Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Sci Total Environ. 2020 Oct 15;739:140062. doi: 10.1016/j.scitotenv.2020.140062. Epub 2020 Jun 8.
In aquatic ecosystems, water microbial communities can trigger the outbreak or decline of cyanobacterial blooms. However, the microbiological drivers of Microcystis decomposition in reservoirs remain unclear. Here, we explored the bacterial community metabolic profile and co-occurrence dynamics during Microcystis decomposition. The results showed that the decomposition of Microcystis greatly altered the metabolic characteristics and composition of the water bacterial community. Significant variations in bacterial community composition were observed: the bacterial community was mainly dominated by Proteobacteria, Actinobacteria, Planctomycetes, and Bacteroidetes during Microcystis decomposition. Additionally, members of Exiguobacterium, Rhodobacter, and Stenotrophomonas significantly increased during the terminal stages. Dissolved organic matters (DOM) primarily composed of fulvic-like, humic acid-like, and tryptophan-like components, which varied distinctly during Microcystis decomposition. Additionally, the metabolic activity of the bacterial community showed a continuous decrease during Microcystis decomposition. Functional prediction showed a sharp increase in the cell communication and sensory systems of the bacterial communities from day 12 to day 22. Co-occurrence networks showed that bacteria responded significantly to variations in the dynamics of Microcystis decomposition through close interactions between each other. Redundancy analysis (RDA) indicated that Chlorophyll a, nitrate nitrogen (NO-N), dissolved oxygen (DO), and dissolved organic carbon (DOC) were crucial drivers for shaping the bacterial community structure. Taken together, these findings highlight the dynamics of the water bacterial community during Microcystis decomposition from the perspective of metabolism and community composition, however, further studies are needed to understand the algal degradation process associated with bacteria.
在水生生态系统中，水微生物群落可以引发或减少蓝藻水华的爆发。然而，水库中微囊藻分解的微生物驱动因素仍不清楚。在这里，我们探索了微囊藻分解过程中细菌群落代谢谱和共生动态。结果表明，微囊藻的分解极大地改变了水细菌群落的代谢特征和组成。细菌群落组成发生了显著变化：在微囊藻分解过程中，细菌群落主要由变形菌门、放线菌门、浮霉菌门和拟杆菌门主导。此外，极端小球菌属、红杆菌属和寡养单胞菌属的成员在末期显著增加。溶解有机物（DOM）主要由富里酸类似物、腐殖酸类似物和色氨酸类似物组成，在微囊藻分解过程中变化明显。此外，细菌群落的代谢活性在微囊藻分解过程中呈持续下降趋势。功能预测显示，从第 12 天到第 22 天，细菌的细胞通讯和感官系统急剧增加。共生网络表明，细菌通过彼此之间的密切相互作用对微囊藻分解动态的变化做出了显著响应。冗余分析（RDA）表明叶绿素 a、硝酸盐氮（NO-N）、溶解氧（DO）和溶解有机碳（DOC）是塑造细菌群落结构的关键驱动因素。总之，这些发现从代谢和群落组成的角度揭示了微囊藻分解过程中水体细菌群落的动态，但需要进一步研究来了解与细菌相关的藻类降解过程。
