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1.
胶州湾异养细菌及大肠菌群的分布及对陆源污染的指示   总被引:3,自引:3,他引:0  
2002年2月—2004年11月对胶州湾异养细菌和大肠菌群进行长期调查发现,胶州湾异养细菌丰度在105—106cells/ml之间,其中河口区域和近岸区域数量较高,其它区域相对较低。从季节上来看,夏季、秋季细菌丰度较高(分别为7.4×105、7.2×105cells/ml),冬季和春季丰度较低(分别为4.1×105cells/ml、5.9×105cells/ml),且在一年内呈现出一定的规律性波动。从季节尺度上看异养细菌丰度与温度呈现很好的正相关性(R=0.54)。对大肠菌群的研究表明,河口区域的大肠菌群数量显著高于其它区域,并且河口区域大肠菌群常年处于严重超标状态(最高为1.1×106cells/L,超过国家前三类水质标准的100倍)。根据大肠菌群的数量状况可以将胶州湾分为三个区域,即严重污染区、中度污染区和轻度污染区。该区域划分与通过营养盐对胶州湾区域的划分(富营养区、中度营养区、贫营养区)结果一致。  相似文献   
2.
海洋浮游细菌在碳循环中的作用   总被引:2,自引:2,他引:0  
由于海洋浮游细菌(marine bacterioplankton)在全球碳循环中非常重要,浮游细菌的生物学和生态学研究成为当前生物海洋学最活跃的前沿领域之一。浮游细菌主要包括异养细菌(heterotrphic bacteria)和超微型光合原核生物(picoprokaryotes)蓝细菌(Synechococcus,聚球菌属,细胞粒径为0.5-1.5μm)  相似文献   
3.
秋季东、黄海异养细菌(Heterotrophic Bacteria)的分布特点   总被引:28,自引:1,他引:27  
2000年10-11月,乘"北斗号"考察船进行秋季"东、黄海生态系统动力学与生物资源可持续利用"大面调查,研究秋季东、黄海异养细菌的分布.结果表明,异养细菌在黄海和东海的丰度分别在(2.37-13.33)×108 cell/L和(3.05-13.62)×108 cell/L之间.细菌丰度最高值出现在长江口附近,且断面E和断面F各站位的细菌丰度明显高于其他断面.异养细菌丰度大小以长江口为中心向外海依次递减.东、黄海水体异养细菌生物量分别在244.45-1812.90mgC/m2和100.60-940.87mgC/m2之间.东、黄海异养细菌丰度无显著差异,但是东海海域水体异养细菌生物量高于黄海海域.异养细菌空间分布与浮游植物叶绿素在东海有一定的相关性,黄海异养细菌与硝酸盐浓度的相关性极显著.  相似文献   
4.
Flow cytometric determinations of the abundance distribution and community structure of picophytoplankton (i.e.,Prochlorococcus spp.,orange fluorescence Synechococcus spp.and picoeukaryotes) were used for samples taken from the Philippine Sea in the western tropical Pacific Ocean from September to October of 2004.A fluorescence probe was employed to detect Chlorophyll a (Chl a).Abundances of Prochlorococcus spp.,orange fluorescence Synechococcus spp.and picoeukaryotes ranged from 0.1 to 58×103 cells ml-1,0.38 to 17×102 cells ml-1 and 0.42 to 26×102 cells ml-1,respectively.Synechococcus spp.and picoeukaryotes co-occurred in relatively shallow water with the maximum abundance observed at 50 to 70 m depth,while Prochlorococcus spp.only occurred in the 70 to 200 m layer.Prochlorococcus spp.was the dominant picophytoplankton population in terms of abundance and biomass.The cell size and carbon biomass content were estimated for the three picophytoplankton groups.In addition,among the three groups of picophytoplankton,the relative contribution of red fluorescence to the total red fluorescence varied with depth.The fluorescence and light scatter properties of individual cells indicated that in the upper 100 m layer,picoeukaryotes were a major contributor to total red fluorescence,while at the depth below 100 m,Prochlorococcus spp.and Synechococcus spp.made an important contribution to the total red fluorescence.  相似文献   
5.
兼容VGI与众包的灾害信息管理系统研究   总被引:1,自引:0,他引:1  
针对地理信息采集VGI和众包传播模式在灾害救援中发挥的巨大作用,设计并实现了兼容VGI与众包的灾害信息管理系统VDMS,实例验证了该系统的有效性。结果表明:VDMS系统可以将VGI众包采集流程集成到灾害信息管理中,提高了灾害信息采集效率。设计了一种灾害信息管理系统VDMS,实现了灾害发生时海量数据的高效管理与有效利用。  相似文献   
6.
Magnetospirillum magneticum strain AMB-1 belongs to the family of magnetotactic bacteria. It possesses a magnetosome chain aligning, with the assistance of cytoskeleton filaments MamK, along the long axis of the spiral cells. Most fresh M. magneticum AMB-1 cells exhibit spiral morphology. In addition, other cell shapes such as curved and spherical were also observed in this organism. Interestingly, the spherical cell shape increased steadily with prolonged incubation time. As the actin-like cytoskeleton protein MreB is involved in maintenance of cell shapes in rod-shaped bacteria such as Escherichia coli and Bacillus subtilis, the correlation between MreB protein levels and cell shape was investigated in this study. Immunoblotting analysis showed that the quantity of MreB decreased when the cell shape changed along with incubation time. As an internal control, the quantity of MamA was not obviously changed under the same conditions. Cell shape directs cell-wall synthesis during growth and division. MreB is required for maintaining the cell shape. Thus, MreB might play an essential role in maintaining the spiral shape of M. magneticum AMB-1 cells.  相似文献   
7.
Flow cytometric determinations of the abundance distribution and community structure of picophytoplankton (i.e., Prochlorococcus spp., orange fluorescence Synechococcus spp. and picoeukaryotes) were used for samples taken from the Philippine Sea in the western tropical Pacific Ocean from September to October of 2004. A fluorescence probe was employed to detect Chlorophyll a (Chl a). Abundances of Prochlorococcus spp., orange fluorescence Synechococcus spp. and picoeukaryotes ranged from 0.1 to 58×103 cells ml?1, 0.38 to 17×102 cells ml?1 and 0.42 to 26×102 cells ml?1, respectively. Synechococcus spp. and picoeukaryotes co-occurred in relatively shallow water with the maximum abundance observed at 50 to 70 m depth, while Prochlorococcus spp. only occurred in the 70 to 200 m layer. Prochlorococcus spp. was the dominant picophytoplankton population in terms of abundance and biomass. The cell size and carbon biomass content were estimated for the three picophytoplankton groups. In addition, among the three groups of picophytoplankton, the relative contribution of red fluorescence to the total red fluorescence varied with depth. The fluorescence and light scatter properties of individual cells indicated that in the upper 100 m layer, picoeukaryotes were a major contributor to total red fluorescence, while at the depth below 100 m, Prochlorococcus spp. and Synechococcus spp. made an important contribution to the total red fluorescence.  相似文献   
8.
Magnetospirillum magneticum strain AMB-1 belongs to the family of magnetotactic bacteria. It possesses a magnetosome chain aligning, with the assistance of cytoskeleton filaments MamK, along the long axis of the spiral cells. Most fresh M. magneticum AMB-1 cells exhibit spiral morphology. In addition, other cell shapes such as curved and spherical were also observed in this organism. Interestingly, the spherical cell shape increased steadily with prolonged incubation time. As the actin-like cytoskeleton protein MreB is involved in maintenance of cell shapes in rod-shaped bacteria such as Escherichia coli and Bacillus subtilis, the correlation between MreB protein levels and cell shape was investigated in this study. Immunoblotting analysis showed that the quantity of MreB decreased when the cell shape changed along with incubation time. As an internal control, the quantity of MamA was not obviously changed under the same conditions. Cell shape directs cell-wall synthesis during growth and division. MreB is required for maintaining the cell shape. Thus, MreB might play an essential role in maintaining the spiral shape of M. magneticum AMB-1 cells.  相似文献   
9.
自2002—2004年应用表面荧光显微镜计数法对胶州湾聚球菌(Synechococcusspp.)蓝细菌的季节变化、月变化及其对浮游植物总初级生产力的贡献进行调查研究。结果显示,胶州湾Synechococcusspp.丰度处于0.16×104—21×104cells/ml之间,最大与最小值之间相差约两个数量级,其中夏天Synechococcusspp.丰度最高,春、秋季相当,冬季最低。夏季Synechococcusspp.丰度平均值约是冬季的3—4倍。Synechococcusspp.的季节变化呈现一定周期性。Synechococcusspp.月最高值(21×104cells/ml)出现在8月的B2站表层,最低值(0.15×104cells/ml)出现在12月A1站表层。对18个月的胶州湾Synechococcusspp.水平分布进行分析,结果显示,河口和近岸区域Synechococcusspp.丰度相对较高。以D8站为典型站位对Synechococcusspp.垂直分布进行的分析发现,不同季节Synechococcusspp.最大值出现的水深不同。胶州湾Synechococcusspp.在总浮游植物生物量中所占的比例在0.2%—77%之间,平均为4.7%。此外,对2003—2004年温度与Syne-chococcusspp.丰度的相关性分析中发现,两者呈正线性相关(相关系数达0.6)。  相似文献   
10.
海洋异养细菌生物量与生产力的研究方法   总被引:4,自引:2,他引:2  
随着人类对海洋生态系统的不断研究和探索,海洋异养细菌在海洋生态系统物质循环、能量流动及维持海洋生态系统多样性与稳定性方面的重要性被人们广泛认可并展开深入研究。国际领域的一些有关海洋与全球变化的重大研究项目如:全球海洋生态系统动力学研究、全球海洋通量联合研究及  相似文献   
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