title: Spatial variations of heavy metals contamination in sediments from Odiel river (Southwest Spain).
abstract: The presence of heavy metal concentrations was examined in surface sediments from 27 sites within the Odiel river in the southwest Spain suffering inputs from industrial and mining activities. The interest is specially focused on the final delta located in the Odiel Natural Park, which constitutes a feeding ground of international importance for migrating birds. The behavior of 10 heavy metals (Zn, Cd, Pb, Cu, Cr, Mn, Ni, Fe, Hg) is conditioned by chemical properties of sediments such as acidity and carbonate or the presence of sulfate Very acidic sediments in the medium course of river contribute to the lower presence of metal as a consequence of leaching process. However, tidal action raises the pH in the marshes of the delta with correlative metal accumulation. In accordance with the Müller [Umschan 79 (1979) 133-149] scale for geoaccumulation index, the entire watercourse could be considered polluted by Zn and Pb, while Cu exhibits a high presence in the delta marshes of the river.
authors.affiliation: Departamento de Química y Ciencias de los Materiales, Escuela Politécnica Superior, Universidad de Huelva, Campus de la Rábida, 21819 Palos de la Frontera, Huelva, Spain.
authors.forename: J C
authors.initials: JC
authors.lastname: Santos Bermejo
authors.forename: R
authors.initials: R
authors.lastname: Beltrán
authors.forename: J L
authors.initials: JL
authors.lastname: Gómez Ariza
mesh_terms: D000818:Animals; D001717:Birds; D004032:Diet; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis*; D018570:Risk Assessment; D013030:Spain; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D019216:Metals, Heavy; D014873:Water Pollutants