利用形态学鉴定和高通量测序技术, 对2022年5月南澳海域浮游植物群落结构进行了研究, 探讨其空间分布与环境因子的关系, 并对两种不同方法得出的结果进行了比较和讨论。根据环境因子聚类分析, 调查海域可分为近岸区域和远岸区域。通过形态学方法鉴定浮游植物5门8纲27目39科52属105种, 高通量测序鉴定出6门32纲97目155科272属 543种, 其中硅藻门(Bacillariophyta)和甲藻门(Dinophyta)为优势类群, 分别平均占形态学鉴定结果的74.54%和24.78%以及高通量测序结果的 17.52%和67.84%。形态学鉴定结果显示浮游植物丰度变化范围为0.11×10⁵~6.85×10⁵cells·L^-1, 与叶绿素a浓度分布显著相关, 浮游植物多样性指数低于高通量测序方法。两种方法得到优势种均为7种, 其中形态学鉴定结果中绝对优势种为扁面角毛藻(Chaetoceros compressus), 高通量测序鉴定结果中绝对优势种为球形异帽藻(Heterocapsa rotundata)。相关性分析结果表明, 春季影响南澳浮游植物群落结构的主要环境因子是pH、盐度和溶解态无机磷。利用形态学鉴定与高通量测序技术相结合的方法, 可以更全面、更准确地描述浮游植物群落结构及多样性。

The structure of phytoplankton community was investigated based on morphological identification and high-throughput sequencing in the Nan’ao waters in May 2022. The spatial distribution of phytoplankton in relation to environmental factors was explored and results from two different methods were also compared and discussed. According to the cluster analysis of environmental factors, the survey area can be divided into nearshore area and offshore area. Totally, 105 species belong to 52 genera, 39 families, 27 orders, 8 orders, 5 phyla were morphological identified, while 543 species in 6 phyla, 32 orders, 97 families, 155 families, 272 genera through high-throughput sequencing were identified. Bacillariophyta and Dinophyta were the main groups, composing 74.54% and 24.78% through microscopic identification, and 17.52% and 67.84% through high-throughput sequencing, respectively. The abundance of phytoplankton identified by morphology ranged from 0.11×10⁵ to 6.85×10⁵ cells·L^-1, which was significantly correlated with the distribution of chlorophyll a concentration, and the phytoplankton diversity index was lower than that of the high-throughput sequencing method. 7 dominant species were obtained by both methods, of which the absolutely dominant specie in the morphological identification results was Chaetoceros compressus, and the absolute dominant specie in the high-throughput sequencing identification results was Heterocapsa rotundata. Correlation analysis showed that the main environmental factor affecting phytoplankton community structure in Nan’ao in spring was pH, salinity and DIP (dissolved inorganic phosphorus). Using the combination of morphological identification and high-throughput sequencing technology, the structure and diversity of the phytoplankton community can be described more comprehensively and accurately.