The methods of DAPI staining epifluorescence microscopy and T-RFLP analysis were used to analyze the microbial abundance and diversity in surface seawater sampled from 12 stations inside and outside of the Jiaozhou Ba...The methods of DAPI staining epifluorescence microscopy and T-RFLP analysis were used to analyze the microbial abundance and diversity in surface seawater sampled from 12 stations inside and outside of the Jiaozhou Bay during a survey on 12 and 13 September 2004. The abundance of total microbes is in the range of 10^6～ 10^7 cells/cm^3, similar to those of most semi-enclosed bays in the temperate areas in the world. The highest microbial densities occur in the northeastern part of the Jiaozhou Bay, around the mouths of Loushan and Licun Rivers and the Hongdao aquacultural farming areas, suggesting that the degree and characteristics of pollutions, along with geographical and hydrological effects, may be important determinants affecting the abundance and distribution of bacteria in the Jiaozhou Bay. Bacterial communities inside and outside of the Jiaozhou Bay can be grouped into three classes based on T-RFLP patterns and cluster analyses. Stations at the water channel of the bay mouth and outside, such as D1, D3, D5, D6 and D7, are grouped together to stand for the outside bacterial community interacting with the environment outside of the Jiaozhou Bay. Stations of the innermost side of the Jiaozhou Bay, such as A3, A5, B2 and Y1, are grouped together to stand for the residential bacteria community. Stations C1, C3 and CA are grouped together and may stand for the transitional bacterial assemblage between the residential community and the outside community. However, there is no such a defined relationship for the case of cyanobacterial diversity, indicating the fact that cyanobacteria are more flexible and adaptable to all kinds of conditions.展开更多
The cyanobacteria and physico chemical environments of six tropical fresh water lakes of Udaipur, India were investigated. These lakes receive varying nutrient inputs from different sources. Altogether 51 species of ...The cyanobacteria and physico chemical environments of six tropical fresh water lakes of Udaipur, India were investigated. These lakes receive varying nutrient inputs from different sources. Altogether 51 species of cyanobacteria were recorded. Species composition varied between lakes and between seasons. Lake VI (Baghdara), which receives nutrients from natural sources only, differed considerably from the others in water chemistry and composition of dominant species. Lake II (Swaroop Sagar), eutrophied due to sewage inputs, was species poor. Non diazotrophs, represented by 27 species, dominated during summer. With few exceptions, N 2 fixing species, both heterocystous and unicellular diazotrophs (represented by 24 species), were dominant during winter. Microcystis aeruginosa, Phormidium sp. and Anabaena flos aque were the dominant taxa of lakes characterized by sewage eutrophication. The study shows that both species diversity and community composition were affected by water chemistry.展开更多
Cyanobacteria from habitats within Gujarat have been poorly studied with regard to their diversity. In the present investigation eight morphologically distinct cyanobacterial isolates were obtained and characterized f...Cyanobacteria from habitats within Gujarat have been poorly studied with regard to their diversity. In the present investigation eight morphologically distinct cyanobacterial isolates were obtained and characterized from the fresh water and marine habitats. Identification was performed based on morphological features and on 16S rDNA sequences analysis. A phylogenetic tree based on 16S rDNA sequence of cyanobacterial isolates was prepared. Phylogenetic analysis clustered the eight morphologically distinct isolates into two distinct groups thus highlighting the importance of both morphological and genetic methods in studying cyanobacterial diversity.展开更多
Nansi Lake is located on the east line of the South-to-North Water Diversion Project in China. A comprehensive study was carried out to investigate the spatial and temporal distribution of cyanobacteria in the lake fr...Nansi Lake is located on the east line of the South-to-North Water Diversion Project in China. A comprehensive study was carried out to investigate the spatial and temporal distribution of cyanobacteria in the lake from June 2008 to May 2011 based on monthly sample monitoring from five stations. The effect of environmental factors on cyanobacterial abundance was also evaluated. The eyanobaeterial community contained 15 genera and 23 species. The cyanobacterial abundance of each monitoring station ranged from 0 to 1.53x 107 cells/L with an average of 1.45~ 106 cells/L, which accounted for 11.66% of the total phytoplankton abundance. The dominant species of cyanobacteria were Pseudanabaena （32.94%） and Merismopedia （19.85%）, not the bloom-forming algae such as Microcystis and Anabaena. In addition, the cyanobacterial community structure and water quality variables changed substantially over the survey period. Redundancy analysis （RDA） suggested that temperature and phosphorus were important environmental factors that affected cyanobacteria. Temperature was the most important factor affecting cyanobacterial abundance. The effect of phosphorus on cyanobacterial abundance was more notable in warm periods than in periods with low temperature.展开更多
The present study was conducted to provide a detailed understanding of the variation in cyanobacterial communities of Dongping Lake, which is the final water volume adjusting and storing lake in the east route of the ...The present study was conducted to provide a detailed understanding of the variation in cyanobacterial communities of Dongping Lake, which is the final water volume adjusting and storing lake in the east route of the South-to-North Water Diversion Project in China. The spatial and temporal distribution of cyanobacteria was assessed from May 2010 to October 2012 based on monthly samples collected from three stations. Over the 30-month survey, 15 genera and 25 species of cyanobacteria were identified, with cyanobacterial abundance at each monitoring station ranging from undetected to 3.04×10^7 cells/L, average of 4.27×10^6 cells/L. The dominant cyanobacterial species were Pseudanabaena limnetica and Aphanizomenon issatschenkoi and not the usual bloom-forming genera such as Microcystis and Anabaena. Cyanobacterial community structure and water quality variables exhibited substantial changes over the period of survey. Redundancy analysis, Pearson correlations, and regression analysis were applied to analyze the relationships among the variables. The results suggested that temperature and chemical oxygen demand were key drivers of the cyanobacterial community composition in Dongping Lake. In addition, the concentration of inorganic nitrogen in the lake had a profound effect on the cyanobacterial abundance as a non-limiting factor in warm periods.展开更多
基金financially supported by the Pilot Projects of Knowledge Innovation Project,Chinese Academy of Sciences under contract Nos KZCX3-SW-214,KZCX3-SW-223 and KZCX3-SW-233the National Natural Science Foundation of China under contract Nos 40476058 and 40576069.
文摘The methods of DAPI staining epifluorescence microscopy and T-RFLP analysis were used to analyze the microbial abundance and diversity in surface seawater sampled from 12 stations inside and outside of the Jiaozhou Bay during a survey on 12 and 13 September 2004. The abundance of total microbes is in the range of 10^6～ 10^7 cells/cm^3, similar to those of most semi-enclosed bays in the temperate areas in the world. The highest microbial densities occur in the northeastern part of the Jiaozhou Bay, around the mouths of Loushan and Licun Rivers and the Hongdao aquacultural farming areas, suggesting that the degree and characteristics of pollutions, along with geographical and hydrological effects, may be important determinants affecting the abundance and distribution of bacteria in the Jiaozhou Bay. Bacterial communities inside and outside of the Jiaozhou Bay can be grouped into three classes based on T-RFLP patterns and cluster analyses. Stations at the water channel of the bay mouth and outside, such as D1, D3, D5, D6 and D7, are grouped together to stand for the outside bacterial community interacting with the environment outside of the Jiaozhou Bay. Stations of the innermost side of the Jiaozhou Bay, such as A3, A5, B2 and Y1, are grouped together to stand for the residential bacteria community. Stations C1, C3 and CA are grouped together and may stand for the transitional bacterial assemblage between the residential community and the outside community. However, there is no such a defined relationship for the case of cyanobacterial diversity, indicating the fact that cyanobacteria are more flexible and adaptable to all kinds of conditions.
文摘The cyanobacteria and physico chemical environments of six tropical fresh water lakes of Udaipur, India were investigated. These lakes receive varying nutrient inputs from different sources. Altogether 51 species of cyanobacteria were recorded. Species composition varied between lakes and between seasons. Lake VI (Baghdara), which receives nutrients from natural sources only, differed considerably from the others in water chemistry and composition of dominant species. Lake II (Swaroop Sagar), eutrophied due to sewage inputs, was species poor. Non diazotrophs, represented by 27 species, dominated during summer. With few exceptions, N 2 fixing species, both heterocystous and unicellular diazotrophs (represented by 24 species), were dominant during winter. Microcystis aeruginosa, Phormidium sp. and Anabaena flos aque were the dominant taxa of lakes characterized by sewage eutrophication. The study shows that both species diversity and community composition were affected by water chemistry.
文摘Cyanobacteria from habitats within Gujarat have been poorly studied with regard to their diversity. In the present investigation eight morphologically distinct cyanobacterial isolates were obtained and characterized from the fresh water and marine habitats. Identification was performed based on morphological features and on 16S rDNA sequences analysis. A phylogenetic tree based on 16S rDNA sequence of cyanobacterial isolates was prepared. Phylogenetic analysis clustered the eight morphologically distinct isolates into two distinct groups thus highlighting the importance of both morphological and genetic methods in studying cyanobacterial diversity.
基金supported by the International Cooperation research of Shandong Province (No. 2008GJHZ20601)the International Science and Technology Cooperation Program of China (No. 2010DFA91150)the Policy and Technology Research Center of South-to-North Diversion Project Office,State Council (No. 20080521)
文摘Nansi Lake is located on the east line of the South-to-North Water Diversion Project in China. A comprehensive study was carried out to investigate the spatial and temporal distribution of cyanobacteria in the lake from June 2008 to May 2011 based on monthly sample monitoring from five stations. The effect of environmental factors on cyanobacterial abundance was also evaluated. The eyanobaeterial community contained 15 genera and 23 species. The cyanobacterial abundance of each monitoring station ranged from 0 to 1.53x 107 cells/L with an average of 1.45~ 106 cells/L, which accounted for 11.66% of the total phytoplankton abundance. The dominant species of cyanobacteria were Pseudanabaena （32.94%） and Merismopedia （19.85%）, not the bloom-forming algae such as Microcystis and Anabaena. In addition, the cyanobacterial community structure and water quality variables changed substantially over the survey period. Redundancy analysis （RDA） suggested that temperature and phosphorus were important environmental factors that affected cyanobacteria. Temperature was the most important factor affecting cyanobacterial abundance. The effect of phosphorus on cyanobacterial abundance was more notable in warm periods than in periods with low temperature.
基金supported by the International Science and Technology Cooperation Program of China (No. 2010DFA91150)the International Cooperation Research of Shandong Province (No. 2011176)+1 种基金the Science and Technology Development Project of Shandong Province (No. 2012GHZ30020)the Policy and Technology Research Center of South-to-North Diversion Project Ofce, State Council
文摘The present study was conducted to provide a detailed understanding of the variation in cyanobacterial communities of Dongping Lake, which is the final water volume adjusting and storing lake in the east route of the South-to-North Water Diversion Project in China. The spatial and temporal distribution of cyanobacteria was assessed from May 2010 to October 2012 based on monthly samples collected from three stations. Over the 30-month survey, 15 genera and 25 species of cyanobacteria were identified, with cyanobacterial abundance at each monitoring station ranging from undetected to 3.04×10^7 cells/L, average of 4.27×10^6 cells/L. The dominant cyanobacterial species were Pseudanabaena limnetica and Aphanizomenon issatschenkoi and not the usual bloom-forming genera such as Microcystis and Anabaena. Cyanobacterial community structure and water quality variables exhibited substantial changes over the period of survey. Redundancy analysis, Pearson correlations, and regression analysis were applied to analyze the relationships among the variables. The results suggested that temperature and chemical oxygen demand were key drivers of the cyanobacterial community composition in Dongping Lake. In addition, the concentration of inorganic nitrogen in the lake had a profound effect on the cyanobacterial abundance as a non-limiting factor in warm periods.
