School of Environment, Nanjing Normal University, Nanjing, 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing, 210023, China; Jiangsu Engineering Lab of Water and Soil Eco-remediation, Nanjing Normal University, Nanjing, 210023, China.
Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
Environ Pollut. 2022 Jun 15;303:119129. doi: 10.1016/j.envpol.2022.119129. Epub 2022 Mar 10.
Urbanization has destroyed river ecosystems, leading to eutrophication. Heavy metals are frequently observed in urban rivers, and the joint effects of eutrophication and heavy metals on microbial communities, especially on fungal communities, have not been adequately explored. In this study, we explored the effect of sediment physicochemical factors and heavy metals on the microbial diversity, community structure, and functions of bacterial and fungal communities from a black-odorous river in Wuhu, China. Twenty-four samples were collected, and the diversity and structure of fungal and bacterial communities were determined by high-throughput sequencing. Proteobacteria and Rozellomycota were the main phyla in the bacterial and fungal communities, respectively. The results showed different distribution patterns of bacterial and fungal communities along the river. Physicochemical factors and heavy metals exhibited different effects on microbial variation. Specifically, pH and Cr negatively affected bacterial α-diversity, whereas total phosphorus and Cr significantly affected fungal α-diversity. Variance partitioning analysis revealed that physicochemical factors explained more of the bacterial community structure than heavy metals (49.5% vs. 36.6%), with pH and total phosphorus being the dominant factors. Opposite patterns were observed for fungal community structure, with heavy metals contributing the most (48.0%). A similar influence pattern was observed for the predicted functions of the two communities. This study suggests that heavy metals in eutrophication rivers are essential factors that shift the microbial variation and should be considered in urban river evaluation and remediation.
城市化破坏了河流生态系统，导致富营养化。重金属经常在城市河流中被观察到，而富营养化和重金属对微生物群落的联合影响，特别是对真菌群落的影响，尚未得到充分探索。在这项研究中，我们探讨了底质理化因子和重金属对来自中国芜湖黑臭河流的细菌和真菌群落的微生物多样性、群落结构和功能的影响。共采集了 24 个样本，并通过高通量测序确定了真菌和细菌群落的多样性和结构。变形菌门和Rozellomycota 分别是细菌和真菌群落中的主要门。结果表明，细菌和真菌群落沿河流呈现不同的分布模式。理化因子和重金属对微生物的变化表现出不同的影响。具体而言，pH 和 Cr 对细菌的 α 多样性有负面影响，而总磷和 Cr 对真菌的 α 多样性有显著影响。方差分解分析表明，理化因子对细菌群落结构的解释程度高于重金属（49.5%对 36.6%），其中 pH 和总磷是主要因素。而真菌群落结构则呈现相反的模式，重金属的贡献最大（48.0%）。两个群落的预测功能也表现出相似的影响模式。本研究表明，富营养化河流中的重金属是改变微生物变化的重要因素，应在城市河流评估和修复中加以考虑。
