The cell density, species composition and distribution of phytoplankton, and their relations to environmental factors in Prydz Bay and its adjacent sea area, Antarctica (69degrees-77degrees E, 62degrees-70degrees S) d...The cell density, species composition and distribution of phytoplankton, and their relations to environmental factors in Prydz Bay and its adjacent sea area, Antarctica (69degrees-77degrees E, 62degrees-70degrees S) during the austral summer of 1998/1999 were investigated. A total of 48 taxa belonging to 21 genera of phytoplankton in the sea area were identified. The average cell density of phytoplankton was 22.46 x 10(3) cells/dm(3), of which diatoms were predominant (84.51%). The highest cell density of phytoplankton occurred in Prydz Bay and the adjacent continental shelf where the average cell density was 46.03 x 10(3) cells/dm(3). The lowest cell density (3.34 x 10(3) cells/dm(3)) occurred in deep sea area. The dominant species of phytoplankton was Fragilariopsis curta. The vertical distribution of phytoplankton density was highest in the upper part of 0-50 in depth, lower in 100 in and lowest in 150 in. The species composition and cell density of phytoplankton were influenced by water circulation. The cell density was positively correlated with water temperature and salinity, and negatively correlated with the concentration of nutrients.展开更多
Microzoopiankton community composition in the north of South China Sea was investigated during autumn (between September and October), 2004. Dilution technique using chlorophyll a (Chl a) was employed to estimate ...Microzoopiankton community composition in the north of South China Sea was investigated during autumn (between September and October), 2004. Dilution technique using chlorophyll a (Chl a) was employed to estimate grazing rates and grazing pressure. The results showed that Polymenophorea Oligotrichida was the dominant group with 16 species, and there were 4 species in Oligotrichina and 11 species in Tintinnina. The ciliates abundance ranged from 9 to 102 ind/m^3, instantaneous growth rates of phytoplankton (k) varied from 0.03 / d to 2.13 / d. Grazing rates of microzooplankton(g) ranged between 0.01 / d and 1.06 / d. The grazing pressure on initial phytoplankton stock (Pi) and primary production (Pp) was 0.089 % - 65.23 % and 33.63 % - 86.04 %, respectively. The grazing of microzooplankton was mainly limited by ciliates abundance. Results of grazing pressure on primary production indicated that microzooplankton played an improtant role in transmitting primary production in the north of South China Sea.展开更多
This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of ...This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of phytoplankton growth and the different profiles of the change of its assemblage structure influenced by nutrient silicon and water temperature. Taking Jiaozhou Bay for example, this paper showed the process of both the variation of phytoplankton growth and the change of its assemblage structure, unveiled the mechanism of nutrient silicon and water temperature influencing the variation of phytoplankton growth and the change of its assemblage structure, and determined that nutrient silicon and water temperature were the motive power for the healthy running of the marine ecosystem.展开更多
Based on the samples collected from the Chukchi Sea during the FCNARE cruise from July to August in 1999 with the "Xuelong", the research vessel of SOA, China, the relationship between the distribution characterizat...Based on the samples collected from the Chukchi Sea during the FCNARE cruise from July to August in 1999 with the "Xuelong", the research vessel of SOA, China, the relationship between the distribution characterization of phytoplankton and environmental factors was analyzed with Primer 5.2 software. The result showed that the assemblages of phytoplankton in Chukchi Sea can be divided into three ecological groups: Arctic-boreal group, distributed mostly in northeastern ice-edge where the depth is more than 2 000 m and affected directly by Arctic Ocean; Boreal group, distributed in shelf-break ice in the center water where the depth is less 100 m; Eurythermal group, mainly distributed in the south which exchanged with North Pacific water through Bering Strait. The species diversity, cell density and distribution variability of phytoplankton among stations were great different. The range of phytoplankton density among stations was 1.6 × 10^3- 90 680.2 × 10^4 cells/m^3, and the ranges of diversity index and evenness index among stations were 0.07 - 0.87 and 0.33 - 3.82, respectively. Principal components analysis (PCA) showed that temperature and salinity had made important roles in the distribution of phytoplankton in the Chukchi Sea. Furthermore, the different influences of the variant water regimes, and the extremely dynamic physical nature of the drifting pack ice (e.g. packing, breaking up and melting ) introduce short-term variability into the water conditions that no doubt affect the phytoplankton distrubition.展开更多
[Objective] Surveys of phytoplankton were taken during the autumn of 2009 along Anhui-Jiangsu reaches of the Yangtze River to understand the species com- position and their spatial distributions. [Method] Phytoplankto...[Objective] Surveys of phytoplankton were taken during the autumn of 2009 along Anhui-Jiangsu reaches of the Yangtze River to understand the species com- position and their spatial distributions. [Method] Phytoplankton species, their quanti- ties, biomass and the Mcnaughton's dominance indices were all measured and their spatial distribution characteristics were determined using cluster analysis. [Result] There were 27 species, belonging to 5 phyla, namely Chlorophyta, Bacillariophyta, Cyanophyta, Euglenophyta and Cryptophyta, of phytoplankton collected and identified from the surveys. Results showed that Bacillariophyta was the predominant phyto- plankton with 16 species collected which accounted for 59.3% of the total species identified. The number of species collected belonging to Chlorophyta, Cyanophyta, Cryptophyta and Euglenophyta were 6, 2, 2, and 1, accounting for 22.2%, 7.4%, 7.4% and 3.7% of the total number identified, respectively. At the species level, the predominant species were Fragilaria crotonensis, Melosira italica, Navicula crypto- cephala, Cyclotella striata and Chroomonas acuta. Phytoplankton abundance was ranging from 5.68×10^4 to 7.08×10^4 cells/L with its average of 6.01×10^4 cells/L. Phyto- plankton biomass was ranging from 30.43 to 34.73 μg/L with its average of 32.46 μg/L. Compared with the previous reports, the number of phytoplankton species was decreased but its abundance and biomass was increased along the Jiangsu reach of the Yangtze River. However, Bacillariophyta species were still the predominant species and the phytoplankton community structure had not significantly changed from the previous studies. [Conclusion] These results might be explained as that the water quality in the Yangtze River was deteriorated but had not come to the worst. The results of similarity analysis gave two clusters of phytoplankton community as Nanjing, Wuhu and Jiangyin sampling sites were clustered into one group and Tongling and Anqing were clustered into another group.展开更多
Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosp...Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosphorus- (P), iron- (Fe), and cobalt- (Co) enriched incubations in the South China Sea in November 1997. Variations in abundance of the 4 groups of microorganism and cellular pigment content of the autotrophs during incubation were followed by flow-cytometric measurements for seven days. During the incubation, Syn and Euk showed a relatively higher demand on Fe and N, while Pro required higher levels of Co and P. The Fe was inadequate for all the organisms in the deep euphotic zone (75 m) of the study area. The experimental results also implied that biological interaction among the organisms played a role in the community structure shift during the incubation. It seemed that besides the effects of temperature, there are some other physical and chemical limitations as well as impacts from biological interactions on Pro distribution in coast waters.展开更多
Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS...Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS and DMSPp levels showed remarkable temporal and spatial variations. High values occurred in the coastal or shelf waters and low values in the offshore waters. The highest levels were observed in spring or summer and lowest in autumn. DMS or DMSPp distribution patterns were associated with water mass on a large geographical scale, while biological and chemical factors were more likely influential on smaller-scale variations. Diatoms could play an important role in total DMS or DMSPp abundance in coastal waters. Nitrate was found to have a two-phase relationship with DMSPp concentrations: positive when nitrate concentration was lower than 1 mumol/L, and negative when it was above. Anthropogenic factors such as sewage input and aquaculture also showed influences on DMS or DMSPp concentration.展开更多
[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,ph...[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.展开更多
A algal bloom process had been simulated via field mesocosm experiment, and the change of phytoplankton assemblage of different sizes in different growing phases had been studied. Nutrients addition could promote the ...A algal bloom process had been simulated via field mesocosm experiment, and the change of phytoplankton assemblage of different sizes in different growing phases had been studied. Nutrients addition could promote the growth of phytoplankton In the mesocosm of Prorocentrum donghaiense (M1) and the mesocosm of natural waters (M2), and the peaks of chlorophyll a were 112.79 mg/m and 235.60 mg/m, respectively. The restraining effect of nano-phytoplankton on pico-phytoplankton growth was stronger in M2 than in M1. When nutrients were abundant, the relative growth rate of diatom was higher than that of P. donghaiense, and they reached the peak quickly and then came to die out very fast. The decreasing of Si promoted diatom bloom to die out.展开更多
[Objective] This study aimed to investigate the dominant populations of late-summer phytoplankton and conduct comprehensive nutritional evaluation of water quality in Bailang Lake. [Method] A series of water quality s...[Objective] This study aimed to investigate the dominant populations of late-summer phytoplankton and conduct comprehensive nutritional evaluation of water quality in Bailang Lake. [Method] A series of water quality survey and phytoplankton sampling was conducted in Bailang Lake in September 2011, a total of four sam- pling points were set, to detect and analyze the total nitrogen, total phosphorus, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen and permanganate index in water samples and further conduct comprehensive nutritional evaluation of the water quality factors using comprehensive nutritional state index method. [Result] Water in Bailang Lake was neutral to slightly alkaline with pH of 8.57. The average water trans- parency was 0.4 m, with relatively high content of dissolved oxygen. The content of total nitrogen was relatively high of 3.043 mg/L averagely. Comprehensive nutritional evaluation showed that the water quality of Bailang Lake belonged to moderate eu- trophication. As can be seen from various comprehensive nutritional state indices TLI, the contribution of transparency, chlorophyll a and total nitrogen to the eutrophi- cation in Bailang Lake was the greatest, followed by the permanganate index and total phosphorus. Statistical analysis showed that the average weight-biomass of phy- toplankton in Bailang Lake was 6.442 mg/L, and the average was 146.46x104 individuals/ml. There were eight dominant species in Bailang Lake, including Scenedesmus, Tetraedron, Merismopedia sinica, Phormidium, Merismopedia, Tribonema, Chroomonas and Synedra. [Conclusion] This study provided data informa- tion for the environmental protection and fisheries production in Bailang Lake.展开更多
文摘The cell density, species composition and distribution of phytoplankton, and their relations to environmental factors in Prydz Bay and its adjacent sea area, Antarctica (69degrees-77degrees E, 62degrees-70degrees S) during the austral summer of 1998/1999 were investigated. A total of 48 taxa belonging to 21 genera of phytoplankton in the sea area were identified. The average cell density of phytoplankton was 22.46 x 10(3) cells/dm(3), of which diatoms were predominant (84.51%). The highest cell density of phytoplankton occurred in Prydz Bay and the adjacent continental shelf where the average cell density was 46.03 x 10(3) cells/dm(3). The lowest cell density (3.34 x 10(3) cells/dm(3)) occurred in deep sea area. The dominant species of phytoplankton was Fragilariopsis curta. The vertical distribution of phytoplankton density was highest in the upper part of 0-50 in depth, lower in 100 in and lowest in 150 in. The species composition and cell density of phytoplankton were influenced by water circulation. The cell density was positively correlated with water temperature and salinity, and negatively correlated with the concentration of nutrients.
文摘Microzoopiankton community composition in the north of South China Sea was investigated during autumn (between September and October), 2004. Dilution technique using chlorophyll a (Chl a) was employed to estimate grazing rates and grazing pressure. The results showed that Polymenophorea Oligotrichida was the dominant group with 16 species, and there were 4 species in Oligotrichina and 11 species in Tintinnina. The ciliates abundance ranged from 9 to 102 ind/m^3, instantaneous growth rates of phytoplankton (k) varied from 0.03 / d to 2.13 / d. Grazing rates of microzooplankton(g) ranged between 0.01 / d and 1.06 / d. The grazing pressure on initial phytoplankton stock (Pi) and primary production (Pp) was 0.089 % - 65.23 % and 33.63 % - 86.04 %, respectively. The grazing of microzooplankton was mainly limited by ciliates abundance. Results of grazing pressure on primary production indicated that microzooplankton played an improtant role in transmitting primary production in the north of South China Sea.
文摘This paper analyzed how nutrient silicon and water temperature influenced the variation of phytoplankton growth and the change of its assemblage structure, and probed the different characteristics of the variation of phytoplankton growth and the different profiles of the change of its assemblage structure influenced by nutrient silicon and water temperature. Taking Jiaozhou Bay for example, this paper showed the process of both the variation of phytoplankton growth and the change of its assemblage structure, unveiled the mechanism of nutrient silicon and water temperature influencing the variation of phytoplankton growth and the change of its assemblage structure, and determined that nutrient silicon and water temperature were the motive power for the healthy running of the marine ecosystem.
基金supported by the Ministy of Science and Technology survey project under contract No.2006FY220700
文摘Based on the samples collected from the Chukchi Sea during the FCNARE cruise from July to August in 1999 with the "Xuelong", the research vessel of SOA, China, the relationship between the distribution characterization of phytoplankton and environmental factors was analyzed with Primer 5.2 software. The result showed that the assemblages of phytoplankton in Chukchi Sea can be divided into three ecological groups: Arctic-boreal group, distributed mostly in northeastern ice-edge where the depth is more than 2 000 m and affected directly by Arctic Ocean; Boreal group, distributed in shelf-break ice in the center water where the depth is less 100 m; Eurythermal group, mainly distributed in the south which exchanged with North Pacific water through Bering Strait. The species diversity, cell density and distribution variability of phytoplankton among stations were great different. The range of phytoplankton density among stations was 1.6 × 10^3- 90 680.2 × 10^4 cells/m^3, and the ranges of diversity index and evenness index among stations were 0.07 - 0.87 and 0.33 - 3.82, respectively. Principal components analysis (PCA) showed that temperature and salinity had made important roles in the distribution of phytoplankton in the Chukchi Sea. Furthermore, the different influences of the variant water regimes, and the extremely dynamic physical nature of the drifting pack ice (e.g. packing, breaking up and melting ) introduce short-term variability into the water conditions that no doubt affect the phytoplankton distrubition.
基金Supported by Fishery Germplasm Conservation Project of the Ministry of Agriculture(MOA)(No.6115048)State Specific Project on Fundamental Scientific Research Financed to Public Institutes(No.2009JBFB10)~~
文摘[Objective] Surveys of phytoplankton were taken during the autumn of 2009 along Anhui-Jiangsu reaches of the Yangtze River to understand the species com- position and their spatial distributions. [Method] Phytoplankton species, their quanti- ties, biomass and the Mcnaughton's dominance indices were all measured and their spatial distribution characteristics were determined using cluster analysis. [Result] There were 27 species, belonging to 5 phyla, namely Chlorophyta, Bacillariophyta, Cyanophyta, Euglenophyta and Cryptophyta, of phytoplankton collected and identified from the surveys. Results showed that Bacillariophyta was the predominant phyto- plankton with 16 species collected which accounted for 59.3% of the total species identified. The number of species collected belonging to Chlorophyta, Cyanophyta, Cryptophyta and Euglenophyta were 6, 2, 2, and 1, accounting for 22.2%, 7.4%, 7.4% and 3.7% of the total number identified, respectively. At the species level, the predominant species were Fragilaria crotonensis, Melosira italica, Navicula crypto- cephala, Cyclotella striata and Chroomonas acuta. Phytoplankton abundance was ranging from 5.68×10^4 to 7.08×10^4 cells/L with its average of 6.01×10^4 cells/L. Phyto- plankton biomass was ranging from 30.43 to 34.73 μg/L with its average of 32.46 μg/L. Compared with the previous reports, the number of phytoplankton species was decreased but its abundance and biomass was increased along the Jiangsu reach of the Yangtze River. However, Bacillariophyta species were still the predominant species and the phytoplankton community structure had not significantly changed from the previous studies. [Conclusion] These results might be explained as that the water quality in the Yangtze River was deteriorated but had not come to the worst. The results of similarity analysis gave two clusters of phytoplankton community as Nanjing, Wuhu and Jiangyin sampling sites were clustered into one group and Tongling and Anqing were clustered into another group.
文摘Responses of Prochlorococcus (Pro), Synechococcus (Syn), pico-eukaryotes (Euk) and heterotrophic bacteria (Bact) in pelagic marine ecosystems to external nutrient perturbations were examined using nitrogen- (N), phosphorus- (P), iron- (Fe), and cobalt- (Co) enriched incubations in the South China Sea in November 1997. Variations in abundance of the 4 groups of microorganism and cellular pigment content of the autotrophs during incubation were followed by flow-cytometric measurements for seven days. During the incubation, Syn and Euk showed a relatively higher demand on Fe and N, while Pro required higher levels of Co and P. The Fe was inadequate for all the organisms in the deep euphotic zone (75 m) of the study area. The experimental results also implied that biological interaction among the organisms played a role in the community structure shift during the incubation. It seemed that besides the effects of temperature, there are some other physical and chemical limitations as well as impacts from biological interactions on Pro distribution in coast waters.
文摘Distribution of dimethylsulfide (DMS) and/or particulate dimethylsulfoniopropionate (DMSPp) concentrations in the Jiaozhou Bay, Zhifu Bay and East China Sea were investigated during the period of 1994 - 1998. Both DMS and DMSPp levels showed remarkable temporal and spatial variations. High values occurred in the coastal or shelf waters and low values in the offshore waters. The highest levels were observed in spring or summer and lowest in autumn. DMS or DMSPp distribution patterns were associated with water mass on a large geographical scale, while biological and chemical factors were more likely influential on smaller-scale variations. Diatoms could play an important role in total DMS or DMSPp abundance in coastal waters. Nitrate was found to have a two-phase relationship with DMSPp concentrations: positive when nitrate concentration was lower than 1 mumol/L, and negative when it was above. Anthropogenic factors such as sewage input and aquaculture also showed influences on DMS or DMSPp concentration.
基金Supported by Major Subject of National Science and Technology(2009ZX07317-006 )Shanghai Key Scientific and Technological Issues (062312019)~~
文摘[Objective] The aim was to carry out study on characteristics of phytoplankton and its correlation with water environment in SFTWs. [Method] Based on the pilot-scale SFTWs in Hongqiao transportation hub of Shanghai,phytoplankton's community structure,diversity index and their correlation with water purification performance were investigated. [Result] 57 species of seven phylum of phytoplankton were detected in this tested river,including 12 species of Cyanophyta,2 of Cryptophyta,10 of Bacillariophyta,1 of Xanthophyta,7 of Euglenophyta,1 of Pyrrophyta and 24 of Chlorophyta,respectively. Additionally,it was found that Cyanophyta was the dominant phytoplankton,followed by Bacillariophyta and Cyanophyta. Biological density was far more than 10×105 ind./L,thus it could be considered that the river was eutrophic. The range of Shannon-Wiener index was 0.6-2.2,Pielou index was 0.5-2.5 and Margalef index's range was 0.35-0.85,which could further prove that the water was eutrophic. The biological density and species were significantly positively correlated with temperature and N content,indicating that the absorption of N by phytoplankton was the main N-removal pathway in SFTWs. [Conclusion] This study had provided basis for the river regulation and ecological restoration.
基金National‘973’Program(2001CB409707)the Natural Science Foundation ofChina(No.40206016 and U0633007)+1 种基金the Key Program of National Natural Science Foundation of China(No.40531006)the Field Platform&Station Foundation of CAS.
文摘A algal bloom process had been simulated via field mesocosm experiment, and the change of phytoplankton assemblage of different sizes in different growing phases had been studied. Nutrients addition could promote the growth of phytoplankton In the mesocosm of Prorocentrum donghaiense (M1) and the mesocosm of natural waters (M2), and the peaks of chlorophyll a were 112.79 mg/m and 235.60 mg/m, respectively. The restraining effect of nano-phytoplankton on pico-phytoplankton growth was stronger in M2 than in M1. When nutrients were abundant, the relative growth rate of diatom was higher than that of P. donghaiense, and they reached the peak quickly and then came to die out very fast. The decreasing of Si promoted diatom bloom to die out.
基金Supported by Science and Technology Project in Anhui Province(11070303016)~~
文摘[Objective] This study aimed to investigate the dominant populations of late-summer phytoplankton and conduct comprehensive nutritional evaluation of water quality in Bailang Lake. [Method] A series of water quality survey and phytoplankton sampling was conducted in Bailang Lake in September 2011, a total of four sam- pling points were set, to detect and analyze the total nitrogen, total phosphorus, ammonia nitrogen, nitrite nitrogen, nitrate nitrogen and permanganate index in water samples and further conduct comprehensive nutritional evaluation of the water quality factors using comprehensive nutritional state index method. [Result] Water in Bailang Lake was neutral to slightly alkaline with pH of 8.57. The average water trans- parency was 0.4 m, with relatively high content of dissolved oxygen. The content of total nitrogen was relatively high of 3.043 mg/L averagely. Comprehensive nutritional evaluation showed that the water quality of Bailang Lake belonged to moderate eu- trophication. As can be seen from various comprehensive nutritional state indices TLI, the contribution of transparency, chlorophyll a and total nitrogen to the eutrophi- cation in Bailang Lake was the greatest, followed by the permanganate index and total phosphorus. Statistical analysis showed that the average weight-biomass of phy- toplankton in Bailang Lake was 6.442 mg/L, and the average was 146.46x104 individuals/ml. There were eight dominant species in Bailang Lake, including Scenedesmus, Tetraedron, Merismopedia sinica, Phormidium, Merismopedia, Tribonema, Chroomonas and Synedra. [Conclusion] This study provided data informa- tion for the environmental protection and fisheries production in Bailang Lake.