title: Infraspecific variability in baseline element composition of the epiphytic lichen Pseudevernia furfuracea in remote areas: implications for biomonitoring of air pollution.
abstract: The epiphytic lichen Pseudevernia furfuracea is widely used as biomonitor of airborne trace elements and other contaminants and consists of two taxonomic varieties (var. furfuracea and var. ceratea). Here, we assessed the occurrence of inter-varietal differences in the elemental composition of paired samples of var. furfuracea and var. ceratea collected in 20 remote sites of Italian mountains. The concentration of 40 elements was measured by inductively coupled plasma mass spectroscopy, after digestion with HNO3and aqua regia. The magnitude of inter-varietal differences compared to the effect of large-scale site-dependent environmental factors (i.e., lithological substrate, host tree species, and altitude) on overall element content was explored by multivariate analysis techniques and tested by generalized linear mixed modeling (GLMM). Further GLMMs were separately fitted for each element testing taxonomic-related variability against uncertainty associated to the analytical procedure. Inter-varietal differences were statistically significant only for Hg and P, with higher content in var. ceratea at most sites, and for Mg and Zn, showing the opposite pattern. Since the elemental composition of P. furfuracea in remote sites was mostly affected by local lithology and climatic conditions, our results confirm that lichen material for active biomonitoring should be collected in a single ecologically homogeneous remote area. We also indicate sites in the Eastern Alps where P. furfuracea showed the minimum content of most elements, which are suggested as locations to collect lichen material for transplants. Besides the context-dependency at large spatial scale, variations of elemental composition apparently related to taxonomy, could possibly be due to unequal incidence of morphological traits of the collected material. Further research is needed to clarify this issue, and how it affects bioaccumulation phenomena.
authors.affiliation: Department of Agri-Food, Animal and Environmental Sciences (DI4A), University of Udine, Udine, Italy.
authors.forename: Guido
authors.initials: G
authors.lastname: Incerti
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Elva
authors.initials: E
authors.lastname: Cecconi
authors.affiliation: Department of Biology, University of Naples Federico II, Naples, Italy.
authors.forename: Fiore
authors.initials: F
authors.lastname: Capozzi
authors.affiliation: Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Adamo
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Bargagli
authors.affiliation: Department of Biology, University of Florence, Florence, Italy.
authors.forename: Renato
authors.initials: R
authors.lastname: Benesperi
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy.
authors.forename: Fabio Candotto
authors.initials: FC
authors.lastname: Carniel
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach (FEM), San Michele all'Adige, Italy.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Cristofolini
authors.affiliation: Department of Biology, University of Naples Federico II, Naples, Italy.
authors.forename: Simonetta
authors.initials: S
authors.lastname: Giordano
authors.affiliation: Natural History Museum and Botanical Garden, University of Calabria, Calabria, Italy.
authors.forename: Domenico
authors.initials: D
authors.lastname: Puntillo
authors.affiliation: Department of Biology, University of Naples Federico II, Naples, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Spagnuolo
authors.affiliation: Department of Life Sciences, University of Trieste, Trieste, Italy. tretiach@units.it.
authors.forename: Mauro
authors.identifier: http://orcid.org/0000-0002-0529-1359
authors.initials: M
authors.lastname: Tretiach
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000032:analysis; D001203:Ascomycota / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods; D007558:Italy; D008011:Lichens / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D014131:Trace Elements / Q000032:analysis
chemical_list: D000393:Air Pollutants; D019216:Metals, Heavy; D014131:Trace Elements; D010758:Phosphorus
keywords: Atmospheric depositions; Baseline values; Lichen transplants; Taxonomy; Trace elements; ceratea; furfuracea