Heavy metal partitioning in river sediments severely polluted by acid mine drainage in the Iberian Pyrite Belt |
| |
| Institution: | 1. Departamento de Cristalograf??a y Mineralog??a, Facultad de Qu??mica, Universidad de Sevilla, 41071-, Sevilla, Spain;2. Departamento de Qu??mica y Ciencia de los Materiales, Escuela Politécnica Superior, Universidad de Huelva, 21819- Palos de la Frontera, Huelva, Spain;3. Departamento de Geolog??a, Facultad de Ciencias Experimentales, Universidad de Huelva, 21819-Palos de la Frontera, Huelva, Spain;1. Department of Economics, University of Wisconsin, Madison, WI 53706, United States;2. Department of Economics, Northwestern University, Evanston IL 60208, United States;1. Department of Earth Sciences & Research Center on Natural Resources, Health and the Environment (Natur HE), University of Huelva, Campus ‘El Carmen’, 21071, Huelva, Spain;2. Department of Earth and Planetary Science, University of California Berkeley, McCone Hall, CA, 94720-4767, Berkeley, USA;3. Department of Mining Engineering, University of Chile, Av. Tupper 2069, 8370451, Santiago, Chile;4. École Polytechnique Fédérale de Lausanne, Environmental Microbiology Laboratory (EML), Station 6, CH-1015, Lausanne, Switzerland;5. Elettra-Sincrotrone Trieste, s.s. 14 km 165.3, 34149, Basovizza, Trieste, Italy;1. Instituto Andaluz de Ciencias de La Tierra, CSIC & UGR, Avenida de Las Palmeras 4, 18100, Armilla, Granada, Spain;2. Department of Earth Sciences & Research Center on Natural Resources, Health and the Environment, University of Huelva, Campus ‘El Carmen’, E-21071, Huelva, Spain;3. Institut de Planétologie et D’Astrophysique de Grenoble, CNRS, Université Grenoble Alpes, F-38000, Grenoble, France;4. Department of Mineralogy and Petrology, UGR, Avda. Fuentenueva s/n, E-18002, Granada, Spain;5. University Grenoble Alpes, CNRS, IRD, IFSTTAR, ISTerre, 38000, Grenoble, France;1. School of Civil and Environmental Engineering, University of the Witwatersrand, Private Bag 3, Wits 2050, South Africa;2. Council for Scientific and Industrial Research (CSIR), Built Environment (BE), Hydraulic Infrastructure Engineering (HIE), P.O. Box 395, Pretoria, 0001, South Africa;3. Department of Environmental Sciences, School of Agriculture and Environmental Sciences, University of South Africa (UNISA), P. O. Box 392, Florida, 1710, South Africa;4. ROC Water Technologies, South Africa |
| |
| Abstract: | This study provides a geochemical partitioning pattern of Fe, Mn and potentially toxic trace elements (As, Cd, Cr, Cu, Ni, Pb, Zn) in sediments historically contaminated with acid mine drainage, as determined by using a 4-step sequential extraction scheme. At the upperstream, the sediments occur as ochreous precipitates consisting of amorphous or poorly crystalline oxy-hydroxides of Fe, and locally jarosite, whereas the estuarine sediments are composed mainly of detrital quartz, illite, kaolinite, feldspars, carbonates and heavy minerals, with minor authigenic phases (gypsum, vivianite, halite, pyrite). The sediments are severely contaminated with As, Cd, Cu, Pb and Zn, especially in the vicinity of the mining pollution sources and some sites of the estuary, where the metal concentrations are several orders of magnitude above background levels. Although a significant proportion of Zn, Cd and Cu is present in a readily soluble form, the majority of heavy metals are bonded to reducible phases, suggesting that Fe oxy-hydroxides have a dominant role in the metal accumulation. In the estuary, the sediments are potentially less reactive than in the riverine environment, because relevant concentrations of heavy metals are immobilised in the crystalline structure of minerals. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
