Characterizing ecological relationships between viruses, bacteria and phytoplankton in the ocean is critical to understanding the ecosystem; however, these relationships are infrequently investigated together. To understand the dynamics of microbial communities and environmental factors in harmful algal blooms (HABs), we examined the environmental factors and microbial communities during Akashiwo sanguinea HABs in the Jangmok coastal waters of South Korea by metagenomics. Specific bacterial species showed complex synergistic and antagonistic relationships with the A. sanguinea bloom. The endoparasitic dinoflagellate Amoebophrya sp. 1 controlled the bloom dynamics and correlated with HAB decline. Among nucleocytoplasmic large DNA viruses (NCLDVs), two Pandoraviruses and six Phycodnaviruses were strongly and positively correlated with the HABs. Operational taxonomic units of microbial communities and environmental factors associated with A. sanguinea were visualized by network analysis: A. sanguinea–Amoebophrya sp. 1 (r = .59, time lag: 2 days) and A. sanguinea–Ectocarpus siliculosus virus 1 in Phycodnaviridae (0.50, 4 days) relationships showed close associations. The relationship between A. sanguinea and dissolved inorganic phosphorus relationship also showed a very close correlation (0.74, 0 day). Microbial communities and the environment changed dynamically during the A. sanguinea bloom, and the rapid turnover of microorganisms responded to ecological interactions. A. sanguinea bloom dramatically changes the environments by exuding dissolved carbohydrates via autotrophic processes, followed by changes in microbial communities involving host‐specific viruses, bacteria and parasitoids. Thus, the microbial communities in HAB are composed of various organisms that interact in a complex manner.

中文翻译：

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放大赤石红藻（Dinophyta）水华藻类中海洋微生物群落的动态

表征海洋中病毒、细菌和浮游植物之间的生态关系对于了解生态系统至关重要；然而，这些关系很少被一起研究。为了了解有害藻华 (HABs) 中微生物群落和环境因素的动态，我们通过宏基因组学检查了韩国 Jangmok 沿海水域的Akashiwo sanguinea HABs 期间的环境因素和微生物群落。特定的细菌种类与A. sanguinea水华表现出复杂的协同和拮抗关系。内寄生甲藻变形虫sp。1控制开花动态并与HAB下降相关。在核质大 DNA 病毒 (NCLDVs) 中，两种潘多拉病毒和六种藻类病毒与 HAB 呈强正相关。通过网络分析可视化与A. sanguinea相关的微生物群落和环境因素的操作分类单位： A. sanguinea – Amoebophrya sp。1 ( r  = .59, 时间滞后: 2 天) 和A. sanguinea – Ectocarpus silculosus病毒 1 在藻类病毒科 (0.50, 4 天) 的关系显示出密切的关联。A. sanguinea之间的关系与溶解无机磷的关系也呈现出非常密切的相关性（0.74，0天）。在A. sanguinea开花期间，微生物群落和环境发生动态变化，微生物的快速更新对生态相互作用作出反应。A. sanguinea水华通过自养过程渗出溶解的碳水化合物来显着改变环境，随后微生物群落发生变化，包括宿主特异性病毒、细菌和寄生蜂。因此，HAB 中的微生物群落由以复杂方式相互作用的各种生物体组成。