Abstract

Picophytoplankton abundance, biomass, and chlorophyll a concentration as well as contribution of picoalgae to total chlorophyll a, and species composition of phototrophic picoeukaryotes (cells size less than 3 µm) were studied in Blagopoluchia Bay (Novaya Zemlya archipelago) and the northwestern part of the Kara Sea in September 2017. In the Bay, the highest picophytoplankton abundance and biomass were found in the surface layer and averaged 0.75 × 10⁹ cell/m³ and 1.49 mg С/m³ respectively. In the northwestern part of the Kara Sea, the highest abundance and biomass of picophytoplankton were observed in the 8 m layer and were 2.29 × 10⁹ cells/m³ and 2.76 mg С/m³ respectively. The contribution of picophytoplankton to total chlorophyll a concentration varied from 12 to 24% in the Bay and reached 46% in the Kara Sea. The Illumina sequencing of the V4 region of 18S rRNA gene revealed eight classes of phototrophic picoeukaryotes. Mamiellophyceae dominated in the number of reads. Arctic endemic (Micromonas polaris) and widespread (Bathycoccus prasinos) species were revealed in both studied areas.

中文翻译：

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Blagopoluchia湾（Novaya Zemlya群岛）和卡拉海附近的浮游植物

摘要

在Blagopoluchia湾（Novaya Zemlya群岛）和西北部地区研究了浮游藻的丰度，生物量和叶绿素a的浓度，以及微藻对总叶绿素a的贡献，以及光养性微核真核生物（细胞大小小于3 µm）的物种组成。 2017年9月在卡拉海。在海湾，表层浮游藻的丰度和生物量最高，平均分别为0.75×10 ⁹细胞/ m ³和1.49 mgС/ m ³。在卡拉海西北部，在8 m层中观察到了浮游浮游生物的最高丰度和最大生物量，为2.29×10 ⁹细胞/ m ³和2.76 mgС/ m ³。在海湾中，浮游植物对总叶绿素a浓度的贡献在海湾地区从12％到24％不等，在卡拉海达到46％。Illumina对18S rRNA基因V4区的测序显示出八类光养性微核生物。念珠菌科占主导地位。在两个研究地区都发现了北极特有种（Micromonas polaris）和广泛种（Bathycoccus prasinos）。