Vol18 No.9: 2345-2356
【Title】Transport patterns and numerical simulation of heavy metal pollutants in soils of lead–zinc ore mines
【Author】CAO Jie1; XIE Cheng-yu1*; HOU Zhi-ru2
【Addresses】1 College of Environment and Resources, Xiangtan University, Xiangtan 411105, China; 2 School of Metallurgy and Environment, Central South University, Changsha 410083, China
【Corresponding author】XIE Cheng-yu
【Citation】Cao J, Xie CY, Hou ZR, et al. (2021) Transport patterns and numerical simulation of heavy metal pollutants in soils of lead zinc ore mines. Journal of Mountain Science 18(9). https://doi.org/10.1007/s11629-021-6851-y
【Abstract】Exploring transport patterns of soil contaminants is essential for solvingthe problem of heavy metal contamination in mine soils. In this study, contamination of Pb, Zn, and Cd in the mountain soils of the lead–zinc ore mines in Ganxi Township, Hengdong County, Hunan Province, China was investigated, and their transport patterns werefurther explored usinga soil-column model and numerical simulation techniques. In total, 111 mine soil samples were collected and placedinto sixexperimental soil columns. By controlling the water flow, a control soil column group (CK), two mixed soil columns X1 with daily water flows of 1 and 5 L, and three mixed soil columns X3 with daily water flows of 2, 3,and 4 Lwere evaluated. The results showedthat the residual fraction of Pb accounted for 71.93% of the content on average, whereas the exchangeable fractionsof Zn, Cd,and Fe-Mn oxide-bound fractionsof ZnandCd accounted for 28.60%, 31.07%, and 43.2%and 53.54% of the content, respectively. Pb, Zn,and Cd in the soils of the CK, X1,and X3 groups mainly were accumulated at a depth from approximately 0 to 20 cm, and the content at this depth accounted for 60.09% of that at a 0~40 cm depth. The soil at a depth range of 0~10 cm was most seriously contaminated, and the proportion of content was 32.39% of that at a 0~40 cm depth. Numerical simulation showed that on the 5th day, the pollutant transport range was 0~24 cm, and on the 9th day, the pollutant transport range exceeded 40 cm. On the 15th day, the transport capacity of pollutants at depthsof 0~40 cm wasclose to the stable state, but the soil at a depth of 0~10 cm wasstill heavily polluted. These results reflect the transport pattern of heavy metal pollutants in the soil of lead–zinc ore mines and may provide a reliable scientific support for the prevention of heavy metal contamination in mine environments.
【Keywords】Mountain; Mine soil; Heavy metals; Numerical simulations; Pollutants; Transport patterns.