Trace element accumulation in plants from an aridic area affected by mining activities

Trace element contamination has been a serious problem in the vicinity of abandoned mine sites. In the studied area, mining activities have produced great amounts of wastes, characterized by high trace elements content, acidic pH and minerals from supergene alteration. Trace elements have been dispersed, both downstream and downslope from the mine mainly due, mainly, to surface run-off. Trace elements hydric mobilization usually takes place during the rainy season, an important pollution route in the studied area. A wide range of techniques have been proposed to remediate soils polluted by trace elements. Among them, phytoremediation-based technologies could provide a long-lasting solution. The aim of this work was to determine trace element concentration in roots and leaves of five plant species (Limonium carthaginens, Arthrocnemum macrostachyum, Dittrichia viscosa, Glaucium flavum and Zygophyllum fabago) growing in soils polluted by mining activities in order to determine which part of the plants accumulate heavy metals to the greatest extent. The metal concentrations in plants varied with plant species. Plant accumulation results showed that Z. fabago could act as an accumulator for Fe, and A. macrostachyum could accumulate in Fe, As and Mn. The other plant species collected from the mining sites were tolerant to trace element contamination.

► Mining activities have resulted in wastes with a high content of trace elements.
► Zygophyllum fabago accumulates Fe.
► Arthrocnemum macrostachyum accumulates Fe, As and Mn.
► Other plants collected from the mining sites were tolerant to trace elements.