The Strait of Malacca (SoM), the world's busiest sea-route, is increasingly polluted as the rapid develop- ment of world trades, affecting phytoplankton primary productivity therein. The variations of surface phy- ...The Strait of Malacca (SoM), the world's busiest sea-route, is increasingly polluted as the rapid develop- ment of world trades, affecting phytoplankton primary productivity therein. The variations of surface phy- toplankton biomass, size-structure and carbon fixation were investigated across the SoM during the spring period (May 4 to 9, 2011). Chlorophyll a concentration increased from 0.12 ptg/L at the northwest entrance of the SoM to a maximal 0.63 #g/L at narrowest section, and decreased to 0.10/.tg/L at the southeast entrance. Photosynthetic carbon fixation by phytoplankton coincided well with Chl a biomass, and increased from 10.8 to 22.3 pg C/(L.d), then decreased to 9.21/zg C/(L.d); while the carbon fixation rate showed an inverse pattern to the changes of Chl a, and decreased from 87.1 to 35.5 #g C/(#g Chl a.d) and increased thereafter to 95.3 btg C/(/2g Chl a.d). Picophytoplankton cells (〈3/2m) contributed to more than 60% and 50% of the total Chl a and carbon fixation at both the entry waters; while the contributions of pico-cells decreased sharply to the minimum of 18.3% and 27.5% at the narrowest part of the SoM. In particular, our results showed that the silicate concentration positively regulated Chl a biomass and carbon fixation, reflecting that the higher silicate favoured the growth of phytoplankton and thus led to higher primary production in this strait.展开更多
Vertical distributions of phytoplankton biomass, compositions and size structure were investigated during the spring-intermonsoon (April 22 to 30) of 2010 along transact 10°N of the Bay of Bengal, northern Indi...Vertical distributions of phytoplankton biomass, compositions and size structure were investigated during the spring-intermonsoon (April 22 to 30) of 2010 along transact 10°N of the Bay of Bengal, northern Indian Ocean. Surface phytoplankton biomass (Chl a) was (0.065±0.009) μg/L, being greater than 80% of which was contributed by pico-phytoplankton (〈3 μm). The Chl a concen- tration vertically increased to the maximal values at deep chlorophyll maximum (DCM) layer that shoaled eastwards from 75 to 40 m. The Chl a biomass at DCM layer generally varied between 0.2 and 0.4 μg/L, reaching the maximum of 0.56 μg/L with micro-phytoplankton cells (~20 #m) accounting for 58% and nano- (3-20μm) or pico-cells for 15% and 27%, respectively. In particular, the cells concentration coupling well with phosphate level was observed at middle layer (75-100 m) of 87° to 89°E, dominated by micro-cells diatoms (e.g., Chaetoceros atlanticus v. neapolitana, Chaetoceros femur and Pseudonitzsehia sp.) and cyanobacteria (i.e., Trichodesmium hildebrandtii), With the ceils concentration reached as high as 4.0 × 10^4 and 4.3 × 10^4 cells/L. At the rest of the trans- act however, dinoflagellates (e.g., Amphisdinium carterae and Prorocentrum sp.) were the dominant species, with the cells concentration varying from 0.3×10^3 to 6.8×10^3 cells/L. Our results also indicate that the regulation of large cells (micro-, nano-) on phytoplankton biomass merely occurred at DCM layer of the Bay.展开更多
基金The National Natural Science Foundation of China under contract Nos 41130855,41206132 and 41276162the Natural Science Foundation of Guangdong under contract No.S2011040000151+2 种基金CAS Knowledge Innovation Program under contract No.SQ201115National Project of Sciences and Technology under contract No.2008FY110100CAS Strategic Pilot Science and Technology under contract No.XDA05030403
文摘The Strait of Malacca (SoM), the world's busiest sea-route, is increasingly polluted as the rapid develop- ment of world trades, affecting phytoplankton primary productivity therein. The variations of surface phy- toplankton biomass, size-structure and carbon fixation were investigated across the SoM during the spring period (May 4 to 9, 2011). Chlorophyll a concentration increased from 0.12 ptg/L at the northwest entrance of the SoM to a maximal 0.63 #g/L at narrowest section, and decreased to 0.10/.tg/L at the southeast entrance. Photosynthetic carbon fixation by phytoplankton coincided well with Chl a biomass, and increased from 10.8 to 22.3 pg C/(L.d), then decreased to 9.21/zg C/(L.d); while the carbon fixation rate showed an inverse pattern to the changes of Chl a, and decreased from 87.1 to 35.5 #g C/(#g Chl a.d) and increased thereafter to 95.3 btg C/(/2g Chl a.d). Picophytoplankton cells (〈3/2m) contributed to more than 60% and 50% of the total Chl a and carbon fixation at both the entry waters; while the contributions of pico-cells decreased sharply to the minimum of 18.3% and 27.5% at the narrowest part of the SoM. In particular, our results showed that the silicate concentration positively regulated Chl a biomass and carbon fixation, reflecting that the higher silicate favoured the growth of phytoplankton and thus led to higher primary production in this strait.
基金The Key Innovation Group Project of Chinese Academy of Sciences under contract No.KZCX2-YW-Q07the National Natural Science Foundation of China under contract No.41130855+5 种基金the Natural Science Foundation of Guangdong under contract No.S2011040000151CAS Knowledge Innovation Program under contract No.SQ20115National Project of Sciences and Technology under contract No.2008FY110100CAS Strategic Pilot Science and Technology under contract No.XDA05030403MEL Young Scientist Visiting Fellowship of State Key Laboratory of Marine Environment ScienceXiamen University under contract No.MELRS 1006
文摘Vertical distributions of phytoplankton biomass, compositions and size structure were investigated during the spring-intermonsoon (April 22 to 30) of 2010 along transact 10°N of the Bay of Bengal, northern Indian Ocean. Surface phytoplankton biomass (Chl a) was (0.065±0.009) μg/L, being greater than 80% of which was contributed by pico-phytoplankton (〈3 μm). The Chl a concen- tration vertically increased to the maximal values at deep chlorophyll maximum (DCM) layer that shoaled eastwards from 75 to 40 m. The Chl a biomass at DCM layer generally varied between 0.2 and 0.4 μg/L, reaching the maximum of 0.56 μg/L with micro-phytoplankton cells (~20 #m) accounting for 58% and nano- (3-20μm) or pico-cells for 15% and 27%, respectively. In particular, the cells concentration coupling well with phosphate level was observed at middle layer (75-100 m) of 87° to 89°E, dominated by micro-cells diatoms (e.g., Chaetoceros atlanticus v. neapolitana, Chaetoceros femur and Pseudonitzsehia sp.) and cyanobacteria (i.e., Trichodesmium hildebrandtii), With the ceils concentration reached as high as 4.0 × 10^4 and 4.3 × 10^4 cells/L. At the rest of the trans- act however, dinoflagellates (e.g., Amphisdinium carterae and Prorocentrum sp.) were the dominant species, with the cells concentration varying from 0.3×10^3 to 6.8×10^3 cells/L. Our results also indicate that the regulation of large cells (micro-, nano-) on phytoplankton biomass merely occurred at DCM layer of the Bay.