Abstract
Although polycyclic aromatic hydrocarbons (PAHs) are environmental pollutants that affect negatively soils biology, several strategies lead to their removal such as the phytoremediation. In order to assess the potential of phytoremediation using "alfalfa" Medicago sativa as a strategy to reduce the phenanthrene on the soil, we analyzed the structure and dynamic of the microbial communities of a microcosm soil artificially contaminated with phenanthrene (2000ppm), which was exposed to the plants. At different incubation times (7, 14, 21, 28, 42, and 56days), a soil sample was taken from each microcosm and the residual amount of phenanthrene was quantified. Dehydrogenase activity and the count of fungi and bacteria were also estimated. Bacterial communities were characterized using PCR-DGGE, Shannon and Weaver's indexes, multivariate analysis, and rarefaction curves. It was found that phytoremediation treatment was associated with a higher richness and bacterial diversity compared with those on control soil. Although an OTUs (Operational Taxonomic Unit) succession over time was detected in both treatments, bacterial richness and diversity were conditioned by the phenanthrene concentration available and also dependent on the treatment, which were associated to different bacterial communities. In this study, phytoremediation treatment reduced the content of phenanthrene in the soil after 56days to a 0.45% compared with the control treatment, which only reached to 4.25%. This preliminary work suggests the promoting activity of "alfalfa" plants, through rhizodegradation, to remove in soil PAHs, as well as its relevance in the activation of different ecological processes mediated by soil microorganisms.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.