Epiphytic lichens of apple orchards in Poland, Slovakia, and Italy

Following the study of epiphytic lichens in 30 apple orchards from Poland, Slovakia and Italy the list of 74 taxa was prepared. The most common are the meso- to xerophytic and heliophilous species. The highest number of taxa was observed in Slovak orchards. Moreover, lichens shared with at least one other country were also noted mainly in Slovakia. Bark of apple trees seems to create favourable habitats for Bacidia rubella, which together with Strangospora pinicola were valuable founds in Polish orchards. In Slovak orchards, special attention should be paid to Acrocordia gemmata, Melanelixia glabra and Usnea hirta. Among interesting records in Italian orchards, Phaeophyscia hispidula and Ph. kairamoi can be mentioned

New lichen records from Bukovské vrchy Mts (NE Slovakia)

Interesting findings of 100 lichens from the Bukovské vrchy Mts (Biosphere Reserve Poloniny, Slovak part) are reported as the result of recent survey work. Two species are new for Slovakia: Fellhanera gyrophorica and Rinodina efflorescens, and 34 species are reported for the first time from the studied area. The new records for the country are shortly commented as well as ecological aspects of Agonimia repleta, Strigula stigmatella, Gyalecta ulmi and Belonia herculina

Does air pollution influence the success of species translocation? Trace elements, ultrastructure and photosynthetic performances in transplants of a threatened forest macrolichen

Species translocation can be considered as a primary conservation strategy with reference to in situ conservation. In the case of lichens, translocations often risk to fail due stress factors associated with unsuitable receptor sites. Considering the bioecological characteristics of lichens, air pollution is among the most limiting stress factors. In this study, the forest macrolichen Lobaria pulmonaria was used as a model to test the hypothesis that the translocation of sensitive lichens is effective only in unpolluted environments. At purpose, 500 fragments or whole thalli were translocated in selected beech forests of Central Europe (the Western Carpathians, Slovakia) where the species disappeared in the past and in oak forests of Southern Europe (Tuscany, Central Italy) where native populations are present. Prior to the translocation (May 2016) and after one year, morphological and ultrastructural features, trace elements as well as chlorophyll a fluorescence emission were analysed. Four years later, the effectiveness of lichen translocation was further evaluated as presence of the transplants and of newly formed individuals. After one year, the translocation ensured an effective survival of the thalli in remote oak and beech forests characterized by a negligible or low contamination by heavy metals. The transplants were considered successful and developed new lobules and rhizines, attaching by themselves to the bark of the host trees, looking overall healthy, without evident signs of alteration also at ultrastructural level. Moreover, in a few cases newly formed individuals were observed after four years. On the other hand, the results highlighted the link between the unsuccess of the translocation and air pollution in other areas of the Western Carpathians and suggested that current air quality still limits the possibility of recolonization in areas where the model species disappeared

Biological effects of airborne pollutants released during cement production assessed with lichens (SW Slovakia)

In this paper we investigated the biological effects of airborne pollutants released during cement production by means of epiphytic lichens (SW Slovakia). We assessed the effects of dust pollution on lichen diversity around a limestone quarry (on the quarry-facing and the opposite side of Fagus sylvatica boles) and the content of selected elements in samples of the lichen Xanthoria parietina collected around a cement mill, two quarries and urban and rural sites at increasing distance from the sources of pollution. Dust contamination from limestone quarrying affected lichen diversity within a distance of 350 m from the source. Approaching the quarry, the diffusion of basi-nitrophilous species, the decrease of acidophilous species and the asymmetrical distribution of lichens on the tree boles, with a higher coverage of basiphilous species in the side facing the source of dust were observed. These responses, based on the functional traits of the lichen diversity, are helpful in monitoring studies around similar sources of pollution. In samples of X. parietina collected around the quarries and the cement mill, Ca, Ti, Fe, V, Al and Ni were significantly higher than in the surrounding environment. Calcium was a good tracer for dust contamination around the quarries and the cement plant and a clear decrease in its content with increasing distance from the source was found, with normal values reached within 1700 m from the cement mill. Lichens can be successfully used as indicators to integrate instrumental monitoring networks, when air pollution from cement factories is concerned

Ecophysiological and ultrastructural effects of dust pollution in lichens exposed around a cement plant (SW Slovakia)

The study investigated the ecophysiological and ultrastructural effects of dust pollution from a cement industry in the lichen species Evernia prunastri and Xanthoria parietina, which were exposed for 30, 90 and 180 days around a cement mill, two quarries, and inhabited and agricultural sites in SW Slovakia. The results showed that dust deposition from quarrying activities and cement works at the cement mill (mainly enriched in Ca, Fe and Ti) significantly affected the photosynthetic apparatus of E. prunastri (sensitive to dust and habitat eutrophication), while X. parietina (tolerant to dust and habitat eutrophication) adapted to the new environment. The length of the exposure strongly affected the vitality of the mycobiont (measured as dehydrogenase activity) in transplanted lichens. Dust deposition led to ultrastructural alterations, including lipid droplets increase, swelling of cellular components, thylakoid degeneration and sometimes plasmolysis, which, on the whole, gave the cells an aged appearance. Photosynthetic parameters deserve further attention as potential indicators for monitoring early biological symptoms of the air pollution caused during cement production

Vitality of the cyanolichen Peltigera praetextata exposed around a cement plant (SW Slovakia): A comparison with green algal lichens

The suitability of the cyanolichen Peltigera praetextata (Sommerf.) Zopf as indicator of the effects of air pollution around a cement industry was investigated. For this purpose, lichen samples taken from an unpolluted site were exposed for 1-6 months at selected sites (a cement mill, two quarries, inhabited and agricultural sites) in SW Slovakia: physiological parameters and ultrastructural features were examined prior and after exposure. The responses of P. praetextata were then compared with those of the green-algal lichens Evernia prunastri and Xanthoria parietina co-located at the same sites. The performance of the cyanobacterial photobiont of P. praetextata (as reflected by the maximum quantum yield of primary photochemistry FV/FM and by the performance index PIABS) was negatively influenced mainly by the length of exposure in the urban and agricultural sites and less by dust pollution around the cement mill and the quarries. A significant increase in membrane lipid peroxidation products reflected the effects of oxidative stresses in all sites. The alteration of the content of water soluble proteins was detected in the samples exposed around the cement mill, while dehydrogenase activity did not show any significant pattern. Similarly to green algal lichens, ultrastructural alterations featured lipid droplets increase, swelling of cellular components, thylakoid degeneration and sometimes plasmolysis, which on the whole gave the cells an aged appearance, especially in the urban and agricultural sites. On the whole, E. prunastri confirmed to be the most sensitive to dust pollution, P. praetextata was likely influenced by microclimatic conditions and habitat eutrophication and X. parietina was the most resistant. When compared with green-algal lichens, P. praetextata was not the best indicator of the effects of cement dust pollution

Magnetic properties and element concentrations in lichens exposed to airborne pollutants released during cement production

The content of selected elements (Al, As, Ca, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, S, Ti, V and Zn) was measured in samples of the lichen Evernia prunastri exposed for 30, 90 and 180 days around a cement mill, limestone and basalt quarries and urban and agricultural areas in SW Slovakia. Lichens transplanted around the investigated quarries and the cement mill rapidly (30 days) reflected the deposition of dust-associated elements, namely Ca (at the cement mill and the limestone quarry) and Fe, Ti and V (around the cement mill and the basalt quarry), and their content remained significantly higher throughout the whole period (30–180 days) with respect to the surrounding environment. Airborne pollutants (such as S) progressively increased in the study area from 30 to 180 days. The magnetic properties of lichen transplants exposed for 180 days have been characterized and compared with those of native lichens (Xanthoria parietina) and neighbouring bark, soil and rock samples, in order to test the suitability of native and transplanted samples as air pollution magnetic biomonitors. The magnetic mineralogy was homogeneous in all samples, with the exception of the samples from the basalt quarry. The transplants showed excellent correlations between the saturation remanent magnetization (Mrs) and the content of Fe. Native samples had a similar magnetic signature, but the values of the concentration-dependent magnetic parameters were up to two orders of magnitude higher, reflecting higher concentrations of magnetic particles. The concentrations of As, Ca and Cr in lichens correlated with Mrs values after neglecting the samples from the basalt quarry, which showed distinct magnetic properties, suggesting the cement mill as a likely source. Conversely, Ti and Mn were mostly (but not exclusively) associated with dust from the basalt quarry. It is suggested that the natural geological characteristics of the substrate may strongly affect the magnetic properties of lichen thalli. Taking this into account, the results of this study point out the suitability of lichens as air pollution magnetic biomonitors