Abstract
The ability of four wetland vegetation: Typha latifolia, Cyperus papyrus, Cyperus alternifolius and Phragmites mauritianus in removing pathogenic and indicator microorganisms in the wetlands were studied in bucket experiments. The findings suggested that vegetated systems can effectively reduce faecal pathogens in wastewater. Both Salmonella species and Escherichia coli removal efficiencies were above 98%. This proved the positive use of plants in bacteria removal from wastewater. Nevertheless, removal of faecal bacteria differed significantly between macrophytes where C. alternifolius and T. latifolia were the most effective followed by C. papyrus and the least was P. mauritianus. The study also observed no significant difference between planted and unplanted buckets. The effect of physicochemical parameters such as dissolved oxygen, pH, temperature and salinity were thought to influence the bacterial removal. Key words: Constructed wetland, Typha latifolia, Cyperus papyrus, Cyperus alternifolius, Phragmites mauritianus, Salmonella species, Escherichia coli.
Highlights
Macrophytes play an important role in maintaining the wetland ecosystem
Removal of faecal bacteria differed significantly between macrophytes where C. alternifolius and T. latifolia were the most effective followed by C. papyrus and the least was P. mauritianus
The highest temperature was observed in P. mauritianus (25.0± 0.2°C) and the lowest was in C. alternifolius (24.4± 0.18°C)
Summary
Macrophytes play an important role in maintaining the wetland ecosystem. They have the capacity to improve water quality by removing faecal pathogens present-in with wastewater. The influence is principally explained by supply of oxygen to the roots, which plays a crucial role in the activity and type of metabolism performed by microorganisms in the root zone (Stottmeister et al, 2003), especially the grazing predators like protozoan, nematodes and zooplankton and lytic bacteria and viruses (Vymazal, 2005). Another potential source of removal is the adsorption by bio-films on the rock media and plant roots (Stevik et al, 2004; Stott and Tanner, 2005). Other mechanisms reducing microbial contaminants in vegetated systems are natural
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
