The effects of soil compaction on porosity (α), bulk density (ρs), and saturated hydraulic conductivity (Ksat) can create a physical barrier in the soil, reducing the vertical movement of toxic elements in the soil profile. However, the indirect effects of compaction in altering the forms and availability of heavy metals in soil have not been well-studied. This study examined the influence of compaction on forms of lead (Pb) in soils with contrasting texture. Four levels of compaction were imposed on a sandy loam and a clayey soil, which were artificially contaminated based on their maximum Pb adsorption capacity. Compaction had different effects on Pb forms depending on soil texture. In the sandy loam soil, compaction had a dual beneficial effect in mitigating the impact of Pb contamination, since it decreased Ksat, reducing metal transport to deeper soil layers, and also prevented transformation to more available Pb forms (soluble and exchangeable). Instead, there was an increase in the most environmentally stable forms of Pb (inner sphere adsorption on iron and manganese oxides). In the clayey soil, compaction caused a significant increase in soluble and exchangeable Pb, accompanied by a significant reduction in environmentally stable Pb (inner sphere adsorption on gibbsite and kaolinite). In addition, studies about Pb contents under compacted soil layers should be investigated, mainly in clayey soils with edible crops, and environmental remediation practices that involve the machines traffic (for example, phytoremediation—successive cultivation of Pb-hyperaccumulating plants) should be used with care to minimise the compaction of clayey soils.

土壤压实对孔隙度（α），堆积密度（ρs）和饱和水力传导率（Ksat）的影响可以在土壤中形成物理屏障，从而减少有毒元素在土壤剖面中的垂直运动。然而，压实在改变土壤中重金属的形式和有效性方面的间接作用尚未得到充分研究。这项研究研究了压实对质地相反的土壤中铅（Pb）形式的影响。在砂壤土和黏性土壤上施加了四个等级的压实，这是基于它们的最大Pb吸附能力而被人为污染的。压实对铅形态的影响取决于土壤质地。在沙质壤土中，压实具有减轻Pb污染的双重有益作用，因为它降低了Ksat，减少了金属向更深土壤层的运输，还防止了向更多可用铅形式（可溶和可交换）的转化。取而代之的是，对环境最稳定形式的Pb（铁和锰氧化物上的内层吸附）有所增加。在黏性土壤中，压实导致可溶和可交换的Pb显着增加，同时环境上稳定的Pb（菱铁矿和高岭石上的内球吸附）显着降低。此外，应研究压实土壤层下的铅含量，主要是在有可食用作物的黏土中进行研究，并应采用涉及机器运输的环境修复措施（例如，植物修复—铅超积累植物的成功栽培）。尽量减少粘土的压实。