[Heavy Metal Pollution Characteristics and Ecological Risk Assessment of Kafang Tin Tailings Pond]

To study the pollution characteristics and ecological risks of heavy metals in tailings ponds is an important prerequisite for protecting the surrounding environment and human health. The total amount and morphology of five "toxic" heavy metals （As, Cr, Cd, Pb, and Hg） in Kafang tin tailings pond were determined. Based on the aforementioned, we analyzed the distribution characteristics of heavy metals. The potential ecological risks of heavy metals in tailings ponds were studied from the aspects of total amount and morphology. Sample data were analyzed using the geo-accumulation index method, potential ecological risk assessment method, and risk assessment criteria. The results showed that, from the perspective of the total amount of heavy metals, the spatial distribution of As was different, and the pollution was serious； the spatial distribution of Cd, Hg, Cr, and Pb was relatively uniform； the pollution of Cd and Hg was slight； and the pollution of Cr and Pb was controllable. From the perspective of the morphology of heavy metals, As, Cr, Pb, and Hg in tailings were mainly in the residual state and had low environmental pollution risk, whereas Cd in tailings was mainly in an oxidizable state and had high environmental pollution risks. Therefore, Kafang tin tailings pond should strengthen the control of As in tailings and pay attention to the potential pollution risks of Cd in tailings and the overall pollution risks of Hg, Pb, and Cr in the entire reservoir were controllable.