This study investigated the genetic and morphological variability of critical populations of Quercus petraea s.l. in southern Europe considering taxonomic and biogeographical issues. Ten EST-SSR markers were applied on sixteen populations of Q. petraea s.l., including Q. petraea subsp. petraea, Q. petraea subsp. austrotyrrhenica, Q. dalechampii auct non Ten, and Q. banatus, to assess genetic variation within and among populations using specific indices. Genetic structure was analysed using Bayesian clustering. Eight populations of potentially interfertile white oaks such as Q. pubescens (5) and Q. robur (3) were included in the overall dataset (24 populations) for comparison. Multivariate analysis procedures were applied to analyse genetic relationships among populations. The morphological variability of oak individuals was assessed only on the Q. petraea s.l. populations based on traits observed in leaves, twigs, and acorns. The patterns of covariation between morphological traits, taxonomic identity, and the geographical distribution of sessile oak populations were also investigated. The analysis on the overall dataset revealed four main genetic clusters for Q. petraea s.l.: one of possible ancestral origin, one occurring mainly in the Balkans, one spread across southern Italy, and one distributed primarly in western and central Europe. From a morphometric perspective, only a few leaf morphological traits exhibited variation trends correlated with the genetic structure pattern. Considerable overlap was found among populations within the Q. petraea collective group from both the genetic and morphological side. The variability observed was insufficient to distinguish species other than Q. petraea (Matt.) Liebl. (i.e. Q. dalechampii auct. non Ten., Q. banatus Kučera). However, all Q. petraea s.l. populations were found to be clearly distinguishable from the Q. robur subsp. robur and Q. pubescens subsp. pubescens populations included in the dataset as outgroups.

ABSTRACT Aim Long‐term vegetation study through resurveys is essential for quantifying how biodiversity changes over time. The accuracy of resurvey data is influenced by plot relocation errors, arising from the spatial uncertainty of historical plot locations. Preferential location of resurvey plots potentially underestimates vegetation change in time, whereas random location may overestimate it. To address these methodological issues, we compared preferential and random relocation approaches to assess how plot location error influences observed temporal vegetation changes, focusing on diversity patterns across two common grassland types in Central Europe. Location Northeastern Austria and the southern Czech Republic. Methods We compared two methods for locating plots in resurveys at 50 sites along the Austrian‐Czech border: (a) resurvey plots located preferentially by the surveyor in the field in a place with vegetation similar to that described in the historical plot and (b) resurvey plots located randomly within a 300‐m spatial buffer around the probable location of the historical plot, within the same land‐cover type. We then compared changes in species richness, composition, and Ellenberg‐type indicator values between the two resurvey plot location methods. Results Across the entire dataset, species richness change and the Jaccard dissimilarity index were lower in the preferentially located than in the randomly located plots, while other metrics (species richness, number of species lost and gained, species composition, top winners and losers, Ellenberg‐type indicator values) showed no significant differences. In mesic grasslands, the resurvey plot location approach had the greatest effect on species richness. In contrast, in dry grasslands, it introduced uncertainty into the detection of compositional changes. Conclusions While both approaches yielded overall similar results, resurvey plots located preferentially indicated smaller changes in species richness and composition change than random plots. Results in resurvey studies based on quasi‐permanent plots should therefore be interpreted with caution, as plot location may affect temporal change detection in long‐term vegetation assessments.

This editorial of Vegetation Classification and Survey (VCS) focusses on how to prepare good synoptic tables. While synoptic tables are a core element for the standardised documentation of classification schemes, we regularly find that authors are challenged with preparing them in a concise and informative manner. Thus, we explain the key aspects of synoptic tables and how we handle them in VCS. The central information should always be the percentage constancy, not a constancy class (loss of information) nor the phi-value or any other measure of fidelity (because these depend on which other columns are included in the table). While in the main text there is usually only space for a shortened synoptic table (which should include the most frequent companion species), it is crucial that a full version is provided in the supplementary material, and the criteria for shortening and sorting should be documented transparently. On a more general note, VCS is generally doing well with a first Journal Impact Factor of 3.0 being published and the CiteScore constantly increasing. Finally, we present the four Editors’ Choice articles of the year, among which Joelson et al. (2025; Vegetation Classification and Survey 6: 37–56) won the Editors’ Award 2025. Abbreviations: VCS = Vegetation Classification and Survey.

Buddleja davidii Franch. is a Chinese ornamental plant that has become successfully naturalised and potentially invasive in most of Europe over the past century. Regarded as a species of unstable and disturbed sites, its ecological niche, invasiveness, and syntaxonomy have often been overlooked. In this study, we examined plant communities in which the species occurs in Slovenia and Europe using multivariate methods, focusing on differences in their ecology, taxonomical and functional diversity. To evaluate the invasiveness potential of B. davidii in communities it inhabits, we tested the extent to which its cover explains variation in Shannon–Wiener’s diversity index, evenness, disturbance severity and frequency indices, proportions of life forms, Grime’s life strategies and neophytes’ cover and number, using linear regression. Our results show that B. davidii has its ecological optimum in various types of shrub communities, primarily in riparian zones and abandoned quarries, which represent newly proposed subassociations of the typical Buddlejetum association. Communities with B. davidii can withstand varying levels of disturbance and generally consist of species with a competitive life strategy, while the most dominant life forms are hemicryptophytes and phanerophytes. Increasing cover of B. davidii accounted for little variation in taxonomical and functional diversity, and this effect was the most prominent in riparian shrub communities, followed by the Buddlejetum association and communities on wall crevices. Occurrences in different plant communities confirm the species’ ecological plasticity, whereas its invasiveness is relative, due to its limited relationship with the diversity parameters.

The goal of the EcoVeg approach is to fully describe and classify the diversity of the Earth's terrestrial ecosystems based on vegetation and ecological processes. The EcoVeg approach was used to develop the International Vegetation Classification (IVC) and various national classifications, which integrate patterns of vegetation growth form, structure, and floristics with ecological and biogeographic drivers at multiple spatial scales, from global formations to local plant communities. The approach remains unique among terrestrial ecological classifications in providing types at these scales. However, as a terrestrial typology, lack of context with respect to freshwater, marine and subterranean realms limited its clarity. Further, growth forms and structure were limited to readily observable features, which excluded important functional traits. The release by the International Union for Conservation of Nature (IUCN) of the Global Ecosystem Typology (GET) presented an opportunity to revisit the EcoVeg approach because GET has a conceptually robust, scalable, and spatially explicit functional approach for all of earth's ecosystems (terrestrial, freshwater, marine, subterranean). Here, we briefly introduce the EcoVeg approach and the GET, and then outline a biome‐based revision to EcoVeg and the IVC that builds on the strengths of GET for global terrestrial types and the IVC for continental to local terrestrial types. The outcome is a revised IVC that we rename the ecosystem‐based International Vegetation Classification (eIVC). As with GET, the eIVC has a conceptual foundation based on realms and transitional realms, but it focuses on the terrestrial and transitional terrestrial (wetland) realms. It then fully implements terrestrial biome concepts across all the upper levels based on the integration of vegetation with global ecosystem processes and properties. Interoperable compatibility with GET is reflected in the fact that 84% of the global ecosystem types are largely equivalent, which facilitates the linkage of GET with the continental to local ecosystem types of the eIVC. The revisions that now form the eIVC will enhance collaborative development of ecosystem types across the globe and provide more robust opportunities for co‐application of the eIVC and GET in the terrestrial realm for management, conservation, and restoration.

Aims The class Crypsietea aculeatae comprises pioneer ephemeral dwarf-graminoid vegetation occurring in periodically flooded saline habitats. Although numerous regional studies have described this vegetation, a unified classification across Europe has been lacking. This study aims to establish a formalized, continent-wide classification at the association level, identify its biogeographical patterns, and assess relationships between species composition and environmental gradients.Location Europe (except Armenia, Azerbaijan, Georgia, and Russia).Methods We compiled a dataset of 2538 vegetation plots from the European Vegetation Archive (EVA), private databases, and literature. A hierarchical expert system was developed using formal definitions of syntaxa based on species cover. Nonmetric multidimensional scaling (NMDS) was applied to evaluate compositional differences and reveal biogeographical patterns. Distance-based redundancy analysis (db-RDA) and unweighted community means of Ellenberg-type indicator values (EIVs) were used to assess environmental drivers.Results We present a revised syntaxonomic framework for the class Crypsietea aculeatae and propose updates to the EuroVegChecklist. One alliance (Cypero-Spergularion marinae) and four associations (Crypsietum aculeatae, Crypsietum schoenoidis, Cyperetum pannonici, and Oxybasio chenopodioidis-Crypsietum aculeatae) were formally defined, with basic descriptions of their species composition, ecological characteristics, and geographical distribution. The main gradients in vegetation variability within the class Crypsietea aculeatae are driven by climatic gradient and edaphic factors, including soil moisture, soil acidity, salinity, and nutrient availability.Conclusions We established the first formal classification of annual vegetation in European saline seasonal wetlands. The syntaxonomic nomenclature was revised, and modifications to the EuroVegChecklist were proposed. The resulting classification system, accompanied by an expert system, enables consistent application in nature conservation and ecological research.

The Natura 2000 (N2K) network of protected areas is one of the main tools for area-based conservation in the European Union (EU), yet its role in preserving plant biodiversity requires better understanding. We examined data kept in the European Vegetation Archive from over 1.2 million vegetation plots and obtained over 14.2 million plant species occurrences. To test the N2K network's representativeness of plant species gamma diversity, we compared the number and percentage of native and conservation priority species in- and outside the N2K network throughout the EU and for individual countries, biogeographical regions, and combinations thereof. We then determined whether N2K sites hosted more species than sites outside the network with the species-area relationship. Overall, almost 90% of the native vascular plant species occurred at least once in the N2K network. Yet, significant variation exists across countries and biogeographical regions-from 0% of species in the Boreal region of Lithuania, to 98% in the Alpine region of Croatia-indicating that local N2K sites are not equally representative of the regional gamma diversity. Nonetheless, the N2K network contains more species than land outside the network when area is taken into account. The planned expansion of the N2K network, as mandated by the European Biodiversity Strategy for 2030, should prioritize areas with currently underrepresented elements of the EU vascular flora.

We report the decisions of the GPN assembly in 2025 regarding previous recommendations of the Committee for Change and Conservation of Names (CCCN) and we discuss three Requests for a binding decision and four nomenclatural Proposals. Recommendations on acceptance or rejection of these Proposals are provided. Taxonomic reference: Euro+Med PlantBase (https://europlusmed.org/) [accessed 14 Nov 2025] Abbreviations: CCCN = Committee for Change and Conservation of Names; GPN = Working Group for Phytosociological Nomenclature; IAVS = International Association for Vegetation Science; ICPN = International Code of Phytosociological Nomenclature, ed. 4; VCS = Vegetation Classification and Survey.

AimForests dominated by non-native trees are becoming increasingly common. However, their impact on biodiversity remains uncertain, with a debate on whether they represent 'green deserts' or secondary habitats for biodiversity. We addressed this question by evaluating the patterns and ecological drivers of taxonomic and functional understory diversity between black pine (Pinus nigra) forests within and outside its native distribution range.LocationEurope.MethodsWe collected a continental database of vegetation plots with full species composition and related functional traits. We compared alpha- and beta-taxonomic (TD) and functional (FD) diversity between understories of P. nigra forests within and outside its native distribution range, and modelled the relative effects of climate, soil conditions, and canopy cover.ResultsWe found similar values of alpha- and beta-TD and -FD in forests within and outside the native range. The response to local and large-scale drivers was also similar, with high canopy cover reducing alpha-TD and alpha-FD but enhancing beta-TD and beta-FD in both forest systems. Soil nutrients enhanced alpha-TD and alpha-FD and decreased beta-FD only in forests within the native range, while drought reduced alpha- and beta-diversities only in forests outside the native range.Main ConclusionsThe same dominant tree species under similar ecological conditions resulted in low diversity differentiation between forests both within and outside P. nigra native range. Nevertheless, understory diversity was sensitive to different ecological drivers, with stronger effects of soil fertility and moisture on forests within and outside native ranges, respectively. These results suggest that P. nigra forests established beyond the species' native range exhibit similar diversity metrics and ecosystem functions as those within its native range. Our findings may be linked to the fact that P. nigra forests outside the native range were placed in the same biogeographical region as the corresponding forest stands within the native range.

This editorial opens the sixth volume of Vegetation Classification and Survey (VCS), a gold open access journal of the International Association for Vegetation Science (IAVS). On occasion of the fifth anniversary of the start of the journal, we provide an analysis of the 119 articles published from 2020 to 2024, focusing on their content, geographic scope, article category and the collection they belong to, if any. For articles that performed a plot-based classification, we provide information on classification approach, plot size, importance value, taxonomic coverage, number of plots, and classification algorithm. We also analyze the bibliometric performance of VCS across the five years and predict a CiteScore of 3.6 and a Journal Impact Factor of 2.7 for 2024 (to be published in 2025). Using the Field-Weighted Citation Impact (FWCI) from the Scopus database, we identified the nine VCS articles published in the first five years that received at least twice as many citations as expected for their age and field. Next we present the four Editors’ Choice papers of 2024, among which Naftal et al. (2024; Vegetation Classification and Survey 5: 127–151) received the Editors’ Award. We conclude that VCS is on the right track, although we would like to encourage the submission of more classification papers based on large plot datasets, as well as methodological papers and comprehensive reviews. Abbreviations: CCCN = Committee for Changes and Conservation of Names; FWCI = Field-Weighted Citation Impact; JIF = Journal Impact Factor; IAVS = International Association for Vegetation Science; VCS = Vegetation Classification and Survey.

During Pleistocene cold stages, European temperate forests were not only restricted to refugia in the southern European peninsulas. Rather, there is increasing evidence for the survival of trees also in isolated patches further north, termed 'northern refugia'. While their existence is undisputed, based on what is known from a handful of tree species, there is very limited knowledge about forest understoreys. Here, we fill this gap by examining the evolutionary histories of three Central European forest understorey species (FUS; Aposeris foetida, Cardamine trifolia, Hacquetia epipactis). To do so, we use a set of exploratory and explicit analyses utilising genomic data and ecological niche models, and interpret these data following a priori defined framework. We identify the northwestern Balkan Peninsula as the primary diversification center for the three species but found additional northern refugia in the Alps, the Carpathians, and the Apennines. Divergence times indicated pre-Last Glacial Maximum (LGM) diversification within each FUS, suggesting persistence of forest islands in Central Europe during Pleistocene cold stages rather than exclusively post-LGM colonisation. We conclude that FUS thrived in scattered northern refugia. This refines our understanding of past forest dynamics and further supports widespread long-term persistence of forest patches in Central Europe during Pleistocene cold stages.

The first comprehensive phytosociological classification of all vegetation types in Europe (EuroVegChecklist; Applied Vegetation Science, 2016, 19, 3-264) contained brief descriptions of each type. However, these descriptions were not standardized and mentioned only the most distinct features of each vegetation type. The practical application of the vegetation classification system could be enhanced if users had the option to select sets of vegetation types based on various combinations of structural, ecological, and biogeographical attributes. Based on a literature review and expert knowledge, we created a new database that assigns standardized categorical attributes of 12 variables to each of the 1106 alliances dominated by vascular plants defined in EuroVegChecklist. These variables include dominant life form, phenological optimum, substrate moisture, substrate reaction, salinity, nutrient status, soil organic matter, vegetation region, elevational vegetation belt, azonality, successional status and naturalness. The new database has the potential to enhance the usefulness of phytosociological classification for researchers and practitioners and to help understand this classification to non-specialists.

We report the decisions made by the Assembly of the Group of Phytosociological Nomenclature (GPN) in 2023 on previous recommendations of the Committee for Change and Conservation of Names (CCCN). Further, we discuss eight Requests for a binding decision and nine nomenclatural Proposals. Recommendations on acceptance or rejection of these Proposals are provided. We recommend the conservation of the following names: Mesobromion erecti (Braun-Blanquet et Moor 1938) Zoller 1954, Galio sylvatici-Carpinetum betuliOberdorfer 1957, Lithospermo-Carpinetum betuliOberdorfer 1957, Nanocyperetalia Klika 1935, IsoetetaliaBraun-Blanquet 1936 and Molinio arundinaceae-Quercetum Neuhäusl et Neuhäuslová-Novotná 1967. Abbreviations: CCCN = Committee for Change and Conservation of Names; GPN = Working Group for Phytosociological Nomenclature; ICPN = International Code of Phytosociological Nomenclature; VCS = Vegetation Classification and Survey.

Pioneer plant communities dominated by therophytes, succulents, bryophytes and lichens on base-rich substrata of the Alysso-Sedion alliance are endangered and highly important for biodiversity protection. This study aims to revise previous syntaxonomic concepts and provide a unified classification of the Alysso-Sedion communities in the northern part of the Carpathian-Pannonian region, Bohemian Massif, western Ukraine, Romania and Moldova. We extracted relev & eacute;s dominated by annuals, succulents, bryophytes, and lichens from the European Vegetation Archive. We also selected nomenclatural types of 12 associations reported within the Alysso-Sedion alliance in the study area. Using a classification expert system, we selected an initial dataset of 10,211 relev & eacute;s of annual and succulent vegetation. We resampled the initial dataset within geographical strata and obtained a dataset of 620 relev & eacute;s, which we classified using the modified TWINSPAN algorithm. The TWINSPAN classi-fication resulted in 19 clusters. We removed 11 clusters interpreted as outliers or non-target vegetation types and interpreted the remaining eight clusters as the associations Alysso petraei-Sedetum hispanici, Alyssetum muralis, Saxifrago tridactylitae-Poetum compressae, Alysso alyssoidis-Sedetum, Aurinio saxatilis-Allietum podolici, Cerastietum pumili, Sedo albi-Allietum montani and Sempervivetum sobo-liferi. The communities are differentiated along the gradients of nutrients, temperature and light availability. We provide the first unified international classification of the Alysso-Sedion alliance that includes Ukrainian and Moldovian communities. This classification largely corresponds to the existingclassifications published in the vegetation monographs of Austria, the Czech Republic, Slovakia, Poland, Romania, Ukraine and Moldova.

This manuscript provides a review of the phytosociological nomenclature of the European syntaxa included in the classes Ammophiletea arundinaceae, Honckenyo peploidis-Elymetea arenarii, and Koelerio glaucae-Corynephoretea canescentis. The nomenclature has been refined and updated following the 4th edition of the International Code of Phytosociological Nomenclature (ICPN). In the Appendix, we submit two proposals (37, 38) to conserve the names Ammophilion arundinaceaeBraun-Blanquet 1933 and Medicagini marinae-Ammophiletum arundinaceaeBraun-Blanquet 1933. Taxonomic reference: see references in the main text. Syntaxonomic reference: see references in the main text. Abbreviations: EVCC = European Vegetation Classification Committee; ICPN = 4th edition of the International Code of Phytosociological Nomenclature (Theurillat et al. 2021).

Aims: We introduce ReSurveyEurope - a new data source of resurveyed vegetation plots in Europe, compiled by a collaborative network of vegetation scientists. We describe the scope of this initiative, provide an overview of currently available data, governance, data contribution rules, and accessibility. In addition, we outline further steps, including potential research questions. Results: ReSurveyEurope includes resurveyed vegetation plots from all habitats. Version 1.0 of ReSurveyEurope contains 283,135 observations (i.e., individual surveys of each plot) from 79,190 plots sampled in 449 independent resurvey projects. Of these, 62,139 (78%) are permanent plots, that is, marked in situ, or located with GPS, which allow for high spatial accuracy in resurvey. The remaining 17,051 (22%) plots are from studies in which plots from the initial survey could not be exactly relocated. Four data sets, which together account for 28,470 (36%) plots, provide only presence/absence information on plant species, while the remaining 50,720 (64%) plots contain abundance information (e.g., percentage cover or cover-abundance classes such as variants of the Braun-Blanquet scale). The oldest plots were sampled in 1911 in the Swiss Alps, while most plots were sampled between 1950 and 2020. Conclusions: ReSurveyEurope is a new resource to address a wide range of research questions on fine-scale changes in European vegetation. The initiative 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). ReSurvey:Europe data are ready for use, and proposals for analyses of the data set can be submitted at any time to the coordinators. Still, further data contributions are highly welcome.

AimWe aim to refine the definition of peri-Carpathian forest-steppe grasslands, provide an updated distribution map, identify consensus indicator species and summarise data on their extreme species richness.LocationEast-Central Europe (Czech Republic, Austria, Slovakia, Hungary, Romania, Ukraine).TaxonVascular plants.MethodsA total of 127 vegetation plots from large vegetation databases and field sampling were classified as the Brachypodio-Molinietum association based on two criteria: (1) the existing formal definition and (2) a threshold of consensus indicator species derived from a literature review. The plots were mapped, and their basic habitat conditions were characterised. Habitat affiliations of consensus indicator species were expressed using the diagnostic species lists in the EuroVegChecklist. Maximum species richness values were extracted from the plot data and summarised.ResultsPeri-Carpathian forest-steppe grasslands of the Brachypodio-Molinietum association have been recorded across a large area of East-Central Europe, particularly in the lower to middle altitudes of the Western and Eastern Carpathians and their foothills and adjacent regions. These grasslands typically occur in moderately warm, relatively precipitation-rich regions with deep soils, primarily on plateaus and gentle slopes of up to 10 degrees, developed predominantly over less consolidated Mesozoic and Tertiary sedimentary rocks. We identified 60 consensus indicator species, mostly species of forest-steppe habitats, with species of mesic grasslands also well represented. The current maxima of vascular plant species richness exceed 110 species per 10-16 m2. These maxima have been recorded in three regions: the Prut-Siret Interfluve in western Ukraine, the NW Transylvanian Basin in Romania and the White Carpathian Mts in the Czech Republic.Main ConclusionsThe extremely species-rich peri-Carpathian forest-steppe grasslands are confined to a geographically well-defined area of East-Central Europe. The observed fine-scale species richness of vascular plants is currently the highest known in the world. In addition to similar habitat conditions, the presence of an ancient forest-steppe species pool appears to be a prerequisite for such extreme species richness. Recent paleoecological evidence supports this hypothesis.