Abstract
Multivariate statistical analysis and Cs normalization were used to test methodologies to determine background and anthropogenic influence of metals on river sediments. Total concentrations of nine trace metals (Cd, Cr, Pb, Cu, Ni, Zn, As, Co and Hg) and four reference elements (Cs, Fe, Al and Mn) of sediments in the estuaries of Lan-yang River and Erh-jen River were examined. Trace metals in Lan-yang River are found to be highly correlated with reference elements in the correlation analysis and the principal component analysis. It is found that these trace metals of Lan-yang River could represent one of the distribution characteristics of geogenic metals. The results of statistical analysis show that the trace metals of Erh-jen River may originate from three sources: anthropogenic source for Cd, Cr, Cu, Ni, Zn and Hg, no-distinct-discharge sources for Pb and As, and geogenic source for Co. The correlations between trace metal concentrations and fine-grained fraction were not significant for Erh-jen River. Sites with a high total concentration of trace metals and sites with high Cs-normalized ratio may not coincide. They symbolize different environmental meanings (sediment quality, pollution sources, and regions impacted by sources) and both offer valuable information for pollution control and environmental impact assessment.