Comparison of removal efficencies in mediterranean pilot constructed wetlands vegetated with different plant species

Constructedwetlands (CWs) arewastewater treatment systems suitable for reducing a contaminant loadin wastewater, economically. In this study, vegetated and unplanted pilot gravel filters, for tertiarytreatment of effluent froma conventional wastewater treatment plant (trickling filter) in Southern Italy(Sicily), are compared with pollutant removal efficiencies. Two beds are unplanted (control systems)whereas eight beds are planted with four differentmacrophyte species: Vetiveria zizanoides,Miscanthus xgiganteus, Arundo donax and Phragmites australis. The treatment performance of each wetland has beenevaluated using the load removal efficiency (LRE) in order to take into account the ET effect. Thecomparison betweenwetland treatment removal of vegetated H-SSF CWs and unplanted filters showedthat systems with plants have achieved a higher treatment efficiency. ET, measured in vegetated beds,appeared different from ET of control units, underlining the strong effect of vegetation.ã 2014 Elsevier B.V. All rights reserved.