Aims: Understanding fine‐grain diversity patterns across large spatial extents is fundamental for macroecological research and biodiversity conservation. Using the GrassPlot database, we provide benchmarks of fine‐grain richness values of Palaearctic open habitats for vascular plants, bryophytes, lichens and complete vegetation (i.e., the sum of the former three groups).Location: Palaearctic biogeographic realm.Methods: We used 126,524 plots of eight standard grain sizes from the GrassPlot database: 0.0001, 0.001, 0.01, 0.1, 1, 10, 100 and 1,000 m² and calculated the mean richness and standard deviations, as well as maximum, minimum, median, and first and third quartiles for each combination of grain size, taxonomic group, biome, region, vegetation type and phytosociological class.Results: Patterns of plant diversity in vegetation types and biomes differ across grain sizes and taxonomic groups. Overall, secondary (mostly semi‐natural) grasslands and natural grasslands are the richest vegetation type. The open‐access file ”GrassPlot Diversity Benchmarks” and the web tool “GrassPlot Diversity Explorer” are now available online (https://edgg.org/databases/GrasslandDiversityExplorer) and provide more insights into species richness patterns in the Palaearctic open habitats.Conclusions: The GrassPlot Diversity Benchmarks provide high‐quality data on species richness in open habitat types across the Palaearctic. These benchmark data can be used in vegetation ecology, macroecology, biodiversity conservation and data quality checking. While the amount of data in the underlying GrassPlot database and their spatial coverage are smaller than in other extensive vegetation‐plot databases, species recordings in GrassPlot are on average more complete, making it a valuable complementary data source in macroecology.

Habitat monitoring in Europe is regulated by Article 17 of the Habitats Directive, which suggests the use of typical species to habitat conservation status. Yet, the Directive uses the term “typical” species but does not provide a definition, either for its use in reporting or for its use in impact assessments. To address the issue, an online workshop was organized by the Italian Society for Vegetation Science (SISV) to shed light on the diversity of perspectives regarding the different concepts of typical species, and to discuss the possible implications for habitat monitoring. To this aim, we inquired 73 people with a very different degree of expertise in the field of vegetation science by means of a tailored survey composed of six questions. We analysed the data using Pearson's Chi-squared test to verify that the answers diverged from a random distribution and checked the effect of the degree of experience of the surveyees on the results. We found that most of the surveyees agreed on the use of the phytosociological method for habitat monitoring and of the diagnostic and characteristic species to evaluate the structural and functional conservation status of habitats. With this contribution, we shed light on the meaning of “typical” species in the context of habitat monitoring.

Trait‐based ecology has already revealed main independent axes of trait variation defining trait spaces that summarize plant adaptive strategies, but often ignoring intraspecific trait variability (ITV). By using empirical ITV‐level data for two independent dimensions of leaf form and function and 167 species across five habitat types (coastal dunes, forests, grasslands, heathlands, wetlands) in the Italian peninsula, we found that ITV: (i) rotated the axes of trait variation that define the trait space; (ii) increased the variance explained by these axes and (iii) affected the functional structure of the target trait space. However, the magnitude of these effects was rather small and depended on the trait and habitat type. Our results reinforce the idea that ITV is context‐dependent, calling for careful extrapolations of ITV patterns across traits and spatial scales. Importantly, our study provides a framework that can be used to start integrating ITV into trait space analyses.

The recent Landscape Plan of Tuscany Region pays particular attention towards the floodplain woods, for their conservation concern, landscape, and historical importance. The floodplain forest vegetation is defined as the natural and semi-natural wood vegetation located close to the rivers and submerged only during exceptional flooding. We gathered 180 both published and unpublished relevés coming from Tuscany and carried out in floodplain woods, where Alnus glutinosa, Fraxinus angustifolia subsp. oxycarpa, Quercus robur, Ulmus minor, Carpinus betulus, Populus nigra, P. alba and Salix alba were dominant, alone or in consociation with each other. On this dataset we performed a multivariate analysis, and the resulting groups were characterized by several points of view: floristic, ecological, chorological, by mean of diagnostic species, with the use of EIV. Moreover, their distribution in Tuscany was better defined. According to our results, six associations were found to be present in Tuscany. Thereby, one new association and three new subassociations were proposed. The syntaxonomic arrangement above the association level was discussed, with particular attention to the Italian Fraxinus angustifolia subsp. oxycarpa-rich communities. Finally, a comparison with the Annex I habitat types (sensu Directive 92/43/EEC) was carried out.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions of taxa in the genera Bunias, Calocedrus, Calycanthus, Celosia, Clerodendrum, Convolvulus, Crassula, Cyclamen, Datura, Dicliptera, Eragrostis, Erigeron, Gamochaeta, Gazania, Impatiens, Kolkwitzia, Leucaena, Ludwigia, Medicago, Muscari, Nigella, Oenothera, Opuntia, Paulownia, Petroselinum, Phyllostachys, Physalis, Pseudosasa, Quercus, Reynoutria, Roldana, Saccharum, Sedum, Semiarundinaria, Senecio, Sisyrinchium, Solanum, Sporobolus, Tulipa, Vachellia, Verbena, and Youngia. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

Aim: Ecological communities are assembled by regional and local processes. These processes select species through their traits, which are tied to species' evolutionary history. A multifaceted approach, encompassing taxonomic, functional and phylogenetic diversity can thus help us to better understand community assembly. We asked what the relative importance of geography, climate and soil parameters is in driving taxonomic, functional and phylogenetic diversities at local (alpha) and larger scales (beta diversity).Location: Atlantic Europe.Taxon: Plant communities of Violion caninae grasslands.Methods: Alpha and beta taxonomic, functional and phylogenetic diversities were calculated for 153 sites. Traits were obtained from the LEDA database and phylogeny from Daphne. We summarized climatic (CHELSA database) and soil variables using principal component analysis (PCA), and geographical distance using Moran's Eigenvector Maps (MEMs). To assess the importance of environment and space on all three facets, we performed redundancy and distance‐based redundancy analyses for alpha and beta diversity, respectively, using the PCA and MEM axes as predictors.Results: Compared to alpha diversity, beta diversity was relatively high in taxonomic diversity, but very low in functional and phylogenetic diversity. Geography and climate were relatively more important at larger scales, whereas soil conditions acted more strongly at the local scales, with alpha diversity of all facets decreasing towards richer and acidic soils.Main Conclusions: Considering multiple biodiversity facets along environmental and spatial gradients enables advancing both theoretical and applied aspects of community assembly. Accordingly, the observed turnover across the study area was mediated by species that share similar suites of traits and evolutionary history. Towards richer and acidic soils, exclusion of weaker competitors was an important filter at local scales. In summary, assessing multiple biodiversity facets and broad scale environmental gradients is key to understand the relative importance of multi‐scale processes driving the community assembly of European grasslands.