Assessment of Changes in Microbial Communities in Different Operational Units from a Wastewater Treatment Plant

Abstract

Microbial communities in wastewater play an important role in treatment, and especially microbial community composition and changes have great influence on biological treatment. In these cases, monitoring and evaluating the changes with practical methods becomes important. Ecoplates may be an effective and quick method for assessing microbial activity. Therefore, we observed, with Ecoplates, the microbial community function of different operational units from wastewater treatment plants. Wastewater and sludge samples used in the study were taken from different units of a sewage treatment plant located in the Eskisehir in two different time intervals. Changes in wastewater samples' metabolic diversity and microbial activity were evaluated. High similarity rates were obtained from samples, as indicated by the diversity indices and average well color development (AWCD) values. A return activated sludge pump and anaerobic digestion unit were highly active in the community. Low substrate usage rates were observed in the secondary classifier unit and the lowest used substrate was 2-hydroxybutyric acid from the carboxylic acid group. The most actively used substrates were from the carbohydrate group substrates. These results refer to the degradation capacity. In addition, results showed that sampling intervals and operational conditions caused changes in the functional diversity of communities. This study allowed us to gather general information about microbial community structures in different operational units of wastewater treatment systems. The results obtained from the study showed that this method is useful for monitoring the treatment process, bacterial changes, and operational parameters.