The mobilisation of selenium into the biosphere by human activity has become an important process in the geochemical cycling of this element. This study reports the Se content in elemental, exchangeable and organic-bound forms by conducting sequential extraction of soil and evaluation of selenium behaviour in soils developed from loess. The evaluation of Se immobilisation and mobilisation factors in soils included the role of soil in areas with diverse land use and high anthropogenic pressure. Lublin, where the study was conducted, was divided into 5 areas according to the land use pattern. i.e.: industrial areas (IA), areas used by transport (TA), housing estates (HA), municipal gardens (GA), farmland (FA), municipal forest (FC) and two benchmark profiles: arable farmland area (FAR), and forest area (FCR) in Czesławice n. Nałęczów, that is outside of the Lublin agglomeration impact zone. The results of Se fractionation in soil indicated that industrial pollution (IA) and heavy fertilisation and pesticide use (GA) exert an impact on the mobilisation and transformation of most of this element in the environment. The mean Se total content in urban soil is in the range 0.81 - 0.397 mg kg-1. The distribution of Se concentrations in soil profiles demonstrated a tendency towards Se attaining the highest values in the topsoil, while decreasing with depth. Exchangeable and oxidised organic-bound forms correlate with the organic and mineral content of 1-0.1 mm fraction. No correlation between the selected Se forms and the soil’s silt fraction was observed; in contrast, a negative correlation was noted with the fine clay fraction.

22.4.2017