Microbial abundance and community in constructed wetlands planted with Phragmites australis and Typha orientalis in winter

Abstract

In winter, the withering of plants in constructed wetlands (CWs) limits the removal of pollutants by plants. It is prospective to improve performance of CWs through targeted transformation of the microbial abundance and community. This research characterized the purification performance of CWs planted with Phragmites australis (P. australis, PA) and Typha orientalis (T. orientalis, TO) and those in the unplanted constructed wetland (CT, control). PA showed some superiority in the removal rates of COD and NH₄⁺-N (42.06% ± 4.25% and 70.51% ± 1.46%, respectively). The 16S rRNA gene copy numbers (7.60 ± 0.57 × 10⁴ copies/g) and the ammonia oxygen bacteria (5.30 ± 0.06 × 10³ copies/g) were the highest in PA. In microbial structure, compared with TO and CT, in addition to common microorganisms that can remove contaminants, many specific functional genera were detected in PA (Rhodobacter, Catellibacterium, Hydrogenophaga, Geothrix and Aeromonas), which promoted the removal of NH₄⁺-N and COD.

Novelty statement

The microbial abundance and communities were characterized in CWs with different plant species during winter. Better removal efficiency with high microbial abundance and diversified microbial community were found in CWs planted with Phragmites australis. This study confirmed that in winter, withered plants in CWs can effectively remove NH₄⁺-N and COD by affecting microbial abundance and community structure.

Keywords:

• Constructed wetland
• pollutant removal
• winter

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Some or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Nos. 51608315 and 51708340], International Postdoctoral Exchange Fellowship Program [No. 20180063], Special Financial Grant from the China Postdoctoral Science Foundation [No. 2015T80738], and National Major Science and Technology Program for Water Pollution Control and Treatment [2017ZX07101001]. Thanks to Chengxiu Lu for the instrument technical support in this study.