This report describes an application of principal component analysis to heavy metal contents (Cu, Cr, Zn, Pb, Cd, Ni), HNO3-H2O2 soluble metals in the upstream sediments and 0.5 N HCl soluble ones in the downstream sediments. Two principal factors were extracted, and a comparison was made between the distribution of heavy metals on the plane produced by two factor loadings and that of rivers on the plane produced by two factor scores.Results show that the first factor represents the general pollution by heavy metals. The second factor in HNO3-H2O2 soluble heavy metals in the upstream sediments represents an axis of siderophilechalcophile element from the standpoint of geochemistry, while the second factor in 0.5 N HCl soluble heavy metals in the downstream sediments represents an axis of adsorbable-unadsorbable element in sediment from the standpoint of artificial heavy metal pollution.
/ Bottom mud was collected from the upper and lower reaches of 92 rivers in Japan to determine the distribution of 0.5N-HCI-soluble heavy metals. The average concentrations of Cu, Zn, Pb, and Cd in the mud from the lower reaches were from two to three times higher than those in the upper reaches. Japanese rivers were classified according to the degree of heavy metal pollution by using the values of 0.5N-HCI-soluble metals in the lower reaches of rivers. The content of 0.5N-HCI-soluble heavy metals in the mud of the upper reaches was used as the standard value. The classification of rivers was made by a cluster analysis according to Euclidian distance. As a result, rivers in Japan could be classified into three groups based on the degree of metal pollution, and the classification was in agreement with the pollution index.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.