Manganese (Mn) is widely used to control cadmium (Cd) and arsenic (As) uptake by rice, but the effects of different Mn forms and concentrations on Cd/As movement in the soil-rice system are unclear. The study investigated the mechanisms by which three Mn compounds affected the accumulation of Cd/As in rice under different application rates. MnO 2 , MnSO 4 , and MnCO 3 treatments significantly reduced grains Cd levels by 27.6 %, 30.2 %, and 28.1 %, respectively, while As levels were less consistently affected. Three forms of Mn fertilizers enhanced the conversion of exchangeable to carbonate bo...