Horák J., Hejcman M. (2016): Contamination characteristics of the confluence of polluted and unpolluted riversrange and spatial distribution of contaminants of a significant mining centre (Kutná Hora, Czech Republic). Soil & Water Res., 11: 235−243.The study brings new insights into the topic of the contamination characteristics of the mining region of Kutná Hora (Central Bohemia). The previous meta-analysis of the contamination studies showed that there could be a surprisingly low spatial range of contaminated river sediment downstream of Kutná Hora. The study should answer the question as to whether it is justifiable to interpret the presence of contaminants as a result of Kutná Hora mining. There was found a rapid increase in concentrations between the background area and contaminated Kutná Hora. Increase of medians (in mg/kg) of As: 33 and 148, Cu: 34 and 57, Pb: 35 and 82, Zn: 85 and 232; means increased ca 10 times. Then a decrease between the contaminated area and the confluence area was observed. But this decrease was influenced by the presence of extreme values in the contaminated area and therefore it was observed only in means. Medians of the elements concentrations did not decrease. The concentrations of the elements decreased after the confluence to lower values, but they stayed at the contaminated area levels. The background levels were observed only in the probes related to Labe alluvium. But also in these probes, the contamination was traced by multivariate analyses -by clear separation of As, Cu, Pb, Zn from other elements. The contamination was manifested in probes after the confluence mainly in the topsoil levels of alluvium, ca. in 10 to 40 cm. The original starting point of this study, that the contamination is not firmly manifested in the areas after the confluence, based on meta-analysis of regional studies, is not valid.Keywords: 3D analysis; magnetic susceptibility; pollutant distribution; river sediments; spatial analysis; trace elements Many studies concern rivers and their alluvia as an important environment for both transport and the storage of metal contaminants (e.g. Macklin & Klimek 1992;Brewer & Taylor 1997;Miller 1997;Bird et al. 2005;Raab et al. 2005;Ettler et al. 2006;Knox 2006;Hilscherová et al. 2007;Taylor & Owens 2009;Martin 2015). The storage can be long term (Tylecote 1987;Grattan et al. 2007). Floodplain storage can be changed into a contamination source, e.g. by its erosion (Gäbler & Schneider 2000;Coulthard & Macklin 2003; Craddock & Lang 2003;Förstner et al. 2004;Hürkamp et al. 2009a). Some studies focus on contamination distribution in both horizontal and vertical dimension, but they are few (e.g. Park & Vlek 2002;Dennis et al. 2009;Hürkamp et al. 2009b). The region of Kutná Hora was a significant centre of mining and smelting (especially from the 13 th to the 16 th century -see Kořan 1950;Bartoš 2004) and therefore it is strongly contaminated, mainly by As, Cu, Pb, and Zn. These contaminants can be divided into subgroups of As, of Cd, and of Cu, Pb and Zn
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