It is necessary to study the pollution characteristics of heavy metals with different particle sizes in road-deposited sediments in order to control heavy metal contamination in urban road-deposited sediments. Forty-eight samples from six areas in Nanjing were analyzed for Pb, Cr, Zn, Cu, Mn, Cd, and Ni. The heavy metal content of various road functional areas was analyzed. The average heavy metal concentrations were compared with soil background values. The results indicated that the mean concentrations of Cu, Zn, Pb, Cr, Cd, and Ni were respectively 7.44, 13.89, 15.05, 3.23, 29.35, and 2.71 times the soil background values, but that the mean Mn concentration was lower than the soil background value. pH analysis of road-deposited sediments showed that the sediment pH was generally greater than 7, meaning that road-deposited sediment was alkaline. The seasonal variation pattern of sediment pH was as follows: spring < winter < autumn < summer. Analysis of the correlations between heavy metals in the roaddeposited sediments indicated that the correlations of heavy metals between different functional areas were not very obvious, which showed that the sources of heavy metals in road-deposited sediments are more complex than anticipated. The concentration enrichment ratio was used to assess the degree of impact of human activities on metal contamination. The concentration enrichment ratios (CERs) of heavy metals were ordered as follows: Cd > Pb > Zn > Cu > Cr > Ni. To analyze the potential water environmental risk of heavy metals in sediments, the heavy metal content of a 0.5M HCl cleaning solution was analyzed and showed that the heavy metals were mostly in particulate form.
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