Status of Ecosystem Services in Abandoned Mining Areas in the Iberian Peninsula: Management Proposal

Abstract

An abandoned sphalerite mining area in the southwest (SW) of the Iberian Peninsula was studied to evaluate the impact that the presence of metal(loid)s has on soil and ecosystem health. Five zones were delimited: sludge, dump, scrubland, riparian zone, and dehesa. Critical total levels of lead (Pb), zinc (Zn), thallium (Tl), and chromium (Cr), well above the limit indicative of toxicity problems, were found in the areas close to the sources of contamination. Pb-Zn concentrations were very high in the riparian zone, reaching values of 5875 mg/kg Pb and 4570 mg/kg Zn. The whole area is classifiable as extremely contaminated with Tl, with concentrations above 370 mg/kg in the scrubland. Cr accumulation mainly occurred in areas away from the dump, with levels up to 240 mg/kg in the dehesa. In the study area, several plants were found growing luxuriantly despite the contamination. The measured metal(loid)s content is the cause of a significant decrease in ecosystem services, resulting in unsafe soils for food and water production, so the implementation of a decontamination program is advisable. The plant species Retama sphaerocarpa, present in the sludge, scrubland, riparian zone, and dehesa, is postulated as suitable for use in phytoremediation.

Editorial for the Special Issue “Phytotoxicity of Heavy Metals in Contaminated Soils”

“…Once contaminated areas re delimited, it is necessary to know the distribution of metals in the area, as they can condition the distribution of vegetation in terms of cover, plant structures and diversity. In this sense, González-Morales and co-authors [ 3 ] analyse the distribution pattern of metals (Pb, Zn, Tl and Cr) in an abandoned sphalerite mining area using Geographic Information Systems, allowing the geographical identification of the contamination source areas and their influence on the vegetation cover, as well as identifying metal-accumulating species such as Q. rotundifolia Lam, S. holochoenus (L.) Soják, Carlina ssp . L. and R. sphaerocarpa (L.) Boiss.…”