Phytoremediation potential of native plants: Biomonitoring approach in contaminated soils

Phytoremediation has been used to remediate contaminated site. This study aims to investigate the potential of the selected native plants to accumulate and tolerate chemical pollutants. Two sites were selected in Southern Tunisia lands (Gabes), i) Gannouch located near the chemical industrial complex and ii) Zerkineis around 35 kilometres far from the industrial activities. Soil and plants were sampled and analysed for cadmium (Cd), lead (Pb), copper (Cu), zinc (Zn) and fluorine (F) concentrations. The native plants were Bassia indica and Chenopodium album, with no obvious morphological toxic symptoms. Results indicated that the upper soil layers were alkaline and salt affected with low organic matter content. The highest levels of fluoride and heavy metal were found in Ghannouch. The contents of Cd, Cu, Pb, Zn and F in the roots, stem and leaves of the native plants exceed the normal ranges and the phytotoxic level. Bioconcentration factor (BCF), translocation factor (TF), and biological accumulation factor (BAF) were determined for each element. Based on these factors the selected plants were classified as excluders, indicators, and accumulators for each element. The native plants, studied herein, seems to have significant potential for phytoremediation, thus they may be used as biomonitors in contaminated soils. Bassia indica identified as Cd, Cu and Pb accumulator, could be an excellent candidate for phytoextraction and phyto stabilization because of its F excluder performance.