Community Composition and Function of Bacteria in Activated Sludge of Municipal Wastewater Treatment Plants

Abstract

Municipal wastewater treatment plants (WWTPs) use functional microorganisms in activated sludge (AS) to reduce the environmental threat posed by wastewater. In this study, Illumina NovaSeq sequencing of 16S rRNA genes was performed to explore the microbial communities of AS at different stages of the two WWTP projects in Shenzhen, China. Results showed that Proteobacteria, Bacteroidetes, Acidobacteria, Firmicutes, and Nitrospirae were the dominant phyla in all the samples, with Proteobacteria being the most abundant and reaching a maximum proportion of 59.63%. There was no significant difference in biodiversity between the two water plants, but Stage 1 and Stage 2 were significantly different. The Mantel test indicated that nitrate, total nitrogen (TN), chemical oxygen demand (COD), and nutrients were essential factors affecting the bacterial community structure. FAPROTAX analysis emphasized that the leading functional gene families include nitrification, aerobic nitrite oxidation, human pathogens, and phototrophy. This study reveals changes in the community structure of AS in different treatment units of Banxuegang WWTP, which can help engineers to optimize the wastewater treatment process.

Characterization of Microbial Communities in Wastewater Treatment Plants Containing Heavy Metals Located in Chemical Industrial Zones

“…Therefore, these dominant bacteria were thought to serve as the functional microbes for the removal of organic matter, N, and P in the XW- and SM-WWTPs. Compared with the activated sludge of other A 2 O and MBR process WWTPs, their dominant bacterial genera were Haliangium , Arcobacter , Ferruginibacter , and Cloacibacter [ 36 ], which was very different from our results. The main reasons for this discrepancy could be differences in the locations of the WWTPs and the quality of the influent.…”

“…Chloroflexi was the most important bacterial phylum for nitrite oxidation and denitrification in activated sludge [ 33 ], playing a role in the production of the filamentous scaffolding of flocs, carbohydrate breakdown, and sludge settleability [ 34 , 35 ]. In addition, Proteobacteria , Bacteroidetes , Acidobacteria , Firmicutes , and Nitrospirae were the dominant phyla at different stages of the two WWTP projects in Shenzhen, China [ 36 ], with Proteobacteria being the most abundant, which was consistent with the findings of this experiment. The differences in other dominant phyla were likely due to the different quality of the influent samples, and the inhibition of the growth of microorganisms by the HMs contained in the industrial wastewater that was used in this experiment.…”

“…In addition, some characteristic factors (nitrite, nitrate, and COD) could also affect the bacterial community [ 36 ]. TN and pH were studied in concert with the NH 4 + -N, and they played an important role in the basic activities of microorganisms.…”

Analysis of the Bacterial Biocenosis of Activated Sludge Treated with Leachate from Municipal Landfills

“…In each sample analysed, Proteobacteria was the most abundant type, which was also found in previous studies conducted on urban wastewater treatment plants [15,20,63,64]. Proteobacteria play a very important role in wastewater treatment by removing organic pollutants, nitrogen and phosphorus [15,65].…”

Remediation of low C/N wastewater by iron–carbon micro-electrolysis coupled with biological denitrification: Performance, mechanisms, and application

“…Firmicutes are Gram-negative bacteria which can degrade COD and are closely related to denitrification [32,38,39]. Xie et al [40] found that Proteobacteria, Bacteroidetes, Acidobacteria, Firmicutes, and Nitrospirae were the dominant phyla in the sludge of sewage treatment plant. This was similar to the microbial community structure in the pond, and the strains screened from the actual environment might have stronger environmental adaptability, better tolerance to the actual water body and shorten the denitrification cycle.…”