Cadmium (Cd) and other heavy metals usually coexist in soils. Effects of coexisting heavy metals on the accumulation and transfer of Cd in field soils by wheat remain poorly understood. Here we revealed changeable effects of coexisting Pb, Zn and Cu on the Cd transfer from soils to wheat grains. Soil burdens of Cd were found to exhibit positive correlations (r = 0.459–0.946) with those of coexisting Pb, Zn and Cu (particularly Pb). Effects of three coexisting metals on to the uptake of Cd by wheat varied in the directions and/or extents with types of metals and transfer processes of Cd. Coexisting Zn inhibited the uptake of Cd by wheat grains to higher extent than Pb and Cu. Soil Zn, along with soil Cd, soil pH and soil Ca, was used to construct the predictive model of grain Cd (R² = 0.868). External verifications of the model on 572 datasets of large representation performed well. The predictive accuracy was about 54%, 73% and 89% for a factor of 1, 2 and 5 above and below the ideal fit, respectively. This finding has practical interest in risk assessments and remediation measures of Cd-contaminated soil sites in regional scales.

镉 (Cd) 和其他重金属通常共存于土壤中。共存重金属对小麦在田间土壤中积累和转移 Cd 的影响仍然知之甚少。在这里，我们揭示了 Pb、Zn 和 Cu 共存对 Cd 从土壤向小麦籽粒转移的变化影响。发现 Cd 的土壤负荷与共存的 Pb、Zn 和 Cu（尤其是 Pb）的土壤负荷呈正相关（r  = 0.459-0.946）。三种共存金属对小麦吸收Cd的影响在方向和/或程度上随金属类型和Cd迁移过程的不同而不同。Zn 共存抑制小麦籽粒吸收 Cd 的程度高于 Pb 和 Cu。土壤Zn与土壤Cd、土壤pH值和土壤Ca一起用于构建谷物Cd( R ²= 0.868）。该模型在 572 个大型数据集上的外部验证表现良好。对于高于和低于理想拟合的因子 1、2 和 5，预测准确度分别约为 54%、73% 和 89%。这一发现对区域范围内 Cd 污染土壤场地的风险评估和修复措施具有实际意义。