title: Sediments as monitors of heavy metal contamination in the Ave river basin (Portugal): multivariate analysis of data.
abstract: The concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn) were determined in river sediments collected at the Ave river basin (Portugal) to obtain a general classification scenery of the pollution in this highly polluted region. Multivariate data analysis techniques of clustering, principal components and eigenvector projections were used in this classification. Five general areas with different polluting characteristics were detected and several individual heavy metal concentration abnormalities were detected in restricted areas. A good correlation between the overall metal contamination determined by multivariate analysis and metal pollution indexes for all sampling stations was obtained. Some preliminary experiments showed that the metal concentrations normalised to the volatile matter content in the sediment fraction with grain size <63 microm seems to be an adequate method for assessing metal pollution.
authors.affiliation: CTQAA-Center of Chemical, Environmental and Food Technology, Department of Chemical Engineering, Faculdade de Engenharia, Universidade do Porto, P4099 Porto Codex, Portugal.
authors.forename: H M
authors.initials: HM
authors.lastname: Soares
authors.forename: R A
authors.initials: RA
authors.lastname: Boaventura
authors.forename: A A
authors.initials: AA
authors.lastname: Machado
authors.forename: J C
authors.initials: JC
authors.lastname: Esteves da Silva