Epiphytic Lichen Communities Research Articles

Initial stages of recovery of epiphytic lichen communities after reduction of emissions from a copper smelter

Analysis has been made of changes in the species composition and abundance of epiphytic lichens on fir trees during the first decade after a sharp reduction of emissions from a large copper smelter in the Middle Urals. The results show that lichens have recolonized the area of the former lichen desert and that the abundance of lichen species in the impact and buffer zones has increased. However, a fairly long time is required before lichen communities in the vicinity of the smelter can recover to the background state, since species highly sensitive to pollution still occur only in the background area.

Small, fragmented native oak forests have better preserved epiphytic lichen communities than tree plantations in a temperate sub-oceanic Mediterranean climate region

Abstract In increasingly fragmented landscapes tree plantations are thought to help maintain forest continuity among native patches. Epiphytic lichens are one of the most sensitive groups to change in forest conditions, but the effects of this management practice are still poorly studied in temperate regions. In this study we compared epiphytic lichen diversity among small patches of old, native oaks (Quercus pyrenaica) and young, planted chestnuts (Castanea sativa) and Monterey pines (Pinus radiata) in a major forestry area in northwestern Spain. Our results showed that the richness of epiphytic lichens was higher in C. sativa than Q. pyrenaica, but that the latter had more lichen species typical of mature forests, including macrocyanolichens. Overall, C. sativa plantations had more species typical of well-lit, dry environments than Q. pyrenaica or P. radiata, which is likely caused by the natural architecture of each tree species, and to differences in forest age and management. At the tree level, Q. py...

Epiphytic Lichen Diversity as Indicator of Environmental Quality in an Industrial Area (Central Lithuania)

ABSTRACT The objective of the study was to evaluate the impact of nitrogen fertilizer industry pollution on epiphytic lichen communities. The study plots are located in Scots pine Pinus sylvestris stands at different distances (up to 12 km) to the northeast and southwest of the nitrogen fertilizer producer plant in central Lithuania. The stands were semi-mature and mature and growing on sandy sites of the Vaccinio-myrtillosa site type. Species richness, composition and index of atmospheric purity (IAP) were assessed at each site. Species diversity was calculated by grouping species by their ecological values for eutrophication. Species frequency was calculated according to lichen life strategies (growth forms, photobionts, reproductive strategies). Twenty lichens species were recorded in the surrounding of the pollution source. An increase in species richness and diversity was found with increasing the distance up to 10 km from the plant. Based on IAP values three zones ( 10 km) with different...

Patterns and drivers of lichen species composition in a NW-European lowland deciduous woodland complex

We surveyed lichens in an extensive area of lowland deciduous oak and beech dominated forest under wood pasture management within the New Forest National Park, southern England. This provided the basis for an investigation of factors affecting the species density and composition of epiphytic lichen communities. Fifteen 1 hectare plots were established in the same sites as a parallel invertebrate survey, of which nine were in old growth forest and six in oak plantations of between c. 150 and 300 years old. In each plot 12 trees were identified for sampling and lichens were sampled on four aspects of each trunk. Results at the plot level showed that species density was significantly higher in the old growth woodland plots from those in plantations. Plot age had a significant effect on species on oak but this was not significant for lichen communities on beech. The species density of lichens associated with Trentepohliaceae photobionts on oaks showed a linear positive relationship with increasing plot age while the species density of species with other coccal green Chlorophyta decreased with age of the plot. A major part of the lichenised fungi with Trentepohliaceae photobionts includes indicator and notable species used in conservation evaluation and this component is most affected by fragmentation and isolation of forest sites. The results emphasise the importance of long term connectivity and ecological continuity in this extensive mosaic of lowland deciduous forest.

Do tree-related factors mediate the response of lichen functional groups to eutrophication?

In the last decades, the pollution regime has been drastically changed in most industrialized countries, with a considerable decrease in sulphur dioxide (SO2) emissions and an increasing relevance of eutrophication compounds, such as nitrogen compounds and particulate matter. This situation hampers the interpretation of data in biomonitoring surveys, as high lichen diversity is not always associated with good air quality. The objective of this study was to test whether the effects of eutrophication on the abundance of different lichen functional groups varies according to some tree-related factors. We analysed the relationships between epiphytic lichen diversity, emissions of main atmospheric pollutants and tree characteristics (circumference and bark pH, light transmitted through the canopy). Hierarchical partitioning of variance and Generalized Linear Mixed Models (GLMM) confirmed that lichen functional groups with different nitrogen tolerances responded to several atmospheric pollutants, with both independent and joint effects, whereas they did not show significant differences depending on main tree-related factors. We demonstrated that, under high eutrophication levels, differences in bark pH did not significantly differentiated the composition of epiphytic lichen communities.

Epiphytic Communities of Open Habitats in the Western Tian-Shan Mts (Middle Asia: Kyrgyzstan)

The paper presents the results of bryosociological research conducted on the epiphytic vegetation in the western Tian-Shan Mountains in 2013. The surveys on epiphytic bryophyte and lichen communities were done on 115 sites with different quantity of trees (solitary, in alleys or wood plots along river valleys) distributed in several mountain ranges within study area. In total 21 epiphytic moss species were found during research which composes characteristic species combinations making apparent difference between associations. As a result of field research and numerical analyses, three separate groups of samples corresponding to seven associations and one community within three alliances: Ulotion crispae and Syntrichion laevipilae (Frullanio dilatatae-Leucodontetea sciuroidis class) as well as Neckerion complanatae (Neckeretea complanatae class) have been distinguished. A synopsis of the epiphytic moss communities is proposed. The most interesting is the association of Orthotrichetum crenulati which is described here for the first time. Two species of epiphytic mosses (Orthotrichum crenulatum and O. pallens) are new to Kyrgyzstan.

A Pine Is a Pine and a Spruce Is a Spruce--The Effect of Tree Species and Stand Age on Epiphytic Lichen Communities.

With an increasing demand for forest-based products, there is a growing interest in introducing fast-growing non-native tree species in forest management. Such introductions often have unknown consequences for native forest biodiversity. In this study, we examine epiphytic lichen species richness and species composition on the trunks of non-native Pinus contorta and compare these to the native Pinus sylvestris and Picea abies in managed boreal forests in northern Sweden across a chronosequence of age classes. Overall, we recorded a total of 66,209 lichen occurrences belonging to 57 species in the 96 studied forest stands. We found no difference in species richness of lichens between stands of P. contorta and P. sylvestris, but stands of P. abies had higher total species richness. However, species richness of lichens in stands of P. abies decreased with increasing stand age, while no such age effect was detected for P. contorta and P. sylvestris. Lichen species composition progressively diverged with increasing stand age, and in 30-year-old stands all three tree species showed species-specific assemblages. Epiphytic lichen assemblages in stands of 30-year-old P. contorta were influenced by greater basal area, canopy closure, and average diameter at breast height, P. abies stands by higher branch density and canopy closure, and stands of P. sylvestris by greater bark crevice depth. Differences in lichen species richness and composition were mainly explained by canopy closure and habitat availability, and the greater canopy closure in mature P. abies stands promoted the colonization and growth of calicioid lichen species. Our results indicate that the non-native P. contorta have similar species richness as the native P. sylvestris. The main difference in lichen species richness and composition is between P. abies and Pinus spp. in managed forests of boreal Sweden.

State of epiphytic lichen communities under anthropogenic impact: Effect of abundance assessment methods on the informativity of indices

A comparative analysis has been performed on the informativity of characteristics of the state of lichen cover calculated by two methods for evaluating lichen abundance (frequency and projective cover). A close correlation of the indices obtained by the two different methods was shown, as well as their significant association with the degree of stress, which confirms their equal usefulness in lichenoindication works. However, comparison of the informativity established that the indices based on frequency have higher resolution capability.

Lichen Monitoring Delineates Biodiversity on a Great Barrier Reef Coral Cay

Coral islands around the world are threatened by changing climates. Rising seas, drought, and increased tropical storms are already impacting island ecosystems. We aim to better understand lichen community ecology of coral island forests. We used an epiphytic lichen community survey to gauge Pisonia (Pisonia grandis R.BR.), which dominates forest conditions on Heron Island, Australia. Nine survey plots were sampled for lichen species presence and abundance, all tree diameters and species, GPS location, distance to forest-beach edge, and dominant forest type. Results found only six unique lichens and two lichen associates. A Multi-Response Permutation Procedures (MRPP) test found statistically distinct lichen communities among forest types. The greatest group differences were between interior Pisonia and perimeter forest types. Ordinations were performed to further understand causes for distinctions in lichen communities. Significant explanatory gradients were distance to forest edge, tree density (shading), and Pisonia basal area. Each of these variables was negatively correlated with lichen diversity and abundance, suggesting that interior, successionally advanced, Pisonia forests support fewer lichens. Island edge and presumably younger forests—often those with greater tree diversity and sunlight penetration—supported the highest lichen diversity. Heron Island’s Pisonia-dominated forests support low lichen diversity which mirrors overall biodiversity patterns. Lichen biomonitoring may provide a valuable indicator for assessing island ecosystems for conservation purposes regionally.

Contrasting responses of epiphytic and terricolous lichens to variations in forest characteristics in northern boreal ecosystems

The main environmental factors that drive lichen communities are still poorly known in northern boreal ecosystems. This study compares the effects of forest stand characteristics (height, canopy cover, and age) on fruticose epiphytic and terricolous lichen communities across a large region located at the interface between closed-crown boreal forests and northern open woodlands in the province of Quebec (Canada). The dataset consists of 875 plots spread across a 242 000 km2 territory that ranges from the eastern to the western extremities of the province. The biomass of fruticose epiphytic lichens (Alectoria, Bryoria, Evernia, and Usnea) was evaluated at the branch, tree, and plot levels, and terricolous lichen cover (Cladonia spp.) was evaluated at the plot level. The results indicate that epiphytic and terricolous lichens respond significantly but differently to variations in forest characteristics. At the plot level, epiphytic lichen biomass was highest in the oldest stands (>100 years) and lowest in stand with low canopy cover (<25%) or in stands dominated by relatively short trees (<7 m). By contrast, terricolous lichen cover was highest in stands dominated by short (<7 m) or mid-sized (7–12 m) trees and lowest in stands with a relatively high canopy cover (>40%) or stands of intermediate age (60 to 100 years old). Species composition of epiphytic communities was also examined, and some species or genera exhibit a strong association with older stands (Alectoria sarmentosa (Ach.) Ach., Bryoria spp.) or with specific regions along the ca. 1500 km east–west gradient (Evernia mesomorpha Nyl. in the western part, Bryoria spp. in the central part, and A. sarmentosa in the eastern part). In terms of conservation, these results indicate that epiphytic lichens communities are potentially sensitive to the preferential logging of older stands. Both epiphytic and terricolous lichen communities are also potentially sensitive to expected climate change effects such as increased fire frequencies or increased forest growth.

Patterns of β-diversity and similarity reveal biotic homogenization of epiphytic lichen communities associated with the spread of black locust forests

We compared epiphytic lichen communities of native broadleaved and secondary black locust (Robinia pseudoacacia) forests to detect possible differences in community structure that could be indicative of biological homogenization enhanced by the replacement of native by black locust forests. The study was carried out in two areas of Italy with different bioclimatic conditions using a balanced stratified random sampling. Results reveal a different pattern of community structure between native and black locust forests across the two regions that may reflect a process of biological homogenization. In particular, lichen communities of black locust forests share several species between the two study regions. This pattern of floristic homogenization parallels with a functional homogenization related to the spread of highly competitive species. This research provides early evidence that the decrease of native forests associated with the spread of black locust is a mechanism triggering biological homogenization of the epiphytic lichen biota.

Epiphytic lichen conservation in the Italian Alps: the role of forest type

Epiphytic lichens are a functionally important and species-rich component of Alpine forests, including several species of conservation concern. Their dependence on specific host trees predicts that forests with different tree species composition host different lichen communities, enhancing lichen diversity in forest landscapes. In this study, we tested for the first time the effect of forest type on patterns of epiphytic lichen diversity, in the Italian Alps. We sampled the main forest types of the South Tyrol, a typical Alpine region of Italy. We also assessed the influence of factors related to forest structure and climatic conditions. Our results demonstrate that different forest types host statistically different lichen communities, suggesting that the conservation of lichen diversity is entrusted to the maintenance of forest landscape heterogeneity, including forest types of minor economic value and rural habitats. The highest number of species was found in grazed larch forests and in high-elevation spruce forests, while the poorest pool was found in low-elevation spruce forests, beech forests and Scots pine ( Pinus sylvestris ) forests. High-elevation spruce forests also had the highest number of red-listed lichens, as the non-intensive management of these forest type allows the establishment of a rich lichen biota. Our results also emphasize the role for lichen conservation of some forest types that are of minor economic importance, such as oak ( Quercus pubescens ), riparian, and silver-fir ( Abies alba ) forests. This can also apply to grazed larch ( Larix decidua ) forests that are maintained by traditional farming, which shape one of the most pleasing aspects of the Italian Alpine landscapes. • Does forest type predict epiphytic lichen diversity in the Italian Alps? • We studied epiphytic lichen communities in the main forest types of the Italian Alps. • Significant differences in species composition and richness were found among forest types. • Conservation of lichen diversity is linked to the maintenance of forest landscape heterogeneity. • Forest with low-economic value highlighted also a key role on lichen conservation.

Biological effects of ammonia released from a composting plant assessed with lichens

In this study, we investigated whether ammonia emissions from industrial composting of organic waste may influence the surrounding environment, using lichens as bioindicators. To this purpose, samples of N-tolerant and N-sensitive lichens, namely Xanthoria parietina and Evernia prunastri, were transplanted for 1-3months along transects at increasing distance (0-400m) from a composting facility in Tuscany, Italy. Atmospheric concentrations of ammonia were measured using passive samplers. The physiological response of lichen transplants was investigated by means of the photosynthetic efficiency (measured as chlorophyll a fluorescence emission), the integrity of cell membranes (measured as electrolyte leakage), and sample viability (measured as enzymatic activity of dehydrogenase). Epiphytic lichen communities were investigated using biodiversity indices. The results showed decreasing concentrations of ammonia, from 48.7μg/m(3) at the composting facility to 2.7μg/m(3) at 400m. The N-tolerant X. parietina was not affected and some physiological parameters even showed a higher performance, while the N-sensitive E. prunastri showed a reduced performance with increasing atmospheric concentrations approaching the source. A shift from lichen communities composed by meso-acidophilous species (actual condition) to more nitrophilous communities in the near future, approaching the composting facility is suggested. It is concluded that lichens can provide useful data for decision-makers to establish correct science-based environmentally sustainable waste management policies.

Mediterranean old-growth forests: the role of forest type in the conservation of epiphytic lichens

The present study investigated the effect of forest type on epiphytic lichen communities and selected indicator species, useful for long-term monitoring programs in Mediterranean forests. The results showed that only few species are common to many plots while others are locally rare. Epiphytic lichen diversity and communities were significantly influenced by forest type: Quercus cerris-dominated forests hosted a richer lichen flora, Fagus sylvatica-dominated forests showed the majority of rare species, while mixed forests, though poorly represented in the study area, hosted the majority of indicator species, revealing the presence of important and exclusive habitats. In particular, old established forests are characterized by both standand treecontinuity, while mixed forests offer a higher diversity of tree substrates. Our findings highlight the role of tree substrate variability for lichen colonisation. The presence of non-dominant tree species contributes to the variability of habitats and ecological niches. This allows the development of well preserved lichen communities compared to those of structurally less complex or even monospecific forests.

Epiphytic lichens in jack pine and black spruce plantations in northern Ontario, Canada: diversity and community patterns

This study was an investigation of epiphytic lichen communities in mid-rotation (45 to 55 years old) managed stands of jack pine (Pinus banksiana) and black spruce (Picea mariana) in northern Ontario. Lichen community structure was compared between pine and spruce stands, and relationships between community structure and environment (substrate, microclimate, and stand-level parameters) were explored. We also assessed habitat associations of lichens with differing growth forms and functional traits. Nonmetric multidimensional scaling was used to analyze community structure, and results showed that differences between pine and spruce stands were most strongly related to stand basal area and light levels, but were also associated with other factors such as branch diameter. In addition, distinct differences in occurrence patterns between functional groups were observed, with fruticose lichens more common in pine stands, and asexual foliose lichens more common in spruce stands. This study represents the first detailed examination of epiphytic lichen community composition in boreal plantation forests in North America. Our results suggest that the conifer species chosen to regenerate a harvested stand will influence epiphytic lichen communities, which may have further implications for ecosystem processes such as nutrient cycling, and for wildlife species dependent on lichens, such as woodland caribou (Rangifer tarandus caribou).

Patterns in the occupancy and abundance of the globally rare lichen Erioderma pedicellatum in Denali National Park and Preserve, Alaska

We investigated habitat attributes related to the occupancy of the globally rare and endangered epiphytic lichen, Erioderma pedicellatum, in a newly discovered (2009) population center in Denali National Park and Preserve (DNPP), Alaska. We measured forest, tree and epiphytic lichen community characteristics on eighty-five systematically selected plots in four study areas. We aggregated these data at three spatial scales (tree, plot and study area) at which to compare E. pedicellatum occupancy (probability of occurrence) and abundance to environmental covariates. We observed 2,035 E. pedicellatum thalli on 278 individual Picea glauca stems. The species occurred in 61% of the plots measured. Occupancy of E. pedicellatum at the individual tree-scale was influenced by stem diameter, study area, live crown length, plot P. glauca basal area, plot canopy cover and distance to open water. Our models for E. pedicellatum occupancy at the plot-scale identified study area, P. glauca density, deciduous basal area (Betula neoalaskana and Populus trichocarpa), and tall shrub cover (≥ 200 cm in height) as significant covariates. Our estimates of the DNPP population size increase the world population by at least tenfold to approximately 100,000 thalli. We suggest important topics for further research on E. pedicellatum.

Bole epiphytic lichens as potential indicators of environmental change in subtropical forest ecosystems in southwest China

Lichen epiphytes are applied as excellent environmental indicators worldwide. However, very little is known about epiphytic lichen communities and their response to forest dynamics in subtropical China. This paper proposes the applications of the cover, diversity, and functional traits of epiphytic lichens to assess environmental changes associated with succession in subtropical forests of southwest China. Bole lichens were sampled from 120 plots of eight representative forest types in the Ailao Mountains. Total cover, species richness, diversity and community structure of bole lichens differed significantly among forest types, and the highest cover and diversity occurred in the Populus bonatii secondary forest (PBSF). Sixty-one indicator species were associated with particular forest types and more than 50% occurred in the PBSF. Both cover and diversity of most lichen functional groups varied regularly during forest succession. Lichen pioneer species were not displaced by competitively superior species as succession proceeds and cyanolichens were more prevalent in secondary forests. The results also highlight the importance of habitat variables such as canopy openness, host diversity, forest age, tree size, the size of the largest tree, tree density, and basal area on the lichen community. Consequently, our findings support the notion that epiphytic lichens, in terms of cover, diversity, species composition and functional traits can be used as effective indicators for large-scale and long-term forest monitoring. More importantly, the narrowly lobed foliose group was the best candidate indicator of environmental conditions in this region. The combined application of lichen indicator species and functional groups seemed to be a more reliable and more powerful method for monitoring forest dynamics in subtropical montane ecosystems.

Fragmentation of Mediterranean oak forests affects the diversity of epiphytic lichens

The present study investigated a fragmented Mediterranean oak forest to evaluate so called edge effect on species richness and composition of epiphytic lichen communities colonizing tree trunks. The results showed that in Mediterranean oak forest patches, epiphytic lichen diversity and communities are significantly influenced by microlimatic variables related to the edge effect. Light influx rather than atmospheric humidity and temperature was the main driving factor affecting lichen diversity along the forest edge-interior gradient, while humidity is the prevailing factor inside the forest. It is concluded that forest fragmentation may have a heavy impact of epiphytic lichens, with the reduction and disappearance of typical forest species and the appearance of ubiquitous tolerant species, with an overall impoverishment and banalization of the lichen flora.

Contrasting responses of epiphytic and dead wood-dwelling lichen diversity to forest management abandonment in silver fir mature woodlands

In the Alps, many forests are under abandonment because of direct protection or the unprofitability of timber production. The objective of this study was to analyse the effect of silviculture abandonment on the species richness and composition of epiphytic and dead wood-dwelling lichens in silver fir woodlands. An abandoned and a currently non-intensively managed forest watershed of the eastern Italian Alps that were matched for topography, stand structure, plant community and history of use were selected and randomly sampled for the lichen diversity of their silver fir mature stands. Generalised linear mixed models were used for the analyses of the species richness, whereas the species composition patterns were explored by redundancy analysis. The diversity of both of the lichen guilds were explained by the microhabitat conditions related to the contrasting management regimes, but they had opposite responses to the abandonment of the silvicultural activities. The epiphytic lichen communities were richer in species in the managed than in the abandoned silver fir woodlands. However, the effect of a 50year management cessation on the epiphytic lichens may change in the long term when natural disturbances create gaps and increase the attributes of old-growth forests. The dead wood-dwelling lichen species richness was higher in the abandoned forest because an increased availability of types of dead wood is usually rare in managed forests. The dead wood-dwelling lichen communities of the managed forests were a subset of a more diverse community that was developing in the abandoned forest. Our results indicated that, in non-intensively managed silver fir mature stands, lichen diversity may benefit from the retention of logs and snags, which provide habitat features typical of old-growth forests.

Species Richness of Epiphytic Lichens in Coniferous Forests: the Effect of Canopy Openness

Epiphytic lichen communities were studied in old coniferous forests across Estonia to find out the effect of site openness on the lichen species richness. All lichen species were recorded on the basal 2 m of 105 Picea abies and 105 Pinus sylvetsris trunks. The canopy openness readings were taken with a spherical densiometer around every sampled tree. The number of species on the trunks of both tree species increased significantly with increasing canopy openness. Nine lichen species, e.g. Cladonia cenotea, Lecidea nylanderi, Platismatia glauca, were significantly favoured by higher light availability, and only one species, Coenogonium pineti, by lower light availability. The results demonstrate that in the coniferous forests higher light availability supports higher species richness of epiphytic lichens on the lower trunk of trees.