Increasing of municipal solid wastes as well as many urban difficulties are serious threats to the environment and public health. These problems in addition to soil and water resources pollution are needed to be attended seriously. Harmful compounds such as heavy metals through crop uptake can enter to the life cycle and threat human health. The objective of this research was to study the heavy metal distribution such as cadmium, lead, and zinc in different soil depths to maximum 30 cm. So, three soil treatments including undisturbed (U), disturbed (D), and disturbed with three percent of organic matter (O) with three replication were prepared and leached by 20 mg/l of cadmium, lead, and zinc solutions for one month. In the end of experiment, the total concentration of any metal was measured in different soil depths. The results showed that there was a significant difference between metal type at 1%, and accumulation or adsorption trend of heavy metals were Zn>Pb>Cd in this soil. Also, the concentration of cadmium and lead were highest mounts in U treatment and their concentrations were lowest amounts in O treatment, but zinc concentration was highest in D treatment. In addition, the highest amounts of elements were observed at the soil surface which decreased in deeper depths. Although the highest amounts of lead and cadmium accumulation were in the depth of four to six centimeters in U treatment, but the highest amounts of three elements in D and O treatments were observed from soil surface to the depth of two centimeters. The results of U treatment in comparison to other treatments reflect the effect of preferential flow on metal transport in soil surface (upper four centimeter) and decreasing and disconnection of macropores in deeper depths in.

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