Soil pollution indices conditioned by medieval metallurgical activity e A case study from Krakow (Poland) * Joanna Kowalska a, * , Ryszard Mazurek a , Michal Ga ˛ siorek a , Marcin Setlak b , Tomasz Zaleski a , Jaroslaw Waroszewski c a Department of Soil Science and Soil Protection, University of Agriculture in Krakow, Al. Mickiewicza 21, 31-120 Krak ow, Poland b Department of Physics, University of Agriculture in Krakow, Al. Mickiewicza 21, 31-120 Krak ow, Poland c Institute of Soil Science and Environmental Protection, Wroclaw University of Environmental and Life Sciences, Grunwaldzka 53, 50-357 Wroclaw, Poland article info Article history: Received 1 March 2016 Received in revised form 12 August 2016 Accepted 21 August 2016 Available online xxx Keywords: Medieval industry Lithological discontinuity Cultural layers Pollution indices Heavy metals Urban soils abstract The studied soil proﬁle under the Main Market Square (MMS) in Krakow was characterised by the in- ﬂuence of medieval metallurgical activity. In the presented soil section lithological discontinuity (LD) was found, which manifests itself in the form of cultural layers (CLs). Moreover, in this paper LD detection methods based on soil texture are presented. For the ﬁrst time, three different ways to identify the presence of LD in the urban soils are suggested. The presence of LD had an inﬂuence on the content and distribution of heavy metals within the soil proﬁle. The content of heavy metals in the CLs under the MMS in Krakow was signiﬁcantly higher than the content in natural horizons. In addition, there were distinct differences in the content of heavy metals within CLs. Proﬁle variability and differences in the content of heavy metals and phosphorus within the CLs under the MMS were activity indicators of Krakow inhabitants in the past. This paper presents alternative methods for the assessment of the degree of heavy metal contamination in urban soils using selected pollution indices. On the basis of the studied total concentration of heavy metals (Zn, Pb, Cu, Mn, Cr, Cd, Ni, Sn, Ag) and total phosphorus content, the Geoaccumulation Index (I geo ), Enrichment Factor (EF), Sum of Pollution Index (PI sum ), Single Pollution Index (PI), Nemerow Pollution Index (PI Nemerow ) and Potential Ecological Risk (RI) were calculated using different local and reference geochemical backgrounds. The use of various geochemical backgrounds is helpful to evaluate the assessment of soil pollution. The individual CLs differed from each other according to the degree of pollution. The different values of pollution indices within the studied soil proﬁle showed that LDS should not be evaluated in terms of contamination as one, homogeneous soil proﬁle but each separate CL should be treated individually. © 2016 Elsevier Ltd. All rights reserved. 1. Introduction Soils in urban areas are composed of accumulated materials of natural and artiﬁcial origin. The accumulation of anthropogenic materials over hundreds of years on the surface of natural soil forms a speciﬁc strata deﬁned in the literature as cultural layers (CLs) (Alexandrovskaya and Panova, 2003; De ˛ biec and Pelisiak, 2008; Lorenz and Kandeler, 2005; Ma zeika et al., 2009; S andor and Szab o, 2014; Shaw et al., 2010). Usually, in the proﬁle of ur- ban soil a clear difference between naturally imposed parent material or artiﬁcially deposited substrates of an anthropogenic character can be observed (Schaetzl, 1998). Ipso facto, the presence of CLs allows the classiﬁcation of the soil proﬁle as lithological discontinuity soil (LDS). LDS is characterised by the appearance of contrast changes in texture classes throughout the solum or mineralogical composition of the individual horizons or layers from different ages (FAO, 2006; Lorz et al., 2010; Lorz and Phillips, 2006; Schaetzl,1998; Waroszewski et al., 2015). LDS constitutes a valuable source of information not only about the time scales of the soil formation itself (Lorz et al., 2010), but also about the direction of pedogenesis (Lorz, 2008; Lorz and Phillips, 2006; Schaetzl and Anderson, 2005; Waroszewski et al., 2016). The detailed criteria essential to determine lithological discontinuity (LD) within the soil proﬁle are speciﬁed in the World Reference Base for Soil Re- sources 2014 (IUSS Working Group WRB, 2015), where the thus far * This paper has been recommended for acceptance by Prof. W. Wen-Xiong. * Corresponding author. E-mail address: j.kowalska@ur.krakow.pl (J. Kowalska). Contents lists available at ScienceDirect Environmental Pollution journal homepage: www.elsevier.com/locate/envpol http://dx.doi.org/10.1016/j.envpol.2016.08.053 0269-7491/© 2016 Elsevier Ltd. All rights reserved. Environmental Pollution xxx (2016) 1e14 Please cite this article in press as: Kowalska, J., et al., Soil pollution indices conditioned by medieval metallurgical activity e A case study from Krakow (Poland), Environmental Pollution (2016), http://dx.doi.org/10.1016/j.envpol.2016.08.053