Simultaneous alleviation of Sb and Cd availability in contaminated soil and accumulation in Lolium multiflorum Lam. After amendment with Fe–Mn-Modified biochar

Abstract In this study, we assessed the capacities of biochar derived from tea branches (hereafter referred to as biochar) and Fe–Mn-modified biochar (MnFe 2 O 4 -biochar) to immobilize Sb and Cd in contaminated soils and reduce the bioavailability of Sb and Cd in Lolium multiflorum Lam. . The results of pot experiments indicated that the application of biochar and MnFe 2 O 4 -biochar significantly (P  2 O 4 -biochar, whereas biochar amendment only effectively reduced the extractable Cd content. Sequential extraction analysis demonstrated that the exchangeable Sb and Cd were transformed into less accessible forms, effectively reducing their toxicity, after addition of MnFe 2 O 4 -biochar. Finally, amendment with MnFe 2 O 4 -biochar significantly (P  Lolium multiflorum Lam. , subsequently reducing their phytotoxicity. Our findings suggest that MnFe 2 O 4 -biochar may be used for the low-cost, effective, and eco-friendly passivation of Sb and Cd in co-contaminated soil.