[Characteristics of Heavy Metal Pollution, Potential Ecological Risk, and Sources in the Cultivated Soil of Anqing City in the Yangtze River Basin].

Abstract

To investigate the status of heavy metal pollution, potential ecological risks, and sources in the arable soil of the Yangtze River Basin, the surrounding area of Anqing city was selected as the research site. A total of 222 surface soil samples were collected, and the concentrations of eight heavy metals-arsenic （As）, cadmium （Cd）, chromium （Cr）, copper （Cu）, mercury （Hg）, nickel （Ni）, lead （Pb）, and zinc （Zn）-along with soil pH values were analyzed. The pollution characteristics and ecological risks of heavy metals were evaluated using methods, such as the pollution index, geo-accumulation index, and potential ecological risk index. Source apportionment was conducted using the APCS-MLR receptor model. The results indicated that the soils in the study area were primarily acidic. The average concentrations of ω（Cd）, ω（Hg）, ω（As）, ω（Pb）, ω（Cr）, ω（Cu）, ω（Ni）, and ω（Zn） were 0.20, 0.13, 8.18, 32.52, 71.24, 30.44, 33.38, and 100.84 mg·kg^-1, respectively. Except for As, the concentrations of the other elements were all higher than the background values of the Jianghuai Basin. Cd and Hg were identified as the main pollution characteristic factors in the study area, with Hg mostly ranging from slight to moderate pollution and a few samples of Cd at a slight pollution level. The potential ecological risk assessment showed that the area was mostly at a moderate pollution level. Cr and Ni were primarily derived from natural sources； Cd, As, and Pb mainly from agricultural sources； and Hg, Cu, and Zn predominantly from industrial sources. The contributions of natural sources, agricultural sources, industrial sources, and unknown sources to soil heavy metal pollution in the study area were 28.15%, 36.07%, 12.90%, and 22.80%, respectively. The findings provide data support for soil pollution prevention and control measures in the region.