ABSTRACT

Global climate changes and anthropogenic activity greatly impact Arctic marine biodiversity including phytoplankton which contribute greatly to atmospheric oxygen production. Thus the study of microalgae has rising topicality. Class Mamiellophyceae is an important component of phototrophic picoplankton. To gain more knowledge about Mamiellophyceae distribution and diversity special studies were performed in such remote areas as the Russian Arctic seas. A metabarcoding of pico-sized Mamiellophyceae was undertaken by high-throughput sequencing of the 18S rRNA gene sequence V4 region from samples collected in July–September 2017 in the Barents, Kara and Laptev seas, and in the adjacent waters of the Norwegian Sea. Our study is the first to show that Mamiellophyceae among the summer picoplankton of Russian Arctic seas are diverse and represented by 16 algae species/phylotypes. We discovered a new candidate species of Bathycoccus assigned to a new Bathycoccus clade A—uncultured Bathycoccus Kara 2017. It was found that several Micromonas species can co-exist, with Micromonas polaris dominating north of 72°N. The presence of Ostreococcus tauri, Ostreococcus lucimarinus and Ostreococcus mediterraneus at high latitudes beyond 65°N was documented for the first time, similar to findings for some other taxa. Our results will be important for obtaining a global view of Mamiellophyceae community dynamics.

中文翻译：

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皮克大小的Mamiellophyceae和来自俄罗斯北极海和邻近水域的夏季浮游生物的新颖的Bathycoccus进化枝

摘要

全球气候变化和人为活动极大地影响了包括浮游植物在内的北极海洋生物多样性，极大地促进了大气氧的产生。因此，对微藻类的研究日益受到关注。Mamiellophyceae类是光养浮游生物的重要组成部分。为了获得有关毛状藻科分布和多样性的更多知识，在俄罗斯北极海等偏远地区进行了特殊研究。通过对2017年7月至9月在巴伦支海，卡拉海和拉普捷夫海以及在挪威海附近水域采集的样品中的18S rRNA基因序列V4区进行高通量测序，对皮克大小的拟杆菌科进行了metabarcoding。我们的研究首次表明，俄罗斯北极海夏季微型浮游植物中的藻科是多样的，并以16种藻类/系统型为代表。我们发现了一种新的候选物种红球菌被分配到一个新的Bytycoccus进化枝A-未培养的Bythycoccus Kara2017。已发现几种微单胞菌物种可以共存，其中北极微单胞菌在72°N以北占主导地位。首次记录到在超过65°N的高纬度地区，金牛粪链球菌，褐藻粪球菌和地中海嗜盐菌存在，这与其他类群的发现相似。我们的结果对于获得全球沙门氏菌群落动态的观点将是重要的。