Influence of Phragmites communis and Zizania aquatica on rhizosphere soil enzyme activity and bacterial community structure in a surface flow constructed wetland treating secondary domestic effluent in China

Abstract

The present study aims to investigate the effects of Phragmites communis and Zizania aquatica on rhizosphere soil enzyme activity and bacterial community structure in a surface flow constructed wetland (SFCW) for the treatment of domestic sewage from the Shanxi province of China. The basic physical and chemical properties of the soil, the contents of soil urease (UE), alkaline phosphatase (ALP), soil microbial biomass carbon and nitrogen (SMBC, SMBN), and bacterial community structure were measured in the Phragmites communis group (PG), Zizania aquatica group (ZG), and control group (CG), respectively. The results showed that (1) the contents of UE, ALP, SMBC, and SMBN in rhizosphere soil of PG were more than those of ZG; (2) the highest bacterial abundance and αdiversity appeared in PG, in which Gp6 was the most abundant bacterial genus in PG; (3) the main functions of the dominant bacteria Gp6 and Longilinea in PG were involved in metabolizing multiple carbohydrates and participating in the carbon cycle in the soil based on the clusters of orthologous groups pathway analysis data; (4) the bacterial community of PG was mainly affected by the positive correlation with arsenic, nickel, or SMBC via the redundancy analysis. Collectively, Phragmites communis is a recommended species for wastewater wetland treatment system in Shanxi province, and the special enzymes and dominant bacteria in plant rhizosphere soil had obvious functions of removing organic pollutants. Besides, the influences of environmental factors on rhizosphere bacteria and the combined effects of Phragmites communis and dominant bacteria in wetland wastewater treatment system should be taken seriously.

Genomic insights on fighting bacterial wilt by a novel Bacillus amyloliquefaciens strain Cas02

“…Soil physical and chemical analyses indicated that application of strain Cas02 can alter the physical and chemical properties of rhizosphere soil. Soil enzymes are mainly derived from rhizosphere microbes and are the most active part of the soil organic components (Zhao et al ., 2020 ). As an important indicator for the conversion of soil nutrients, soil enzyme activity can reflect the circulation and health of soil nutrients (Baćmaga et al ., 2021 ).…”

Demonstration study of bypass multipond wetland system to enhance river water quality

“…The surface flow artificial wetlands also reoxygenated the water, mainly due to the disturbance caused by the flow of the water, surface disturbance of the water, etc. In addition, the growth and maturation of aquatic plants results in not only the absorption of harmful substances in sewage, but also provides oxygen to the water (Zhao et al 2020). When the oxygen produced by plant photosynthesis is delivered to the root zone in excess of the plant's needs, it diffuses outward from the root surface, allowing some recovery of DO in the water column.…”

A Review on Microorganisms in Constructed Wetlands for Typical Pollutant Removal: Species, Function, and Diversity

“…They have been widely used since the 1960s because of their simple operation, ease of maintenance, low cost, and environmental friendliness, providing a viable alternative to traditional wastewater treatment technologies ( Zhao et al, 2016 ; Zheng et al, 2021a , b ). They are mainly composed of substrate, plants, and microorganisms that purifying wastewater through the interaction of physical, chemical, and biological processes ( Zhao et al, 2020c ). Previous studies have shown that CWs can remove most environmental pollutants, including COD, N, P ( Lin et al, 2002 ; Li et al, 2013 ; Zhao et al, 2019 ), heavy metals ( Zhang et al, 2021e ), and antibiotics ( Liu et al, 2019 ), as well as some increasingly emerging pollutants (e.g., pesticides, flame retardants and persistent organic pollutants; Rajan et al, 2019 ; Long et al, 2021 ; Vymazal et al, 2021 ).…”

“…Previous studies have shown that CWs can remove most environmental pollutants, including COD, N, P ( Lin et al, 2002 ; Li et al, 2013 ; Zhao et al, 2019 ), heavy metals ( Zhang et al, 2021e ), and antibiotics ( Liu et al, 2019 ), as well as some increasingly emerging pollutants (e.g., pesticides, flame retardants and persistent organic pollutants; Rajan et al, 2019 ; Long et al, 2021 ; Vymazal et al, 2021 ). Consequently, CWs are widely used in the treatment of domestic sewage, industrial wastewater, mine drainage, land leachate, polluted lake water, effluent from the livestock industry and other wastewater ( Lin et al, 2002 ; Zhao et al, 2020c ).…”

“…The advent of methods such as 16S sequencing, metagenomics sequencing, and high-throughput sequencing technologies has not only allowed a more accurate assessment of microbial diversity but only the analysis of the relative abundances of different microbial species and of the overall community structure ( Zhao et al, 2016 ; Sanchez, 2017 ). In CWs, the diversity of microbial communities and the richness of certain species are key factors for efficient wastewater treatment ( Zhao et al, 2020c ). Therefore, in addition to the need for a summary of functional microorganisms, there is also a great need to study and analyze the effects of different pollutants on microbial diversity.…”