Effective Phytoremediation of Soil Contamination through Native Iranian Hyperaccumulator Plant Species

Addressing the growing issue of soil contamination requires identifying effective hyperaccumulator plant species, which are essential for the success and efficiency of phytoremediation. These unique plants can absorb and sequester metals at concentrations significantly higher than typical flora, offering a sustainable and eco-friendly solution. Phytoremediation, as the primary approach in this study, was explored to identify potential candidates for phytoextraction and phytostabilization among seven native plant species growing on manganese (Mn)-bearing soils derived from ultramafic rocks in the Abadeh-Tashk ophiolite complex, Iran. E. stellata was a promising Mn-hyperaccumulator suitable for phytoextraction in contaminated areas. In contrast, species like C. intricata , O. persica , and A. fasciculifolius exhibited high bioconcentration factors (BCFs) alongside low translocation factors (TFs), suggesting their potential for Mn phytostabilization. Further analysis of individual elements revealed that these species, with BCF > 1 and TF < 1, were also suitable candidates for Cu phytostabilization. Additionally, C. intricata demonstrated strong nickel (Ni) accumulation, indicating its suitability for Ni phytostabilization. The study also examined factors influencing Mn uptake, including soil characteristics such as CaCO ₃ content, exchangeable Mn fraction, pH, organic matter (OM), soil texture, and cation exchange capacity (CEC). Results indicated that low CaCO ₃ content and alkaline soil pH enhanced Mn uptake, while clay loam texture and low OM limited Mn bioavailability, hindering its uptake by plants. This comprehensive investigation into Mn uptake and the identification of suitable plants for phytoremediation in the Abadeh-Tashk region offered valuable insights into the capabilities of hyperaccumulators in mitigating soil metal contamination. The study not only contributed to the understanding of environmental science but also provided promising solutions for soil restoration projects on a global scale.