GOU Tizhong, ZHANG Wenhua

(Institute of Resources and Environment, Kaili University, Guizhou Kaili 556011, China)

Abstract: In order to study distribution characteristics, pollution degree, potential ecological risks and pollution sources of heavy metal elements in soil of blueberry planting bases in the Majiang county, Guizhou, concentrations of 8 heavy metals (Hg, Cd, As, Pb, Cu, Ni, Cr and Zn) in 18 soil samples from 6 blueberry planting bases were determined by ICP-MS and AFS methods. The pollution degree and potential ecological risk of these heavy metals in soil of blueberry planting bases was evaluated by approaches of geoaccumulation index, Nemero pollution index, enrichment factor and potential ecological risk index. The source of heavy metals was discussed by correlation analysis and cluster analysis. The results showed that average contents of Hg, Cd, As, Pb, Cu, Ni, Cr and Zn in target soils were 0.24, 0.30, 35, 35, 22, 27, 62, and 79 mg/kg, respectively. The results from geo-accumulation index, Nemero pollution index, enrichment factor, and individual pollution index were similar, Hg, As, and Pb showed varying degrees of pollution. The evaluation results of the comprehensive pollution index method showed that soils of blueberry planting bases in Doupoping, Wukaping, and Baizhulin had been contaminated slightly by heavy metals; soils of blueberry planting bases in Chenjiashan, Wuyangma, and Ganxi had been contaminated moderately by heavy metals. The evaluation results of the potential ecological pollution index showed that potential ecological risks of 8 heavy metals in soils of Doupoping, Wukaping and Baizhulin were slight, and in soils of Chenjiashan, Wuyangma and Ganxi were serious. The correlation analysis and cluster analysis showed that Ni, Zn, Cu, Cr and Cd correlated significantly and might be grouped into one category originated from geological backgrounds; As and Pb correlated very significantly and might be grouped into one category originated from pollutions of animal faeces, pesticides, and automobile exhaust; Hg had no or no significant correlations with other 7 heavy metals and might be originated from coal combustion.

Keywords: Majiang county; blueberry bases; heavy metals; risk assessment

EARTH AND ENVIRONMENT Vol.47, No.5, Tot No.331, 2019, Page 680-688