DBPapers
DOI: 10.5593/SGEM2014/B51/S20.046

HEAVY METALS ACCUMULATION IN SOIL AND PLANTS IN A LEAD OLD MINE: PROSPECTS FOR PHYTOREMEDIATION

J. Pratas, P. Favas, R. D’Souza, M. Varun, M. Paul
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-17-9 / ISSN 1314-2704, June 19-25, 2014, Book 5, Vol. 1, 339-346 pp

ABSTRACT
The potential for colonization of highly contaminated soils revealed by native species can be very interesting because it constitutes a natural attenuation of contamination until they are taken advanced decontamination processes.This study aimed to assess the phytoremediation potential of the flora found growing on lead (Pb) enriched soils in an abandoned Pb mine in Central Portugal. In mineralized veins zone the soil Pb concentrations averaging 2380 mg/kg and reaching 9330 mg/kg. Lead concentrations in plants ranged from 1.11 to 548 mg/kg. Significant accumulation of Pb was seen in Cistus salvifolius, Lonicera periclymenum, Anarrhinum bellidifolium, Phytolacca americana, Digitalis purpurea, Mentha suaveolens, Polystichum setiferum, Pteridium aquilinum, and Asplenium onopteris. In non mineralized zone, Pb content was not significant, ranging from 0.94 to 11.6 mg/kg. However, concentrations higher than toxic level in some species like C. salvifolius, D. purpurea, L. periclymenum, A. bellidifolium, P. americana indicate that internal detoxification metal tolerance mechanisms might also exist; therefore, their utility for phytoremediation is possible. Though at first glance maximum Pb content observed in trees like Acacia dealbata, Olea europaea, and Quercus suber from mineralized zone is not very promising compared to that of smaller plants mentioned above, nevertheless these trees can be very effective due to their enormous biomass.

Keywords: Abandoned mine, Barbadalhos mine, Bioaccumulation, Phytoextraction