抄録
Spatial patterns of water quality at 29 sites, in a mixed land use watershed located in southeastern Brazil, were examined for eight metals, sampled over nine years -Arsenic, Cadmium, Copper, Lead, Mercury, Nickel, Selenium, and Zinc. Data analysis included delineation of the area of influence of each monitoring station, based on GIS analysis of Shuttle Radar Topography Mission (SRTM) images, estimation of the upper prediction limit 95% (UPL95) with censored data by the Kaplan-Meier technique, hierarchical cluster analysis (CA), Kruskal-Wallis and Friedman test. The locations of the groups generated by CA agreed with land and soil use and impact of anthropogenic activities. Use of UPL95 as entry data in CA allowed better use and interpretation of monitoring data. Areas with natural background metal-concentration levels in the drainage basin and areas of concern were identified.
