Elemental distribution in lichens transplanted to polluted forest sites near Kraków (Poland)

This study describes elemental distribution in the epiphytic lichen Hypogymnia physodes (L.) Nyl., with emphasis on heavy metals. Micro-PIXE measurements were performed using the nuclear microprobe at the iThemba LABS, South Africa. Detailed information from different thallus layers was obtained by performing true elemental mapping using the dynamic analysis method, complemented by analyses of selected smaller areas and point analyses. Cl and K concentrations were high near the algal layer whilst S concentrated mostly in the algal and lower cortex layers. The highest concentrations of P were found in the lower cortex. Mn and Zn were mostly concentrated in the algal layer and lower cortex while high concentrations of Fe were noted in the lower cortex. The highest concentrations of Ca and Pb were found in the medullary layer. Mapping of lichen samples soaked in Pb(NO ₃) ₂ solution proved that the highest Pb concentration occurred in the upper and lower cortex.