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The geochemistry and mineralogy of urban soils are influenced by various superimposing anthropogenic and geogenic factors.Urban development starts on natural soils originally reflecting the geogenic geochemical and mineralogical background.During urban development urban soils are locally affected by the specific land use types and spatially affected by diffuse pollution.This diffuse pollution is often caused by the deposition of atmospheric particles and results in urban wide soil pollution without showing distinct borders.Due to the fact that urban soils often have neutral pH values,especially heavy metals tend to be accumulated over the time.Typical sources of diffuse pollution are traffic,industry and domestic heating.However,also other sources such as extended construction activities or waste disposal can contribute to soil pollution over extended areas.Furthermore,urban land use does not only alter the geochemical patterns of soils but also their mineralogical patterns.Thus,for a comprehensive understanding of the geochemistry and mineralogy of urban soils,it is important to discriminate these superimposing soil polluting factors.Geostatistics provide the possibility to model the urban wide diffuse soil pollution.Studies in various cities (Karlsruhe,Pforzheim,Qingdao) have shown that urban surface soils are continuously contaminated over extended areas overprinting geochemical and mineralogical signals from the natural background.Cross validation can be used to identify soils whose geochemical patterns do not fit into the overall trend.Those soils can be,for example,locally polluted,transported or artificial.In regard to Karlsruhe,it could be demonstrated that the intersection of spatial distributions of pH values and Zn concentrations identifies areas where herbaceous vegetation also show elevated Zn concentrations.Factor analysis in combination with interpolation methods such as geostatistics is able to differentiate the spatial distribution of contaminants from different sources,parent materials and weathering processes as was demonstrated in a study combining mineralogical and geochemical parameters of urban surface soils from Pforzheim,Germany.In this study,four factors could be extracted,which reflect diffuse pollution,parent material,residual phases and weathering products.The respective factor scores were calculated for each soil sampling site and interpolated.Enrichments of phyllosilicates,carbonates,Fe-concentrations and elevated pH-values were identified in inner urban soils over sandstone in relation to forest soils over sandstone.Consequently,the adsorption capacitiy for heavy metals will be higher in inner urban soils of Pforzheim overlying sandstone as in the neighboring forest soils.Furthermore,urban soils can be classified by cluster analysis asshown for Karlsruhe.The cluster centers obtained from clustering the sampling sites (q-mode cluster) reflect the patterns obtained from clustering a large set of geochemical variables (r-mode cluster).This method primarily discriminated clusters of soil sampling sites according to the dominating geogenic background and to intensive local contaminations.On a subcluster level,signals of the diffuse pollution were identified.The presented methods enable to assess the ongoing diffuse pollution of urban soils,which is certainly a task that has to be included into future sustainable urban development.