析活性污泥微生物群落构建、互作、代谢等核心问题,以提高对含氟有机废水微生物降解机理的认识,优化含氟有机废水处理工艺。  相似文献   

2.
土壤微生物是土壤养分循环的关键驱动者,对土壤环境变化感应明显,氮是陆地生态系统的限制元素之一,其改变可能会给生态系统物种多样性造成一定影响.为了解高寒湿地土壤微生物组成对氮添加的响应,以青海湖流域高寒湿地为研究对象,通过(0 g·m-2、0.5 g·m-2、1 g·m-2、1.5 g·m-2、2 g·m-2、2.5 g...  相似文献   

3.
Terminal restriction fragment length polymorphism (T-RFLP) analysis is commonly used for profiling microbial communities in various environments. However, it may suffer from biases during the analytic process. This study addressed the potential of T-RFLP profiles (1) to reflect real community structures and diversities, as well as (2) to reliably detect changing components of microbial community structures. For this purpose, defined artificial communities of 30 SSU rRNA gene clones, derived from nine bacterial phyla, were used. PCR amplification efficiency was one primary bias with a maximum variability factor of 3.5 among clones. PCR downstream analyses such as enzymatic restriction and capillary electrophoresis introduced a maximum bias factor of 4 to terminal restriction fragment (T-RF) signal intensities, resulting in a total maximum bias factor of 14 in the final T-RFLP profiles. In addition, the quotient between amplification efficiency and T-RF size allowed predicting T-RF abundances in the profiles with high accuracy. Although these biases impaired detection of real community structures, the relative changes in structures and diversities were reliably reflected in the T-RFLP profiles. These data support the suitability of T-RFLP profiling for monitoring effects on microbial communities.  相似文献   

4.
定殖于鼻咽部的微生物与人体始终处于动态生态平衡,对于维持人体健康发挥着重要作用,也与多种上呼吸道疾病的发生发展有密切关系。鼻咽部微生物之间及其与宿主之间的相互作用是引发人体上呼吸道疾病的重要因素。微生物的培养方法与分子生物学技术的结合使人们越来越深入地了解人体鼻咽部微生物群落的组成和结构。定殖于人体鼻咽部的微生物以肺炎链球菌(Streptococcus pneumoniae)和流感嗜血杆菌(Haemophilus influenzae)等潜在致病菌为主。本文将分别从鼻咽部微生物与机体的平衡关系、鼻咽部微生物群落的研究方法以及鼻咽部微生物群落的组成及其相互关系三个方面,综述近年来鼻咽部微生物群落结构的相关研究进展,从而为指导实践提供可靠的理论依据。  相似文献   

5.
【目的】随着中国奶牛业的发展,干草需求量与日俱增。作为天然牧草,干草可以成为家畜传播病原体的载体。以干草表面附着物为研究对象,了解干草中细菌群落结构以及致病菌属特征。【方法】对来自6个不同奶牛场饲草舍的干草样本,应用Illumina Mi Seq高通量测序技术测定干草表面附着物细菌的16S r RNA基因V3-V4变异区序列,分析不同干草样本细菌群落组成。【结果】干草样本中的细菌在97%的相似水平下共得到OTU个数为15 416,涵盖了29门87纲144目219科323属的细菌。微生物多样性分析表明,干草样本具有很高的细菌多样性,不同样本多样性存在差异。对干草样本菌群中丰度较高的14种病原菌属进行分析,发现相较于人工种植牧草制备的干草,天然牧草制备的干草中病原菌属丰度较高。【结论】研究解析了干草样本中微生物的多样性、丰度及主要病原菌属的特征,对奶牛场疾病防控有一定指导意义。  相似文献   

6.
Yang Q  Zhang W  Zhang H  Li Y  Li C 《Bioresource technology》2011,102(4):3790-3798
In this study, an alkali bacterial consortium was obtained by enrichment cultivation and was used to treat printing and dyeing wastewater (PDW, pH 11-12). The treatment effects and dynamic changes were evaluated in a biocontact oxidation reactor (BOR) and a sequencing batch reactor (SBR). During 3 months of continuous operation, the two bioreactors had similar treatment efficiencies (polyvinyl alcohol, PVA, 74.5-81.3%; COD, 73.5-77.4%; 2.15 pH decreases). Molecular biological analysis indicated that the microbial communities underwent dramatic changes during the operation, in which the SBR was superior to the BOR in retaining the alkali bacteria at the start-up stage, however, the BOR seemed to be more advantageous when the frequently changing influents were considered. The bacterial communities in BOR and SBR were diverse and included Bacteroidetes, Firmicutes, Proteobacteria, Actinobacteria and an unidentified cluster. Among these only Paracoccus sp. was successfully isolated and confirmed to have the ability to degrade PVA.  相似文献   

7.
To better understand how cathode performance and substrates affected communities that evolved in these reactors over long periods of time, microbial fuel cells were operated for more than 1 year with individual endproducts of lignocellulose fermentation (acetic acid, formic acid, lactic acid, succinic acid, or ethanol). Large variations in reactor performance were primarily due to the specific substrates, with power densities ranging from 835 ± 21 to 62 ± 1 mW/m3. Cathodes performance degraded over time, as shown by an increase in power of up to 26% when the cathode biofilm was removed, and 118% using new cathodes. Communities that developed on the anodes included exoelectrogenic families, such as Rhodobacteraceae, Geobacteraceae, and Peptococcaceae, with the Deltaproteobacteria dominating most reactors. Pelobacter propionicus was the predominant member in reactors fed acetic acid, and it was abundant in several other MFCs. These results provide valuable insights into the effects of long-term MFC operation on reactor performance.  相似文献   

8.
不同森林恢复类型对土壤微生物群落的影响   总被引:42,自引:4,他引:42  
为了评价不同森林恢复类型与方式对南方红壤丘陵区退化生态系统土壤微生物群落的影响,借助氯仿熏蒸法、平板涂抹法和BIOLOG检测法,比较研究了4种森林恢复类型土壤微生物的群落特征.结果表明,4种森林恢复类型土壤微生物生物量碳、细菌数量差异显著,2项指标均以天然次生林土壤最高,人工林次之,荒地最差;碳源平均颜色变化率(AWCD法)和微生物代谢多样性指数(丰富度和多样性)在5种植被类型的土壤中也有明显差异,其趋势与微生物量碳、细菌数量基本相同;天然次生林土壤微生物群落利用碳源的整体能力和功能多样性比人工林和荒地强.相关分析表明,0~20和20~40cm土壤微生物的代谢多样性与根系生物量紧密相关(r=0.933,P<0.05;r=0.925,P<0.05).自然恢复更有利于改善土壤微生物的结构和功能.  相似文献   

9.
The Orlando Easterly Wetland (OEW), located near Christmas, Florida, USA, is among the longer-lived treatment wetlands in the United States. It was established in the late 1980s to reduce nitrogen and phosphorus concentrations from tertiary treated wastewater bound for the St. Johns River. A goal of 0.07 mg/l total phosphorus concentration has been set by the regulating agency (St. Johns River Water Management District). In order to understand and define the operating conditions for which this target could be met, a systematic study of historic phosphorus uptake was performed using a traditional first-order model. Phosphorus uptake performance is shown to correlate well with hydraulic performance for two parallel upstream cells. The first-order model is enhanced with predictive capabilities that acknowledge the correlation between the phosphorus uptake rate constant and the hydraulic loading rate observed in the system. Inherent limitations with the first-order modeling approach are addressed and uncertainty in model performance is used to bound predictions.  相似文献   

10.
Natural ecosystems provide services to agriculture such as pest control, soil nutrients, and key microbial components. These services and others in turn provide essential elements that fuel biomass productivity. Responsible agricultural management and conservation of natural habitats can enhance these ecosystem services. Vineyards are currently driving land‐use changes in many Mediterranean ecosystems. These land‐use changes could have important effects on the supporting ecosystems services related to the soil properties and the microbial communities associated with forests and vineyard soils. Here, we explore soil bacterial and fungal communities present in sclerophyllous forests and organic vineyards from three different wine growing areas in central Chile. We employed terminal restriction fragment length polymorphisms (T‐RFLP) to describe the soil microbial communities inhabiting native forests and vineyards in central Chile. We found that the bacterial community changed between the sampled growing areas; however, the fungal community did not differ. At the local scale, our findings show that fungal communities differed between habitats because fungi species might be more sensitive to land‐use change compared to bacterial species, as bacterial communities did not change between forests and vineyards. We discuss these findings based on the sensitivity of microbial communities to soil properties and land‐use change. Finally, we focus our conclusions on the importance of naturally derived ecosystem services to vineyards.  相似文献   

11.
若尔盖高寒湿地干湿土壤条件下微生物群落结构特征   总被引:14,自引:4,他引:14  
牛佳  周小奇  蒋娜  王艳芬 《生态学报》2011,31(2):474-482
土壤水分含量的空间异质性是引起湿地生态系统结构和功能空间变异的关键因素。目前有关低纬度高寒湿地土壤水分对微生物群落结构影响的研究较少。于2007年4月(冷季)和8月(暖季)采集若尔盖高寒湿地常年淹水和无淹水两种水分条件的土壤样品,利用磷脂脂肪酸方法分析其微生物群落结构。结果表明,土壤微生物总生物量、细菌生物量、革兰氏阳性细菌及革兰氏阴性细菌生物量均表现为常年淹水土壤高于无淹水土壤,且4月份高于8月份;与土壤通气量关系密切的真菌、放线菌,其生物量表现为无淹水土壤显著高于常年淹水土壤;反映群落组成的真菌:细菌磷脂脂肪酸比值也表现为无淹水土壤显著高于常年淹水土壤。磷脂脂肪酸的主成分分析表明,水分条件不同的两种土壤中微生物群落结构显著不同,季节变化并未引起土壤微生物群落结构的改变。  相似文献   

12.
Permafrost represents an important understudied genetic resource. Soil microorganisms play important roles in regulating biogeochemical cycles and maintaining ecosystem function. However, our knowledge of patterns and drivers of permafrost microbial communities is limited over broad geographic scales. Using high‐throughput Illumina sequencing, this study compared soil bacterial, archaeal and fungal communities between the active and permafrost layers on the Tibetan Plateau. Our results indicated that microbial alpha diversity was significantly higher in the active layer than in the permafrost layer with the exception of fungal Shannon–Wiener index and Simpson's diversity index, and microbial community structures were significantly different between the two layers. Our results also revealed that environmental factors such as soil fertility (soil organic carbon, dissolved organic carbon and total nitrogen contents) were the primary drivers of the beta diversity of bacterial, archaeal and fungal communities in the active layer. In contrast, environmental variables such as the mean annual precipitation and total phosphorus played dominant roles in driving the microbial beta diversity in the permafrost layer. Spatial distance was important for predicting the bacterial and archaeal beta diversity in both the active and permafrost layers, but not for fungal communities. Collectively, these results demonstrated different driving factors of microbial beta diversity between the active layer and permafrost layer, implying that the drivers of the microbial beta diversity observed in the active layer cannot be used to predict the biogeographic patterns of the microbial beta diversity in the permafrost layer.  相似文献   

13.
本文系统调查了武汉市解放公园和月湖公园人工湿地区不同季节、不同植物类群昆虫群落多样性,共采集昆虫标本7313头,隶属于13目、81科、198种。群落特征研究结果显示9月为昆虫多样性最高的月份,Shan-non-Wiener指数分别为解放公园4.7949,月湖公园4.4611;昆虫群落的季节变化情况是温度升高,多样性指数升高,但温度过高会抑制昆虫多样性;不同植物种类间昆虫多样性差别很大,种类极不相似,昆虫群落多样性最高的植物群落是千屈菜。  相似文献   

14.
Three soil DNA extraction procedures (homemade protocols and commercial kit) varying in their practicability were applied to contrasting soils to evaluate their efficiency in recovering: (i) soil DNA and (ii) bacterial diversity estimated by 16S rDNA pyrosequencing. Significant differences in DNA yield were systematically observed between tested procedures. For certain soils, 10 times more DNA was recovered with one protocol than with the others. About 15 000 sequences of 16S rDNA were obtained for each sample which were clustered to draw rarefaction curves. These curves, as well as the PCA ordination of community composition based on OTU clustering, did not reveal any significant difference between procedures. Nevertheless, significant differences between procedures were highlighted by the taxonomic identification of sequences obtained at the phylum to genus levels. Depending on the soil, differences in the number of genera detected ranged from 1% to 26% between the most and least efficient procedures, mainly due to a poorer capacity to recover populations belonging to Actinobacteria, Firmicutes or Crenarchaeota. This study enabled us to rank the relative efficiencies of protocols for their recovery of soil molecular microbial biomass and bacterial diversity and to help choosing an appropriate soil DNA extraction procedure adapted to novel sequencing technologies.  相似文献   

15.
Power densities produced by microbial fuel cells (MFCs) in natural systems are changed by exposure to light through the enrichment of photosynthetic microorganisms. When MFCs with brush anodes were exposed to light (4000 lx), power densities increased by 8–10% for glucose-fed reactors, and 34% for acetate-fed reactors. Denaturing gradient gel electrophoresis (DGGE) profiles based on the 16S rRNA gene showed that exposure to high light levels changed the microbial communities on the anodes. Based on 16S rRNA gene clone libraries of light-exposed systems the anode communities using glucose were also significantly different than those fed acetate. Dominant bacteria that are known exoelectrogens were identified in the anode biofilm, including a purple nonsulfur (PNS) photosynthetic bacterium, Rhodopseudomonas palustris, and a dissimilatory iron-reducing bacterium, Geobacter sulfurreducens. Pure culture tests confirmed that PNS photosynthetic bacteria increased power production when exposed to high light intensities (4000 lx). These results demonstrate that power production and community composition are affected by light conditions as well as electron donors in single-chamber air-cathode MFCs.  相似文献   

16.
模拟油藏条件下内源微生物群落空间分布规律   总被引:3,自引:0,他引:3  
【背景】油藏内源微生物群落是开展内源微生物驱油技术的物质基础,由于油藏多孔介质取样技术难度大、成本高,实施内源微生物驱油后从注入端到产出端多孔介质中的内源微生物空间分布规律尚不明确。【目的】通过室内长岩心连续驱替实验模拟油藏内源微生物驱油过程,分析实施后不同空间位点油砂上吸附的内源微生物群落结构,揭示从注入端到产出端内源微生物群落的空间分布规律。【方法】借助高通量测序技术及荧光定量PCR技术解析不同空间位点油砂原位微生物群落信息。【结果】注入端到产出端不同空间位点生态环境的差异及菌属间的相互作用造成油藏内源微生物群落空间分布差异,存在明显的好氧、厌氧空间演替变化规律。岩心前端主要存在一些好氧类的产生物表面活性剂类微生物如假单胞菌属,岩心中部主要存在兼性和厌氧类的微生物如地芽孢杆菌、厌氧杆菌属,岩心末端主要分布严格厌氧类细菌和产甲烷古菌,厌氧类微生物代谢产生的H2、CO2和乙酸分子可以为产甲烷古菌提供代谢底物。【结论】通过室内物模油砂研究,首次明确了内源微生物群落在多孔介质中从注入端到产出端的空间分布规律,证实油藏内源微生物的好氧、厌氧空间接替分布规律,深化了对油藏内源微生物的认识。  相似文献   

17.
促淤等人为扰动对长江口滩涂湿地土壤微生物呼吸的影响   总被引:1,自引:0,他引:1  
为阐明促淤和堤内农业生产对长江口滩涂湿地土壤微生物呼吸(SMR)的影响,在崇明东滩和九段沙湿地设置3个典型区域,研究了人为扰动和自然状况下湿地SMR的差异性,并通过分析不同类型湿地土壤的微生物活性和环境因子阐明了导致SMR差异的主要原因。结果显示,促淤区现有湿地SMR强度((0.41±0.22)mgCO·2g-·124h-1)高于自然状态区((0.07±0.02)mgCO·2g-·124h-1),且差异达到了极显著水平(P0.01);堤内不同农业生产模式导致的施肥强度差异对堤外湿地SMR也有一定影响。通径分析表明,促淤等人为扰动状态下湿地土壤微生物活性增强是导致其SMR较高的主要原因,其中土壤原核微生物多样性指数及蔗糖酶活性与SMR强度的关联性尤为显著。而促淤与堤内化肥施用所引起的已有滩涂湿地土壤环境条件的改变,特别是土壤含水量下降和无机氮含量增高是导致其微生物活性发生改变的重要原因。总体而言,促淤和堤内高强度施肥的农业生产模式一定程度上会增强堤外现有滩涂湿地的SMR,从而弱化其碳汇功能。  相似文献   

18.
Constructed wetlands (CWs) have received increasing attentions for their N removal performances, especially regarding NH4+-N. Different influent NH4+-N concentration may influence N removal efficiency in practice, while the effects of different NH4+-N concentrations on microorganisms removing N in CWs are poorly understood. In this study, surface flow CWs planted with Myriophyllum (M). aquaticum were established to investigate the influences of different NH4+-N concentrations on the composition, structure, and interactions of microbial community. Our findings suggested 105 mg/L NH4+-N CWs achieved highest N removal rate, removing 89.30 % NH4+-N and 92.34 % TN from the influent. The results of real-time quantitative polymerase chain reactions (qPCR) indicated abundances of nitrifying genes (nxrA) and denitrifying genes (narG, nirS, nirK, and nosZ) were increased by increasing NH4+-N concentrations, and the strongest effects were observed in narG (8-fold) and nosZ genes (11-fold). Different NH4+-N concentrations was proved to alter composition and structure of microbial communities via high-throughput sequencing, e.g. denitrifiers including Brevendomonas.sp, Dokdonella.sp and Rhodococcus.sp were enriched obviously with increasing NH4+-N concentrations. In addition, network showed interactions among microbial populations and positive interactions were dramatically shifted and enhanced by increasing NH4+-N concentrations.  相似文献   

19.
南京近郊自然湿地维管植物群落特征   总被引:5,自引:0,他引:5  
选择南京近郊2处自然湿地为研究对象,采用GPS定位、野外标本采集、Braun-Blanquet多盖度等级法和Shannon-Wiener物种多样性、Simpson生态优势度和群落均匀度指数研究南京湿地植物群落的种类组成、群落类型及其数量特征。结果表明南京湿地有维管植物104种,隶属于93属45科,其中有国家Ⅱ级保护植物4种,包括水蕨、野大豆、野菱和莲;属和种的地理成分分析表明,该区维管植物区系以温带成分为主,同时热带成分也占一定的比例;该区湿地植被分为3个植被型,3个植被亚型,16个群系;湿地植物群落的物种多样性指数偏低,其中七里河湿地的物种多样性高于滁河入江口。根据南京湿地维管植物群落的特征,并结合当前存在的问题,提出南京近郊自然湿地的保护对策。  相似文献   

20.
土壤微生物是生态系统维持正常结构与功能的重要组成部分,为探究盐城滩涂典型湿地土壤微生物群落结构特征,以江苏盐城滩涂互花米草、藨草、盐地碱蓬、芦苇及淤泥质光滩5种典型群落为对象,采用16S rRNA高通量测序技术分析0—10 cm(表层)、10—30 cm(中层)、30—60 cm(深层)土壤微生物多样性及群落结构。结果表明:(1)几种植物群落间,土壤微生物群落结构差异较大,主要体现在细菌群落结构的差异性,古菌群落结构差异相对较小。光滩与植物群落间,在土壤细菌种类及相对丰度上差异相对较大,互花米草群落与本土植物群落间,在微生物群落的细菌种类组成上存在较大差异;藨草群落土壤表层微生物群落结构与互花米草群落相似,深层与盐地碱蓬、芦苇群落相似。(2)同一群落不同层次土壤微生物群落结构相似,差异小于不同群落间土壤微生物群落的结构差异性;不同群落对应层次间,表深层土壤中五种群落土壤微生物多样性存在显著差异,中层土壤中五种群落微生物多样性差异不显著。总体上,植物群落类型对土壤微生物群落结构的影响大于土壤深度;与本土植物群落相比,互花米草群落土壤主要优势门微生物种类差异较小,但部分优势门微生物相对丰度...  相似文献   

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