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The article presents 80 relevés of bryophyte communities on living trees and dead wood sampled within Holosiivskyi National Nature Park (Kyiv, Ukraine). They are referred to 16 associations of 5 classes (Frullanio dilatatae-Leucodontetea sciuroidis, Cladonio digitatae-Lepidozietea reptantis, Neckeretea complanatae, Hylocomietea splendentis, Platyhypnidio-Fontinalietea antipyreticae). Most frequent are communities dominated by Hypnum cupressiforme and H. pallescens of the class Frullanio dilatatae-Leucodontetea sciuroidis (on bark of living trees) and Brachythecium rutabulum of the class Cladonio digitatae-Lepidozietea reptantis (on dead wood). In mesic forests, trees are usually not inhabited by bryophyte communities. Much more often, they occur in wet forests, near water, and in mesic forests in ravines. Four associations are reported in Ukraine for the first time: Callicladietum haldaniani LeBlanc 1963, Brachythecio rutabuli-Plagiomnietum cuspidati (Felföldy 1941) Plamada 1982, Brachythecio rivularis-Hygrohypnetum luridi Philippi 1965, and Leptodictyo riparii-Hygroamblystegietum varii Hugonnot et Celle 2013.

The dispersal ecology of tropical non-vascular epiphytes has rarely been experimentally investigated. We studied epiphyte colonisation on 1 × 1 m polyethene nets placed for four years at seven sites at different elevations in montane forests in the Taita Hills, Kenya. During the first year the nets were also used to measure fog deposition. We predicted that differences in growth conditions would affect colonisation and subsequent growth of non-vascular epiphytes and result in clear differences in epiphyte cover and biomass, and community composition among sites. After four years the nets were taken down for determination of epiphyte cover and biomass. The diversity of established liverworts and macrolichens was also examined. Many liverwort and macrolichen species established diverse communities on the nets placed in the moist upper-montane zone. This was in contrast with the situation in the drier lower-montane zone where only green algae and crustose lichens were able to colonise most nets. Light intensity was an important determinant of epiphyte community composition, with liverworts dominating on nets under closed forest canopies and lichens dominating at more open sites. Atmospheric moisture was also important, with lichens benefiting from abundant fog deposition at open and windy sites. The dry weight of epiphytes (per unit area) on lichen-dominated nets was greater than on liverwort-dominated nets, while the highest cover was generally observed on liverwort-dominated nets. Our results demonstrate that polyethylene nets can be effectively used to study colonisation of non-vascular epiphytes as well as the abiotic and biotic factors controlling epiphyte colonisation and community composition in tropical forests. The liverworts Acanthocoleus chrysophyllus and Diplasiolejeunea kraussiana were new additions to the Kenyan bryophyte flora.

Questions: Despite the increasing scientific interest in distance decay of compositional similarity in ecology, the scale-dependence of geographical vs environmental control on distance decay of biological communities has not been properly addressed so far. The present work highlights the relative importance of niche-based processes vs dispersal limitations on distance decay patterns of epilithic bryophyte assemblages at different spatial scales. Location: Serra de Sintra, central Portugal. Methods: We adopted a nested sampling design with 32 selected sampling sites in each of which two clusters, each with five rocks, were surveyed. Each cluster was characterized by a set of 15 macro-scale variables, which were divided into environmental and anthropogenic. For each rock eight micro-scale variables were recorded. Partial Mantel tests were used to assess the relative importance of geographical and environmental distance on community dissimilarity for each grain size (site, cluster, rock). Quantile regressions were used to describe the decay patterns of community similarity with respect to geographical and environmental distances. Ordination analyses and variation partitioning techniques were applied to assess the pure and shared effects of measured variables on bryophyte community composition. Results: Environmental distance based upon macro-scale predictors was significantly correlated to community similarity, while no significant correlation was found for ecological distance calculated for micro-scale predictors, except at the largest grain size. The decrease of community similarity with geographical and environmental distance was thus consistently strengthened with increasing sample grain. Compositional variation was best explained by anthropogenic variables. Conclusions: The relative importance of environmental vs geographical distance on compositional similarity in epilithic bryophyte communities varies with the spatial scale of the predictors and with the sample grain. The decrease of similarity with increasing distance is related to changes in habitat features, especially those driven by human disturbance, while is weakly affected by variations in substrate features.

Question: Is there, at the macro-habitat scale, a relationship between the fraction of evergreen forests and the presence probability of epiphyllous liverworts? Can these two parameters be estimated and mapped using an NDVI-based indicator that is derived from time-series of SPOT-VGT imagery? Location: Southern China. Methods: Applying the ISODATA algorithm, we classified SPOT-VGT NDVI time-series imagery and produced an NDVI map at 1-km2 resolution containing 128 NDVI classes. That map and the National Land Cover Map of China (2000) were used to prepare a scheme for field sampling. For 537 1-km2 areas, located in 19 blocks of 100 km × 100 km, field data were collected. They represented 51 preselected NDVI classes that were assumed to contain evergreen forests. Data on the fractions of forest and evergreen forest, the fraction of evergreen forest in forest present and presence probability of epiphyllous liverworts were regressed against different NDVI class-specific indicators by means of weighted least-squares regression (WLSR). Results: The SPOT-VGT NDVI for March was found to best explain the variation between 1-km2 areas in the presence probability of epiphyllous liverworts (R2 = 0.64; linear relationship; RMSE = 0.38) as the area fraction (%) of evergreen forest (R2 = 0.90; exponential relationship; RMSE = 6.1%). Epiphyllous liverworts were only found within 1-km2 areas when the SPOT-VGT NDVI value for March was more than 0.50 (model estimate: 0.43 ± 0.20) and the fraction of evergreen forest in 1 km2 was above 14% (model estimate: 5 ± 35%). The estimation errors (with 95% confidence interval) of these two relationships were calculated using a bootstrap resampling method with 1000 replications; they were, respectively, 0.49-0.76 and 0.85-0.94 for R2, and 0.11-0.23 and 5.2-11.9% for RMSE. Other positive relationships were found between the presence probability of epiphyllous liverworts and the fraction of evergreen forest (R2 = 0.64, linear relationship; RMSE = 0.38) and between the fraction of evergreen forest and forest within 1-km2 areas (R2 = 0.80, linear relationship; RMSE = 29%). Conclusion: We show that for southern China, the fraction of evergreen forest and the presence probability of epiphyllous liverworts can directly be inferred by making use of SPOT-VGT NDVI imagery. The findings are fully consistent with earlier reported hotspots for epiphyllous liverworts. At the macro-habitat scale, the presence probability of epiphyllous liverworts proved quantitatively related to the fraction of evergreen forest. This suggests causal relationships with patch size and/or rainfall patterns. We believe that the derived maps may serve as a foundation for a range of further studies. © 2012 International Association for Vegetation Science.

Vegetation classification consistent with the Braun-Blanquet approach is widely used in Europe for applied vegetation science, conservation planning and land management. During the long history of syntaxonomy, many concepts and names of vegetation units have been proposed, but there has been no single classification system integrating these units. Here we (1) present a comprehensive, hierarchical, syntaxonomic system of alliances, orders and classes of Braun-Blanquet syntaxonomy for vascular plant, bryophyte and lichen, and algal communities of Europe; (2) briefly characterize in ecological and geographic terms accepted syntaxonomic concepts; (3) link available synonyms to these accepted concepts; and (4) provide a list of diagnostic species for all classes. Location: European mainland, Greenland, Arctic archipelagos (including Iceland, Svalbard, Novaya Zemlya), Canary Islands, Madeira, Azores, Caucasus, Cyprus. Methods: We evaluated approximately 10 000 bibliographic sources to create a comprehensive list of previously proposed syntaxonomic units. These units were evaluated by experts for their floristic and ecological distinctness, clarity of geographic distribution and compliance with the nomenclature code. Accepted units were compiled into three systems of classes, orders and alliances (EuroVegChecklist, EVC) for communities dominated by vascular plants (EVC1), bryophytes and lichens (EVC2) and algae (EVC3). Results: EVC1 includes 109 classes, 300 orders and 1108 alliances; EVC2 includes 27 classes, 53 orders and 137 alliances, and EVC3 includes 13 classes, 24 orders and 53 alliances. In total 13 448 taxa were assigned as indicator species to classes of EVC1, 2087 to classes of EVC2 and 368 to classes of EVC3. Accepted syntaxonomic concepts are summarized in a series of appendices, and detailed information on each is accessible through the software tool EuroVegBrowser. Conclusions: This paper features the first comprehensive and critical account of European syntaxa and synthesizes more than 100 yr of classification effort by European phytosociologists. It aims to document and stabilize the concepts and nomenclature of syntaxa for practical uses, such as calibration of habitat classification used by the European Union, standardization of terminology for environmental assessment, management and conservation of nature areas, landscape planning and education. The presented classification systems provide a baseline for future development and revision of European syntaxonomy. info:eu-repo/semantics/publishedVersion

The classification of synusial epigeic and epiphytic bryophyte communities of forest coenoses of forest-steppe zone of Ukraine The syntaxonomical classification and characteristics of synusial epigeic and epiphytic bryophyte communities of forest coenoses of forest-steppe zone of Ukraine is presented in this paper.