Reuse of constructed wetland effluents for irrigation of energy crops.
The aim of this study was to evaluate biomass production of promising 'no-food' energy crops, Vetiveria zizanoides (L.) Nash, Miscanthus × giganteus Greef et Deu. and Arundo donax (L.), irrigated with low quality water at different evapotranspiration restitutions. Two horizontal subsurface flow (H-SSF) constructed wetland (CW) beds, with different operation life (12 and 6 years), were used to treat secondary municipal wastewaters for crop irrigation. Water chemical, physical and microbiological parameters as well as plant bio-agronomic characters were evaluated. The results confirm the high reliability of CWs for tertiary wastewater treatment given that the H-SSF1 treatment capacity remained largely unchanged after 12 years of operation. Average total suspended solids, chemical oxygen demand and total nitrogen removal for CWs were about 68, 58 and 71%, respectively. The Escherichia coli removal was satisfactory, about 3.3 log unit for both CW beds on average, but caution should be taken as this parameter did not achieve the restrictive Italian law limits for wastewater reuse. The average above-ground dry matter productions were 7 t ha⁻¹ for Vetiveria zizanoides, 24 t ha⁻¹ for Miscanthus × giganteus and 50 t ha⁻¹ for Arundo donax. These results highlight attractive biomass yield by using treated wastewater for irrigation with a complete restitution of evapotranspiration losses.
Department of Agri-food and Environmental Systems Management, University of Catania, Via Santa Sofia 100, Catania 95123, Italy and CSEI Catania, Via Santa Sofia 100, Catania 95123, Italy E-mail: giuseppe.cirelli@unict.it.
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Barbagallo
Department of Food and Agricultural Production Sciences, University of Catania, Via Valdisavoia 5, 95123 Catania, Italy.
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Barbera
Department of Agri-food and Environmental Systems Management, University of Catania, Via Santa Sofia 100, Catania 95123, Italy and CSEI Catania, Via Santa Sofia 100, Catania 95123, Italy E-mail: giuseppe.cirelli@unict.it.
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Cirelli
Department of Agri-food and Environmental Systems Management, University of Catania, Via Santa Sofia 100, Catania 95123, Italy and CSEI Catania, Via Santa Sofia 100, Catania 95123, Italy E-mail: giuseppe.cirelli@unict.it.
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Milani
Department of Agri-food and Environmental Systems Management, University of Catania, Via Santa Sofia 100, Catania 95123, Italy and CSEI Catania, Via Santa Sofia 100, Catania 95123, Italy E-mail: giuseppe.cirelli@unict.it.
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Toscano
D000383:Agriculture / Q000379:methods*; D057919:Biological Oxygen Demand Analysis; D018533:Biomass; D018556:Crops, Agricultural / Q000254:growth & development; D007558:Italy; D009584:Nitrogen / Q000378:metabolism; D006109:Poaceae / Q000254:growth & development; D015203:Reproducibility of Results; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
D014874:Water Pollutants, Chemical; D009584:Nitrogen