长春市"2000-04-07"远源沙尘湿沉降携带细菌研究   总被引：3，自引：1，他引：3  

吴东辉  胡克  王云  杨德明 《中国沙漠》2003,23(6):652-655

2000年4月5日～7日袭击我国西北地区北部、华北、东北南部、黄淮地区的扬沙或沙尘暴波及到长春市，带来了大量降尘的同时，还有大量细菌侵入。据长春市中西部解放立交桥和南湖公园取样测定，4月7日市区“泥雪”湿沉降，经实验室48h细菌培养，需氧细菌含量解放立交桥每毫升样品8．9万个、南湖公园10．5万个，市区每平方米“泥雪”携带细菌量平均达6．4亿个左右；细菌生化反应鉴定，未发现致病菌存在，杂菌数量及种类很多，解放立交桥与南湖公园样品细菌种属组成有一定差异。  相似文献   

Artemia parthenogenetica in Lake Hayward, Western Australia. II. Feeding biology in a shallow, seasonally stratified, hypersaline lake     

Alan Savage  Brenton Knott 《International Journal of Salt Lake Research》1998,7(1):13-24

Primary production in Lake Hayward, Western Australia, is dominated by benthic microbial communities, with limited planktonic primary production. This study investigated the question of howArtemia, commonly regarded as simple, obligate, non-selective filter feeders, were able to survive in this system. Bacteria (heterotrophic and autotrophic, filamentous and unicellular) were the major components in the diet of theArtemia in Lake Hayward. These bacteria were derived from bacterial aggregates in the water column and also from benthic mat material (both still attached to the substrate and from pieces floating in the water column). Benthic diatoms were a substantial dietary component of animals living in the unstratified shallow regions. Photosynthetic eukaryotic nanoplankton comprised a minor component of the diet of thisArtemia population. Gut contents of a large number of animals and the results of a simple laboratory test indicated that these animals utilise substrate-bound food resources. The results of the present study raises the question of the ecological significance of surface grazing by brine shrimps in other shallow, benthos dominated saline systems.  相似文献   

光合细菌在马氏珠母贝育苗中的应用     

刘志刚  吴勇胜 《广东海洋大学学报》1998,(1)

研究了光合细菌（下简称PSB）作为饵料添加剂在马氏珠母贝育苗中的饵料效果。结果表明：（1）单独投喂PSB,幼虫能生长发育并附着变态形成稚贝,但其长速、稚贝总育成率均低于单独投喂单胞藻的对照组;（2）用PSB与单胞藻混合投喂,幼虫的长速、稚贝总育成率均高于对照组;（3）添加PSB后,在眼点幼虫附着前不换水,幼虫的长速和眼点形成率均高于换水;但在眼点幼虫进入附着期仍不换水,则稚贝生长速度,总育成率均低于换水;（4）当PSB菌液密度为10×10-6个／cm3时,PSB投喂量以每天25×10-6为最佳,稚贝总育成率达到26．6％,而对照组仅为4．6％。  相似文献   

热泉热液金矿化中嗜热微生物——有机质的地球化学作用   总被引：3，自引：0，他引：3  

潘海祥  陆元法 《矿物岩石》1998,18(3):45-50

本文主要通过对热泉热液金成矿过程中的热泉水化学成分和组分的分析,得出泉水中金与氮磷硫、氟硅碳两组组分有很好的相关性。嗜热硫酸盐还原菌能使［Ａｕ（ＨＳ）２］－和［Ａｕ（Ｓ２Ｏ３）２］３－都氧化还原成硫化物,从而使金由热水溶液中沉淀。热泉沉积软泥的有机质中的含硫氨基酸、含硫芳烃也起到了一定的聚金作用。  相似文献   

Fossil bacteria in Xuanlong iron ore deposits of Hebei Province     

DAI Yongding  SONG Haiming & SHEN Jiying Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing  China 《中国科学D辑(英文版)》2004,47(4)

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Microbial lipids from a nearshore sediment from Bowling Green Bay,North Queensland: The fatty acid composition of intact lipid fractions     

Frank T. Gillan  Mark W. Sandstrom 《Organic Geochemistry》1985,8(5):321-328

Samples from a sediment core collected in Bowling Green Bay, North Queensland have been analysed for hexane/isopropanol extractable lipids and fatty acids. These data revealed a subsurface lipid abundance maximum at 3–4 cm depth and consistent low total fatty acid abundances (ca 2 μg/g) in the deeper samples ( > 10 cm depth). Lipid phosphate was below the level of detection in all the samples. Bacterial community structure was found to vary markedly in the upper 10 cm of the core, with the 18:1Δ11 bacterial chemotype predominant in the surface sediment and trans-acid chemotypes dominating in the 3–4 cm depth sediment. Based on the fatty acid composition, the bacterial biomass was estimated to vary from 199 μg/g at 3–4 cm depth toca 8 μg/g at 11–13 cm depth, although the fatty acid distributions indicated possible interference from protozoan detritus. In order to test this possibility, a surface sediment sample from a nearby site was extracted and analysed for fatty acids in lipid fractions separated by silica column chromatography. The fatty acid distributions in lipid fractions containing wax/steryl esters, triacylglycerols, glycolipids and phospholipids were markedly different. These analyses were interpreted in terms of fatty acid contributions to the extractable lipids from bacteria, cyanobacteria, protozoan detritus and highly degraded organic matter.  相似文献   

四川松潘东北寨金矿预富集过程中的菌藻成矿作用   总被引：10，自引：2，他引：10  

殷鸿福  谢树成 《地球科学》1992,17(3):241-249

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Seasonal changes of microbial populations in the sediments of the basins of Lugano and Agno     

Raffaele Peduzzi  Antonella Demarta  Mauro Tonolla 《Aquatic Sciences - Research Across Boundaries》1992,54(3-4):331-337

This research was carried out with the aim to explore the heterotrophic microbial population of two sediments in different oxic conditions of the Lake of Lugano (Lago di Lugano). The values of the viable bacterial counts found in our sediment samples were typical for an eutrophic lake.The increase in the proportion of anaerobic to aerobic bacteria at 30 °C observed in the sediment samples of Agno may reflect the depletion of oxygen concentrations in the water column.The generaAeromonas, Pseudomonas, Bacillus andClostridium, as well as strains belonging to the Coryneform-group, represented the major taxonomic groups of heterotrophic bacterial communities in the water-sediment interface.  相似文献   

海洋古细菌分子化石   总被引：2，自引：0，他引：2  

张水昌  卢松年 《地球科学》1993,18(4):391-392

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Hydroxy acids in Antarctic lake sediments and their geochemical significance     

Genki I. Matsumoto  Kunihiko Watanuki  Tetsuya Torii 《Organic Geochemistry》1988,13(4-6)

Hydroxy acids in sediments of Lakes Bonney, Fryxell, Joyce and Vanda, and unnamed ponds (B2, NF1, NF2 and L4) as well as in cyanobacterial mats from the McMurdo Sound region of southern Victoria Land in Antarctica have been studied to clarify their features and elucidate their source organisms. Normal and branched (iso and anteiso) 2-hydroxy acids were found in all the samples studied with the predominance of even- and odd-carbon numbers, respectively. The most dominant 2-hydroxy acids in the sediments were mainly short-chain components (<C₂₀). Normal and branched 3-hydroxy acids were detectewith the predominance of even- and odd-carbon numbers, respectively, in total concentrations between 0.48 and 53 μg/g of dry sediment. (ω-1)-Hydroxy acids were all long-chains (C₂₂, C₂₄, C₂₆, C₂₈ and C₃₀). 9,10-Dihydroxyhexadecanoic and/or 9,10-dihydroxyoctadecanoic acids were identified in all the sediments and a cyanobacterial mat. The composition of hydroxy acids differ considerably among the lakes and ponds, suggesting the difference of source organisms. These 2-, 3- and (ω-1)-hydroxy, and 9,10-dihydroxy acids may be derived from cyanobacteria and microalgae, in addition to non-photosynthetic microorganisms. Cyanobacteria and microalgae which are widely distributed in the world, may be important sources of hydroxy acids in the natural environments.  相似文献