含氯消毒剂用于细菌性虾病防治的药理     

王勇强 《中国海洋大学学报(自然科学版)》1992,(4)

探讨次氯酸钙和二氯异氰尿酸钠两种代表性含氯消毒药物,为含氯消毒剂应用于细菌性虾病的防治提供理论依据。实验表明:有效氯在海水中的丧失随温度上升、pH值下降而加速。常见对虾病原菌对有效氯非常敏感,有机物增加、pH值上升使杀菌率下降。两种药物对实验中国对虾的48h半致死浓度为2.74～2.88mg/L有效氯。长期施以高于安全浓度的药物对实验虾之存活率、增长率等指标无不良影响,施药组发病率远远低于对照组。  相似文献   

海带对褐藻酸降解菌的抗性与其SOD活性的相关性     

刘成圣  杨震  唐学玺 《海洋科学》2002,26(2):1-2

运用生物化学的方法测试了2个品系的海带对褐藻酸降解菌抗性的差异性，并对其SOD活性的高低进行了研究。结果表明，海带荣成1号（简称NO.1）对褐藻酸降解菌的抗性远远高于海带901（简称901）；海带荣成1号细胞内超氧化物歧化酶（SOD）的活性明显高于海带901，二者显著正相关。说明海带SOD活性的高低与其对褐藻酸降解菌的抗性大小有一定的相关性。  相似文献   

解磷菌分离及其对内蒙古布龙图低品位磷矿利用研究   总被引：1，自引：0，他引：1  

田晓娟  杜德平  王艳  吴永慧  彭立娥 《地球学报》2007,28(4):377-381

从内蒙古布龙图磷矿区表层土壤中取样,分离得到了几个解磷菌株,测定了每个菌株的解磷能力.分离的芽孢杆菌(Bacillus sp.)A20、AC2013和AC2015,对Ca3(PO4)2和磷矿石粉中磷的分解率为21%～25%,它们对磷的分解具有协同效应.用A20和AC2013的菌液制成的生物复合磷肥施于马铃薯,增产23.08%,微生物法将成为利用北方低品位磷矿的有效途径之一.  相似文献   

Effects of solar radiation on the fate of dissolved DMSP and conversion to DMS in seawater     

Doris Slezak  Ronald P. Kiene  Dierdre A. Toole  Rafel Simó  David J. Kieber 《Aquatic Sciences - Research Across Boundaries》2007,69(3):377-393

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Aerosol bacteria over the Southern Ocean during ACE-1     

Mihly Psfai  Jia Li  James R. Anderson  Peter R. Buseck 《Atmospheric Research》2003,66(4):231

Individual bacterial cells occur in many samples that were collected at Cape Grim, Tasmania and during the Lagrangian “B” experiment of the Aerosol Characterization Experiment 1 (ACE-1) campaign that was conducted above the Southern Ocean. They are present in samples from altitudes as high as 5.4 km. Morphologically, almost all bacteria are rod-shaped, about 1 μm long or smaller, have one polar flagellum, and contain inclusions that are rich in P and K. Their morphological features suggest that these bacteria are motile, marine species. It seems likely that the cells became airborne by the same bubble-bursting mechanism that ejects sea-salt aerosol particles into the atmosphere; however, the bacteria and sea-salt particles are typically not aggregated with one another. The estimated number ratio of bacteria and the dominant aerosol species, sea salt, varies in the samples and averages about 1%. The aerosol bacteria seem to represent an important atmospheric reservoir of P and organic compounds; on the other hand, since they are externally mixed with sea salt, they are unlikely to be effective as cloud condensation nuclei.  相似文献   

Lipid biomarkers and carbon-isotopes of modern travertine deposits (Yellowstone National Park, USA): Implications for biogeochemical dynamics in hot-spring systems     

Chuanlun L. Zhang  Bruce W. Fouke  Aaron D. Peacock  Yongsong Huang 《Geochimica et cosmochimica acta》2004,68(15):3157-3169

Lipid biomarkers and ¹³C fractionation patterns were used to understand the dynamics of carbon cycling during microbial metabolisms in different environments of travertine precipitation (called facies) at Spring AT-1 on Angel Terrace in the Mammoth Hot Springs complex of Yellowstone National Park, USA. Microbial mats that encrust travertine deposits were collected for analyses of lipid biomarkers and carbon isotopes along the continuous drainage outflow system of Spring AT-1. The spring water exhibits a continuous temperature drop from 71°C in the vent at top to 24°C in the distal slope at bottom. Phospholipid fatty acids (PLFA) and glycolipid fatty acids (GLFA) exhibit distinctly different compositions in each of the facies, which are consistent with partitioning of the bacterial 16S rRNA gene sequences in the Spring AT-1 travertine facies (Fouke et al., 2003).The δ¹³C composition of total biomass within the microbial mats decreases from −16.1‰ in the vent to −23.5‰ in the distal slope. However, lower values occur in the pond (−26.0‰) and the proximal slope (−28.0‰) between the vent and the distal slope. Isotopic compositions of PLFA and GLFA have variations similar to those of total biomass. The average δ¹³C values of PLFA are −12.4 ± 5.2‰ (n = 10 individual fatty acids, same below) in the vent, −33.0 ± 3.1‰ (n = 11) in the pond, −33.7 ± 3.8‰ (n = 16) in the proximal slope, and −22.4 ± 3.4‰ (n = 10) in the distal slope; the average δ¹³C values of GLFA are −19.6 ± 3.0‰ (n = 3) in the vent, −30.4 ± 4.7‰ (n = 8) in the pond, −36.9 ± 2.8‰ (n = 12) in the proximal slope, and −27.9 ± 3.1‰ (n = 13) in the distal slope. In particular, fatty acids in the vent are enriched in ¹³C relative to the total biomass, which is consistent with the notion that the biosynthetic pathways of the extant microbial community in the vent may be dominated by Aquificales using the reversed tricarboxylic acid cycle. Fractionations between fatty acids and total biomass in the pond, the proximal slope and the distal slope suggest the involvement of other biosynthetic pathways for CO₂ fixation by extant microbial populations. The results indicate that lipid biomarkers provide valuable information on the changing diversity and activity of microbial communities in different depositional environments. Carbon-isotope fractionations, on the other hand, can provide insight into the operating biosynthetic pathways associated with different organisms in the changing environment. This integrated approach may serve as a powerful tool for identifying functional metabolism within a community and identify shifts in microbial community structure in modern hot-spring systems.  相似文献   

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