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

Abstract

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 national park 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, alone and 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 which part 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 growth in 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, nonmycorrhized 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 bioconcentration factors, the mechanism by which H. italicum incorporated heavy metals was ascribable to a phytostabilization process. In contrast, the application of mycorrhiza in the contaminated soil reduced the uptake of heavy metals by the roots, possibly through an exclusion mechanism, reducing the phytoremediation potential of H. italicum. KEYWORDSheavy metals bioconcentration, heavy metals translocation, mycorrhizal fungus, phytostabilization, soil metals contaminationLand degradation includes many processes affecting natural resources (including soil), which reduce their capacity to carry out their ecological functions and, therefore, cause degradation (Sacristán, Peñarroya, & Recatalá, 2015). Among these processes, the heavy metals contamination has assumed considerable relevance in recent decades because of the increasing human activities that release these inorganic pollutants.In fact, they impact negatively on the soil microbial community due to their toxicity (Khan, Hesham, Qiao, Rehman, & He, 2010) and, especially Hg, Cd, Pb, As, Cu, Zn, Sn, and Cr, can accumulate in the tissues of living organisms (Wright, 2007). of Pb in roots (Cao, Cappai, Carucci, & Muntoni, 2004). It grows in dry places, well exposed to sun, and often in sandy and in uncultivated soils, and it is able to colonize rocky and marginal areas, contributing with its root system to the consolidation of soils. This frugal plant can be used Each site was sampled using a hand auger, collecting several soil subsamples from the top 20 cm and following an X scheme in an area of about 100 m 2 . The weight of each composite sample was about 150 kg, and an aliquot was air dried, crushed, and passed through a 2-mm sieve. | Greenhouse experiments

Ex situ phytoremediation trial of Sardinian mine waste using a pioneer plant species

“…Similar behavior was observed also on other species of the genus Helichrysum , like H. italicum (Roth) G.Don subsp. italicum (Brunetti et al 2017 ).…”

“…viscosa (Lai et al 2015;Jiménez et al 2021) showed TF higher than H. tyrrhenicum. Otherwise, in the study of Brunetti et al (2017), H. italicum subsp. italicum have shown the capability to accumulate metals mainly into roots.…”

Biofuel Production Using Thermochemical Conversion of Heavy Metal-Contaminated Biomass (HMCB) Harvested from Phytoextraction Process

“…As can be seen in Table 1, Brunetti et al [127] have conducted a comparative study between the phytoremediation potential of frugal Helichrysum italicum and mycorrhized Helichrysum italicum by Septoglomus viscosum applied for remediation of a land contaminated by Cd, Cu, Zn, Pb, Cr, Ni, and Co, over a twelve-month period. Results showed that the non-mycorrhized plant, i.e.…”

“…Helichrysum italicum accumulated greater amounts of HMs, especially Cr, Cu, Pb, and Zn, in their root system. On the other hand, Septoglomus viscosum used in the mycorrhized H. italicum study resulted in a better growth of plant in contaminated soils −likely because of the better soil fertility parameters in the brownfields−, however, its use decreased the uptake of HMs by the roots, which was possibly resulted from an exclusion mechanism, thereby reducing the phytoremediation capability of H. italicum and less extraction of the HMs from the contaminated soil (see Table 1) [127]. Kocoń and Jurga [111] studied a three-year micro-plot experiment to investigate the growth possibility and phytoextraction potential of two energy crops, i.e.…”

Two hyperspectral indices for detecting cadmium and lead contamination from arice canopy spectrum

“…We did not, however, explore the contaminative mechanism, which will be investigated in our future research. In particular, HMs are likely to react to co-contaminations with other hazardous material in soil, like polycyclic aromatic hydrocarbon (PAH) (Brunetti et al, 2018;Deary, Ekumankama, & Cummings, 2018;Wang et al, 2019). In our future research, we will study whether the proposed indices are still effective when the rice is subject to co-contaminations of Cd-Pb and PAH, and investigate how HMs harm tissues and affect photosynthesis in cell scale with hyperspectral remote sensing.…”