Sustainable remediation of heavy metal contaminated soil through phytostabilization with the in-situ immobilization by mercapto-based palygorskite

This research introduces a novel approach to remediating mining soils contaminated with heavy metals, focusing on the synergistic use of mercapto-based palygorskite (MPAL) and Chrysopogon zizanioides (C. zizanioides) for the phytostabilization of cadmium (Cd) and lead (Pb). While phytostabilization has proven effective in addressing soil contamination, high soil toxicity often limits plant growth and the overall remediation efficiency. Our study offers a unique solution by demonstrating that the application of MPAL not only significantly promotes plant growth but also enhances antioxidant enzyme activity in C. zizanioides, while simultaneously reducing the bioavailability of Cd and Pb in the soil. This combination of MPAL and C. zizanioides resulted in a substantial decrease in heavy metal concentrations in both plant roots and shoots, alongside improvements in soil enzyme activities, including urease, cellulase, and sucrase.Furthermore, our approach also led to increased soil microbial diversity, providing a promising strategy for improving the soil microecology and enhancing long-term sustainability in contaminated environments. These findings offer valuable insights into how MPAL and C. zizanioides can work in tandem to enhance the efficiency of phytoremediation, particularly in soils with high metal toxicity. We believe that this study contributes significantly to advancing environmental remediation practices by offering an effective, sustainable strategy for the immobilization and stabilization of heavy metals in contaminated soils.