Comparative bioremediation of heavy metals and petroleum hydrocarbons co-contaminated soil by natural attenuation, phytoremediation, bioaugmentation and bioaugmentation-assisted phytoremediation.
Sci Total Environ
; 563-564: 693-703, 2016 Sep 01.
Article
em En
| MEDLINE
| ID: mdl-26524994
ABSTRACT
Biological remediation technologies are an environmentally friendly approach for the treatment of polluted soils. This study evaluated through a pot experiment four bioremediation strategies a) natural attenuation, b) phytoremediation with alfalfa (Medicago sativa L.), c) bioaugmentation with Pseudomonas aeruginosa and d) bioaugmentation-assisted phytoremediation, for the treatment of a co-contaminated soil presenting moderate levels of heavy metals (Cu, Pb and Zn at 87, 100 and 110mgkg(-1) DW, respectively) and petroleum hydrocarbons (3800mgkg(-1) DW). As demonstrated by plant biomass and selected physiological parameters alfalfa plants were able to tolerate and grow in the co-contaminated soil, especially when soil was inoculated with P. aeruginosa, which promoted plant growth (56% and 105% increase for shoots and roots, respectively) and appeared to alleviate plant stress. The content of heavy metals in alfalfa plants was limited and followed the order Zn>Cu>Pb. Heavy metals were mainly concentrated in plant roots and were poorly translocated, favouring their stabilization in the root zone. Bioaugmentation of planted soil with P. aeruginosa generally led to a decrease of plant metal concentration and translocation. The highest degree of total petroleum hydrocarbon removal was obtained for bioaugmentation-assisted phytoremediation treatment (68%), followed by bioaugmentation (59%), phytoremediation (47%) and natural attenuation (37%). The results of this study demonstrated that the combined use of plant and bacteria was the most advantageous option for the treatment of the present co-contaminated soil, as compared to natural attenuation, bioaugmentation or phytoremediation applied alone.
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MEDLINE
Assunto principal:
Pseudomonas aeruginosa
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Poluentes do Solo
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Poluição por Petróleo
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Metais Pesados
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Medicago sativa
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Recuperação e Remediação Ambiental
Idioma:
En
Ano de publicação:
2016
Tipo de documento:
Article