The Effects of Plants on Pollutant Removal, Clogging, and Bacterial Community Structure in Palm Mulch-Based Vertical Flow Constructed Wetlands

Abstract

In this study, the effects of plants on the performance and bacterial community structure of palm mulch-based vertical flow constructed wetlands was studied. The wetlands were built in August 2013; one of them was planted with Canna indica and Xanthosoma sp., and the other one was not planted and used as a control. The experimental period started in September 2014 and finished in June 2015. The influent was domestic wastewater, and the average hydraulic surface loading was 208 L/m2d, and those of COD, BOD, and TSS were 77, 57, and 19 g/m2d, respectively. Although the bed without plants initially performed better, the first symptoms of clogging appeared in December 2014, and then, its performance started to fail. Afterwards, the wetland with plants provided better removals. The terminal restriction fragment length polymorphism (T-RFLP) analysis of Enterococci and Escherichia coli in the effluents suggests that a reduction in their biodiversity was caused by the presence of the plants. Thus, it can be concluded that the plants helped achieve better removals, delay clogging, and reduce Enterococci and E. coli biodiversity in the effluents.

Efficient Wastewater Treatment and Removal of Bisphenol A and Diclofenac in Mesocosm Flow Constructed Wetlands Using Granulated Cork as Emerged Substrate

“…The results also showed significant differences ( p < 0.05) between systems in ammonium removal due to the macrophyte species. Carrasco-Acosta [ 70 ] and Kraiem [ 52 ] reported the multiple effects that macrophytes may have on nutrient removal as it improves the hydraulic conductivity, enhances the biofilm development, and then influences the microbial activity by transferring the oxygen from the atmosphere to the substrate and ensuring enhanced aeration of the bed. Otherwise, the roots can provide adhesion and oxygenation to microbes [ 71 ].…”

Development of Multiplex RT qPCR Assays for Simultaneous Detection and Quantification of Faecal Indicator Bacteria in Bathing Recreational Waters

“…Filters were individually homogenised in liquid nitrogen, and each one was individually placed in microtubes for the extraction of environmental DNA (eDNA). eDNA extraction was performed according to the CTAB method described in [ 49 ] and modified in [ 50 ].…”

Wetlands for environmental protection

“…Although BOD, COD, and TSS removal was satisfactory, clogging began to be seen within the first few years of operation leading to overland flow and deteriorated hydraulics within the system (Vasconcellos, Sperling, & Ocampos, 2019). Another study looked at the performance and bacterial structure of planted and nonplanted mulch-based VFCWs (Carrasco-Acosta et al, 2019). Although the nonplanted control had a higher removal efficiency at first, it began to fail once clogging was observed.…”

“…Vertical flow constructed wetlands planted with Canna indica and Xanthosoma spp. showed a better reduction of Enterococci and E. coli biodiversity than that of unplanted ones while treating rural household wastewater in community structure mulch‐based VFCWs (Carrasco‐Acosta, Garcia‐Jimenez, Herrera‐Melián, Peñate‐Castellano, & Rivero‐Rosales, 2019). More than 90% removal of antibiotic resistance bacteria and high removal rate of enterobacteria and enterococci bacteria (86%–100%) were obtained while treating wastewater in CWs planted with P. australis (Santos, Almeida, Ribeiro, Ferreira, et al, 2019; Santos, Almeida, Ribeiro, & Mucha, 2019).…”