Siyue Li, Quanfa Zhang.  Spatial characterization of dissolved trace elements and heavy metals in the upper Han River (China) using multivariate statistical techniques.  Journal of Hazardous Materials 176 (2010) 579–588

Abstract: A data matrix (4032 observations), obtained during a 2-year monitoring period (2005–2006) from 42 sites in the upper Han River is subjected to variousmultivariate

 statistical techniques including cluster analysis,principal component analysis (PCA), factor analysis (FA), correlation analysis and analysis of variance to determine the spatial

 characterization of dissolved trace elements and heavy metals. Our results indicate that waters in the upper Han River are primarily polluted by Al, As, Cd, Pb, Sb and Se, and 

the potential pollutants include Ba, Cr, Hg, Mn and Ni. Spatial distribution of trace metals indicates the polluted sections mainly concentrate in the Danjiang, Danjiangkou 

Reservoir catchment and Hanzhong Plain, and the most contaminated river is in the Hanzhong Plain. Q-model clustering depends on geographical location of sampling sites and groups the 42 sampling sites into four clusters, i.e., Danjiang, Danjiangkou Reservoir region (lower catchment), upper catchment and one river in headwaters pertaining to water quality. The headwaters, Danjiang and lower catchment, and upper catchment correspond to very high polluted, moderate polluted and relatively low polluted regions, 

espectively. Additionally, PCA/FA and correlation analysis demonstrates that Al, Cd, Mn, Ni, Fe, Si and Sr are controlled by natural sources, whereas the other metals appear to 

be primarily controlled by anthropogenic origins though geogenic source contributing to them.

Keywords: Upper Han River;Trace metals;Multivariate techniques;Cluster analysis;Principal component analysis