| 黄河上游白银段煤矿区周边土壤重金属累积特征、污染风险与溯源解析 |
| 摘要点击 580 全文点击 71 投稿时间：2024-04-08 修订日期：2024-06-15 |
| 查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
| 中文关键词 土壤重金属 污染评价 生态风险 聚类分析 正定矩阵因子分解（PMF）模型 |
| 英文关键词 soil heavy metals pollution evaluation ecological hazard cluster analysis positive matrix factorization（PMF） model |
|
| 中文摘要 |
| 为定量评估和精准识别黄河上游干旱-半干旱煤炭矿区周边土壤重金属污染特征、来源及其生态风险,选取白银平川王家山煤矿区为研究对象,通过测定煤矿区周边城镇土壤和农田土壤As、Cd、Cr、Cu、Hg、Ni、Pb和Zn的含量,采用地累积指数法、富集因子法、改进内梅罗综合污染指数法和综合生态风险指数法系统评估土壤重金属污染程度和生态风险,并结合聚类分析和正定矩阵因子分解受体模型精确辨识土壤重金属的污染来源及其贡献率. 结果表明：①研究区周边城镇土壤8项重金属的含量均低于《土壤环境质量建设用地土壤污染风险管控标准（试行）》（GB 36600-2018）中第一类建设用地的风险筛选值,但分别有100%、88.89%、44.44%、22.22%、16.67%、13.89%和2.78%的样点Pb、Hg、Cd、Zn、Cu、As和Cr的含量超过甘肃省土壤背景值；农田土壤8项重金属的含量均低于《土壤环境质量农用地土壤污染风险管控标准（试行）》（GB15618-2018）（pH>7.5）的筛选值,但分别有100%、89.74%、38.46%、25.64%、23.09%、23.08%和17.95%的样点Pb、Hg、Cd、Cu、Zn、As和Ni的含量高于甘肃省土壤背景值. ②周边土壤污染以Hg和Pb为主,总体上为中度污染,但城镇土壤的综合污染程度高于农田土壤；城镇和农田土壤分别处于较强和中等生态风险状态,且Hg是构成周边土壤生态风险的首要元素. ③周边土壤中As受燃煤-农业源和自然源的影响,贡献率分别为40.73%和26.68%,Cd源自于工业源和交通源,贡献率分别为37.07%和26.17%. Cr受35.37%的自然源影响,Cu、Zn受燃煤-农业源和交通源的协同影响,贡献率分别为29.94%、31.41%和41.19%、40.32%,Hg受99.99%的煤矿开采源影响. |
| 英文摘要 |
| To quantitatively assess and accurately ascertain the characteristics, sources, and ecological risks of soil heavy metal pollution in the arid and semi-arid coal mining areas of the upper Yellow River Basin, the Wangjiashan coal mining area in Pingchuan of the Baiyin City was selected for this study. Based on the concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in the soils of the urban areas and agricultural lands around the coal mining region, the geo-accumulation index, enrichment factor, modified Nemerow comprehensive pollution index, and comprehensive ecological risk index were employed to systematically quantify the levels of soil heavy metal pollution and associated ecological risks. Furthermore, cluster analysis and the positive matrix factorization receptor model were jointly utilized to quantitatively explore the sources of soil heavy metals and their respective contribution rates. The results showed： ① The contents of the eight heavy metals in the urban soils around the study area were below the risk screening values for Type I construction land in the “Soil Environmental Quality Risk Control Standard for Soil Pollution of Construction Land （Trial）” （GB 36600-2018）. However, the contents of Pb, Hg, Cd, Zn, Cu, As, and Cr exceeded the soil background values of Gansu Province in 100%, 88.89%, 44.44%, 22.22%, 16.67%, 13.89%, and 2.78% of the samples, respectively. The contents of the eight heavy metals in the agricultural soils were below the screening values for soils with pH > 7.5 in the “Soil Environmental Quality Risk Control Standard for Soil Pollution of Agricultural Land （Trial）” （GB 15618-2018）. Yet, the concentrations of Pb, Hg, Cd, Cu, Zn, As, and Ni exceeded the soil background values of the Gansu Province in 100%, 89.74%, 38.46%, 25.64%, 23.09%, 23.08%, and 17.95% of the examined samples, respectively. ② The soil pollution in the surrounding areas was predominantly characterized by Hg and Pb, overall presenting a moderate level of contamination. However, the degree of comprehensive pollution in urban soils exceeded that of agricultural soils. The urban soils were in a state of relatively high ecological risk, whereas the agricultural soils exhibited a moderate ecological risk. Notably, Hg was the principal hazardous element contributing to the ecological risk of the soils around the study area. ③ In the surrounding soils, the presence of As was impacted by coal combustion-agricultural sources and natural sources, contributing 40.73% and 26.68%, respectively. Cd originated from industrial and transportation sources, with contribution rates of 37.07% and 26.17%, respectively. Cr was affected by natural sources at 35.37%. Cu and Zn were influenced by the combined effects of coal combustion-agricultural sources and transportation sources, with respective contribution rates of 29.94% and 41.19% for Cu and 31.41% and 40.32% for Zn. Hg was predominantly influenced by coal mining activities, accounting for 99.99% of its source. |
|
|
|
