Mohsen Samimi; Mohsen Shahriari Moghadam
Abstract
Background and Purpose: Phytoremediation stands out as one of the effective techniques for stabilizing, extracting, trapping, or detoxifying pollutants utilizing plants. This cost-effective and environmentally friendly approach leads to the revitalization and enhancement of vegetation, along with increased ...
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Background and Purpose: Phytoremediation stands out as one of the effective techniques for stabilizing, extracting, trapping, or detoxifying pollutants utilizing plants. This cost-effective and environmentally friendly approach leads to the revitalization and enhancement of vegetation, along with increased activity and growth of microorganisms. In this study, the species cultivated in the tailings of the lead and zinc mines of Ravanj were identified and assessed.Materials and Methods: Indigenous plants thriving in mineral tailings were isolated from the root portion. Random sampling of the identified soil and plant species was conducted. The accumulation of heavy metals (lead, zinc, manganese, chromium, copper, nickel, cadmium, and cobalt) in the soil, aerial organs, and roots of plants were quantified. Additionally, the bioconcentration factor of the aerial and root parts and the transfer factor were computed.Results: Among the heavy metals, cadmium, zinc, lead, and manganese displayed the highest accumulations in the leaves of Euphorbia macroclada (3.91±0.17 mg/kg), Verbascum speciosum (751.94±42.67 mg/kg), Acanthophyllum microcephalum (272.11±31.73 mg/kg), and Acanthophyllum microcephalum (594.59±9.76 mg/kg), respectively. Conversely, cobalt, chromium, copper, and nickel exhibited the most significant accumulations in the roots of Acantholimon hohenackeri (3.17±0.55 mg/kg), Acantholimon hohenakeri (20.16±2.28 mg/kg), Euphorbia macroclada (19.51±0.36 mg/kg), and Verbascum speciosum (17.56±0.90 mg/kg), respectively. Euphorbia macroclada demonstrated the highest bioconcentration in aerial parts and roots concerning cadmium metal (0.40). Furthermore, the Acantholimon hohenackeri plant exhibited the highest transfer factor (2.75), primarily associated with lead metal.Conclusion: Based on the findings of this study, the investigated species within the lead and zinc mines of Ravanj could serve as heavy metal-resistant ecotypes, contributing to the reduction of heavy metal mobility and bioavailability, thereby enhancing soil texture quality.
Somayeh Sefidgar Shahkolaie; Mojtaba Barani Motlaq; Farhad Khormali; Esmael Dordipour
Abstract
Background and purpose: Increasing agricultural activities and subsequently releasing pollutants from agricultural systems as well as expanding industries cause heavy metals (lead and cadmium) to enter the environment. Application of amendments are suitable methods for the inactivation of heavy metals ...
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Background and purpose: Increasing agricultural activities and subsequently releasing pollutants from agricultural systems as well as expanding industries cause heavy metals (lead and cadmium) to enter the environment. Application of amendments are suitable methods for the inactivation of heavy metals in contaminated soils. Materials and methods: In order to study the effect of organic amendments (bichar 640 and 420) and inorganic amendments (zeolite, bentonite, leca and pumice) on bioavailability of Pb and Cd during incubation time in a calcareous soil, a factorial experiment was conducted in a completely randomized design with 3 levels of amendments application in soil (0, 1 and 5 %) in three replications. Bioavailability of Pb and Cd in soil was determined using DTPA and EDTA- extractable during 90- and 180-days incubation time. Results: Results showed that concentration of DTPA-extractable Pb and Cd increased during the time. Application of biochar 640, bentonite and zeolite (5%) decreased concentration of EDTA-extractable Pb during the incubation time. Application of biochar (1%) were the most effective treatment in decreasing Pb concentration EDTA-exchangeable. Application of the organic amendments (biochar 640 and biochar 420) and inorganic amendments (pumice, leca bentonite, and zeolite) increased concentration of EDTA-extractable Cd during the incubation time. Application of 5% of zeolite showed the lowest increasing concentration of EDTA-extractable Cd during the incubation time. Conclusion: Organic amendments were more efficient in immobilization of Cd and Pb than the inorganic amendments. These results might due to the high amount of organic carbon and cation exchange capacity of the organic amendments than the inorganic amendments.