Forty-two soil and road dust samples were collected near Echigo line around Niigata and analyzed to investigate the impact of railway and automobile operation on heavy metal aggregation. ICP-MS was applied to measure concentrations and distribution of Cr, Co, Ni, Cu, Zn, As, Sr, Cd, Sn, and Pb. Spearman correlation, principal component analysis, cluster analysis and Pb stable isotope analysis were employed to investigate their potential sources. The results reflected that both railway and road had influence on heavy metals's concentration and distribution. In the soil samples, concentration of Cu, Zn, Sn and Pb had exceeded soil background value of Japan. Their highest concentrations were 26.5, 12.4, 11.0 and 52.7 times more than the background value. In all road dust samples, concentration of all heavy metals, except Co and Ni, had exceeded the background value. Concentrations of Cr, Ni, Cu, Sn and Pb decreased as the distance to railway increased, indicating that their concentrations were affected by the railway operation. Concentrations of Cr, Cu, Zn, As, Sr, Sn and Pb decreased as the distance to railway increased, indicating their concentrations were affected by automobile. Spearman correlation analysis showed Cu, Zn, Sn and Pb had significant positive relation with each other, indicating they could have a similar source. Principal component analysis showed that their concentrations were affected by two factors, i.e., railway and automobile operation. Cluster analysis further confirmed such relationship between Cu, Zn, Sn and Pb. Pb stable isotope analysis showed that concentration of Pb was influenced by both railway and automobile operation. Therefore, Cu, Zn, Sn and Pb might be originated from both railway and automobile operation in the study.%以日本新潟县新潟市越后线沿线土壤和道路粉尘为研究对象,在铁路和道路沿线共采集土壤和道路粉尘样品42份,分析铁路及道路对沿线环境重金属含量的影响,对城市中土壤重金属污染来源进行探析,为城市重金属污染防控提供理论依据.经消解实验后,使用电感耦合等离子体质谱仪测定Cr、Co、Ni、Cu、Zn、As、Sr、Cd、Sn和Pb含量,分析新潟市越后线沿线土壤、道路粉尘重金属含量,以及重金属含量在铁路和城市道路沿线的空间分布特征,并对重金属来源进行判别.结果表明,铁路和公路对土壤中重金属的含量及分布都有影响.越后线土壤样品中Cu、Zn、Sn和Pb均超出日本土壤背景含量值,最大值分别为背景值的26.5、12.4、11.0和52.7倍,且变异系数分别为139%、67.5%、120%和219%,达到了重度变异程度.道路粉尘样品中除Co和Ni外,其他元素在所有采样点的含量都超过了背景值;Cr、Ni、Cu、Sn和Pb含量随着与铁路距离的增加而降低,且最高含量基本出现在距离铁路0~5 m 范围内,说明这些元素含量受到铁路运行的影响.Cr、Cu、Zn、As、Sr、Sn 和 Pb 含量随着与道路距离增加而降低,且最高浓度基本出现在道路粉尘中,说明这些元素含量受到城市道路运行的影响.相关分析表明,Cu、Zn、Sn 和 Pb 之间存在显著性正相关,推测其具有共同的污染源.主成分分析表明,Cu、Zn、Sn和Pb在成分1(贡献率42.99%)上正荷载较高,而在成分2(贡献率31.04%)上均为负荷载,在两种成分上的不同荷载表明这4种元素含量同时受到两种因素的影响.系统聚类分析表明,这4种元素在距离为5处被聚为一类,其含量具有明显的相关性.Pb稳定同位素法表明,土壤和粉尘样品中Pb来源为机动车和铁路两种人为源.因此,Cu、Zn、Sn和Pb含量同时受到铁路和城市道路运行的影响.
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