Accumulation of heavy metals by ectomycorrhizal fungi colonizing birch trees growing in an industrial desert soil

The results of analyses conducted to determine contents of Cd(II) and Pb(II) in mushrooms of mycorrhizal fungi and selected parts of birches growing in an industrial desert surrounding a nonferrous works are presented in this study. The fruiting bodies of fungi accumulated several times higher contents (up to 80 mug g(-1) dry weight) of Cd(II) compared to those found in the soil (20 mug g(-1) dry weight). In contrast, the mushroom contents of Pb(II) were only slightly increased (up to 895 mug g(-1) dry weight) than those present in the soil (500 mug g(-1) dry weight). However, fivefold higher concentrations of the metals were found in the mycorrhizal roots. Comparing the distribution of the metals analysed, the protective role of the ectomycorrhizae in relation to the host tree was indicated. Mycorrhizal fungi persistently fixed heavy metals, forming an efficient biological barrier that reduced movement of the metals in birch tissues.