The influence of Cracow urban pollution on small forest areas

The impact of Cracow conurbation on small forest ecosystems was studied during the last four years (1998-2001). Seven sites located at different distances from the city and from busy road were selected. Lichen Hypogymnia physodes from unpolluted areas were transplanted to each of investigated sites for 6-month period (winter 1998/1999, 1999/2000, summer 2000). The quantity of litter fall with percentage composition of each species was estimated, also the input of litter and heavy metals to the forest floor were evaluated. Metal concentration (Cd, Ph, Cu, Zn, Fe) in Hypogymnia physodes, leaves of common oak, hornbeam and litter fall were determined in IL 251 flame AAS. Acute injuries of lichen thalli as well as concentrations of Pb, Zn, Fe and S were higher after winter transplantation and in sites located close to Cracow conurbation. High concentration of heavy metals were noticed in tree leaves from eastern transect as the effect of steel works emission as well as in those sites from southern transect situated nearby the city, Although air pollution has generally declined in the Malopolska district over the last few years the metal concentration and input to the forest floor in 2001 remains at the same level than in the previous years.