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湖泊沉积物中微量金属二次迁移过程中微生物作用的实验研究 总被引：12，自引：1，他引：12
蓄积在湖泊沉积物中污染物质某些情况下可以成为威胁上覆水体水质安全的二次污染源．根据贵州省阿哈湖季节性缺氧的特性,通过控制氧化还原状况,设计了对该湖沉积物-水柱的原样／抑菌条件的培养实验．实验发现,微生物活动对界面附近氧化还原反应具有控制作用;改变水体的含氧状况可以显著影响上覆水体水质,包括表观性状和水体中污染物含量．聚类分析结果表明,早期成岩过程中Mn,Ga,SO4 2-,Cu,Cr,Pb和Co,Ni,Fe,Sc,V,Rb两大类分别具有相似的地球化学行为．根据实验结果,计算了厌氧培养过程中,微量元素的最大释放量,发现铁、锰在厌氧过程中可以大量向水体释放． 相似文献
2.
M. Bouvy R. Arfi C. Bernard C. Carré P. Got M. Pagano M. Troussellier 《Estuarine, Coastal and Shelf Science》2010
Understanding how human-induced management interacts with and affects the structure and functioning of large estuarine ecosystems is a major research challenge. In West Africa, human intervention on the Senegal River Estuary was intended to reduce the impact of major flooding by opening a new mouth in October 2003, 25 km to the north of the existing mouth. This study describes the effects of the new environmental conditions on the physical and biochemical characteristics of the water column and on microbial communities (bacteria, phytoplankton by size class and heterotrophic nanoflagellates (HNF)) in comparison with the situation in 2002. In 2006, seventeen stations were sampled, during both neap and spring tides, at a depth of 0.5 m along a salinity gradient from freshwater to marine conditions. Inorganic nutrient levels were often low but there were high levels of chlorophyll a in the estuarine area (mean of 13.7–20.7 μg L−1 in spring and neap tide conditions, respectively) producing a eutrophic status in this estuary. Average HNF abundances were lower (mean of 108 and 174 cells l−1 during neap and spring tides, respectively) compared to the situation in 2002 (mean between 2.5 and 6.7 × 104 cells l−1). Three biological indicators for assessing environmental changes are discussed: ratio of bacteria to heterotrophic flagellate abundances, ratio of picophytoplankton to nanophytoplankton, and the density of thermo-tolerant coliforms (TTC) and faecal streptococci. It is demonstrated that man-made alteration of the hydrologic regime can modify the microbial community structure and cause the health status of the estuary to deteriorate. 相似文献
3.
北极地区深海微生物研究进展及对策 总被引：2，自引：2，他引：0
对北极地区深海微生物研究进展进行了综述和展望分析,并提出强化我国北极深海微生物研究的对策,以期为相关研究和决策提供参考。综述表明北极深海微生物具有丰富的多样性,是数量巨大的遗传基因资源承载者,群落结构表现出显著的空间分布差异,在北极深海食物链中可能发挥着基础性作用。展望分析提出聚焦北极深海这一特殊的极端环境,开展微生物多样性和地理分布特征研究、新颖遗传生化功能挖掘以及多尺度生态系统下微生物与环境变化的研究具有重要意义和价值。建议我国顶层布局、构建北极深海微生物协同研究体系,提升专用配套仪器装备保障能力,全面推进相关研究工作。 相似文献
4.
地壳深部的微生物及其对流体成分和性质的影响研究综述 总被引：1，自引：0，他引：1
概述了地壳深部微生物区系的一些特征，它们的活动对流体成分和性质的影响，并对微生物生命的温度上限、下渗深度等问题进行了探讨。 相似文献
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Irina Shtangeeva Antti Vuorinen Bernd Rietz Liisa Carlson 《Geostandards and Geoanalytical Research》2001,25(2-3):299-306
A detailed characterisation was carried out for soil sampled from sites with different levels of contamination before and after the cultivation of oats and barley. Mineralogical composition, concentration of exchangeable cations, dynamics of soil pH and acid neutralisation buffer capacity of the soil were studied. A total of 21 elements in the soil and 28 elements in the plants were determined by instrumental neutron activation analysis. Distribution of Al, Cr, Mn, Fe, Co, Ni, Cu, Zn and Pb in soil leachates was studied by sequential leaching procedure and ICP-AES. It was found that plants significantly affect most of the soil characteristics including the leaching of heavy metals. 相似文献
6.
为了提高低温废水处理效果，筛选：和鉴定具有显著低温生活污水降解作用的南极微生物，并对其低温生活污水的处理效果进行了初步研究。实验结果表明，在0～5℃时。南极低温酋群对有机物的降解率显著高于中温菌的去除率，南极耐冷菌对NH3-N及TP均有一定的去除率。从南极低温茼群中筛选到5株蛋白质降解功能菌，4株脂肪降解功能菌，1株淀粉降解功能菌，2株烷烃降解功能菌和1株芳香烃降解菌，并通过16SrDNA序列对它们进行了鉴定，明确其菌属。这为寻求解决低温环境中废水处理的有效方法奠定了基础。 相似文献
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Parke A. Rublee Susan M. Merkel Maria A. Faust 《Estuarine, Coastal and Shelf Science》1983,16(5):501-509
The number of bacteria in sediments, interstitial water and overlying tidal water of an oligohaline marsh system are about 109, 106 and 106 cells cm?3, respectively. Average cell size in the overlying water (about 0·06 μm3), is much smaller than that in sediments and interstitial water (about 0·18 μm3). Most bacterial cells in sediments are bound to sediment particles and less than 1% of the cells were displaced by percolating water through sediment columns. Concentration of bacteria in flooding tidal waters is generally higher than that in ebbing waters. Movement of bacterial biomass does not appear to be a significant mechanism of particulate organic transport in marsh sediments and marsh sediments do not appear to be a source of suspended bacteria for estuaries. 相似文献
8.
S.A. Visser 《Organic Geochemistry》1985,8(1):81-85
The incorporation of humic acid fractions in media designed for the enumeration of soil micro-organisms belonging to specific physiological groups was found to result for some groups in appreciably higher counts. It is suggested that by influencing the enzyme systems of certain micro-organisms, humic compounds may affect the range of substrates which they can utilize. The effect could have implications on the activity of organisms in environments in which humic substances are normally present, such as soils and natural waters. 相似文献
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Loreta Fernandes Fraddry D’Souza S. G. P. Matondkar Narayan B. Bhosle 《Journal of Earth System Science》2006,115(3):363-370
Amino sugars (AS) are important constituents of organic matter. However, very little is known about their cycling in marine
waters. In this research, we assessed the distribution and cycling of these compounds in waters of the Bay of Bengal. For
this purpose, samples of suspended particu late matter (SPM) were collected from 8 depths (surface to 1000 m) at 6 locations
during the 166th cruise of the ORV Sagar Kanya in the Bay of Bengal in July/August 2001. The SPM samples were analysed for
particulate organic carbon (POC), particulate nitrogen (PN) and AS concentrations and composition. The AS varied between 0.4
and 17.5 nmol/l. Concentrations were high in the surface waters and generally decreased with increasing depth. AS concentration
decreased from the south to north. AS accounted for 0.01 to 0.71% and 0.05 to 2.37% of POC and PN, respectively. Rapid decrease
in AS-C% and AS-N% with depth indicates that these compounds were preferentially degraded relative to bulk POC and PN. The
composition of AS suggests that glucosamine (GLU-N) and galactosamine (GAL-N) were present in the surface SPM samples, and
their abundance decreased from surface downwards. Relatively, low values of GLU-N/GAL-N ratio indicate that the organic matter
was mostly derived from the detritus of micro-organisms. Our data suggest that chitin, a polymer of the glucosamine produced
by many marine organisms was not the major source of AS in the Bay. Rapid cycling of these compounds indicates their importance
in the cycling of nitrogen in marine waters 相似文献
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