Abstract
Cyanobacterial blooms often occur in aquaculture wastewater in China. A floating plant, water hyacinth has been widely used to treat this wastewater. Little is known, however, about bacterial community characteristics and the risk of potential pathogens in cyanobacteria-blooming aquaculture wastewater remediated by water hyacinth. In wastewater treated with water hyacinth, we used culture enumeration and high-throughput sequencing to explore the characteristics of bacterial communities, the status of coliform bacteria, and pathogenic bacteria potentially conducive to human disease. Our results indicated that the relative abundance of Acidobacteria, Planctomycetes, Actinobacteria, Chlorobi, Cyanobacteria, Proteobacteria, and phylum OD1 in cyanobacteria-blooming aquaculture wastewater were significantly influenced by water hyacinth. After 30 days, the relative abundance of Proteobacteria and phylum OD1 in the water hyacinth treatments increased remarkably, while the relative abundance of the other 5 phyla in treatment was significantly reduced compared with the controls. In 21 major families, the relative abundance of Comamonadaceae, Oxalobacteraceae, Rhodocylclaceae, and an unnamed group from phylum OD1 increased significantly in the water hyacinth treatments compared with the controls. The number of total coliforms in wastewater treated by water hyacinth was significantly elevated and higher than controls during the first 6–18 days, with the maximum reaching 23,800 MPN/L. The level of potential pathogenic bacteria in wastewater treated by water hyacinth significantly reduced compared with the controls after 18 days, but it significantly increased from the initial level. It appears that water hyacinth by itself is not an effective treatment for reducing potential pathogens in aquaculture water.
Highlights
With the development of large-scale and high-density aquaculture industry in China, aquaculture wastewater of nearly 300 million cubic meters discharges into natural waterbodies every year [1].The large amount of residual feed and feces make the aquaculture water eutrophic
There was a significant difference in the relative abundance of Acidobacteria, Planctomycetes, Actinobacteria, Chlorobi, Cyanobacteria, Proteobacteria, and phylum OD1 between the controls and treatments over time (Figure 1)
The Chinese aquaculture wastewater is mostly accompanied by cyanobacterial bloom [21]
Summary
With the development of large-scale and high-density aquaculture industry in China, aquaculture wastewater of nearly 300 million cubic meters discharges into natural waterbodies every year [1]. A floating aquatic plant, has been widely used in China because of its superior ability to remove nitrogen and phosphorus [2]. Most studies on the influence of floating plants have focused on the reduction of nitrogen, phosphorus, and chemical oxygen demand in eutrophic water [3,4]. There is little information regarding the overall structure of bacterial communities and the status of potential pathogens in aquaculture wastewater after purification by floating plants. It is necessary to pay attention to the characteristics of bacterial communities and the situation of potential pathogens in M. aeruginosa-blooming aquaculture wastewater remediated by water hyacinth. We applied culture enumeration and high-throughput sequencing to quantify the changes in the characteristics of bacterial communities, specific bacteria including coliform bacteria, and pathogenic bacteria potentially conducive to human disease by treating cyanobacteria-blooming aquaculture wastewater with water hyacinth
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.