Abstract Marine picoplankton, including prokaryotic and eukaryotic picoplankton, drive many biogeochemical processes, such as carbon, nitrogen and sulfur cycles, making them crucial to the marine ecosystem. Despite the fact that picoplankton is prevalent, its diversity and spatial distribution from the Straits of Malacca (SM) to the South China Sea (SCS) remain poorly investigated. This work explores the phylogenetic diversity and community structure of picoplankton in relation to environmental factors from the SM to the SCS. To this end, the Illumina MiSeq sequencing technique was applied to 16S and 18S rRNA genes. The results showed significant differences in the dynamics of picoplankton between the open sea and the strait region. Proteobacteria and Cyanobacteria constituted a larger part of the prokaryotic group. Within Cyanobacteria, the abundance of Prochlorococcus in the open sea was significantly higher than that of Synechococcus, while the opposite trend was observed in the strait. Dinoflagellata, Cnidaria, Retaria, Tunicata, and Arthropoda dominated among the eukaryotic taxa. High-throughput sequencing data indicated that salinity, temperature and NO2-N were the key factors determining the prokaryotic community structure, while temperature and dissolved oxygen determined the eukaryotic community structure in the studied region. The network analysis demonstrated that the cooperation and competition were also important factors affecting the picoplankton community.

中文翻译：

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从马六甲海峡到南海的微型浮游生物群落的多样性和生物地理学

摘要 海洋微型浮游生物，包括原核和真核微型浮游生物，驱动着许多生物地球化学过程，如碳、氮和硫循环，使它们对海洋生态系统至关重要。尽管微型浮游生物很普遍，但其从马六甲海峡 (SM) 到南海 (SCS) 的多样性和空间分布仍未得到很好的研究。这项工作探讨了与从 SM 到 SCS 的环境因素相关的微型浮游生物的系统发育多样性和群落结构。为此，将 Illumina MiSeq 测序技术应用于 16S 和 18S rRNA 基因。结果表明，公海和海峡地区之间的微型浮游生物动态存在显着差异。Proteobacteria 和Cyanobacteria 构成了原核生物群的较大部分。在蓝藻中，公海中原绿球藻的丰度明显高于聚球藻，而海峡中则呈相反趋势。在真核生物分类群中，甲藻、刺胞动物、网纹动物、突尼斯动物和节肢动物占主导地位。高通量测序数据表明，盐度、温度和NO2-N是决定原核生物群落结构的关键因素，而温度和溶解氧决定了研究区域的真核生物群落结构。网络分析表明，合作与竞争也是影响微型浮游生物群落的重要因素。和节肢动物在真核生物分类群中占主导地位。高通量测序数据表明，盐度、温度和NO2-N是决定原核生物群落结构的关键因素，而温度和溶解氧决定了研究区域的真核生物群落结构。网络分析表明，合作与竞争也是影响微型浮游生物群落的重要因素。和节肢动物在真核生物分类群中占主导地位。高通量测序数据表明，盐度、温度和NO2-N是决定原核生物群落结构的关键因素，而温度和溶解氧决定了研究区域的真核生物群落结构。网络分析表明，合作与竞争也是影响微型浮游生物群落的重要因素。