Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

作     者：Yingbo Dong Huan Lu Hai Lin Yingbo Dong;Huan Lu;Hai Lin

作者机构：School of Energy and Environmental EngineeringUniversity of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial PollutantsBeijing 100083China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2024年第136卷第2期

页      面：486-497页

核心收录：

学科分类：082803[工学-农业生物环境与能源工程] 07[理学] 08[工学] 0828[工学-农业工程] 0818[工学-地质资源与地质工程] 0903[农学-农业资源与环境] 0804[工学-仪器科学与技术] 0837[工学-安全科学与工程] 0714[理学-统计学（可授理学、经济学学位）] 0835[工学-软件工程] 0701[理学-数学] 0713[理学-生态学] 

基　　金：supported by the National Key R&D Program of China (No.2019YFC1805001) Open Foundation of State Key Laboratory of Mineral Processing (No.BGRIMM-KJSKL2022-07)。 

主　　题：High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment 

摘      要：The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in soil.Its spatial distribution and environment risk assessment are extremely important for the management and remediation of HMs.Eighty soil samples were collected from the high-sulfur CG site in northern China and analyzed for six HMs.The results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment code.The semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of HMs.Fe,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more uniform.The spatial autocorrelation indicated that all HMs had strong spatial heterogeneity.The BCR sequential extraction was employed to qualify the geochemical fractions of HMs.The data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)fractions.Pearson correlation analysis showed that pH was the main control factor affecting the non-residue fractions of HMs.Therefore,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of HMs.Finally,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.