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To investigate the suitability of three lichen species (Cetraria islandica, Evernia prunastri, and Ramalina farinacea) as transplants to trace-element air biomonitoring, they were exposed on substratum-free supports, from July 1996 until July 1997, in three European countries with different climates (Germany, Italy, Romania), at six sites with different types of air pollutants (two in each country). After 2, 4, 6, and 12 months of exposure, some portions of thallus were collected, prepared, and measured by instrumental neutron activation analysis (INAA) at the Institute of Physics and Nuclear Engineering in Bucharest and by energy dispersive X-ray fluorescence analysis (EDXRFA) at the University of Hohenheim in Stuttgart. Fifteen environmentally relevant elements: As, Br, Ca, Co, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Sb, V, and Zn were determined. The analytical results were compared statistically. To study the distribution of the trace-elements between the lichens and the lichen throughfall water inside a virtual column, the throughfall water was collected under the lichen transplants during 6 and 12 months. The dried residues were analysed by INAA at Bucharest. The accumulating capacity for all investigated species is evident. For a comparative evaluation, the initial element contents, the "accumulation factors" relative to the bulk deposition, the interspecies "calibration factors", and the "retention efficiencies", defined as ratios of the lichen enrichment to the sum of this enrichment and the content in the lichen throughfall water, were considered. These criteria attest the best suitability for Evernia prunastri, followed by Ramalina farinacea and Cetraria islandica.

Samples of Evernia prunastri, collected in a mountainous zone, were exposed in urban and highly industrialized areas in order to monitor the atmospheric pollution. Amounts of Cr, Mn, Fe, Ni, Cu, Zn, and Pb were determined by EDXRF spectrometry in secondary target excitation mode and in the thin film approach. An increase in metal concentrations was noted on all sites with time exposition increases, but the highest final amounts were observed on those thalli mounted near a steel works. The washing procedure influenced the concentration of all the elements as previously verified on Pseudevernia furfuracea.

A synthesis of the epiphytic lichen vegetation on larch in the Italian Alps is presented. Vegetation types are described on the basis of a numerical classification of 291 relevés. They can be compared to a few well-known phytosociological unions found in other parts of the Alps. Some communities are restricted to subalpine areas with continental climate. Despite the homogeneity of the substrate, the flora is rich, with 98 species, several of which are rare, and hence of interest from a conservational point of view. [ABSTRACT FROM AUTHOR]

The distribution of the epiphytic macrolichen Lobaria pulmonaria (L.) Hoffm. was surveyed in the Regional Forest of Cansiglio, extending over 3,500 ha in the eastern part of the Veneto Pre-Alps (north-east Italy). Data on the main characteristics of the forest sites and on Lobaria trees were collected with the aim to evaluate the main ecological factors, related to forest composition and management, affecting the distribution of Lobaria pulmonaria . Lichen diversity was surveyed on 15 randomly selected Lobaria trees. A good correlation between macrolichens and the total number of species was found. The largest Lobaria populations are concentred in the north-eastern part of the forest, where mixed and multi-plane silver fir – beech formations prevail, and selective cutting is carried out. Our data has enabled us to develop some criteria for the identification of priority conservation sites for Lobaria pulmonaria and lichen diversity in the study area, improving the focus on biodiversity in the management of the forest. [ABSTRACT FROM AUTHOR]