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1.
为研究椒江化工园区邻近海域沉积物中细菌结构, 选取四个典型站点, 通过分离纯化、鉴 定和建立克隆文库的方法, 对其进行多样性及系统发育分析。可培养细菌的形态学及API 鉴定结果 显示洋葱假单胞菌及杀鲑气单胞菌杀鲑亚种是优势种, 典型细菌16S rDNA 分子鉴定结果表明厚壁 菌门及γ-变形菌纲为主要类群。非培养细菌克隆文库的序列分析结果表明: 细菌主要包括变形菌门、 酸杆菌门、绿弯菌门、芽单胞菌门、硝化螺旋菌门、CFB 群、放线菌门、厚壁菌门、浮霉菌门等9 个类群; 其中C3 站点克隆子主要属于γ-变形菌纲及δ-变形菌纲; C4 站点克隆子以γ-变形菌纲及酸杆 菌门为主; C5 站点克隆子主要属于δ-变形菌纲及γ-变形菌纲; C6 站点克隆子主要属于γ-变形菌纲及 放线菌门。综合可培养及非培养结果, 可发现椒江口化工园区邻近海域沉积物中γ-变形菌纲为典型 优势类群, 除相当数量的克隆子相似序列来自石油烃污染的沉积环境外, 还有大量克隆子相似序列 来自养殖污染环境。  相似文献   

2.
本研究通过构建16S r DNA克隆文库,对东海陆架五个站点的沉积物样品进行群落结构及地理分布研究。结果表明:东海陆架沉积物细菌分属于13个类群,包括变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、酸杆菌门(Acidobacteria)、绿弯菌门(Chloroflexi)、放线菌门(Actinobacteria)、硝化螺旋菌门(Nitrospira)、WS3、拟杆菌门(Bacteroidetes)、螺旋体门(Spirochaetes)、OP8、浮霉菌门(Planctomycetacia)、疣微菌门(Verrucomicrobiae)和芽单胞菌门(Gemmatimonadetes),其中变形菌门(γ-变形菌纲、δ-变形菌纲)和绿弯菌门为优势菌群,Latescibacteria(WS3)、疣微菌门和芽单胞菌门分别是站点DH6、DH21和DH9的特有类群。五个站点细菌多样性从高到低排序依次为DH9DH21DH17DH6DH16,其群落结构和丰度与各站点不同沉积环境类型有关。  相似文献   

3.
青岛、威海水域夏冬季表层沉积物细菌多样性的初步研究   总被引:4,自引:0,他引:4  
以青岛、威海水域夏冬两季表层沉积物中的基因组DNA为模板,扩增沉积物样品中细菌的16S rDNA 片段,并构建其相应文库.进行16S rDNA序列分析,并与数据库中的序列进行比对.分析结果表明:2个站位沉积物样品细菌分别属于11个主要细菌门类,包括:变形菌门(Proteobacteria)、浮霉菌门(Plancomycene)、芽单胞菌门(Gemmatimonadetes)、酸杆菌门(Acidobacteria)、硝化螺菌门(Nitrospirae)、疣微菌门(Verrucomicrobial)、拟杆菌门(Bacteroidetes)、绿屈挠菌门(Chloroflexi)、厚壁菌门(Firmicutes)、高G+C含量革兰氏阳性菌放线菌门(Actinobacteria)和低G+C含量革兰氏阳性菌梭菌门(Clostridiales).其中变形菌门是主要类群,且γ-变形菌纲(γ-Proteobacteria)占优势.与QD2站位相比,QD1站位沉积物细菌多样性随季节变化不大.  相似文献   

4.
为研究海洋附着细菌的群落结构及动态变化,在厦门近岸海区进行挂板实验.将无菌玻璃板浸没于海水中,连续放置14 d.分别于放置1 h和7、14 d后取玻璃板上附着生物样品.用细菌通用引物构建16S rRNA基因克隆文库,每个克隆文库随机挑选约40个克隆子测序,序列同源性分析和系统进化分析结果表明,所有的克隆子可分为六大类群:γ-变形菌纲(γ-Proteobacteria)、拟杆菌门(Bacteroidetes)、厚壁菌门(Firmicutes)、α-变形菌纲(α-Proteobacteria)、蓝细菌门(Cyanobacteria)和真核硅藻类叶绿体,各类群分别占42.0%、4.5%、2.2%、2.2%、1.1%和45.0%.γ-变形菌纲变形斑沙雷氏菌(Serratia proteamaculans)为优势附着细菌,占测序克隆子的31.5%.这类细菌在1 h样品中的比例超过一半,说明变形斑沙雷氏菌在生物膜形成初期发挥着重要作用.随着挂板时间延长,检测到的细菌类群有所增加:附着7 d后检测到拟杆菌门细菌,附着14 d后检测到厚壁菌门细菌.γ-变形菌纲细菌所占比例随挂板时间的延长而逐渐降低,从挂板1 h的81%降至7 d的21%,14 d的18%.另外,在各阶段的附着样品中,都检测到较多的真核克隆子序列,约占16%~64%.本研究为进一步阐明海洋附着细菌的附着动态及其在生物膜形成过程中的作用奠定了基础.  相似文献   

5.
长江口及邻近海域表层海水细菌多样性及群落结构   总被引:4,自引:0,他引:4  
从长江口及邻近海域10 个站点采集表层海水, 通过DAPI 染色计数和克隆文库构建的方法, 对细菌的多样性及群落结构进行初步研究。DAPI 染色计数结果显示长江口及邻近海域表层海水中 细菌丰度总体较高, 生物量变化较大, 从1.16×105(A04 站点)到 1.48×106 cells/mL (B03 站点); 总体 趋势从长江口向外海增加。细菌克隆文库的系统发育分析表明: 细菌序列以变形菌门为主(占总文库 的60.61%), 其中α-变形菌纲是绝对优势类群(50.62%); 其次是拟杆菌门(15.18%)、放线菌门(14.79%) 和蓝细菌门(4.61%), 还有少量厚壁菌门、绿弯菌门、酸杆菌门、浮霉菌门、纤维杆菌门、疣微菌门 等; 另外柔膜菌门和SAR 类群也有发现。文库多样性分析结果显示长江口及邻近海域部分站点表层 海水中细菌多样性显著, 与研究区海域水产养殖活动有关, 并受到区域洋流和海洋化学环境(如低氧 带)的影响。  相似文献   

6.
叶光斌  王风平  肖湘 《台湾海峡》2010,29(2):218-227
通过非培养手段研究了东太平洋中国多金属结核区ES0303站点锰结核样品中的微生物群落结构.细菌16S rRNA基因克隆文库的研究结果表明:结核内细菌种群结构复杂,微生物种类丰富且各种群丰度不一(61个OTUs),其中变形杆菌类群为优势种群,占所有细菌克隆子比例的64%,且主要分布于β/γ-、α-和δ-等3类变形杆菌(Proteobacteria)亚群之中,占比分别为34%、18%和12%.此外还存在包括酸杆菌(Acidobacteria),放线菌纲(Actinobacteria),绿弯菌门(Chloroflexi),厚壁菌门(Firmicutes),浮霉菌门(Planctomycetes)等在内的细菌类群的分布,克隆子比例依次为9%、7%、8%、2%和5%.古菌16S rRNA基因克隆文库的研究结果表明:古菌的群落结构单一(仅12个OTUs),全部是由泉古菌海洋类群I(crenarchaeote marine group I,MGI)组成;其中MGI-η类群最为丰富,达到44%,而MGI-α、MGI-ζ和MGI-ε类群的克隆子比例分别为25%、18%和9%,另外还发现2个新的MGI分类类群.相关克隆子的数据库比对和系统发育树分析表明,并未发现已报道的直接参与铁锰氧化还原相关类群的存在,但它们大多数与来自多金属结核来源或深海来源的不可培养微生物具有较高的同源性.进一步的分析表明,锰结核内存在相当数量的氨氧化菌、硫酸盐还原菌、酸杆菌等能够改变pH值的细菌和古菌类群的存在,意味着它们可能在锰结核的形成过程中起到重要的作用.  相似文献   

7.
从枸杞岛海藻场和对照点贻贝场分别采取表层及底层水样,利用细菌通用引物,提取样品总DNA进行聚合酶链式反应(PCR)扩增,采用16SrDNA文库技术,对其细菌群落进行鉴定和分析。结果表明,海藻场表层和底层细菌群落分为5和6个门,贻贝场表层和底层细菌群落分为3和4个门,海藻场中细菌分类门数多于贻贝场内,优势菌均为变形细菌门,分别占克隆文库的比例为40.7%、50%、59.1%和48.1%。γ-变形菌纲为变形细菌门的优势亚群,各个文库中均含有许多未确定其分类的序列,即含有许多未被认知的微生物类群。变形菌门、厚壁菌门和放线菌门为所有水样共有,但在水层垂直分布及不同地理位置间存在较大差异。不同功能类群可能与其特殊生境密切相关。  相似文献   

8.
南海北部巴士海峡深海沉积物中细菌多样性分析   总被引:2,自引:1,他引:1       下载免费PDF全文
从南海北部巴士海峡深海沉积物中提取到高质量的总DNA, 通过TA克隆构建了含有23个可操作分类单元(OTU)的16S rRNA基因文库, 选择各OTU中代表性克隆子进行测序与系统发育分析, 结果表明, 南海北部巴士海峡深海沉积物中细菌在系统进化树中至少分属于9个类群: 其中放线菌Actinobacteria, 变形细菌Proteobacteria, 和浮霉菌Planctomycetes为优势种;其他细菌如疣微菌Verrucomicrobia, 鞘脂杆菌Sphingobacteria, 硝化螺旋菌门(Nitrospira), 绿弯菌Chloroflexi, 厚壁菌Firmicute, 酸杆菌Acidobacteria等为非优势种群;另外有两个克隆子属于未知种群.在所获得的23个代表克隆子序列中,有11个序列与已知细菌的同源性≤95%, 占到了所有序列的48%, 这一结果说明在南海北部巴士海峡海区具有非常丰富的微生物多样性, 这一海区蕴含着大量未知的微生物资源, 因而值得进行进一步的研究探索.  相似文献   

9.
研究海水环境中Q235碳钢锈层中微生物群落的多样性。应用16SrDNA基因文库技术,分别对实海全浸一年的Q235碳钢内外锈层中的微生物进行基因文库的构建和分析。通过克隆测序构建了含有64个OTUs的细菌16SrRNA基因文库,结果表明锈层中微生物种类丰富,主要分布于13个已知的菌门,包括变形菌门;拟杆菌门;硅藻门;酸杆菌门;浮霉菌门;硝化螺旋菌门;厚壁菌门;绿弯菌门;疣微菌门;绿菌门;放线菌门;红藻门以及螺旋体门。内外锈层的优势菌均为变形细菌门,分别占文库序列的46%和53%,其中α-变形菌纲又为门中优势类群,但在内外锈层中还存在明显的系统发育学分歧。  相似文献   

10.
为研究南太平洋环流区底层海水可培养细菌的多样性,通过IODP 329航次获得了该区域7个站点的底层海水样品,利用传统的分离培养法获得菌株后,进行16SrDNA测序及系统发生分析。结果表明,从南太平洋环流区7个站点的底层水中分离出174株深海细菌,这些菌株属于4个门,30个属,78个种。其中γ-变形菌纲(γ-Proteobacteria)有143株,在数量和种类方面均占主导地位;α-变形菌纲(α-Proteobacteria)7株,β-变形菌纲(β-Proteobacteria)2株,厚壁菌门(Firmicutes)11株,放线菌门(Actinobacteria)6株,拟杆菌门(Bacteroidetes)5株。优势属有假交替单胞菌属(Pseudoalteromonas)、交替单胞菌属(Alteromonas)、弧菌属(Vibrio)、盐单胞菌属(Halomonas)等10个属;优势种有居珊瑚假交替单胞杆菌(Pseudoalteromonas paragorgicola)、子午盐单胞菌(Halomonas meridiana)、坎氏弧菌(Vibrio campbellii)、西班牙交替单胞菌(Alteromonas hispanica)、河豚毒素假交替单胞菌(Pseudoalteromonas tetraodonis)、琼氏不动杆菌(Acinetobacter junii)等12个。在7个站点中,位于环流边缘的U1371站点分离出的菌株数量明显多于其他站点,且是7个站点中唯一1个包含了分离出的所有6个门类的站点,多样性最高;而U1369和U1370站点都只分离出γ-变形菌纲1个门类。此外,9株细菌可能为海洋细菌新属或新种。  相似文献   

11.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

12.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   

13.
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.  相似文献   

14.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

15.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.  相似文献   

16.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

17.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

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《海洋学报(英文版)》2014,(11):161-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

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