不同季节的微生物结构对垃圾渗滤液处理影响

Effects of microbial structure on landfill leachate treatment in different seasons

为了解不同季节下垃圾渗滤液处理池中微生物结构对水质处理效果的影响,在夏季(27.6±0.8)℃和冬季(12.4±1.1)℃分别从柳州某垃圾渗滤液污水处理厂的两级硝化和反硝化池中取样,利用高通量测序分析不同季节的微生物菌落结构。结果表明,温度是影响该系统中细菌微生物群落结构的主要因素,不同季节的微生物多样性具有显著性差异,夏季的物种丰富度和物种多样性明显高于冬季,在相关优势物种丰度上也具有显著差异性,如陶厄氏菌属(Thauera)在夏季的物种丰度明显小于冬季,而甲烷食甲基菌属(Methanomethylovorans)和懒小杆属(Ignavibacterium)在夏季的物种丰度大于冬季。物种聚类热图和主成分分析(PCA)结果显示:反应池中的物种在空间水平上的差异较小,温度主导反应池中细菌微生物组成和结构;但尽管微生物群落结构有显著差异,反应池在不同季节对垃圾渗滤液中的污染物去除效果上并无显著差别。上述结果表明,尽管温度变化导致垃圾渗滤液污水处理系统中的群落结构有较大季节性差异,但不同季节的微生物群落功能类似,因此不同季节下垃圾渗滤液生物处理可保持稳定,这可为垃圾渗滤液运行管理提供理论依据。

Samples were collected from the two-stage nitrification and denitrification tanks of a landfill leachate sewage treatment plant in Liuzhou at(27.6 ± 0.8) ℃ in summer and(12.4 ± 1.1) ℃ in winter so as to investigate the influence of microbial structure in the landfill leachate treatment tank on water quality treatment effect in different seasons. High-throughput sequencing was used to analyze the structure of microbial colonies in different seasons.The results showed that temperature was the main factor affecting the structure of bacterial microbial community in the system;there were significant differences in microbial diversity in different seasons with the richness and diversity in summer significantly higher than those in winter;there were also significant differences in the abundance of related dominant species;the species abundance of Thauera in summer was significantly lower than that in winter, while the species abundance of Methanomethylovorans and Ignavibacterium in summer was higher than that in winter. Species clustering heat map and principal component analysis(PCA)showed that the spatial differences of species in the reaction pool were small;and the composition and structure of bacterial microbes in the reaction pool were dominated by temperature;however, despite the significant differences in microbial community structure, there was no significant difference in the removal efficiency of pollutants from landfill leachate in different seasons. The above results indicated that although the microbial community structure in landfill leachate wastewater treatment system has great seasonal differences due to temperature changes, the microbial community functions are similar in different seasons;therefore, biological treatment of landfill leachate can maintain stable in different seasons. This can provide the theoretical basis for the operation and management of landfill leachate.