Influencia de la composición mineralógica sobre la movilidad de elementos traza en suelos agrícolas afectados por explotaciones mineras de la Faja Pirítica Ibérica
- I. González 1
- M. López 1
- A. Romero
- Juan Carlos Fernández Caliani 2
- Pablo Aparicio Ruiz 1
- E. Galán-Perales 1
- 1 Dpto. Cristalografía, Mineralogía y Química Agrícola. Facultad de Química. Universidad de Sevilla
- 2 Dpto. Geología. Facultad de Ciencias Experimentales. Huelva
ISSN: 1576-5172
Year of publication: 2008
Issue Title: VII Congreso Geológico de España
Issue: 10
Pages: 977-980
Type: Article
More publications in: Geotemas (Madrid)
Abstract
In soils close to the abandoned mines of the Iberian Pyrite Belt (SW Spain), agricultural activities have been developed without an assessment of their pollution level. In this work, the mineralogy and the trace element concentration of 37 profiles of agricultural soils have been studied, as well as the chemical and mineralogical speciation to assess the mobility and potential risks. The soils are mainly composed of quartz, feldspars, phyllosilicates and Fe oxy-hydroxides of low “crystallinity”. The <2μm fraction of the samples is composed of illite, kaolinite, chlorite and vermiculite. The chemical analyses display high concentrations in several trace elements (As, Cu, Pb and Zn) and many times they surpass the 90th percentile for the South-Portuguese Zone. The main part of these elements is bounded to the residual fraction being part of sulphides and crystalline Fe oxides. However, some of the Cu, Pb and Zn are associated to mobile phases and they are easily made bioavailable, and this can pose a potential risk for the agriculture.