Orthotrichum pulchellum is a species of epiphytic moss in which a significant expansion from the oceanic part of Europe to the east of the continent has been observed in the recent two decades. The improvement in air quality in Central and Eastern Europe, but also climate change, probably plays a role in this. This study shows what direction of its spreading we can expect in the future. Ecological niche modeling (ENM) is a widespread method to find out species niches in environmental and geographical space, which allows us to highlight areas that have a higher probability of occurrences of the studied species, based on identifying similar environmental conditions to those already known. We also made predictions for different future scenarios (CMIP5 climatology datasets for the years 2041-2060). Because we were not able to distinguish between historical and newly settled areas, and so, had to use some of the traditional approaches when modeling invasive species, we proposed to use niche clusters based on environmental layers to split the data of all known occurrences and make models separately for each cluster. This approach seems reasonable from the ecological species point of view because using all the morphologically same samples could be misleading. Altogether, 2712 samples were used from three separate niche clusters. For building the models, the Maxent algorithm was used as a well-tested, well-accepted, and commonly used method.

• Klíčová slova
• Maxent, bryophytes, climate change, distribution, ecological requirements, epiphytic moss, expansion, species distribution modeling,
• Publikační typ
• časopisecké články MeSH

Bryophytes are commonly used in biomonitoring heavy metal pollution, whereas the bioindicative value of bryophyte communities is a less known issue. The aim of the present study is to recognize the utility of the bryophyte community's structure in the assessment of soil condition in heavy metal-polluted, dry grasslands. The study plots are examined with respect to bryophytes; vascular plants; concentrations of Zn, Pb, Cd, and As in the soil; total nitrogen and organic carbon content in the soil; and soil pH. The results show that both bryophyte species richness and composition greatly depend on soil chemical characteristics, including heavy-metal pollution levels and soil pH. Three groups of species are distinguished: (1) species sensitive to pollution growing on acidic soils, (2) nonspecific species inhabiting a wide spectrum of heavy metal-polluted sites, and (3) species preferring polluted and alkaline soils. Our study reveals a gradual replacement of the bryophyte species alongside increasing soil pollution and alkalinity. This proves that bryophytes are highly responsive to soil factors and the changes in bryophyte composition may indicate the soil condition of a certain site. Furthermore, high concentrations of heavy metals in the soil and an alkaline pH positively affect bryophyte species richness. Consequently, such sites could be considered as biodiversity hotspots for terrestrial bryophytes in post-industrial landscapes.

• Klíčová slova
• bioindication, bryophytes, heavy metals, soil pH, soil pollution, species richness,
• Publikační typ
• časopisecké články MeSH

Bryophytes and lichens are outstanding bioindicators, not only of the plant community in which they develop, but also the substrates on which they grow. Some epiphytic cryptogams, particularly the rare ones, are stenotopic and require a long habitat continuity, for example substrates such as old trees. It could also be a tea plantation, this is because the shrubs are not felled, and most of them may have several dozen years. In addition, the shrubs are not subject to sudden changes in microclimatic conditions as only the young leaves are harvested. As the importance of tea plantations as host plants for mosses and lichens has not yet been studied, the present study examines the species diversity of cryptogams of two tea plantations in Georgia (Caucasus). The study also examines the phytogeography, spatial pattern, environmental conditions and ecological indicators of the cryptogams. Thirty-nine cryptogam taxa were identified; typical forest taxa dominated, even in the absence of typical forest communities. Some of these species are obligatory epiphytes, rare or even critically endangered in most European countries (e.g., Orthotrichum stellatum, O. stramineum, Lewinskya striata). The fairly abundant record of such species on tea plantations indicates the importance of these phytocoenoses for the preservation of rare species, and indicates that these habitats are hot spots for these cryptogams in otherwise changed envirnonment. Additionally, as indicated the analysis of the species composition of individual plantations and the mathematical analysis made on this basis, plantations differ from each other. Another interesting result is also the spatial distributions of cryptogams on tea bushes resemble those of forest communities and lichens seems to be more sensitive than bryophytes to antropogenic changes of environment.

• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH