The role ofpH and soil buffer capacity in heavy metal retention in clay soils

he concept of soil buffer capacity was used in this study to investigate the capacity of soil to attenuate heavy metals when acid is involved in the soil system. The buffer capacity of soil in this study was found to depend mainly on carbonate content and cation exchange capacity (C.E.C.) of soils. The magnitude of buffer capacity followed the order: illite ;The relation of soil buffer capacity and heavy metal retention and movement in the clay soils found from this study revealed that the soil buffer capacity was a parameter that can be used in the prediction and prevention of heavy metal migration in soil. The soil buffer capacity is recommended as a parameter that should be included in the determination of soil properties particularly for the purpose of land application and disposal of wastes with leachates that could contain heavy metals. (Abstract shortened by UMI.);The study of heavy metal retention in soils was performed both by soil suspension test and soil column test. The results showed that as soils received increasing amounts of acid, high amounts of heavy metals (particularly Pb and Cu) could still be retained if the soils had a high enough buffer capacity to resist a change in pH such that it will not drop to...