Remediation of a heavy metals contaminated soil using mycorrhized and non‐mycorrhized Helichrysum italicum (Roth) Don

摘要

Four hundred hectares of the inland and hilly part of Apulia Region (Southern Italy) were contaminated by using low‐quality composts for many years. That territory now belongs to a nationaludpark and needs a sustainable soil restoration. Therefore, a greenhouse experiment was carried out to test the phytoremediation potential of the frugal Helichrysum italicum (Roth) Don, aloneudand mycorrhized by Septoglomus viscosum. The aims of the research were (a) to test if the H. italicum can reduce the soil content of Cd, Co, Cr, Cu, Ni, Pb, and Zn; (b) to identify in whichudpart of the plant those metals are mainly accumulated; (c) to check the role of S. viscosum in promoting the plant growth and the soil phytoremediation. The results showed better plant growthudin contaminated soils in comparison to control soils, regardless of the presence of mycorrhiza, probably due to the better soil fertility parameters in contaminated soils. In addition, non‐udmycorrhized plants from contaminated soil accumulated greater amounts of heavy metals, especially Cr, Cu, Pb, and Zn, in their root system. According to the translocation and bioconcentrationudfactors, the mechanism by which H. italicum incorporated heavy metals was ascribable to a phytostabilization process. In contrast, the application of mycorrhiza in the contaminated soiludreduced the uptake of heavy metals by the roots, possibly through an exclusion mechanism, reducing the phytoremediation potential of H. italicum.