Sugarcane Bagasse Biochar Changes the Sorption Kinetics and Rice (Oryza sativa L.) Cadmium Uptake in a Paddy Soil

Today, a variety of techniques are employed to lessen the harmful impacts of soils with high levels of heavy metals. In this case, using biochar is a fairly recent technique to lessen the toxicity of heavy metals. In this study, a pot experiment with a randomized complete block design (RCBD) was carried out to examine the impact of sugarcane bagasse biochar (SBB) on adsorption kinetics and enhancing the growth of rice (Oryza sativa L.) in Cadmium (Cd)-contaminated soil. The variables included planting rice, two levels of Cd (0 and 30 mg kg⁻¹ of soil from CdSO4.8H₂O), and two levels of SBB (0 and 3% by weight). Numerous functional groups on the surface of the biochar may contribute to the immobilization of Cd in polluted soil. According to coefficients of determination (R²), the Langmuir model provided the best fit for the Cd adsorption data of all the studied treatments. The highest plant height was noted when the control soil was treated with SBB. By utilizing 3% SBB, rice height increased by 23.28% over control. Only Cd-contaminated soils resulted in a substantial decline in plant height. By adding 3% SBB in non-contaminated soil, rice grain output and biomass were increased 19.30 and 22.95% over control, respectively. A single application of SBB at a rate of 3% significantly increased biomass and rice grain when compared to single Cd treatments by 16.99 and 20.82%, respectively. The SBB addition to Cd-contaminated soil significantly decreased the DTPA-extractable components of Cd by 40.39% as compared to uncontaminated soil. When compared to untreated soil, SBB treatment considerably reduced the Cd levels in rice plants by 31.60%. Thus, it can be concluded that adding SBB to soil is an appropriate corrective strategy to encourage plant development in soils contaminated with Cd. Understanding how different kinds of biochar interact with contaminated soil to impact Cd uptake in plants requires more research.