Abstract: In this study, geoaccumulation index, potential ecological risk index and enrichment factor were used to evaluate the heavy metal pollution of Liaoyang Gongchangling Iron Mine area. The mining area was divided into seven subareas around stope and tailing pond, and soil samples from which were collected. The concentrations of heavy metals, including Cd, Cu, Zn, Pb and Cr in all the samples were measured, based on which the pollution situation was evaluated. The results showed that the evaluation results using the three methods were consistent. The heavy metal pollution in the studied area was serious, mainly caused by Cd and Cu. Cd pollution reached a serious level, Cu was in moderate level, and Zn, Pb and Cr pollution was light. Moreover, the pollution of heavy metals was closely related to human mining activities. The pollution in stope and tailing pond was significantly worse than that in surrounding subareas. More attention should be focused on the pollution of Cd and Cu in the process of ecological restoration and soil reclamation. Our results provide a basis for ecological risk assessment and a scientific reference for the improvement of ecological environment.

Key words: freeze-thaw cycle., fulvic acid, humic acid, humus