Alleviation of environmental risks associated with severely contaminated mine tailings using amendments: Modeling of trace element speciation, solubility, and plant accumulation. (28th June 2016)

• Record Type: Journal Article
• Authors: Pardo, Tania; Bes, Cleménce; Bernal, Maria Pilar; Clemente, Rafael
• Is Part Of: Environmental toxicology and chemistry. Volume 35:Number 11(2016:Nov.)
• Page Start: 2874
• Page End: 2884
• Publication Date: 2016-06-28
• Subjects: Soil contamination -- Metal speciation -- Metal accumulation -- Solubilization mechanisms -- Phytostabilization; Pollution -- Environmental aspects -- Periodicals; Environmental chemistry -- Periodicals; 615.902
• DOI: 10.1002/etc.3434
• Languages: English
• ISSNs: 0730-7268

Abstract

Abstract: Tailings are considered one of the most relevant sources of contamination associated with mining activities. Phytostabilization of mine spoils may need the application of the adequate combination of amendments to facilitate plant establishment and reduce their environmental impact. Two pot experiments were set up to assess the capability of 2 inorganic materials (calcium carbonate and a red mud derivate, ViroBind TM ), alone or in combination with organic amendments, for the stabilization of highly acidic trace element–contaminated mine tailings using Atriplex halimus . The effects of the treatments on tailings and porewater physico‐chemical properties and trace‐element accumulation by the plants, as well as the processes governing trace elements speciation and solubility in soil solution and their bioavailability were modeled. The application of the amendments increased tailings pH and decreased (>99%) trace elements solubility in porewater, but also changed the speciation of soluble Cd, Cu, and Pb. All the treatments made A. halimus growth in the tailings possible; organic amendments increased plant biomass and nutritional status, and reduced trace‐element accumulation in the plants. Tailings amendments modified trace‐element speciation in porewater (favoring the formation of chlorides and/or organo‐metallic forms) and their solubility and plant uptake, which were found to be mainly governed by tailing/porewater pH, electrical conductivity, and organic carbon content, as well as soluble/available trace‐element concentrations. Environ Toxicol Chem 2016;35:2874–2884. © 2016 SETAC