Variability in phytoplankton community structure in response to the North Atlantic Oscillation and implications for organic carbon flux
Variability in phytoplankton community structure in response to the North Atlantic Oscillation and implications for organic carbon flux
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DOI：
10.4319/lo.2012.57.6.1591
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发表时间：
2012-11
影响因子：
4.5
通讯作者：
S. Henson;R. Lampitt;D. Johns
中科院分区：
文献类型：
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作者：
S. Henson;R. Lampitt;D. Johns
北大西洋涛动(NAO)是北大西洋变化的一种主要形式，主导着大气和海洋条件。在这里，我们使用连续浮游生物记录仪数据集研究了浮游植物群落结构对NAO的响应。在东北大西洋，在涡旋之间的过渡区域，副极地或类似副热带条件的相对影响的变异性反映在物理环境中。在正NAO期间，该地区经历了类似亚极地的条件，有较强的风应力和深层混合层。相比之下，在负NAO期间，该地区转向更接近副热带的条件。在正NAO期，硅藻在浮游植物群落中占主导地位，而在负NAO期，甲藻胜过硅藻。利用豪猪深海平原时间序列站的数据，研究了深海碳通量年际变化的含义。与预期相反，当硅藻被其他功能类型的浮游植物击败时，3000米的碳通量会增加。此外，最高的碳通量与生物矿物含量的增加无关，这意味着压载在控制该地区物质流向深海方面并不起主导作用。在环流系统之间的过渡区，浮游植物种群可以改变，以响应由相反的NAO阶段引起的强迫。
The North Atlantic Oscillation (NAO) is a major mode of variability in the North Atlantic, dominating atmospheric and oceanic conditions. Here, we examine the phytoplankton community‐structure response to the NAO using the Continuous Plankton Recorder data set. In the Northeast Atlantic, in the transition region between the gyres, variability in the relative influence of subpolar or subtropical‐like conditions is reflected in the physical environment. During positive NAO periods, the region experiences subpolar‐like conditions, with strong wind stress and deep mixed layers. In contrast, during negative NAO periods, the region shifts toward more subtropical‐like conditions. Diatoms dominate the phytoplankton community in positive NAO periods, whereas in negative NAO periods, dinoflagellates outcompete diatoms. The implications for interannual variability in deep ocean carbon flux are examined using data from the Porcupine Abyssal Plain time‐series station. Contrary to expectations, carbon flux to 3000 m is enhanced when diatoms are outcompeted by other phytoplankton functional types. Additionally, highest carbon fluxes were not associated with an increase in biomineral content, which implies that ballasting is not playing a dominant role in controlling the flux of material to the deep ocean in this region. In transition zones between gyre systems, phytoplankton populations can change in response to forcing induced by opposing NAO phases.