Distribution of trace and rare earth elements in the estuary of Ría de Huelva (SW Spain): Field data and geochemical modeling

• Autores: Gutiérrez León, Joan; Millán Becerro, Ricardo; Carrero, Sergio; Pérez López, Rafael; Ceballos, Elina Estefania; Freydier, Rémi; Soler, Josep M.; Cama, Jordi
• Año de publicación: 2024
• Idioma: inglés
• Tipo de recurso: artículo
• Materia: METALS; ADSORTION MODELING; GEOCHEMICAL DISTRIBUTION; ESTUARY
• Institución: Consejo Nacional de Investigaciones Científicas y Técnicas

The geochemistry of the Ría de Huelva estuary (Spain) has been widely studied owing to its unique conditions due to mixing of acid mine drainage (AMD), river water and seawater, which have been aggravated by the existence of an adjacent phosphate fertilizer plant and its associated phosphogypsum stack.To better understand the complex geochemistry of the overall estuarine system, we make use of (1) measured concentrations of relevant trace elements (rare earth elements (REEs) and metal(loid)s) in the sediments and waters of the estuary and (2) geochemical modeling which combines mixing and adsorption processes.Our study sheds light on the elemental distribution in the sediments and water in the water-mixing area. As seawater neutralizes the acidity of the river water (pH increases to 6.2) colloids of Fe- and Al-oxyhydroxysulphates (schwertmannite and basaluminite, respectively) precipitate as concentrations of aqueous Fe and Al increase. These phases have a high adsorption capacity and play a critical role in the geochemistry of the aquatic system by retaining Cu, Pb, Cr, As, P, REEs and smaller amounts of Zn, Co, Ni and Mn. The geochemical model reproduces the behaviour of the aqueous REEs, requiring high S/L ratios at pH ≥ 3.5 and participation of sediments and colloids in the reactions to match the field data.The evaluation of the effect of the adjacent phosphogypsum stack on the estuarine geochemistry shows that the stack has a notorious impact on the geochemistry of the surrounding estuarine environment owing to the release of high quantities of phosphate.
Fil: Gutiérrez León, Joan. No especifíca;
Fil: Millán Becerro, Ricardo. Universidad de Huelva. Facultad de Ciencias Experimentales. Departamento de Geología; España
Fil: Carrero, Sergio. No especifíca;
Fil: Pérez López, Rafael. Universidad de Huelva. Facultad de Ciencias Experimentales. Departamento de Geología; España
Fil: Ceballos, Elina Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil; Argentina
Fil: Freydier, Rémi. Université Montpellier II; Francia
Fil: Soler, Josep M.. No especifíca;
Fil: Cama, Jordi. No especifíca;