title: Natural attenuation of residual heavy metal contamination in soils affected by the Aznalcóllar mine spill, SW Spain.
abstract: Non-amended soils affected by pyritic sludge residues were monitored for 7 years to assess the long-term natural attenuation ability of these soils. The decrease in both the total concentration of elements (particularly As) and (NH(4))(2)SO(4)-extractable fractions of Mn, and Zn, below the maximum permissible levels indicate a successful natural ability to attenuate soil pollution. Soil acidification by pyrite oxidation and rainfall-enhanced leaching were the largest contributors to the reduction of metals of high (Mn, Cu, Zn and Cd) and low (Fe, Al, and As) availability. Periodic use of correlation and spatial distribution analysis was useful in monitoring elemental dispersion and soil property/element relationships.
authors.affiliation: Department of Agricultural Chemistry, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
authors.forename: Saúl
authors.initials: S
authors.lastname: Vázquez
authors.forename: América
authors.initials: A
authors.lastname: Hevia
authors.forename: Eduardo
authors.initials: E
authors.lastname: Moreno
authors.forename: Elvira
authors.initials: E
authors.lastname: Esteban
authors.forename: Jesús M
authors.initials: JM
authors.lastname: Peñalosa
authors.forename: Ramón O
authors.initials: RO
authors.lastname: Carpena
mesh_terms: D004190:Disasters; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D006863:Hydrogen-Ion Concentration; D019216:Metals, Heavy / Q000032:analysis*; D008906:Mining; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain; D013050:Spectrometry, Fluorescence; D013054:Spectrophotometry, Atomic; D013997:Time Factors
chemical_list: D019216:Metals, Heavy; D012989:Soil Pollutants