工业有机污染对城市景观水体沉积物中细菌群落的影响

Effect of industry organic pollution on bacterial community in sediment of city landscape water body

为探究工业有机污染对城市景观水体沉积物微生物多样性的影响,通过研究不同程度有机污染下沉积物细菌群落特征和多样性变化,采用有机污染指数法对沉积物污染情况进行了评价,并分析了水质、沉积物营养状况等环境因子与沉积物细菌多样性的相关性。结果表明,不同有机污染程度的水体沉积物细菌优势门类为Proteobacteria(64.39%)、Bacteroidetes(11.64%)、Firmicutes(8.80%)等。在属分类水平上,平均丰度较高的是Rhodobacter(10.33%)、Lysobacter(6.06%)、Pseudomonas(5.52%)、Acinetobacter(5.41%)、Massilia(5.04%)。细菌多样性与DO、有机质、总氮均有显著相关性。较高浓度的有机污染导致水体溶解氧和pH降低,沉积物中厌氧细菌大量繁殖,细菌总量和多样性显著下降;低浓度有机质和曝气条件有利于细菌群落多样性增加。污染发生后导致与污染物降解相关的细菌明显聚集,其中Rhodobacter、Acinetobacter、Prevotella等可能是厌氧条件下主要分解有机污染物的功能菌,Pseudomonas、Lysobacter、Massilia、Bacillus、ThioBacillus等可能是兼氧条件下主要分解有机污染物的功能菌。

To explore the effect of industry organic pollution on the microbial diversity of sediment in city lanscape water body,the characteristics and diversity of bacterial community in sediments under different degrees of organic pollution were studied by high-throughput sequencing.The organic pollution index method was used to evaluate the sediment pollution,and Pearson correlation between bacterial diversity of sediments with environmental factors such as water quality and sediment nutrient status was analyzed.The results showed that the dominant categories of bacteria were Proteobacteria(64.39%),Bacteroidetes(11.64%),and Firmicutes(8.80%).At the level of genus classification,Rhodobacter(10.33%),Lysobacter(6.06%),Pseudomonas(5.52%),Acetobacter(5.41%)and Massilia(5.04%)have the highest average abundance,but the distribution of each genus in the sample is very uneven.Bacterial diversity and abundance were significantly correlated with do,organic matter and total nitrogen.The higher concentration of organic pollution results in the decrease of dissolved oxygen and pH value in the water,the large number of anaerobic bacteria in the sediment,and the significant decrease of the total amount and diversity of bacteria;the lower concentration of organic matter and aeration conditions are conducive to the increase of the diversity of bacterial community.After the occurrence of pollution,the bacteria related to the degradation of pollutants gather obviously,among which Rhodobacter,Acinetobacter and Prevotella may be the functional bacteria that mainly decompose organic pollutants under anaerobic conditions,Pseudomonas,Lysobacter,Massilia,Bacillus and ThioBacillus may be the functional bacteria that mainly decompose organic pollutants under facultative conditions.