不同磷酸盐对铜和锌在红壤中吸附和淋溶的影响

摘要

Batch and soil column experiments were conducted to evaluate the influence of KH2PO4, (NH4)H2PO4and Ca(H2PO4)2on the adsorption and leaching characteristics of Cu and Zn in red soil. The results show that all the three phosphates can greatly improve the adsorption capacity of red soil for Cu and Zn, and the effect of different phosphates on Cu and Zn adsorption follows the order of Ca(H2PO4)2>KH2PO4>(NH4)H2PO4. The addition of phosphate has little effect on the mobility of Cu. Ca(H2PO4)2and (NH4)H2PO4 show a strong ability in immobilizing Zn while the immobilization ability of KH2PO4 is much weaker. All the three phosphates are helpful for modifying the partitioning of Cu and Zn from the non-residual phase to the residual phase; however, they could also enhance the contents of Cu and Zn associated with exchangeable and carbonates fractions.%采用批式吸附实验和土柱实验研究KH2PO4、(NH4)H2PO4和 Ca(H2PO4)2对铜和锌在红壤中的吸附和淋溶特性。结果表明：这3种磷酸盐都能极大地提高红壤对铜和锌的吸附能力，其影响大小顺序为 Ca(H2PO4)2> KH2PO4>(NH4)H2PO4。磷酸盐的添加对铜的迁移性影响不大。Ca(H2PO4)2和(NH4)H2PO4能较大地提高锌在红壤中的移动性。3种磷酸盐都能促进铜和锌的形态由非残渣态向残渣态转化，但是同样会增加其可交换态和碳酸盐结合态的含量。