Meng Zhuowen, Huang Shuang, Mu Wenting, Wu Jingwei, Lin Zhongbing
State Key Laboratory of Water Resources and Hydropower Engineering Sciences, Wuhan University, Wuhan, 430072, China.
Environ Sci Pollut Res Int. 2023 Apr;30(16):47221-47233. doi: 10.1007/s11356-023-25342-9. Epub 2023 Feb 3.
In this study, cadmium (Cd) transport and immobilization on passivators (biochar, organic fertilizer) and soils under saturated-unsaturated conditions were independently analyzed. The results showed that the Cd adsorption capacities of biochar and organic fertilizer were comparable in acidic soils. But in alkaline soils, the Cd adsorption capacity of organic fertilizer was significantly larger than that of biochar. In acidic soils, passivators effectively immobilized Cd, and the total net effects were in the order: combination (44.05-58.13%) > 3% biochar (31.96-46.88%) > 3% organic fertilizer (28.78-41.82%). In alkaline soils, all treatments had negative effects on Cd immobilization. For acidic soils, the immobilization of Cd was mainly attributed to the passivators, and the positive contribution percentages of relatively stable Cd increase by passivators were 81.05-100%, while those by soils were 0-18.95%. For alkaline soils, after the treatments of passivators, although a considerable amount of Cd was immobilized inside the passivator, Cd was activated more inside the soil. Therefore, it is noteworthy that soil conditions must be fully considered when applying biochar and organic fertilizers for Cd remediation.
本研究分别分析了饱和-非饱和条件下镉（Cd）在钝化剂（生物炭、有机肥）及土壤上的迁移和固定情况。结果表明，在酸性土壤中，生物炭和有机肥对Cd的吸附能力相当。但在碱性土壤中，有机肥对Cd的吸附能力显著大于生物炭。在酸性土壤中，钝化剂能有效固定Cd，总净效应顺序为：组合（44.05-58.13%）>3%生物炭（31.96-46.88%）>3%有机肥（28.78-41.82%）。在碱性土壤中，所有处理对Cd固定均有负面影响。对于酸性土壤，Cd的固定主要归因于钝化剂，钝化剂使相对稳定的Cd增加的正向贡献百分比为81.05-100%，而土壤的贡献百分比为0-18.95%。对于碱性土壤，经过钝化剂处理后，虽然有相当数量的Cd固定在钝化剂内部，但土壤内部的Cd被更多地活化。因此，在应用生物炭和有机肥进行Cd修复时，必须充分考虑土壤条件，这一点值得注意。
