Research focusing on plant performance in constructed wetlands and agronomic application of treated wastewater - A set of experimental studies in Sicily (Italy)

• Published in: PloS one 2019-07, Vol.14 (7), p.e0219445-e0219445
• Main Authors: Licata, Mario, Gennaro, Maria Cristina, Tuttolomondo, Teresa, Leto, Claudio, La Bella, Salvatore
• Format: Article
• Language: English
• Subjects: Agricultural management; Agricultural systems; Agricultural wastes; Agriculture; Agrochemicals; Agronomy; Aquatic plants; Artificial wetlands; Biology and Life Sciences; Biomass; Biomass energy; Chemical pollution; Clean technology; Climate; Consortia; Constructed wetlands; Contaminants; Crops; Cyperus; Earth Sciences; Ecology and Environmental Sciences; Efficiency; Environmental aspects; Farming systems; Fertilizers; Flow system; Flowers & plants; Food; Green technology; Horticultural crops; Irrigation; Macrophytes; Methods; Microbiology; Monoculture; Organic chemistry; Organic compounds; Physical Sciences; Physiological adaptation; Plant growth; Plant species; Plants; Pollutant removal; Pollutants; Polyculture; Production processes; Renewable energy; Sewage treatment; Sicily; Storm seepage; Subsurface flow; Sustainability; Sustainable agriculture; Sustainable development; Technology; Waste Water - analysis; Waste Water - chemistry; Wastewater; Wastewater irrigation; Wastewater pollution; Wastewater reuse; Wastewater treatment; Water Pollutants, Chemical - analysis; Water Pollutants, Chemical - chemistry; Water Purification; Water reuse; Wetlands
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0219445

Constructed wetlands are sustainable technologies for the treatment of wastewater. These biological systems have been widely studied throughout the world for more than 30 years; however, most studies have focused on the effects of design and engineering on pollutant removal from wastewater. Undoubtedly, agro-technical aspects have been given too little consideration by research. This paper reports the main results of a set of experiments carried out on two pilot horizontal subsurface flow systems in Sicily (Italy). Festuca, Lolium and Pennisetum spp. in combination and three emergent macrophytes-Arundo donax L., Cyperus alternifolius L. and Typha latifolia L.-alone, were assessed. The aim of the study was to demonstrate that, under predetermined hydraulic and design conditions, the choice of plant species and the management of the vegetation can significantly affect the pollutant removal performance of constructed wetlands. In addition, wastewater (after treatment) can also be used for agricultural purposes leading to increased sustainability in agricultural systems. Arundo and Typha-planted units performed better than Cyperus-planted units in terms of chemical, physical and microbiological contaminant removal. All the species adapted extremely well to wetland conditions. Polyculture systems were found to be more efficient than monocultures in the removal of dissolved organic compounds. The reuse of treated wastewater for the irrigation of open fields and horticultural crops led to significant savings in the use of freshwater and fertilizers. The results of physical-energy characterization of A. donax above-ground plant residues and pellets highlighted the fact that a constructed wetland could also be a potential source of bioenergy.