BACKGROUND The coexistence of Cd2+ and Zn2+ ions in nature has a significant influence on their environmental behaviors in soils and bioavailability for plants. While many studies have been done on the mutual toxicity of Cd2+ and Zn2+, few studies can be found in the literature focused on the interaction of Cd2+ and Zn2+ on soil clay fractions especially in terms of energy relationship. RESULTS The binding energies of Cd2+ on boggy soil (Histosols) particles and Zn2+ on yellow brown soil (Haplic Luvisols) particles were the highest, while those of Cd2+ and Zn2+ on paddy soil (Inceptisols) particles were the lowest. These results indicated that Cd2+ and Zn2+ have a strong capacity to adsorb in the solid phase at the soil-water interface of boggy soil and yellow brown soil, respectively. However, both Cd2+ and Zn2+ adsorbed on paddy soil particles easily release into the solution of the soil suspension. Unlike the binding energy, the higher adsorption energies of ions in boggy and yellow brown soils showed a weak binding force of ions in boggy soil and yellow brown soil. A 1:1 ratio of Cd2+ to Zn2+ promotes the mutual inhibition of their retentions. Cd2+ and Zn2+ have high mobility and bioavailability in paddy soil and yellow drab soil (Ustalfs), whereas they have high potential mobility and bioavailability in boggy soil and yellow brown soil. CONCLUSION In the combined system, Zn2+ had preferential adsorption than Cd2+ on soil clay fractions. Boggy soil and yellow brown soil have a low environmental risk with lower mobility and bioavailability of Cd2+ and Zn2+ while paddy soil and yellow drab soil present a substantial environmental risk. In the combined system, Cd2+ and Zn2+ restrain each other, resulting in the weaker binding force between ions and soil particles at a 1:1 ratio of Cd2+-Zn2+.

中文翻译：

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Cd / Zn对土壤黏土组分的维恩效应及其相互作用。

背景技术自然界中Cd2 +和Zn2 +离子的共存对其在土壤中的环境行为和植物的生物利用度具有重大影响。尽管已经对Cd2 +和Zn2 +的相互毒性进行了许多研究，但在文献中很少有研究针对Cd2 +和Zn2 +在土壤黏土组分上的相互作用，特别是在能量关系方面。结果Cd2 +在浅土（Histosols）颗粒上的结合能和Zn2 +在黄棕壤（Haplic Luvisols）上的结合能最高，而稻田（Inceptisols）上的Cd2 +和Zn2 +的结合能最低。这些结果表明，Cd2 +和Zn2 +分别在沼泽土壤和黄棕色土壤的土壤-水界面处具有很强的固相吸附能力。然而，吸附在稻田土壤颗粒上的Cd2 +和Zn2 +都容易释放到土壤悬浮液中。与结合能不同，在沼泽和黄棕色土壤中较高的离子吸附能显示出在沼泽和黄棕色土壤中离子的弱结合力。Cd2 +与Zn2 +的1：1比例可促进相互抑制其保留。Cd2 +和Zn2 +在稻田和黄褐土（Ustalfs）中具有较高的迁移率和生物利用度，而在沼泽土和黄棕色土壤中具有较高的潜在迁移率和生物利用度。结论在混合体系中，Zn2 +比Cd2 +对土壤黏土部分的吸附优先。沼泽土壤和黄棕色土壤具有较低的环境风险，Cd2 +和Zn2 +的迁移率和生物利用度较低，而稻田和黄褐色土壤则具有很大的环境风险。在组合系统中，Cd2 +和Zn2 +相互约束，导致Cd2 + -Zn2 +的比例为1：1时离子与土壤颗粒之间的结合力较弱。