Estimating the carbon flux through main phytoplankton groups in the northwestern Mediterranean
Estimating the carbon flux through main phytoplankton groups in the northwestern Mediterranean
复制标题
估算地中海西北部主要浮游植物群的碳通量
DOI：
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发表时间：
2005
期刊：
影响因子：
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通讯作者：
M. Estrada
中科院分区：
文献类型：
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作者：
M. Latasa;X. Morán;R. Scharek;M. Estrada
我们在2000年6月在地中海西北海洋中进行了稀释实验和一级生产测量，以量化碳（C）通过浮游植物组的碳（C）通量来通过其色素标记来区分稀释液。高压液相色谱（HPLC）。平均产量为4.99毫克C M -3 D -1总浮游植物的68％的平均生长速率为0.89 d -1。硅藻藻类的生长速率最低，但养分的孵化表明，这些速率是营养的限制，尽管对每个绿色藻类的比较最为严重c融合率和CHL A合成速率允许估计研究区域中新生产的有机物的c：Chl a比为47（g：g）。估计C通过不同的浮游植物组，由于其高增长率，与生物量的贡献相比，硅藻在C通量中起着不成比例的作用。
We performed dilution experiments and primary production measurements in surface waters during a cruise in the northwestern Mediterranean Sea in June 2000 to quantify the carbon (C) flux through phytoplankton groups that can be distinguished by their pigment markers. Pigments in the dilution experiments were measured by highpressure liquid chromatography (HPLC). Pigment per cell and synthesis rates of photoprotectant versus light‐harvesting pigments indicated that cells did not undergo photoacclimation during the 24‐h dilution experiments. Mean chlorophyll a (Chl a) concentration was 0.128 mg m−3, and mean primary production was 4.99 mg of C m−3 d−1. Prymnesiophyceae contributed 51% of the total Chl a, green algae 21%, diatoms 13%, cyanobacteria 6%, and Pelagophyceae and Dinophyceae 4% each. Size fractionation showed that 68% of total phytoplankton were <5 µm. A mean growth rate of 0.89 d−1 was completely offset by a mean grazing rate of 1.01 d−1. Growth and mortality were also balanced for the individual phytoplankton groups, with highest rates for diatoms and lowest for green algae. Despite the high growth rates measured, nutrient‐amended incubations showed that these rates were nutrient limited, although to a different extent for each group. Green algae experienced the most severe limitation and cyanobacteria the least. The comparison of C incorporation rates and Chl a synthesis rates permitted the estimation of a C: Chl a ratio of 47 (g : g) for newly produced organic matter in the study area. This value, corrected for the different degree of nutrient limitation, was used to estimate the C flow through the different phytoplankton groups. Because of their high growth rates, diatoms played a disproportionate role in the C flux compared to their biomass contribution.