Air quality changes witnessed by herbarium specimens of lichens: a case-study in the Western Carpathians
(1) Department of Biology, University of Pisa, Pisa, Italy (2) Plant Science and Biodiversity Centre, Slovak Academy of Sciences, Bratislava, Slovakia
Lichen collections may contribute to a better understanding of past environmental conditions. Concentrations of heavy metals and metalloids, i.e. Al, As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, S, Sb, and Zn were measured in thalli of the lichen Lobaria pulmonaria Hoffm. from remote mountain areas of the Western Carpathians, Slovakia. Old collections as well as recently collected material were selected for a retrospective analysis: in particular twenty specimens covering the period 1960 - 2022. Lobaria pulmonaria was selected as a model, being strictly associated to remote areas with high environmental quality in the Western Carpathians. The species has suffered a general decline throughout Europe as a consequence of air pollution and intensive forest management. Nowadays, it is widely acknowledged as a model of "umbrella" species, i.e., an indicator of important forest habitat for the conservation of rare species and understudied groups (e.g. bryophytes). Currently, it is threatened and red-listed in several European countries, mainly in Central Europe, where it is also protected by law. This study allows to detect air quality changes in remote areas and the decline of air pollution from heavy metals with reference to the investigated period, as well as characterization of past and current background concentrations for selected heavy metals in the Western Carpathians. Besides a reconstruction of air pollution history, the potential of lichen collections from remote areas combined with freshly collected material to define past background of element concentrations as well as their changes is raised.
Keywords: Bioaccumulation, Biomonitoring, Heavy metals, Herbarium specimens, Remote areas
