Mangrove plants improve predominant microbiota in constructed wetlands for wastewater treatment

Background: Two wetlands planted with Kandelia candel and Aegiceras corniculatum and one wetland without plantation were constructed for stable wastewater treatment since 2005. The impact of mangrove plants on the microbiota of wetlands was studied due to their higher efficiency of wastewater treatment. Results Microbiota of each wetland were explored through high-throughput sequencing and their relationships were predicted based on spearman metrics. Planted wetlands had higher microbial diversities and more similar microbial communities. Five phyla were significantly enriched in planted wetlands, including Acidobacteria, Nitrospirae, Actinobacteria, Gemmatimonadetes and Elusimicrobia. Twelve phyla of other microbes accounting for 1.85% of the total relative abundance showed significantly higher abundance in the unplanted wetland. Planted wetlands shared more similar microbial community structure distinguished from that of the unplanted one. Additionally, distinct microbial interactive pattern could be observed in planted wetlands. Conclusions Based on their microbial compositions and interactive patterns, it will be reasonable to illustrate the higher wastewater purification ability of planted wetlands. Research here also supplies useful information for the potential of applicable combination of certain kinds of microbes for wastewater treatment.