|Title||Impact of the Fenton-like treatment on the microbial community of a diesel-contaminated soil|
|Publication Type||Journal Article|
|Year of Publication||2018|
|Authors||Polli F., Zingaretti D., Crognale S., Pesciaroli L., D'Annibale A., Petruccioli M., Baciocchi R.|
|Type of Article||Article|
|Keywords||Bioremediation, degradation, DGGE, Diesel contamination, Environmental Sciences & Ecology, Fenton, hydrocarbons, hydrogen-peroxide, petroleum, polluted soil, qPCR, remediation, respiration, SCALE, situ chemical oxidation|
Fenton-like treatment (FLT) is an ISCO technique relying on the iron-induced H2O2 activation in the presence of additives aimed at increasing the oxidant lifetime and maximizing iron solubility under natural soil pH conditions. The efficacy of FLT in the clean-up of hydrocarbon-contaminated soils is well established at the field-scale. However, a better assessment of the impact of the FLT on density, diversity and activity of the indigenous soil microbiota, might provide further insights into an optimal combination between FLT and in-situ bioremediation (ISB). The aim of this work was to assess the impacts of FLT on the microbial community of a diesel-contaminated soil collected nearby a gasoline station. Different FLT conditions were tested by varying either the H2O2 concentrations (2 and 6%) or the oxidant application mode (single or double dosage). The impact of these treatments on the indigenous microbial community was assessed immediately after the Fenton-like treatment and after 30, 60 and 90 d and compared with enhanced natural attenuation (ENA). After FLT, a dramatic decrease in bacterial density, diversity and functionality was evident. Although in microcosms with double dosing at 2% H2O2 a delayed recovery of the indigenous microbiota was observed as compared to those subjected to single oxidant dose, after 60 d incubation the respiration rate increased from 0.036 to 0.256 mu g C-CO2 g(-1). Irrespective of the oxidant dose, best degradation results after 90 d incubation (around 80%) were observed with combined FLT, relying on double oxidant addition, and bioremediation. (C) 2017 Elsevier Ltd. All rights reserved.