游离氨对强化生物除磷系统除磷效能及菌群结构的影响

为探究游离氨(FA)影响强化生物除磷(EBPR)系统除磷效能的生物学机制,采用SBR反应器,以EBPR系统的活性污泥为研究对象,探究了FA浓度分别为0,0.2,1,4,10,15,25,50 mg/L对EBPR系统除磷效能及菌群结构的影响。结果显示,FA浓度为0.2 mg/L时,对EBPR系统除磷产生促进作用,当FA浓度为1~50 mg/L时,对EBPR系统除磷产生抑制作用;门水平下,变形杆菌门Proteobacteria的丰度随着FA浓度的升高而升高;纲水平下,γ-变形菌纲Gammaproteobacteria的丰度与FA浓度呈正相关;属水平下,聚磷菌Ca. Accumulibacter与 Tetrasphaera相比,Tetrasphaera的丰度变化趋势更符合FA对除磷性能的影响;LEfSe分析显示低、中、高浓度样品的微生物标记物分别为绿弯菌门Chloroflexi、拟杆菌门Bacteroidetes及β-变形菌纲Betaproteobacteriales。研究结果明确了FA对 EBPR 系统影响的过程,加深了对EBPR系统除磷过程菌群结构的认识,可为深入研究生物除磷的抑制机理提供借鉴。

EFFECT OF FREE AMMONIA ON PHOSPHORUS REMOVAL EFFICIENCY AND MICROBIAL COMMUNITY STRUCTURE IN AN EBPR SYSTEM

Based on 16S rRNA genes-Illumina MiSeq high-throughput sequencing, this study aimed to investigate the effects of FA concentrations of 0, 0.2, 1, 4, 10, 15, 25, 50 mg/L on phosphorus removal efficiency and bacterial community structure of an EBPR system. Results indicated that when the concentration of FA was 0.2 mg/L, it promoted the phosphorus removal of the EBPR system; and when the concentration of FA was 1~50 mg/L, it inhibited the phosphorus removal of the EBPR system. The relative abundance of Proteobacteria increased with the increase of FA concentration. The relative abundance of Gammaproteobacteria was positively correlated with the FA concentration at the class level. At the genus level, the relative abundance of Tetrasphaera was more consistent with the effect of FA on phosphorus removal performance than Ca. Accumulibacter. LEfSe analysis showed that the biomarkers of Low, Mid and High were Chloroflexi, Bacteroidetes and Betaproteobacteriales, respectively. This study clarified the process of the effect of FA on the EBPR system, deepened the understanding of the bacterial community structure during the phosphorus removal process of the EBPR system, and provided a reference for the in-depth study of the inhibition mechanism of biological phosphorus removal.