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Magnetic properties of soils have been recently profitably used in examining industrial pollution.Topsoil layers act as sink of atmospherically deposited dust,which usually comprises,among others,high portion (5-10 wt %) of ferrimagnetic Fe-oxides.Beside combustion of fossil fuel,other sources,as iron and steel works,public boilers and road traffic contribute to soil contamination by anthropogenic ferrimagnetics.Low-field magnetic susceptibility represents one of the major magnetic parameters,indicating concentration of ferrimagnetic particles in soils.Therefore,relative simple and fast in situ mapping of topsoil magnetic susceptibility can be used as a proxy to determine the spatial distribution of environmental pollution.However,since topsoils may in general contain complex population of magnetic minerals of different origin,knowledge on vertical distribution of anthropogenic ferrimagnets is of crucial importance.Previous large-scale surface mapping of magnetic susceptibility of forest soils in Czech Republic revealed anomaly in Northern Moravia.This area is eharacterised by high concentration of industrial centres,producing environmental stress due to high level of emissions.The aim of this study is detailed magnetic analysis of contaminated soils around an industrial city of T(r)inec.We investigated topsoil magnetic susceptibility,as well as other magnetic parameters along vertical soil profiles with the aim to assess lithogenic,pedogenic and anthropogenic contributions and to establish criteria for routine monitoring of soil contamination in this region.Vertical distribution of magnetic susceptibility down to about 30 cm show typical features-extremely enhanced values in the uppermost layer and very low and practically constant values in deeper horizons.Topsoil values of magnetic susceptibility,measured on the soil surface,are the highest in close neighbourhood of the industrial town of T(r)inec,and decrease with increasing distance.Significant correlation between topsoil magnetic susceptibility and concentrations of Fe,Pb and Zn.Regarding the subsoil horizons,magnetic susceptibility is about 10-40 times lower than the maximum values of topsoil horizon.Moreover,very low and stable values in depths below some 8 cm unambiguously confirm negligible contribution of ferrimagnetics of lithogenic origin.In the case of samples from the magnetically enhanced topsoil horizon,frequency dependent magnetic susceptibility (κ fd) values were around 1% which reflects absence of superparamagnetic pedogenic magnetite in the enhanced topsoil layer.Magnetic analysis of vertical soil profiles showed that elevated values of surface-soil magnetic susceptibility is solely due to atmospherically deposited magnetite particles of anthropogenic origin,which concentrated in the top 5-(~)7 cm.The effect of geological background and pedogenic processes to concentration of ferromagnetic particles in these soil horizons is negligible.Coarse-grained magnetite seems to be the prevailing magnetic phase in topsoils,while it is missing in deeper layers.Therefore,fast in-situ measurements of surface-soil magnetic susceptibility can be used in this region for reliable assessment and monitoring of degree of soil contamination by atmospherically deposited particulate matter and selected associated heavy metals.This study was supported by Grant Agency of the Czech Republic through grant No.205/07/0941.