title: Bioremediation of diesel contamination at an underground storage tank site: a spatial analysis of the microbial community.
abstract: The present study reports on a real case of contamination due to the chronic leakage of diesel fuel from an underground tank at a dismissed service station. Speciation of the microbial community according to both lateral and vertical gradients from the origin of the contaminant release was analyzed by means of the PCR-DGGE technique. Moreover, the effects of a landfarming treatment on both the microbial community structure and the abatement of contamination were analyzed. The concentration of total petrol hydrocarbons (TPHs) decreased along the horizontal gradient (from 7042.2 ± 521.9 to 112.2 ± 24.3 mg kg(-1)), while increased downwards from the position of the tank (from 502.6 ± 43.7 to 4972.5 ± 275.3 mg kg(-1)). PCR-DGGE analyses and further statistical treatment of the data indicated a correlation between structure of the bacterial communities and amount of diesel fuel contamination. On the other hand, level of contamination, soil texture and depth were shown to affect the fungal community. Chloroflexi and Ascomycota were the most abundant microbes ascertained through culture-independent procedures. Landfarming promoted 91.6 % reduction of TPHs in 75 days. Furthermore, PCR-DGGE analyses evidenced that both bacterial and fungal communities of the treated soil were restored to the pristine conditions of uncontaminated topsoil. The present study demonstrated that bacterial and fungal communities were affected differently by soil factors such as level of hydrocarbon contamination as well as soil depth and texture. This report shows that a well-planned landfarming treatment can drive the restoration of the soil in terms of both abatement of the contaminants and resilience of the microbial community structure.
authors.affiliation: Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy. marco.andreolli@univr.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Andreolli
authors.affiliation: Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Albertarelli
authors.affiliation: Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Lampis
authors.affiliation: Eurovix SpA, Via E. Mattei, 17, 24060, Entratico, BG, Italy.
authors.forename: Pierlorenzo
authors.initials: P
authors.lastname: Brignoli
authors.affiliation: Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Nazaninalsadat Seyed
authors.initials: NS
authors.lastname: Khoei
authors.affiliation: Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134, Verona, Italy. giovanni.vallini@univr.it.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Vallini
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D001673:Biodegradation, Environmental; D044822:Biodiversity; D005658:Fungi / Q000235:genetics / Q000302:isolation & purification; D005742:Gasoline / Q000382:microbiology*; D006838:Hydrocarbons / Q000378:metabolism*; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D017423:Sequence Analysis, RNA; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
chemical_list: D005742:Gasoline; D006838:Hydrocarbons; D012336:RNA, Ribosomal, 16S; D012987:Soil; D012989:Soil Pollutants
keywords: Bioremediation; Diesel leakage; Hydrocarbons contaminated soil; Landfarming; PCR–DGGE; Underground tank