Microbial carbonates: the geological record of calcified bacterial–algal mats and biofilms     

Robert Riding 《Sedimentology》2000,47(S1):179-214

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海泥中硫酸盐还原菌数量变化对主要腐蚀环境因子的影响   总被引：1，自引：1，他引：1  

朱永艳  郑传波  李言涛  黄彦良 《海洋科学》2006,30(11):37-40

海泥中硫酸盐还原菌(SulfateReducingBacteria,SRB)数量的变化会对其主要腐蚀环境因子产生影响。实验室条件下,在灭菌青岛海泥中加SRB菌种得到含SRB的海泥。在SRB的一个生长周期内,测量了由SRB数量变化引起的硫电位、银电位、pH值、氧化还原电位及电导率等主要腐蚀环境因子的变化,并找出了该变化的规律,探讨了通过腐蚀环境因子的变化测量SRB数量的可能性。  相似文献   

Foraminiferal selectivity towards bacteria: an experimental approach using a cell-permeant stain     

A.M. Langezaal  N.T. Jannink  E.S. Pierson  G.J. van der Zwaan   《Journal of Sea Research》2005,54(4):25

The behaviour of two species of foraminifera (Allogromia laticollaris and Ammonia beccarii) towards living and dead bacteria and inorganic particles was monitored using a cell-permeant fluorescent nucleic acid stain. The foraminifera were studied in seawater containing fluorescently labelled dead and living bacteria, and/or polystyrene particles of the same size as a control. Time-lapse observations under a fluorescence microscope clearly revealed pseudopodial transport of stained bacteria and uptake of bacteria inside the foraminifera. In contrast, no uptake of polystyrene particles was ever observed, although the foraminifera collected these particles and deposited them along the outside of the test. We conclude that foraminifera distinguish food and non-food particles while collecting. There appears to be a variation of uptake rate and final amount of ingested and digested bacteria. These variations occur between individuals of different size and species, and between sampling times (September 2001 and July 2002).  相似文献   

Chemical and Biological Studies of Particulate Organic Matter in the Ocean     

John K. Volkman  Eiichiro Tanoue 《Journal of Oceanography》2002,58(2):265-279

This paper presents a review of the past decade's highlights of research on the isolation and characterisation of particulate organic matter (POM) in the world's oceans. The emphasis is on chemical studies but, in keeping with the growing interdisciplinary nature of marine science, advances in other disciplines are also discussed, particularly those in biological sciences. Increasing evidence for the importance of picoplankton, bacteria and viruses as POM constituents is highlighted, including the recent recognition of large populations of autotrophic bacteria able to harvest light for energy. The transport of POM to bottom waters was thought to be largely confined to large, rapidly sinking faecal pellets. However, recent studies have highlighted the importance of organic aggregates and flocs formed by diatoms such as Rhizosolenia and other microalgae. Ascending particles have also been discovered, many of which are lipid-rich. Several studies have shown that resuspension of bottom sediments and lateral advection of material from continental shelves can lead to anomalously high particle fluxes measured in sediment traps moored in deep water. Many new approaches for characterizing POM have emerged, such as pyrolysis gas chromatography-mass spectrometry and direct temperature-resolved mass spectrometry for analysis of higher molecular weight materials and biopolymers. Lipid biomarker techniques have also advanced, exciting new possibilities being raised by the ability to measure stable and radioactive carbon isotopes for individual compounds. The techniques of molecular biology, such as the polymerase chain reaction (PCR), are being increasingly applied to provide complementary information to more conventional microscopy and flow cytometry on the identity of organisms in the sea. The combination of these techniques with advanced chemical analysis methods promises to greatly increase our knowledge of the origins, transport and fate of organic matter in the oceans. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Amino Sugars and Their Indicating Role in the Cycling of Organic Matter in Marine Environment     

Ren Chengzhe  Yuan Huamao  Song Jinming  Li Xuegang  Li Ning  Duan Liqin 《地球科学进展》2017,32(9):959-971

As a kind of marine organic matter with important geochemical characteristics, amino sugars can effectively reflect the source, diagenetic state and mineralization process of organic matter by their concentration and composition in marine environment. This article systematically concluded the research progresses of amino sugars from the aspects of their source, composition and distribution characteristics in marine environment, and the role as a biomarker indicating source and diagenetic state of marine organic matter. The result showed that the macromolecular morphology, the oxygen and nutrient level and the sedimentary environment could affect the reactivity of amino sugars. The higher ratios of glucosamine to galactosamine (GlcN/GalN) and the Total Hydrolysable Amino Acids to Total Hydrolysable Amino Sugars (THAA/THAS) can reflect the fresh planktonic organic matter source and the lower ratios can reflect the conversion from planktonic to bacterial organic matter. The carbon and nitrogen normalized yield of total hydrolysable amino sugars, however, could give contradictory results depending on the relative contribution of the source and degradation degree of organic matter. Muramic acid is suitable to estimate the contribution of relatively fresh bacteria organic matter to particulate and sediment organic matter, but it is not suitable for applying in the dissolved organic matter because of its very low concentration leading from its rapid recycle. It is critical to enhance the research on the contribution of different microorganisms to amino sugars and differentiate the influence of organic matter source and degradation on amino sugars in marine environment. The research on the conversion and fate of amino sugars in marine environment is also needed.  相似文献   

Effect of Different Nanomaterials on the Metabolic Activity and Bacterial Flora of Activated Sludge Medium          下载免费PDF全文

Tülay Ergön‐Can  Derya Y. Köseoğlu‐İmer  Ömer Faruk Algur  İsmail Koyuncu 《洁净——土壤、空气、水》2016,44(11):1508-1515

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A new bioassay for the inspection and identification of TBT-containing antifouling paint     

Herv Gueun  Grald Thouand  Marie-Jos Durand 《Marine pollution bulletin》2009,58(11):1734-1738

Since the 1960s tributyl (TBT)-based antifouling paints are widely applied to protect ship’s hulls from biofouling. Due to its high toxicity to aquatic ecosystem most of the countries (28 nations in 2008) signed the AFS convention to control the use of harmful antifouling systems on ships. Nevertheless there is currently no simple method to control the presence of organotin in paint. In this study, we propose a bioassay based on the use of a recombinant bioluminescent bacteria to detect directly in paint the presence of TBT. We also propose a simple device as an inspection system to control the absence of organotin in the ship’s hull paint. The presence of organotin could be revealed in less than three hours.  相似文献   

Effect of Sludge Retention Time on Nitrifiers' Biomass and Kinetics in an Anaerobic/Oxic Process     

Tzu‐Yi Pai  Terng‐Jou Wan  Yung‐Pin Tsai  Chwen‐Jeng Tzeng  Hsiao‐Hsing Chu  Yao‐Sheng Tsai  Ching‐Yuan Lin 《洁净——土壤、空气、水》2010,38(2):167-172

In this study, the effect of sludge retention time on ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in an anaerobic/oxic (AO) process, was explored. The results indicated that the growth rate constants of AOB were 0.97, 0.88, and 0.79 d^–1, respectively, meanwhile, those of NOB were 1.22, 1.03, and 0.93 d^–1, respectively, when the sludge retention time (SRT) was 15 days, 10 days and 5 days. The relation between the growth rate constant and the SRT could be best described using a simple exponential curve and a second type hyperbolic curve. The lysis rate constants for AOB and NOB were 0.13 and 0.18 d^–1, respectively. The yield coefficients values of AOB and NOB were 0.22 and 0.21, respectively. The percentage of AOB to mixed liquid suspended solids (MLSS) was 0.64%, 0.53%, and 0.35%, respectively. Meanwhile, the percentage of NOB was 2.24%, 1.87%, and 1.11%, respectively, at SRT values of 15 days, 10 days and 5 days. When the SRT value decreased, the AOB and NOB biomass levels decreased by 12.75 and 47.01 mg L^–1, respectively. Meanwhile the removal efficiency of NH₄⁺‐N decreased from 90 to 26%, while the removal efficiency of total nitrogen (TN) decreased from 14 to 8%.  相似文献   

Bacterial wax esters in recent fluvial sediments     

《Organic Geochemistry》2015

We investigated the molecular inventory of River Danube sediments and identified wax esters with 28–36 carbons, with C₃₀, C₃₁ and C₃₂ homologs the most abundant. They consist of various combinations of n-, iso- and anteiso-aliphatic acid and alcohol moieties, with different isomer distributions for the esters with odd and even carbon numbers. The short chain length (C₂₈–C₃₆), high proportion of methyl moieties and presence of monounsaturated esters together suggest a bacterial origin for the wax esters. The concentration in surface sediments varied from 0 to 741 μg/kg, being significantly enriched at locations with high nutrient concentration and high primary productivity. Cluster analysis of denaturing gradient gel electrophoresis (DGGE) band patterns revealed different bacterial communities in surface sediments from the stream and surface sediments from the reservoir. The concentration in a 70 cm core of rapidly deposited sediments decreased significantly with depth, following first order kinetics, suggesting a loss of the esters within ca. 3 years following burial and hence a low probability for preservation in the geological record. Wax esters in rivers have rarely been investigated; our results suggest that they represent a bacterial response to enhanced primary production, triggered by higher nutrient supply.  相似文献   

Benthic foraminifera from the deep-water Niger delta (Gulf of Guinea): Assessing present-day and past activity of hydrate pockmarks     

《Deep Sea Research Part I: Oceanographic Research Papers》2014

We present ecological and isotopic (δ¹⁸O and δ¹³C) data on benthic foraminifera sampled from 4 deep-sea stations in a pockmark field from the deep-water Niger delta (Gulf of Guinea, Equatorial Atlantic Ocean). In addition, a series of sedimentological and (bio)geochemical data are shown to back up foraminiferal observations. All stations are located within 1.2 km of each other, so prevailing oceanographic conditions can be assumed to be similar at each site. Two of the sites (GMMC-01 and GMMC-02) are located in a pockmark (named “pockmark A”) where current methane seepages were recorded by ROV observations. A third station (GMMC-03) is located in the topographic depression interpreted as a collapsed pockmark (named “pockmark B”). The fourth site (GMMC-04) is a reference station, without evidence of past or present seepages. Our observations show that degraded organic matter with low bio-availability is present at all stations with a preferential burial of organic compounds in topographic depressions (GMMC-03 station). Authigenic aragonite is abundant in surface sediments at stations GMMC-01 and -02. Its precipitation is likely related to high rates of methane oxidation during past seep events in episodically active pockmark A. In contrast, the absence of anaerobic methanotrophic Archaea (ANME) during the sampling period (November 2011) suggests that only moderate sulphide and methane oxidation take place close to the sediment–water interface. Compared to the reference site GMMC-04, living foraminifera at the collapsed and episodically active pockmarks show minor changes in terms of diversity, standing stocks and faunal composition. However, the δ¹³C signal of living and dead (but well-preserved) foraminiferal species (Ceratobulimina contraria, Melonis barleeanus, Uvigerina peregrina) is depleted in the episodically active pockmark A compared to the other stations. Overgrowth of authigenic carbonate on altered foraminifera generates an important shift to lower δ¹³C values. Dead faunas carry a complex time-averaged message, integrating taphonomic gains and losses related to the temporal variability of gas emission. They reveal major faunal differences that may be useful to detect gas hydrate seepages in different pockmark stages.  相似文献