Dynamics of Primary Productivity and Oceanographic Parameters under Influence of the Amazon River Plume  

作　　者：Amanda Otsuka Fernando Feitosa Moacyr Araújo Dóris Veleda Maria da Gloria Silva Cunha Nathalie Lefévre Felipe Gaspar Manuel Flores Montes Gislayne Borges Carlos Noriega 

机构地区：[1]Department of Oceanography, Federal University of Pernambuco, Recife, Brazil [2]IRD-LOCEAN, Sorbonne Universités (Université Pierre et Marie Curie-CNRS-MNHN), Paris, France

出　　处：《Open Journal of Ecology》2018年第11期590-606,共17页生态学期刊（英文）

摘　　要：The watershed of the Amazon River discharges about 120,000 m3·s-1?of freshwater into the adjacent platform and oceanic region. The aim of this work was to analyze the distribution of oceanographic parameters, chlorophyll a and primary productivity under the influence of the Amazon River plume, during the period of greatest extension of the Amazon plume. Collections were carried out in September 14 in 16 stations including continental platform and oceanic region. It was possible to observe superficial currents along the coast in the northwest direction, but with less intensity and currents with greater speeds towards the east due to the North Brazil Current retroflexion at this time of the year, transporting the plume to the central Atlantic Ocean. The spatial influence of the plume was observed in the salinity, which ranged from 28 to 36.75, although the high precipitation in the region may also have contributed as a source of freshwater. However, the sampled region showed strong negative linear correlation of silicate, chlorophyll a and primary productivity with salinity. The primary productivity values ranged from 0.04 to 18.81 mg C m-3?day-1, whereas chlorophyll a concentrations ranged from 0.15 mg·m-3?to 1.83 mg·m-3, decreasing their values as they move away from the coast. The Amazon River plume can reach and influence the oceanographic and biological parameters in a large area of this oligotrophic region. However, the results also suggest that the export of material from the adjacent coastal region is another determinant of the region’s productivity.The watershed of the Amazon River discharges about 120,000 m3·s-1?of freshwater into the adjacent platform and oceanic region. The aim of this work was to analyze the distribution of oceanographic parameters, chlorophyll a and primary productivity under the influence of the Amazon River plume, during the period of greatest extension of the Amazon plume. Collections were carried out in September 14 in 16 stations including continental platform and oceanic region. It was possible to observe superficial currents along the coast in the northwest direction, but with less intensity and currents with greater speeds towards the east due to the North Brazil Current retroflexion at this time of the year, transporting the plume to the central Atlantic Ocean. The spatial influence of the plume was observed in the salinity, which ranged from 28 to 36.75, although the high precipitation in the region may also have contributed as a source of freshwater. However, the sampled region showed strong negative linear correlation of silicate, chlorophyll a and primary productivity with salinity. The primary productivity values ranged from 0.04 to 18.81 mg C m-3?day-1, whereas chlorophyll a concentrations ranged from 0.15 mg·m-3?to 1.83 mg·m-3, decreasing their values as they move away from the coast. The Amazon River plume can reach and influence the oceanographic and biological parameters in a large area of this oligotrophic region. However, the results also suggest that the export of material from the adjacent coastal region is another determinant of the region’s productivity.

关 键 词：AMAZON River PLUME CONTINENTAL SHELF OCEANIC Region Environmental Variables PHYTOPLANKTON Biomass Primary Productivity 

分 类 号：R73[医药卫生—肿瘤]