title: Temporal trends (1981-2007) of trace and rare earth elements in the lichen Cetraria islandica (L.) Ach. from Italian herbaria.
abstract: Twenty-four herbarium specimens of Cetraria islandica collected in Italy from 1981 to 2007 were used for retrospective analysis. Cd, Ce, Cu, Fe, Gd, La, Mn, Ni, Pb, Sb, V, Y, and Zn concentrations were measured. Pb showed a negative temporal trend, linked to the ban of leaded fuel for vehicles. Pb showed a negative correlation with the distance of the sampling sites from a highway in the years before 1995 and no relationship after that year, corresponding to the Pb content reduction in gasoline. A significant trend towards increasing Mn concentrations over time also emerged, which deserves further investigations due to Mn toxicity. Cluster analysis showed a group of elements of anthropogenic origin, while rare earth elements formed a separated cluster of natural origin. Lichens from herbaria proved to be a valuable tool for reconstructing historical trends in trace element deposition, highlighting variations produced by human activities.
authors.affiliation: Department of Pharmacy (DIFAR), University of Genova, Viale Cembrano 4, 16148 Genova, Italy. Electronic address: minganti@difar.unige.it.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Minganti
authors.affiliation: Department of Pharmacy (DIFAR), University of Genova, Viale Cembrano 4, 16148 Genova, Italy. Electronic address: drava@difar.unige.it.
authors.forename: Giuliana
authors.initials: G
authors.lastname: Drava
authors.affiliation: Department of Pharmacy (DIFAR), University of Genova, Viale Cembrano 4, 16148 Genova, Italy. Electronic address: depellegrini@difar.unige.it.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: De Pellegrini
authors.affiliation: Department of Earth Sciences, Environment and Life (DISTAV), Polo Botanico Hanbury, University of Genova, Corso Dogali 1M, 16126 Genova, Italy. Electronic address: pmod@unige.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Modenesi
authors.affiliation: Department of Earth Sciences, Environment and Life (DISTAV), Polo Botanico Hanbury, University of Genova, Corso Dogali 1M, 16126 Genova, Italy. Electronic address: malaspina@unige.it.
authors.forename: Paola
authors.initials: P
authors.lastname: Malaspina
authors.affiliation: Department of Earth Sciences, Environment and Life (DISTAV), Polo Botanico Hanbury, University of Genova, Corso Dogali 1M, 16126 Genova, Italy. Electronic address: giordani@dipteris.unige.it.
authors.forename: Paolo
authors.initials: P
authors.lastname: Giordani
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D004784:Environmental Monitoring; D007558:Italy; D008011:Lichens / Q000737:chemistry*; D008674:Metals, Rare Earth / Q000032:analysis*; D062211:Spatio-Temporal Analysis; D014131:Trace Elements / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D008674:Metals, Rare Earth; D014131:Trace Elements
keywords: Cetraria islandica; Herbaria; Lichen; Temporal trend; Trace element