To assess the comparability between taxonomic identification methods for phytoplankton, multiple approaches were used to characterize phytoplankton community composition within the Neuse River Estuary (NRE), North Carolina. Small subunit 18S rRNA gene sequencing and accessory pigment analysis displayed similar trends, indicating chlorophytes were the dominant microalgal group during most of the year, whereas results from microscopic cell counts, biovolume analysis and metatranscriptomics suggested diatom and dinoflagellate‐dominated communities. Spatial environmental gradients drove variation in taxonomic composition due to preferences for specific environmental conditions among different microalgal groups. Cryptophytes were a greater proportion of the phytoplankton community within high nutrient, fresher environments whereas diatoms and dinoflagellates dominated higher salinity sections of the estuary. This study provides a detailed examination of phytoplankton communities associated with environmental gradients present in the NRE. The high level of taxonomic resolution offered by DNA sequencing (i.e., species to sub‐species level) provides a better understanding of population dynamics at the base of estuarine food webs.

中文翻译：

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富营养化河口中的浮游植物组成：多种分类方法的比较和环境因素的影响。

为了评估浮游植物分类识别方法之间的可比性，使用了多种方法来表征北卡罗来纳州Neuse河河口（NRE）内的浮游植物群落组成。小亚基18S rRNA基因测序和辅助色素分析显示出相似的趋势，表明在一年中的大部分时间里，绿藻类是主要的微藻类，而从微观细胞计数，生物体积分析和超转录组学的结果表明，硅藻和鞭毛藻为主导的群落。由于不同微藻类群对特定环境条件的偏好，空间环境梯度促使分类学组成发生变化。在高养分中，隐藻植物在浮游植物群落中所占比例较高，在较新的环境中，硅藻和鞭毛藻占主导，河口盐度较高。这项研究提供了与NRE中存在的环境梯度相关的浮游植物群落的详细检查。DNA测序所提供的高分类学分辨率（即物种到亚种水平）可以更好地了解河口食物网的种群动态。