The aim of this study was to evaluate biomass production of “no-food” energy crops irrigated with low qualitywater at different ETc restitutions (0%, 50 and 100%). The research was carried out, in 2011 and 2012, in anopen field near the full-scale constructed wetland (CW) municipal treatment plant located in the Eastern Sicily(Italy). The CW effluent has been applied in a experimental irrigation field of Vetiveria zizanoides (L.) Nash,Miscanthus x giganteus Greef et Deu. and Arundo donax (L.). Physical, chemical and microbiological analyseswere carried out on wastewater samples collected at inlet and outlet of CW and pollutant removal efficiencieswere calculated for each parameter. Bio-agronomical analyses on herbaceous species were made with the goal toevaluate the main parameters such as the plant dimension, the growth response and the biomass production.Average TSS, COD and TN removal for CW were about 74%, 67% and 68%, respectively. Although thesatisfactory Escherichia coli removal, about 3.3 log unit for both beds on average, CW didn’t achieve therestrictive Italian law limits for wastewater reuse. As expected, irrigation was beneficial and the full ETreplenishment increased the biomass productivity as compared to the other two treatment. The mean productivityof Vetiveria and Myscanthus were respectively about 9, 26 and 38 t ha-1 and 3, 7 and 12 t ha-1 in 0%, 50% and100% ETc restitutions. Arundo gave higher values of dry biomass (79 t ha-1 in 100% ETc restitution in 2011season). These results highlight the potential in the use of constructed wetland effluents for the irrigation of highbiomass herbaceous production, particularly in semiarid regions such as the Mediterranean area, overcomingsome problems of the sustainability of energy crops.
|Titolo:||Wastewater reuse for irrigation of energy crops|
|Data di pubblicazione:||2014|
|Appare nelle tipologie:||4.1 Contributo in Atti di convegno|