Surface geochemistry of soils associated to the Tinto River (Huelva, Spain).
The Tinto River (Iberian Pyritic Belt) is a unique ecosystem characterized by extreme acidity and abnormally high concentrations of heavy metals in water, sediments and alluvium, with high microbial diversity and low plant diversity. The low pH value, a direct consequence of the high amount of Fe and S derived from the bedrock, promotes the dispersion of heavy metals. Less mobile elements (Fe, As, Pb, Ag and Ti) show the highest concentrations in the mid stretches of the river while easily mobile metals (Cu, Zn and Cd) accumulate in the estuarine sediments. Tinto River soils show a scarcity of nutrients (Ca, K, P, Mg and Na) due to the lack of lithologic sources and to loss by acid washing. Sea water and phospho-gypsum deposits near Huelva contribute to increase the Na, Mg and P concentrations in the estuarine soils. As a whole these features represent an extreme habitat to which plants must adapt.
Rufo
Lourdes
L
Dpto. Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, E-28049 Madrid. lrufo@cbm.uam.es
Rodríguez
Nuria
N
Amils
Ricardo
R
de la Fuente
Vicenta
V
Jiménez-Ballesta
Raimundo
R
D004553:Electric Conductivity; D004784:Environmental Monitoring; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000032:analysis*; D008906:Mining; D045483:Rivers; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain
D008670:Metals; D012989:Soil Pollutants