Iron and manganese migration in “soil–plant” system in Scots pine stands in conditions of contamination by the steel plant’s emissions

In this paper, Scots pine (Pinus sylvestris L.) roots grown in soils with and without contamination from emission of a plant steel were analyzed for Fe and Mn, as well as the shoots and needles with and lacking pollution. The aim was to assess the content of Fe and Mn in soils under given conditions, and the interaction between pine plant and soil in terms of metal accumulation in the fine roots, annual shoots, and annual needles. The iron content in the soil of polluted areas does not contrast with its control amount. Conversely, the iron content in fine pine roots under contamination conditions is 2.1-4.4 times higher than the control values. There were no significant excesses of the manganese content in the soil in polluted conditions compared to the control, but its content in the 0-20 cm soil layer is 27-32 times higher than the background concentrations. The iron contentment in belowground (fine roots) and aboveground (annual shoots and needles) parts of pine trees in a context of contamination is higher than the control values (2.1-4.4 and 1.50-1.54 times, respectively). The manganese content in fine pine roots under contamination conditions is 2.8-10.7 times less than in control, while its content in shoots and needles is higher (2.23-2.76 times) in comparison with the control. Based on the values of the biological accumulation and migration coefficients, what in each case slighter than one, for Scots pine the iron represent not an element that actively accumulates. Nevertheless, for manganese, this stock model is valid only for fine roots, whereas under the contaminated environment, the metal mobility steepen, and the migration pattern shifts towards increased manganese accumulation in the aboveground part of pine trees.