Biomonitoring is used to study the performance of a single air sampler as representing air elemental concentrations in Lisbon. A database of chemical elements' concentrations was obtained by analysing exposed lichens and bark, hung on courtyard trees of 22 Lisbon basic schools from January to May 2008 and June to October 2008 (winter and summer campaigns). Electric conductivity was also measured in lichens, as a sensitive indicator of lichen vitality and, indirectly, of air pollution. This work also enabled evaluation of stress effects in lichens as a result of transplanting from unpolluted to air–polluted areas, the adaptation of transplanted biomonitors into new meteorological and physical–chemical conditions, and the comparison of performance of both biomonitors.
Keywords: biomonitors, bark, lichen, neutron activation, chemical elements, spatial distribution, environmental pollution, air pollution, spatial mapping, Lisbon, Portugal, biomonitoring