Using the Illumina sequencing technology, we investigated the vertical distribution of archaeal community in the sediment of Zhushan Bay of Lake Taihu, where the black bloom frequently occurred in summer. Overall, the Miscellaneous Crenarchaeotal Group (MCG), Deep Sea Hydrothermal Vent Group 6 (DHVEG-6), and Methanobacterium dominated the archaeal community. However, we observed significant difference in composition of archaeal community among different depths of the sediment. DHVEG-6 dominated in the surface layer (0–3 cm) sediment. Methanobacterium was the dominating archaeal taxa in the L2 (3–6 cm) and L3 (6–10) sediment. MCG was most abundant in the L4 (10–15 cm) and L5 (15–20 cm) sediment. Besides, DHVEG-6 was significantly affected by the concentration of total phosphorus (TP). And loss on ignition (LOI) was an important environmental factor for Methanobacterium. As the typical archaeal taxa in the surface layer sediment, DHVEG-6 and Methanobacterium might be more adapted to abundant substrate supply from cyanobacterial blooms and take active part in the biomass transformation. We propose that DHVEG-6 and Methanobacterium could be the key archaeal taxa correlated with the “black bloom” formation in Zhushan Bay.

中文翻译：

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“黑花”中沉积古生菌群落的垂直分布，扰动了太湖竹山湾。

利用Illumina测序技术，我们研究了太湖朱山湾沉积物中古生菌群落的垂直分布，该湖在夏季经常出现黑花。总体而言，杂项颅骨类（MCG），深海热液排放组6（DHVEG-6）和甲烷菌主导了古细菌群落。然而，我们观察到沉积物不同深度之间古细菌群落的组成存在显着差异。DHVEG-6在表层（0–3 cm）沉积物中占主导地位。甲烷菌是L2（3–6 cm）和L3（6–10）沉积物中主要的古细菌类群。MCG在L4（10-15厘米）和L5（15-20厘米）沉积物中最丰富。此外，DHVEG-6受到总磷（TP）浓度的显着影响。灼烧损失（LOI）是甲烷菌的重要环境因素。作为表层沉积物中典型的古细菌类群，DHVEG-6和甲烷菌可能更适应蓝藻水华提供的丰富底物，并积极参与生物量转化。我们认为，DHVEG-6和甲烷菌可能是与竹山湾“黑花”形成有关的主要古细菌类群。