Selective uptake of major and trace elements in Erica andevalensis, an endemicspecies to extreme habitats in the Iberian Pyrite Belt

To assess the ecophysiological traits and the phytoremediation potential of the endemic heather Erica andevalensis, we determinedthe concentrations of major and trace elements in di erent plant parts and in rizosphere soils from Riotinto mining district (Huelva,Spain). The results showed that E. andevalensis may grow on substrates with very high As, Cu, Fe and Pb concentrations (up to4114, 1050, 71900 and 15614 g/g dry weight, respectively), very low availability of macro- and micronutrients and with pH valuesranging from 3.3 to 4.9. In these harsh edaphic conditions E. andevalensis selectively absorbed and translocated essential nutrientsand excludes potentially phytotoxic elements, which were accumulated in the root epidermis. The concentrations of major and traceelements in E. andevalensis aerial parts from the Riotinto mining district were in the normal range for plants; likewise other Ericaspecies it accumulated Mn and only in a very polluted site we measured leaf concentrations of As and Pb within the excessive or toxiclimits for plants. Di erently from previous studies, which emphasized the soil pH and bioavailability of phytotoxic elements as themain stress factors, this study showed that in the Riotinto region, E. andevalensis can tolerate wide range of pH and toxic elementconcentrations; the harshest environments colonized by monospecific patches of this species were characterized above all by very lowavailability of nutrients. The extraordinary capability to adapt to these extreme habitats made E. andevalensis a priority species topromote the phytostabilization and the development of a self-sustaining vegetative cover on Riotinto mine tailings.