To further understand the effect of Kuroshio intrusion on phytoplankton community structure in the northeastern South China Sea (NSCS, 14°-23°N, 114°-124°E), one targeted cruise was carried out from July to August, 2017. A total of 79 genera and 287 species were identified, mainly including Bacillariophyta (129 species), Pyrrophyta (150 species), Cyanophyta (4 species), Chrysophyta (3 species) and Haptophyta (1 species). The average abundance of phytoplankton was 2.14×10³ cells/L, and Cyanobacterium was dominant species accounting for 86.84% of total phytoplankton abundance. The abundance and distribution of dominant Cyanobacterium were obviously various along the flow of the Kuroshio, indicating the Cyanobacterium was profoundly influenced by the physical process of the Kuroshio. Therefore, Cyanobacterium could be used to indicate the influence of Kuroshio intrusion. In addition, the key controlling factors of the phytoplankton community were nitrogen, silicate, phosphate and temperature, according to Canonical Correspondence Analysis. However, the variability of these chemical parameters in the study water was similarly induced by the physical process of circulations. Based on the cluster analysis, the similarity of phytoplankton community is surprisingly divided by the regional influence of the Kuroshio intrusion, which indicated Kuroshio intrusion regulates phytoplankton community in the NSCS.

中文翻译：

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黑潮入侵对南海东北部浮游植物群落的深远影响

为了进一步了解黑潮入侵对南海东北部（NSCS，14°-23°N，114°-124°E）浮游植物群落结构的影响，2017年7月至2017年8月进行了一次有针对性的巡航。总共鉴定到79属和287种，主要包括芽孢杆菌（129种），焦斑藻（150种），蓝藻（4种），金藻（3种）和七叶草（1种）。浮游植物的平均丰度为2.14×10 ³细胞/ L，蓝藻是优势种，占浮游植物总丰度的86.84％。优势蓝藻的丰富度和分布沿黑潮的流动明显不同，表明蓝藻的存在受到黑潮物理过程的深刻影响。因此，蓝细菌可以用来表明黑潮入侵的影响。此外，根据规范对应分析，浮游植物群落的关键控制因素是氮，硅酸盐，磷酸盐和温度。但是，研究水中这些化学参数的变化是由循环的物理过程类似地引起的。基于聚类分析，浮游植物群落的相似性被黑潮入侵的区域影响令人惊讶地划分，这表明黑潮入侵调节了NSCS中的浮游植物群落。