Synergistic impacts of ferromanganese oxide biochar and optimized water management on reducing Cd accumulation in rice

作者：Qi Tao, Jiahui Liu, Haiyan Zhang, Muhammad Bilal Khan, Youlin Luo, Rong Huang, Yingjie Wu, Qiquan Li, Qiang Xu, Xiaoyan Tang, Changquan Wang, Bing Li · 发表于：Ecotoxicology and Environmental Safety · 年份：2023 · DOI：10.1016/j.ecoenv.2023.115146 · 被引用次数：16 · 研究领域：Heavy metals in environment、Electrokinetic Soil Remediation Techniques、Environmental remediation with nanomaterials

Ferromanganese oxide biochar composite (FMBC) is an efficient remediation material for cadmium -contaminated soils. However, the effect of FMBC under varied water managements on the remediation of Cd-polluted soil is unclear. In this study, we conducted both incubation and field experiments to investigate the combined effects of corn-stover-derived biochar modified with ferromanganese on the immobilization and uptake of Cd by rice under continuous aerobic (A), aerobic-flooded (AF), and flooded-aerobic (FA) water management regimes. The results showed that loading iron-manganese significantly increased the maximum sorption capacity (Qm) of Cd on FMBC (50.46 mg g−1) due to increased surface area, as compared to the pristine biochar (BC, 31.36 mg g−1). The results revealed that soil Eh and pH were significantly affected by FMBC and it’s synergistic application with different water regimes, thus causing significant differences in the concentrations of DTPA-extractable Cd under different treatments. The lowest DTPA-extractable Cd content (0.28–0.46 mg−1) was observed in the treatment with FMBC (2.5 %) combined FA water amendment, which reduced the content of available Cd in soil by 2.63–28.4 %. Moreover, the treatments with FMBC-FA resulted the proportion of residual Cd increased by 22.2 % compared to the control. Variations in the content and fraction of Cd had a significant influence on its accumulation in the rice grains. The FMBC-FA treatments reduced the Cd concentration in r...