ABSTRACT. Semi-dry grasslands are among the most species-rich and valuable plant communities in the world, harbouring many specialised and threatened species. Most of these grasslands were traditionally maintained by grazing and haymaking. After the cessation of traditional management, protected areas were established, and conservation management was introduced to protect the most valuable habitats. However, recent changes in traditional land use, eutrophication and climate warming have had negative effects on the biodiversity of these grasslands. We asked whether plant species composition and richness change over time and whether the decline in habitat quality and plant diversity is less severe or absent in protected areas. We conducted two resurvey studies over 40 years in South Moravia (Czech Republic). One study focused on acidophilous dry grasslands and heathlands, and the other on basiphilous semi-dry grasslands. We identified significant changes in species composition in both acidophilous and basiphilous communities. Species richness, the proportion of habitat specialists and Red-List species decreased, while competitively stronger species with higher demands on nutrients, juveniles of woody plants and alien species increased. In the acidophilous grasslands, we also detected an increase in annual species and the negative impact of the invasive grass Arrhenatherum elatius on habitat quality. In the basiphilous semi-dry grasslands, there was a significant increase in species with higher demands on moisture, causing a transition to more mesophilous communities. These negative trends occurred both within and outside protected areas but were more pronounced outside. The main factor behind the changes appears to be the cessation of traditional management and natural succession supported by eutrophication.

ABSTRACT. ReSurveyEurope is a community initiative that establishes a new repository of data from resurveyed vegetation plots in Europe. ReSurveyEurope collects vegetation plots from all habitats. The first call for data provision was issued on 6 October 2020. All databases in ReSurveyEurope are stored and managed using the Turboveg program versions 2 and 3 at Masaryk University in Brno. Version 1.0 of ReSurveyEurope contains 274,396 observations (i.e. individual surveys of each plot) from 77,020 plots sampled in 442 independent resurvey projects included in 256 datasets. Of these, 62,431 (80%) are permanent plots, i.e. marked or geo-tagged plots, which allow for high spatial accuracy in resurvey. The remaining 15,873 (20%) plots are from resampling studies, in which plots from the initial survey were not exactly relocated. Four datasets, which together account for 28,470 (35%) plots, provide only presence/absence information on plant species, while the remaining 49,834 (65%) plots contain abundance information (e.g. percentage cover or cover-abundance classes such as the Braun-Blanquet scale). The oldest plots were sampled in 1911 in the Eastern Alps, while most plots were sampled between 1950 and 2022. Of those plots that could be classified to EUNIS habitat types, 50% were from grasslands, 21% changed their broad habitat type over time, 16% were from forests and 13% were from other habitat types. ReSurveyEurope is devoted to an inclusive and transparent governance and data usage approach based on slightly adapted rules of the well-established European Vegetation Archive (EVA).

ABSTRACT. Acceleration of anthropogenic impacts on the biosphere is observed since 1950s. Along with an exponential growth of environmental factors an increasing impact on plant communities is expected. In temperate forests, several drivers of vegetation change were already identified, particularly climate warming and eutrophication. However, acceleration of changes was not proved yet. To solve this hypothesis, we repeatedly re-surveyed 127 plots in the Western Carpathian forests (including oak, oak-hornbeam, beech, mixed mountain and spruce forests). Plots were established about 1966, firstly re-surveyed in about 2005, and secondly in about 2021. We compared diversity and species composition similarity measures of forest understories divided by time span (years) between the re-survey periods, getting the mean change per year. Alpha diversity measures (species richness, H´, J´) did not change in the herb understorey. Significant decrease as well as its acceleration was observed in the total herb cover. Mean annual decrease was 0.3% in the first period (1966 and 2005) and 1.0% in the second (2005−2021). Rapid and accelerating changes were also detected in the species composition change when the Bray-Curtis index increased annually by 0.015 up to 2005 and by 0.032 in the latest period. Mean species turnover reached 50 % (according to Jaccard index from presence/absence data) between the 2005 and 2021. We conclude that forest vegetation dynamics accelerates in the Western-Carpathians, manifested by increased rates of compositional and cover change. These findings have serious consequences for vegetation and habitat classification as well as for nature conservation.

Acknowledgements: This research was supported by the Scientific Grant Agency VEGA, project 1/0624/21.

ABSTRACT. Many terrestrial habitats across the globe are currently assessed as "threatened", and the extent to which existing protected areas effectively safeguard biodiversity is debated. With many ecosystem services depending on plants, reliable estimates of long-term vegetation change are needed as a benchmark for future monitoring and reporting, as well as to plan and undertake effective conservation measures. We hereby present VegTrends, a new EU-funded project aimed at i) providing a multi-habitat and multi-faceted assessment of temporal vegetation changes across plant communities and species; ii) evaluating the effectiveness of protected areas in conserving European habitats. Building on an unprecedented number of previously-disconnected datasets now included in the ReSurveyEurope database, VegTrends will allow producing the first comprehensive and representative report of temporal trends in the vegetation of European open habitats accounting for the effects of protection status (Natura2000 + Emerald Network). Besides assessing compositional shifts and quantifying changes in taxonomic, functional and phylogenetic diversity metrics, we will analyse trends in biological variables defining changes in conservation status (e.g. richness and cover of habitat specialist, threatened and alien species) and investigate whether they differ based on protection status. Moreover, we will identify driving mechanisms (turnover vs nestedness, gain vs loss) and test for the exceptionality of observed changes. This will allow pinpointing habitats and species that underwent the strongest changes, with important implications for habitat conservation.

ABSTRACT. In response to climate change many plant species shift their ranges towards cooler higher elevations to track their temperature niches, although they are lagging behind climate warming (e.g., Rumpf et al. 2018). On the other hand, rugged mountain topography provides a wide range of microclimatic niches within the same elevation which may serve as microrefugia in a warming world (Körner & Hiltbrunner 2021) - particularly northern expositions are notably cooler than other aspects (Winkler et al. 2016). Here we assess horizontal range dynamics of 183 vascular plant species of the Eastern Alps on 1,576 semi-permanent non-forested plots surveyed between 1911-1970 and resurveyed 2014-2015 (dataset from Rumpf et al. 2018). On average, these 183 species shifted significantly towards northern aspects. However, horizontal shifts were only significant in ~15% of the species, 85% of which moved to the north. Only 2% of the species shifted both upwards and towards the north. Changes in northness were idiosyncratic and not related to the species’ ecological indicator values (Landolt et al. 2010) for temperature, soil moisture or nutrients. We conclude that for a small subset of mountain plant species horizontal range shifts to cooler northern aspects may thus constitute an alternative (rather than complementary) strategy to escape rising temperatures.

ABSTRACT. High topographic variability has a strong impact on the distribution of plants in alpine landscapes. It has been hypothesized that through regulating near-surface temperature above the tree line it may sustain cold microrefugia for alpine plants and hence relax the need of shifting upward when climate warms. However, the effectiveness of these microrefugia relies on the premise that plant distribution in alpine landscapes is mainly controlled by fine-scale topographic variation rather than coarse-scale one. We tested this assumption by relating the distribution of 79 plant species and 10 community attributes across 900 1 m² plots in a landscape of the Austrian Alps spanning 1,677 elevational metres to 13 topographical descriptors at resolutions between 1 and 301 m. We found that the spatial distribution of most species and most community traits were better explained by topographic variation at coarser scales (> 20 m). The pattern is stronger in the case of the distribution of individual species than in case of community properties, where the effect of the fine-scale topography is relatively stronger. Fine-scale topography is more clearly reflected in moisture than in temperature requirements of species. The elevational gradient, not topographic variation at any scale, is the single most important driver of species distribution and variation of community-attribute in the area studied. We hypothesise that our results reflect an underestimated impact of neutral, dispersal-related processes on alpine plant distribution. Mass effects and dispersal limitation can override environmental filtering at fine scales and will thus compromise the survival of cold-adapted plants in small and fragmented refugia under climate warming.

ABSTRACT. Ireland’s largest terrestrial habitat is grassland, though much of this grassland has been agriculturally improved and as a result, the original species assemblages have been lost, therefore, habitat restoration is the desired option for biodiversity enhancement. When spontaneous restoration is being considered, the health of a habitat’s seedbank can directly correlate with restoration success, particularly when remnant habitat is not present. How a seedbank may degrade over time depends on the type of habitat that was present. Grassland is generally a stable habitat, and as such, seeds within the seedbank may degrade quickly after land use change. However, a grassland seedbank study has not been completed to date in Ireland. The seedling emergence method was used to assess the seedbank within the lowland grasslands of Killarney National Park, Co. Kerry. Soil seed samples were collected from lowland fields during October 2022 and seeds grown. The species present in the seed bank throughout the park grasslands have been estimated. A vegetation survey was completed in July 2022 to compare diversity of existing vegetation versus this seedbank. The preliminary results indicate that the seedbank has been somewhat degraded, however, there were species within the seedbank that were not recorded in the vegetation survey. These included graminoid species such as Trisetum flavescens and other oat grasses. There were also additional common ruderals within the seedbank. No rare target species were germinated from the seed samples collected. Conversely, species such as Rhinanthus minor were absent from the seed bank, yet present in the vegetation survey. This study will inform semi-improved lowland grassland biodiversity restoration projects and shed light on the self-restorative capacity of these grasslands. It will also indicate if the most common methods used to evaluate seedbanks in mainland Europe are as effective in Ireland.

ABSTRACT. Nature is facing huge challenges worldwide and the future of many endangered plant species is pitch dark if no direct action is taken. This clearly holds for the Netherlands, with more than 17 million inhabitants living in an area of just a little more than 40,000 square kilometres. Here, more than one third of the 1,500 indigenous plant species are on the National Red List of Vascular Plants, of which 70 are critically endangered. The Dutch government has set aside no less than 26 billion euros to restore nature as quickly as possible, with 2030 as a target. In the light of this, the role of gene banks has come under attention: if we succeed to restore the abiotic conditions, we have to be sure that the species are still present. We launched the Dutch Living Archive as an important tool of the national rescue plan. In this presentation, we will focus on restoration plans for a set of species, discussing both options and foot traps. We selected three examples out of a total of about one hundred plant species for which ‘action plans’ are set up in the Netherlands. There is no single roadmap for reinforcing existing impoverished populations and reintroducing species at former sites where the site conditions have been improved. How to operate will be illustrated for three strongly endangered plant species in the Netherlands: Geum rivale, Daphne mezereum and Puccinellia rupestris. For reaching maximal results in reinforcement and reintroduction, universities and other research institutes have to collaborate with nature conservation agencies as well as policy makers at different levels.

ABSTRACT. The practice of litter raking has been widespread in forests throughout Europe and has left a significant legacy on forest ecosystems. Recently, litter raking has been considered as a conservation tool to restore declining plant species diversity due to increased nitrogen deposition and abandonment of traditional management. To address this, several experiments have been set up since the 1990s to monitor how forest ecosystems respond to history-inspired management interventions. We compiled a dataset of 156 permanent forest vegetation plots from the Czech Republic, Poland, Slovakia, Germany and Switzerland. We investigated whether there is a general pattern in the effect of litter raking on the diversity and composition of understorey vascular plants. Specifically, we focused on changes in species richness, taxonomic heterogeneity and Ellenberg indicator values for nutrients and soil reaction. We found a consistent increase in species richness, mostly beginning in the third year of the experiment. The response of taxonomic heterogeneity to litter raking measured as a distance from the centroid was highly variable between sites, with both increases and decreases. In general, based on Ellenberg indicator values, species composition shifted towards flora with lower nutrient levels and lower soil reaction but the changes were not consistent between sites. This trend was stronger on sites with originally acidophilic and oligotrophic flora, such as acidophilous oak forests. The results of this study suggest that the response of understorey species diversity and composition to litter raking may vary depending on the initial site conditions, such as soil and vegetation type. The results may also help to select sites suitable for litter raking as a conservation management tool.

ABSTRACT. Invasive species spreading control and restore ecosystems, like semi-natural grasslands are among the EU’s biodiversity strategy targets. Successful restoration of lands invaded by alien plant species has to consider three stages: invasive species removing, habitat restoration, and further management. Among species that have a strong negative impact to biodiversity and frequently invade grasslands in Central Europe are Solidago gigantea and S. canadensis. We present results of eight years experiment aimed to restore semi-natural grassland, testing different methods of removing invasive Solidago species and seed application. Three kinds of removal treatments (herbicide spraying, rototilling, turf stripping) and two seed addition methods (direct sowing of a fast-growing grass species mixture, and spreading of fresh hay collected from a semi-natural meadow) were examined. The experimental plots were mowed twice a year, and the vegetation composition was assessed every year. Obtained results show that lands degraded by invasive species can be restored to valuable grasslands, but the process needs time. The effectiveness of herbicide treatment was not superior to other Solidago removal methods, indicating that methods that are less harmful to the environment can be used. The use of fresh hay as a seed source was not only beneficial to biodiversity but also most effective in suppressing the invasive species. The recommended method of management is regular mowing twice a year. It should be emphasized that a realistic evaluation of restoration outcomes should be performed from a longer time perspective. The short-term observations document only the temporal stages of vegetation succession, which could differ substantially after 8 years, resulting in misleading conclusions regarding the excellent effect of herbicides or commercial seed mixtures of fast-growing grasses on long-term restoration success (Szymura et al. 2022).

ABSTRACT. Kazue Fujiwara,

Graduate School in Bionanoscience, Yokohama City University,　kazue05fujiwara@gmail.com

The original idea and models for the mini-forests envisioned by Akira Miyawaki came especially from Autobahn forests and conserved Urwald in Germany and the Netherlands, where he had studied the potential natural forests according to the Tüxen school of phytosociology. The diversity of natural forests is high in Europe, but Prof. Miyawaki also added his agricultural experience to the idea of potential natural forests. The most stable forests occur on stable topography, with mesic, rich soil and good drainage. In Europe these are Quercus and Fagus forests, along with forests dominated by Ulmus or Carpinus on alluvial areas and valley slopes. In Japan, Miyawaki created natural forests in the evergreen broad-leaved forest region. His method involves: 1) potted saplings (Miyawaki’s idea) of dominant species of the potential natural forest; 2) soil preparation on the planting sites; 3) dense, random, mixed-species plantings; 4) planting activity by local students and townspeople, for environmental education; and 5) mulching with rice straw, weeds or bark chips to reduce evaporation and soil erosion, add nutrients, foster soil animals, and suppress weeds. Dense planting encourages competition and coexistence among seedlings, encouraging early growth. Such forests also serve as habitats for mammals and birds, mitigate disasters (fire, tsunami, flood, etc.), and protect against wind, salt spray, sand, noise, dust, etc., all of which treat various SDG goals. There is a Miyawaki mini-forests in Istanbul (Sango Co.), and Prof. B. Schirone (Tuscia, Italy) will describe his experiences in a talk at the IAVS meeting in Coffs Harbour. Restoration methods of evergreen broad-leaved and deciduous forests differ in planting density, due to sapling shape. European sclerophyll Quercus needs greater density and admixture with deciduous Quercus.

ABSTRACT. Miyawaki’s reforestation method is at present the most sophisticated among the current approaches to forest and environment restoration. According to it, large amounts of seedlings of native late successional trees should be planted in plots on fertilized, artificially recovered organic topsoil. It basically mimics natural succession enabling the planted stands to grow and mature much more quickly than with traditional afforestation methods. Urban deforested areas became early target-scenarios of these plantations, basically fostering the body of knowledge on topics related to the planning, design and the establishment of urban and peri-urban woody vegetation. Basic foundations of the method involve the knowledge of local succession, soil dynamics and potential natural vegetation. Nevertheless, criticism is raised concerning the high costs, frequent failure in dry areas and loss of diversity. The core paradigm “natural potential vegetation/native, late successional trees”, apparently is the crucial point. Criticism to the method does basically come from disregarding these basic requirements. Moreover, the computing of diversity before and after the establishment of the stands is highly misleading. The interpretation of changes in diversity after the establishment of the plantation, often is biased by the obvious disappearance of what is a stock of ruderal or early successional species, once in situ, which is evaluated as bad result, ignoring local natural vegetation dynamics and that most extant late successional old growth forest stands in the temperate and Mediterranean forests can be extremely species poor in the understorey. The Scientific Community of Vegetation Science must re-emphasize the basic geobotanical foundations of the method and watch over its development, in order to prevent conceptual bias, misinterpretations of failures or misleading developments of the technique and revert to Miyawaki’s original solid ground in geobotany and phytogeography.

ABSTRACT. One of the most common invasive plant genera in Europe and Asia, with a strong environmental impact, is Solidago of North American origin. Member states of the European Union are required to prevent the introduction, control, or eradication of invasive alien species due to the significant environmental impact of biological invasions (European Community, 2014). Two steps are required for the long-term successful eradication of invasive species: the removal of invasive plant species and the ensuing restoration of the habitat (Reid et al. 2009). The presented study aims to find the best, environmentally friendly method to control Solidago invasion and restore the semi-natural meadow on the site invaded by Solidago. For this purpose, the two-factorial experiment was established in 2020 using: (1) different methods of seed introduction [sowing the seed mixture of pasture grasses (4 species); pasture grasses with legumes (6 species); seeds from the semi-natural meadow (37 species); and application of fresh hay (47 species)], as well as (2) different frequency of mowing (once, twice, and three times). The experiment area was mowed and the soil was prepared using a rototiller prior to seed application. The species compositions with coverage were recorded before the first mowing in two years (2021 and 2022). The cover of Solidago in 2021 and 2022 significantly decreased by mowing twice and three times and the highest change in seeds from the semi-natural meadow with one-time mowing was observed. The species richness was influenced by a combination of factors: seed introduction methods and mowing regimes. The highest species richness was observed in the semi-natural meadow with mowing three times. The results revealed that all the mowing regimes and seed introduction methods are effective in Solidago stand reclamation, reducing an average of 80% of Solidago coverage from the beginning to after three years.

ABSTRACT. Alien plant species are considered a major driver of the rise of novel ecosystems and a serious threat to biodiversity. To study their ecology and dynamics at large scales, high-quality checklists are needed. Although several attempts to compile large databases of alien plants have been made, especially in Europe, they were constrained by the limited availability of regional checklists or they focused on selected groups of alien plants (e.g. GloNAF on naturalized aliens). We assembled >100 alien plant checklists for European countries and identified large gaps in their completeness and comparability. To overcome these inconsistencies, we started to update the lists of alien vascular plants for individual countries based on several sources available. We considered regional checklists (including unpublished ones), large databases, namely DAISIE, GloNAF and the Euro+Med PlantBase, and occurrence data from the GBIF and EVA database of vegetation plots. We carefully standardized all these input data to the same nomenclature following the Euro+Med Plantbase concept or POWO in case of taxa not included in Euro+Med. We created a database, in which each species is assigned a native or alien status within 55 countries or regions (large islands were treated separately). If available, we also provide the residence-time status (archaeophyte, neophyte), invasion status (casual, naturalized, invasive), and region of origin (e.g. North America, tropical Asia). If the sources differed in status assigned to the same taxon, we treated such cases individually with the help of regional experts. Our comprehensive database will enable large-scale syntheses focused on alien plants in Europe. We plan to make it open and regularly update the information in the recently developed FloraVeg.EU database, comprising characteristics of the European flora and vegetation. We also plan to further contribute our data to the Euro+Med and GloNAF databases.

ABSTRACT. The ecological indicators of Ellenberg (EIVs) for species and subspecies have been compiled for the Iberian flora. Indicator values for light (L), temperature (T), moisture (F), soil reaction (R), nutrient availability (N) and salinity (S) were assigned to 2500 species using the nine-degree, or 12-degree for moisture and 10-degree for salinity using the ordinal scales proposed by Heinz Ellenberg for the flora of Germany. We have used the original Ellenberg indicators (Ellenberg et al. 1991) as a baseline, together to datasets from other reference floras from close countries: Jiménez-Alfaro et al. (2021) from the Cantabrian Range; Julve et al. (2012) from France; Pignatti et al. (2005) and Guarino et al. (2012) from Italy; Böhling et al. (2002) for the South of Greece and Landolt et al. (2010) for Switzerland. We have used the reciprocal averaging method (Chytry et al. 2018) to fill values of the EIVs for the species of different vegetation datasets obtained from SIVIM (Font et al. 2012). Until now we have revised: therophytic vegetation, high-mountain vegetation, Quercus pyrenaica forest, saline vegetation and shrublands and scrublands. The total number of plots have been 45000 aprox. and they were analyzed by Juice v.7.1 (Tichý 2002, Tichý et al. 2023) and some cases also with the R package FD, function functcom (Laliberté et al 2014). Taxa with an initial EIV in the floras of reference but absent from the vegetation plots were left without EIVs. We finally calculated Spearman correlations between the final EIVs and those reported in the original floras to test whether they retained a similar ecological meaning. The Kernel probability was also used to analyze the probability of variables to reach a determined value. The results showed a final list of species with new indices and also species that were present in the comparison floras that now have a value for those EIVs.

ABSTRACT. Vegetation classification traditionally uses the phytosociological approach, whereby species-by-plot matrices are directly subjected to analyses. The resulting groups are interpreted ecologically, which is often mirrored in the English names of syntaxa; for instance, the Arrhenatherion elatioris is circumscribed as “Mesic mown meadows on mineral-rich soils in the lowland to submontane belts of temperate Europe”. Hence, particularly at the level of alliances and/or habitat types, classification based on ecological properties seems feasible, and classifying vegetation using mean ecological indicator values could be a worthwhile complement to the traditional phytosociological approach. I present first results, potential pros, cons and open questions concerning vegetation classification using indicator values. I analysed 1200 10-m2 relevés of Swiss open land vegetation that had been assigned to habitat types (alliances) using three different phytosociological methods. As a first proof of concept, I trained a linear discriminant analysis (LDA) model with six mean indicator values and ¾ of the relevés that had been consensually assigned to the same vegetation types by all three phytosociological methods. This LDA model correctly predicted the vegetation type of 85% of the ¼ consensus relevés used as test data. Another approach is mapping relevés within the multidimensional ecological space created by the indicator values. Thereby, ecologically extreme vegetation types like raised bogs can easily be delimited, whereas vegetation types that often overlap floristically also overlap in the indicator value space. Critical feedback and ideas on how to further implement and evaluate indicator-value-based classification approaches are highly welcome.

ABSTRACT. Ecological indicator value (EIV) systems of plants, which allow to assess the conditions of plots on the basis of species composition, are widely used in ecological studies of vegetation in Europe. Until recently there were many regional systems developed for a territory. However, these systems are inconsistent in scaling and plant taxonomy, which hinders their use for large-scale studies across the continent. Our goal was to create an indicator value system for all Europe based on the assessments in the regional systems. Study area: Europe (and closely adjacent regions). Methods: We used 31 regional EIV systems that have data on at least one of the five ecological niche dimensions: soil moisture (M) - 31 source systems, soil nitrogen (N) - 24, soil reaction (R) - 28, light (L) – 33, and temperature (T) - 23. We combined and unified the regional scales by harmonizing the scaling in an iterative approach. We derived consensus values of niche position and niche width for each combination of taxon x niche dimension. Thus, we got the European values scale, where 0 is the minimum value of the factor, and 10 is the maximum available in Europe. All analyses were performed in R. Taxon names were harmonized to the Euro+Med Plantbase. We validated our T values by correlating them with species niche data derived from GBIF. Results: In January 2023, we published the Ecological Indicator Values for Europe (EIVE) 1.0 with niche position and niche width for 14,835 taxa of vascular plants (14,714 for M, 13,748 for N, 14,254 for R, 14,054 for L, 14,496 for T). Future plans: Currently, we are working on EIVE 1.5 to cover also bryophytes, lichens and macro-algae plus some new and updated systems for vascular plants. Beyond that, future plans include adding further niche dimensions with the same consensus approach, combining EIVE with the European Vegetation Archive (EVA) as well as preparing additional regional versions of EIVE for major parts of Europe.

ABSTRACT. Bryophytes are a diverse group of land plants, but due to difficulties in their identification, they have rarely been included in biodiversity surveys. As they are found from sea level to mountain summits, they are ideal candidates for altitudinal studies. Analysis of bryophyte diversity was undertaken to elucidate the richness and floristic composition of the eight forest altitudinal belts along two Dinaric mountains. A total of 185 species (40 liverworts and 145 mosses) were encountered. The lowest total number of bryophytes is in the lowest holm oak (Fraxino orni-Quercetum ilicis Horvatić (1956) 1958) altitudinal belt and the highest in the complex of spruce communities (Vaccinio-Piceion Oberd. 1957). Patterns of alpha diversity were best described by the cubic regression function with diversity maxima approximately between 1.100 and 1.200 m a.s.l. The most prominent species turnover appears between boreal spruce and subalpine beech belts and between subalpine beech and pine Krummholz belts. Bryophytes exhibit the highest abundances in spruce and mixed beech and fir communities and the lowest in thermophilic (Oriental hornbeam and holm oak) communities. The diagnostic species of low-altitude thermophilic forests are Rhynchostegium confertum, Rhynchostegiella tenella, Fissidens taxifolius, Leptodon smithii, Zygodon rupestris, Frullania cesatiana, Orthotrichum diaphanum and Scorpiurium circinatum, of mixed beech and fir forests Exsertotheca crispa and Ulota crispa, of spruce forests Rhytidiadelphus loreus, Plagiothecium laeutum, Chiloscyphus polyanthos, Polytrichum formosum, Dicranum tauricum, Buxbaumia viridis and Herzogiella seligeri, of subalpine beech forests Paraleucobryum sauteri, Leskurea saviana and L. incurvata, while of pine Krumholtz vegetation Rhytidiadelphus triquetrus. The altitudinal zonation of bryophytes demonstrates that these plants respond to elevational gradient in terms of species richness, floristic composition and phytogeographical patterns.

ABSTRACT. Aspen forests are important habitats for many organism groups, including bryophytes. Old-growth aspen forests provide variety of rare bryophyte species. Bryophyte communities in aspen forests are threatened by forestry activities, especially low cutting age in commercial aspen forests. It is important to understand how bryophyte communities change with the forest age. The aim of the study was to explore bryophyte diversity in relation to substrate characteristics along aspen forest chronosequence. The study was carried out in aspen forest stands representing three age classes – young, middle, and old-growth forests. Bryophytes were studied on three substrate groups – ground, logs, and living trees. On each substrate bryophyte cover as well as substrate characteristics were evaluated. Diameter and tree species were evaluated for the living trees. The presence of bark, decay stage, diameter, and tree species were recorded for logs. The cover of forest litter was evaluated for ground plots. Our study gives a detailed analysis of the importance of each substrate to bryophyte diversity along aspen forest chronosequence.

ABSTRACT. An extensive survey of aquatic vegetation in Croatian watercourses was conducted to assess the ecological status according to the Water Framework Directive. Macrophyte cover and abundance were assessed along 100 m-long transects using the extended Braun-Blanquet scale. The survey yielded 80 bryophyte species from 208 sites on 144 different watercourses. Direct multivariate ordination of vegetation data paired with 18 environmental variables revealed that freshwater bryophytes and their assemblages were segregated along the gradients of water chemistry and the proportion of natural and urban area within the catchment. Furthermore, the ecological responses of individual species were explored with generalized additive models. The majority of the species preferred watercourses with unaltered catchments, clean, well-oxygenated water with low nutrient and organic matter content, as well as low electrical conductivity. However, the most frequent and widely distributed species, such as Fontinalis antipyretica, Rhynchostegium riparioides, Cratoneuron filicinum, Fissidens crassipes, Cinclidotus fontinaloides and C. riparius, had a wide ecological tolerance. Several species with narrow ecological niches, indicative of good water quality were identified as well, while only Riccia fluitans and Leptodyctium riparium had optima in hypereutrophic waters with high electrical conductivity and organic content and were frequently associated with a high share of intensive agriculture within the catchment area. When only bryophyte-dominated sites were considered, five communities segregated along the gradient of several climatic, physiographic and water chemistry parameters were recognized. The geographical patterns of the bryophytes and their communities revealed that clean, fast and cold karstic rivers with larger substrates and larger catchment areas, which are characteristic of the Dinaric Ecoregion provide the most suitable habitats supporting their greatest diversity.