Geostatistical analyses of iron in shallow groundwater and their application for establishing an environmental baseline: a case study

Knowledge of the environmental background and a baseline are important for local environmental studies and management. In this study, seventy groundwater samples taken near the city of Suzhou, northern Anhui Province, China have been measured for their iron concentrations, and the results processed by geostatistical analytical techniques (including semi-variance, spatial autocorrelation and cluster analyses). The results indicate that the quality of these groundwater samples is relatively good, and all can be classified as class one according to their iron concentrations and the groundwater quality in China. The spatial distribution of iron concentrations shows that they increase from north to south in the area. The semi-variance, spatial autocorrelation and cluster analyses suggest that iron concentrations in the shallow groundwater were affected by combined natural and anthropogenic contributions. After removing the spatial outliers, the environmental baseline of iron in the shallow groundwater in the study area is established as being 0–28.5 μg/l.