Papers by Keyword: Microbial Community Structures

Abstract: PCR-DGGE was applied to analyze the relationship between pH and the microbial community structure of Sequence Batch Biofilm Reactor (SBBR) autotrophic nitrogen removal process. The reactor was possessed of a high nitrogen removal efficiency at pH=8.0 where the similarity of microbial community structure between active sludge and biofilm samples was the lowest about 84.6% and the richness of bacterial community was the most abundant in biofilm compared with other pH conditions. pH=7.0 was good for the microbes in active sludge but unfavorable for anaerobic bacteria. At pH=9.0, the effects were presented with both bacterial activities and microbial community structure and when pH=6.0 the amount of microbial types dramatically dropped

Abstract: The effects of Hg²⁺ on microbial community structures of aerobic activated sludge were investigated by nested PCR-DGGE techniques. The results showed that the microbial community of each group might have obvious change compared with the group without Hg²⁺ in the inflow, especially when the Hg²⁺ concentration was 46.87mg/L in the inflow, and the microbial community changed obviously with the extend of operation time. The variance of microbial species become obvious in each activated sludge group with the extend of operation time. Compared with the group without Hg²⁺ in the inflow, the dominant microbial species of each activated sludge group changed, and the dominant microbial species of the group whose concentration of Hg²⁺ increased gradually in the inflow had the biggest changes after 60 days. Hg²⁺ in the inflow may stimulate the growth of Actinomycetes after an operation period of 30 days.