The Balkan Vegetation Database (BVD; GIVD ID: EU-00-019) is a regional database, which was established in 2014. It comprises phytosociological relevés covering various vegetation types from nine countries of the Balkan Peninsula (Albania – 153 relevés, Bosnia and Herzegovina – 1715, Bulgaria – 12,282, Greece – 465, Croatia – 69, Kosovo – 493, Montenegro – 440, North Macedonia – 13 and Serbia – 2677). Currently, it contains 18,306 relevés (compared to 9.580 in 2016), and most of them (82.8%) are geo-referenced. The database includes both digitized relevés from the literature (65.6%) and unpublished data (34.5%). Plot size is available for 84.7% of all relevés. During the last four years some “header data information” was improved e.g. elevation (now available for 83.4% of all relevés), aspect (67.7%), slope (66%), total cover of vegetation (54.3%), cover of tree, shrub, herb, bryophyte and lichen layers (27.1%, 20.1%, 40.2%, 11.5% and 2.1%), respectively. Data access is either semi-restricted (65.6%) or restricted (34.4%). Most relevés (84.6%) are classified to syntaxa of different levels. The database has been used for numerous studies with various objectives from floristic, vegetation and habitat-related topics, to macroecological studies at the local, regional, national, continental and global levels. During the last four years, BVD data were requested from 111 different projects via the EVA and sPlot databases.

Abstract. Water resources and associated ecosystems are becoming highly endangered due to ongoing global environmental changes. Spatial ecological modelling is a promising toolbox for understanding the past, present and future distribution and diversity patterns in groundwater-dependent ecosystems, such as fens, springs, streams, reed beds or wet grasslands. Still, the lack of detailed water chemistry maps prevents the use of reasonable models to be applied on continental and global scales. Being major determinants of biological composition and diversity of groundwater-dependent ecosystems, groundwater pH and calcium are of utmost importance. Here we developed an up-to-date European map of groundwater pH and Ca, based on 7577 measurements of near-surface groundwater pH and calcium distributed across Europe. In comparison to the existing European groundwater maps, we included several times more sites, especially in the regions rich in spring and fen habitats, and filled the apparent gaps in eastern and southeastern Europe. We used random forest models and regression kriging to create continuous maps of water pH and calcium at the continental scale, which is freely available also as a raster map (Hájek et al., 2020b; https://doi.org/10.5281/zenodo.4139912). Lithology had a higher importance than climate for both pH and calcium. The previously recognised latitudinal and altitudinal gradients were rediscovered with much refined regional patterns, as associated with bedrock variation. For ecological models of distribution and diversity of many terrestrial ecosystems, our new map based on field groundwater measurements is more suitable than maps of soil pH, which mirror not only bedrock chemistry but also vegetation-dependent soil processes.

This paper presents new records and noteworthy data on the following taxa in SE Europe and adjacent regions: the diatom alga Eunotia boreoalpina; the saprotrophic fungus Clitocybe truncicola; the liverwort Haplomitrium hookeri; the moss Leptodon smithii: the monocots Epipactis purpurata, Stipa tirsa, Typha laxmannii and T. shuttleworthii; and the dicots Krascheninnikovia ceratoides, Polygonum albanicum and Sorbus latifolia.