Responses of microbial abundance and enzyme activity in integrated vertical-flow constructed wetlands for domestic and secondary wastewater

Abstract

Although micro-organisms play a significant role in pollutant removal in constructed wetlands, little is known on the effect of wastewater-quality properties on microbial characteristics. In this study, two groups of integrated vertical-flow constructed wetland microcosms were applied to treat synthetic domestic wastewater and synthetic secondary effluent. The effects of wastewater-quality properties on microbial features were assessed. Results showed that higher values of microbial indicators were observed in the systems with domestic wastewater and in down-flow cells. Redundancy analysis revealed that organic matter concentration and temperature were two critical determinants influencing the microbial features.

Keywords:

• Integrated vertical-flow constructed wetlands (IVCWs)
• Domestic wastewater (DW)
• Secondary wastewater (SW)
• Microbes
• Enzyme activities
• Water-quality properties

Acknowledgments

This work was supported by grants from Key Project of the National Twelfth-Five Year Research Program of China (2012BAD25B05-02), Major Science and Technology Program for Water Pollution Control and Treatment (2011ZX07303-001), National Natural Science Foundation of China (51179184, 51408593, 41272272).