Oceanic Fronts Structure Phytoplankton Distributions in the Central South Indian Ocean
Oceanic Fronts Structure Phytoplankton Distributions in the Central South Indian Ocean
复制标题
南印度洋中部的海洋锋面结构浮游植物分布
DOI：
10.1029/2021jc017594
复制
发表时间：
2022-01-01
影响因子：
3.6
通讯作者：
Xing, Xiaogang
中科院分区：
文献类型：
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作者：
Guo, Mingxian;Xiu, Peng;Xing, Xiaogang
在南印度洋（SIO），在中尺度反气旋涡旋核中经常观察到高表面叶绿素浓度。然而，亚中尺度动力学在调节该地区浮游植物分布中的作用在很大程度上仍然未知。利用生物地球化学- argo浮标和高分辨率模型，我们发现在锋面区域叶绿素浓度明显升高，并且该锋面区域的深度积分叶绿素浓度可能高于反气旋涡核。亚中尺度锋生可以垂直注入养分，促进锋区浮游植物生长。锋面动力学倾向于促进硅藻等大型浮游植物的生长，从而增加硅藻的含量。在整个中央SIO中，浮游植物组成指数与锋生之间存在显著的相关性。而浮游植物总生物量与锋生的相关性不显著。这些结果表明，锋面动力学在构造SIO中部浮游植物分布中的复杂作用。
In the South Indian Ocean (SIO), high surface chlorophyll concentrations are often observed in mesoscale anticyclonic eddy cores. Yet the role of submesoscale dynamics in modulating phytoplankton distributions remains largely unknown in the region. By using a biogeochemical-Argo float and a high-resolution model, we show that elevated chlorophyll concentrations were evident in a frontal region, and the depth-integrated chlorophyll in this frontal region can be higher than that in the anticyclonic eddy core. Submesoscale frontogenesis was shown to inject nutrients vertically and enhance phytoplankton growth in the frontal region. Frontal dynamics tend to facilitate large phytoplankton such as diatom growth, which consequently increases diatom fraction. Over the entire central SIO, we found a significant correlation between the phytoplankton composition index and frontogenesis. However, the correlation between total phytoplankton biomass and frontogenesis was not significant. These results demonstrate the complex role of frontal dynamics in structuring phytoplankton distributions in the central SIO.