The purpose of this study was to assess the medium-term impact (2000-07) of drip irrigation with treated wastewater on total and bioavailable (DTPA-extractable) contents of Cd, Ni, Pb, Cu, and Zn in a sandy loam soil of a mature olive orchard in Southern Italy. Heavy metals analyses were performed on wastewater and topsoil samples (0-30 cm) collected from the areas wetted by the drippers and from a reference soil (rainfed plot). Annual irrigation volume distributed per hectare was 3068 m3. The amount of total heavy metals applied by irrigation over the 8-year experimental period was of 43, 110, 200, 680, and 2263 g ha-1 for Cd, Ni, Pb, Cu, and Zn, respectively, and well below the quantity of metals which can be distributed yearly by sewage sludge according to the pertinent Italian law. Wastewater application increased soil concentration of both total heavy metals and their bioavailable fraction even if at not critical values. Therefore, a systematic monitoring of soil metal concentration (as total and available forms) is recommended every 4-5 years in order to evaluate the risk due to the reuse of urban treated wastewater especially in shallow soils.
Distribuzione di metalli pesanti in un suolo di un oliveto microirrigato con acque reflue urbane trattate
PALESE, Assunta Maria;CELANO, Giuseppe;XILOYANNIS, Cristos
2013-01-01
Abstract
The purpose of this study was to assess the medium-term impact (2000-07) of drip irrigation with treated wastewater on total and bioavailable (DTPA-extractable) contents of Cd, Ni, Pb, Cu, and Zn in a sandy loam soil of a mature olive orchard in Southern Italy. Heavy metals analyses were performed on wastewater and topsoil samples (0-30 cm) collected from the areas wetted by the drippers and from a reference soil (rainfed plot). Annual irrigation volume distributed per hectare was 3068 m3. The amount of total heavy metals applied by irrigation over the 8-year experimental period was of 43, 110, 200, 680, and 2263 g ha-1 for Cd, Ni, Pb, Cu, and Zn, respectively, and well below the quantity of metals which can be distributed yearly by sewage sludge according to the pertinent Italian law. Wastewater application increased soil concentration of both total heavy metals and their bioavailable fraction even if at not critical values. Therefore, a systematic monitoring of soil metal concentration (as total and available forms) is recommended every 4-5 years in order to evaluate the risk due to the reuse of urban treated wastewater especially in shallow soils.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
