Analysis of influencing factors of heavy metals pollution in farmland-rice system around a uranium tailings dam

Abstract

Due to the limitation of special regions, few studies have combined the environmental pollution around uranium tailings dams and heavy metal pollution in farmland. The study aimed to analyze the pollution status and causes of U, Cd, Cr, Pb, Cu, Zn, As, and Hg in the farmland-rice system around a uranium tailings dam. It was found that Cr, Pb, Cu, and Zn exceeded the standards. The principal component analysis method was used to determine that there were three sources of heavy metals in the region: road transportation, human intervention, and natural background. The results of chemical speciation analysis showed that the pollution of Pb, Cu, and Zn needed to be vigilant. pH and SOM had a greater impact on them. A regression model was established to investigate the cause of heavy metal accumulation in rice, and it was found that various parts of rice were greatly affected by pH. The main reason for the current status of the study area was not the pollution input of the uranium tailings dam itself, but human activities. Improving the local soil acidity was of great significance for controlling local pollution problems and protecting residents' health.