Novel magnetite nano-rods-modified biochar: a promising strategy to control lead mobility and transfer in soil-rice system

Environment-friendly and cost-effective remediation strategies are highly needed to reclaim the lead (Pb) contaminated soils. The present study evaluated the efficacy of novel magnetic wood-modified biochar (MWB) and pristine wood biochar (WB) at different application rates (0.5-1.75%) for remediation of Pb-contaminated soil. Both MWB and WB amendments effectively reduced the transfer and bioavailability of Pb in the soil. MWB (1.75%) amendment remarkably influenced rice plant growth in terms of improved biochemical and physiological attributes. The amendment of Pb-contaminated soil with MWB also proved beneficial in reducing oxidative stress in rice plants. A significant increase in root iron plaque (Fe-plaque) formation was also observed with 1.75% MWB treatment. The sequential extraction results demonstrated the increased transformation of exchangeable Pb fractions to non-exchangeable Pb fractions. Application of 1.75% MWB reduced the Pb content in roots and shoots by 48.6% and 60.2%, respectively. Present findings clearly validated the usefulness of MWB as a cost-effective remediation strategy for Pb-contaminated soil.

Automated summary

The study evaluated the efficacy of novel magnetic wood-modified biochar (MWB) and pristine wood biochar (WB) for the remediation of lead (Pb) contaminated soils. Results showed that both MWB and WB effectively reduced the transfer and bioavailability of Pb in the soil, with MWB significantly improving rice plant growth and reducing oxidative stress in the plants.