Flow cytometric determinations of the abundance distribution picophytoplankton （i.e. Prochlorococcus spp., orange fluorescence and community structure of Svnechococcus spp. and picoeukaryotes） were used for samples ...Flow cytometric determinations of the abundance distribution picophytoplankton （i.e. Prochlorococcus spp., orange fluorescence and community structure of Svnechococcus 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 58×10^3 cells ml^-1, 0.38 to 17×10^2 cells ml^-1 and 0.42 to 26×10^2 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.展开更多
基金Supported by National Natural Science Foundation of China (No. 40821004)the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-213-3)National Basic Research Program of China (973 Program) (No. 2006CB400604)
文摘Flow cytometric determinations of the abundance distribution picophytoplankton （i.e. Prochlorococcus spp., orange fluorescence and community structure of Svnechococcus 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 58×10^3 cells ml^-1, 0.38 to 17×10^2 cells ml^-1 and 0.42 to 26×10^2 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.
