Numeric syntaxonomical analysis of communities of the Molinia caerulea complex in Southwestern of Ukraine

The aims of the paper are: i) to establish the coenotic affinity of each species of the Molinia caerulea complex in the southwest of Ukraine, ii) to present the results of a comparative analysis of the syntaxa in which include Molinia, iii) to explain possible reasons for the expansion of Molinia caerulea in the studied area. The study area ranges from the basins of the Upper Prut River to the Upper Siret River in Ukraine. To determine the coenotical affinity of the studied species, 134 relevés were analysed. The data analysis was carried out using the Modified TWINSPAN algorithm provided by the JUICE software. Ecological features of the communities were analyzed by means of a DCA-ordination and phytoindication assessment. It was revealed that in the studied region the species of the Molinia caerulea complex are characterized by a relatively wide coenotic and ecological range and that they can be attributed to different communities of 4 vegetation classes: Molinio-Arrhenatheretea (Polygono bistortae-Trisetion flavescentis, Molinion cearuleae, Arrhenatherion elatioris alliances), Festuco-Brometea (Bromion erecti alliance), Mulgedio-Aconitetea (Calamagrostion villosae alliance), Oxycocco-Sphagnetea (Sphagnion magellanici alliance). This paper presents the results of the floristic composition analyses outlines some ecological peculiarities and discusses the conservational values of the identified syntaxa.

Impatiens glandulifera (Balsaminaceae) in Ukraine: its current distribution, ecological and coenotic features

Data on the spontaneous distribution (529 sites) of Impatiens glandulifera in the territory of Ukraine have been collected and studied comprehensively. I. glandulifera invades plant communities of the Phragmito-Magnocaricetea class (1 alliance), Salicetea purpureae (1 association), Alnetea glutinosae (1 association), Robinietea (2 associations), and Epilobietea angustifolii (2 associations). The species phytoindicative assessment, which considered 12 ecological factors, revealed that in its secondary distribution range I. glandulifera shows charactericstics of a stenotopic hygromesophyte, subacidophile and is a semi-eutrophic species. In the studied areas, the environmental niche of I. glandulifera is limited mainly by soil water response (Hd) and saline (Sl) regimes, and soil carbonate content. A thermal regime (Tm) response of the species to an increase in the average annual air temperature by 1, 2, and 30С has been predicted. A temperature increase of 20С could, lead to a critical shift in the values of soil acidity (Rc) and salinity regimes (Sl) that might cause a decline of the species’ potential niches in the studied area. The obtained data have the potential to be useful in limiting the spread of I. glandulifera into new territories and reducing its transforming effect in plant communities of river valley corridors

Benchmarking plant diversity of Palaearctic grasslands and other open habitats

Abstract 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