Kiril Vassilev

Bulgarian Academy of Sciences | BAS · Flora and Vegetation

Aims: Developing a hierarchical classification system for classes, orders and alliances of the diverse dry grasslands of the Central and Eastern Balkan Peninsula and translating this into an electronic expert system (ES) for the automatic assignment of plots. Location: Serbia, Kosovo, North Macedonia, Bulgaria and northern Greece. Methods: We extra...

The study is focused on the study of forest habitats of Svoge Municipality, situated in the western part of the country. The total area of Svoge Municipality is 868 km 2. 134 relevés were collected during the period of 2015-2019, following the Braun-Blanquet approach and 445 field points were verified, as well. As a result, nine forest habitat type...

Class Mulgedio-Aconitetea comprises plant communities that develop primarily in the upper montane to subalpine vegetation belts. It is vegetation where tall herb species (forbs, ferns, grasses) occur dominantly; in the Balkans, it was studied only marginally. In this article, based on floristic composition we assess two questios: (1) how diverse is...

Aldrovanda vesiculosa is an endangered aquatic species in Romania which grows in shallow waters where competition with other aquatic species is limited or absent. A comprehensive overview of the species’ distribution and habitat preferences in Romania is currently lacking. In this context, this study aimed to update the distribution and habitat pre...

Iris brandzae is one of the most threatened plant species in Romania. The current distribution of this species in Romania is very fragmented, and the population size has been reduced in the last 30 years. Information on the habitat preferences of the species has not been summarized yet. In this context, this study aimed to identify the habitat pref...

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 th...

The class Montio-Cardaminetea includes vegetation of springs with constant water flow. These habitats, which function as islands for highly specialized and sensitive biota, are endangered by ongoing landscape and climatic changes. Although a harmonized classification into vegetation units is necessary for effective habitat conservation, there is cu...

Paracossulus thrips (Hübner, 1818) is a protected species in Europe through the Council Directive 92/43/ EEC. Pupal exuviae belonging to this species were found at each of two patches at Chepan Mt. (Western Bulgaria) characterised by Phlomis tuberosa L. being a dominant plant species. This is the first record of this host plant of P. thrips in Bulg...

The current study aims at revealing the forest habitat diversity of Godech Municipality, according to the EUNIS habitat classification. Initial data was collected from the Ministry of Environment and Water and the Forestry Management Plans. Subsequently, 418 vegetation plots (relevés) and 3422 verification points were collected during the fieldwork...

The paper presents the results of a study of the plant communities of Ramonda serbica, primarily intended to increase knowledge of their species and syntaxonomic diversity. The dataset included 204 vegetation plots (relevés) of the two Balkan Ramondas (R. serbica and R. nathaliae), 174 digitised from published literature sources and 30 new ones fro...

The study is focused on the investigation of the forest habitats and the vegetation of Dragoman municipality, located in western Bulgaria. Following the Braun-Blanquet approach, 212 relev´es were collected in 2019 and 1054 field points were verified, as well. As a result, eight forest habitat types included in Directive 92/43/EEC were identified. T...

Aims Oak–hornbeam forests and related vegetation types (phytosociological order Carpinetalia betuli ) are widespread in temperate western Eurasia. However, their national classification systems are poorly compatible, and a broad‐scale classification based on numerical analyses is lacking. Therefore, we aimed to establish a unified formalized classi...

Global patterns of regional (gamma) plant diversity are relatively well known, but whether these patterns hold for local communities, and the dependence on spatial grain, remain controversial. Using data on 170,272 georeferenced local plant assemblages, we created global maps of alpha diversity (local species richness) for vascular plants at three...

The investigated territory is located in the Western part of Bulgaria. The aim of the presented research is to reveal the diversity of grassland habitats in Godech Municipality. Following the Braun-Blanquet approach, 418 relevés were collected during the 2019-2020 field seasons and the grassland habitats were verified at 3422 field points, as well....

The importance of environmental difference among sites and dispersal limitations of species to the explanation of diversity differs among biological systems and geographical regions. We hypothesized that climate and then dispersal limitation will predominantly explain the similarity of alpine vegetation at increasing distances between pairs of regi...

The current study aims to uncover the forest habitat diversity of Breznik Municipality, following the EUNIS Classification. Initial data was collected from the Ministry of Environment and Water and the Forestry Management Plans. Forest habitat polygons were spatially processed with the use of the ArcGIS 10.8.1 software package. Field studies were p...

Class Polygono-Poetea annuae Rivas-Mart. 1975 includes therophyte-rich vegetation on trampled habitats. The study presents the first analysis of the syntaxonomy of this class and its ecology in Bulgaria. One hundred seventy-five relevés from this class were collected and stored in the Balkan Vegetation Database during 2017–2020. Numerical classific...

Aim The first comprehensive checklist of European phytosociological alliances, orders and classes (EuroVegChecklist) was published by Mucina et al. (2016, Applied Vegetation Science , 19 (Suppl. 1), 3–264). However, this checklist did not contain detailed information on the distribution of individual vegetation types. Here we provide the first maps...

This work represents the first study of the floristic diversity on Bulgaria’s ancient mounds. The objective of this research was to assess the importance of the mounds for the preservation of the native vascular and cryptogam flora. Our sampling design included 111 ancient mounds distributed throughout the country. We recorded a total of 1059 vascu...

In this study the phytocoenoses of Petasites albus, P. hybridus and P. kablikianus were investigated on the territory of Bulgaria and Romania. Numerical classification and ordination were performed by PC-ORD and JUICE software packages. Diagnostic species were determined by calculating the Phi-coefficient. Three associations of the Petasition offic...

The current paper represents a preliminary investigation of habitats on the territory of Godech Municipality, located in Western Bulgaria. It is based on the information, presented by the Ministry of Environment and Waters and the mapping of NATURA 2000 sites of Western Balkan Range and Forebalkan (BG0001040) and Dragoman (BG0000322). Data is proce...

This paper comprises an overview of the riverine, swamp, floodplain forests and scrub throughout the continent. The team of researchers from various European countries has considered most of the forest habitats from the Canary Islands to European Russia. It was a difficult task to gather all the knowledge about this type of vegetation across the...

Aim: The steppe grasslands of eastern Central Europe are exceptionally species-rich and valuable from a nature conservation point of view. However, their historical biogeography is still poorly understood. Here we use the regional diversity of habitat specialists and chloroplast DNA data to investigate potential long-term refugia of steppe species...

Aim: To analyse the biogeographic patterns of Temperate Deciduous Forests (TDFs) in Western Eurasia based on different life-forms and forests layers and explore their relationships with the current climate, Last Glacial Maximum (LGM) climate and topography. Location: Western Eurasia. Taxon: Vascular plants. Methods: We delimited nine regions encomp...

Aim To analyse the biogeographic patterns of Temperate Deciduous Forests (TDFs) in Western Eurasia based on different life-forms and forests layers and explore their relationships with the current climate, Last Glacial Maximum (LGM) climate and topography. Location Western Eurasia. Taxon Vascular plants. Methods We delimited nine regions encompa...

Assessing biodiversity status and trends in plant communities is critical for understanding, quantifying and predicting the effects of global change on ecosystems. Vegetation plots record the occurrence or abundance of all plant species co‐occurring within delimited local areas. This allows species absences to be inferred, information seldom provid...

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...

The current research focuses on the investigation of shrubland vegetation in Dragoman municipality. The study is motivated by the willingness of the authors to check the shrubland habitats’ territorial extent and their importance to ecosystem processes, following the increased degree of succession over the last three decades. On the other hand, gov...

Aim The number of naturalized (i.e. established) alien species has increased rapidly over recent centuries. Given the differences in environmental tolerances among species, little is known about what factors determine the extent to which the observed size of the naturalized range of a species and hence the extent to which the observed richness of n...

Questions: Which environmental factors influence fine-grain beta diversity of vegetation and do they vary among taxonomic groups? Location: Palaearctic biogeographic realm. Methods: We extracted 4,654 nested-plot series with at least four different grain sizes between 0.0001 m² and 1,024 m² from the GrassPlot database, covering a wide range of di...

This study aims at mapping and investigating the grassland habitats, defined by Directive 92/43/EEC, on the territory of Dragoman Municipality, Bulgaria. The municipality is located in the western part of the country and is characterized by semi-mountainous terrains and temperate climate. During the fieldwork in 2019 and 2020, 212 relevés were coll...

Significance Invasive alien species pose major threats to biodiversity and ecosystems. However, identifying drivers of invasion success has been challenging, in part because species can achieve invasiveness in different ways, each corresponding to different aspects of demographics and distribution. Employing a multidimensional perspective of invasi...

Class Artemisietea vulgaris includes thermophilic and (sub)xerophytic ruderal vegetation, which consists mostly of biannual and perennial seminitrophilous to nitrophilous species, widely distributed in the temperate and the submediterranean zones of Europe. The study presents a comprehensive review of its ecology and syntaxоnomy on the territory of...

Aims Biodiversity is traditionally studied mostly at the species level, but biogeographical and macroecological studies at higher taxonomic levels can provide valuable insights into the evolutionary processes at large spatial scales. Our aim was to assess the representation of vascular plant families within different vegetation formations across Eu...

Conceptual figure summarizing our hypotheses how different drivers could influence fine-grain β-diversity via changing mean occupancy of species, based on the findings of our study and theoretical considerations. Fine-grain β-diversity (and likewise for larger grain sizes) is mathematically linked to mean occupancy, which can be decomposed into (i)...

Aim Plant functional traits summarize the main variability in plant form and function across taxa and biomes. We assess whether geographic range size, climatic niche size, and local abundance of plants can be predicted by sets of traits (trait syndromes) or are driven by single traits. Location Eurasia Methods Species distribution maps were extrac...

Questions The human‐related spread of alien plants has serious environmental and socioeconomic impacts. Therefore, it is important to know which habitats are most threatened by invasion and why. We studied a wide range of European grasslands to assess: (a) which alien species are the most successful invaders in grasslands; (b) how invasion levels d...

Aim Alpine ecosystems differ in area, macroenvironment and biogeographical history across the Earth, but the relationship between these factors and plant species richness is still unexplored. Here, we assess the global patterns of plant species richness in alpine ecosystems and their association with environmental, geographical and historical facto...

Questions European woodlands harbor at least 386 alien plant species but the factors driving local invasions remain unknown. By using a large vegetation‐plot database, we asked how local richness and abundance of alien species vary by regions, elevation, climate, soil properties, human disturbance, and habitat types. Location Western, Central and S...

Aim Alpine habitats support unique biodiversity confined to high‐elevation areas in the current interglacial. Plant diversity in these habitats may respond to area, environment, connectivity and isolation, yet these factors have been rarely evaluated in concert. Here we investigate major determinants of regional species pools in alpine grasslands,...

Questions What are the functional trade‐offs of vascular plant species in global alpine ecosystems? How is functional variation related to vegetation zones, climatic groups and biogeographic realms? What is the relative contribution of macroclimate and evolutionary history in shaping the functional variation of alpine plant communities? Location G...

Questions: Studying dry grasslands in a previously unexplored region, we asked: (i) Which environmental factors drive the diversity patterns in vegetation? (ii) Are taxonomic groups (vascular plants, bryophytes, lichens) and functional vascular plant groups differently affected? (iii) How is fine-grain beta diversity affected by environmental drive...

Aims (a) To determine the contribution of current macro‐environmental factors in explaining the phylogenetic structure of European forest vegetation, (b) to map and describe spatial patterns in their phylogenetic structure and (c) to examine which lineages are the most important contributors to phylogenetic clustering and whether their contribution...

Melliferous plants are key to the ecosystem pollination service. The melliferous plants are under strong anthropogenic pressure in the conditions of intensive agriculture and modern climate changes in southern Europe. The study is aimed at identifying and spatial distribution of honey plants species in traditional agricultural areas of northern Bul...

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, Monte...

Aims The effect of biogeographical processes on the spatial turnover component of beta‐diversity over large spatial extents remains scarcely understood. Here, we aim at disentangling the roles of environmental and historical factors on plant taxonomic and phylogenetic turnover, while controlling for the effects of species richness and rarity. Loca...

Alibotush Reserve is located in Slavyanka Mountain, Southwestern Bulgaria, near the state border with Greece. It was established as protected area in 1951 and currently covers 1638.12 ha, which is about 25% of the Bulgarian territory of the mountain. It has the strictest protection regime according to Bulgaria’s national legislation and corresponds...

Aim The EUNIS Habitat Classification is a widely used reference framework for European habitat types (habitats), but it lacks formal definitions of individual habitats that would enable their unequivocal identification. Our goal was to develop a tool for assigning vegetation‐plot records to the habitats of the EUNIS system, use it to classify a Eur...

This study deals with the diversity of forest vegetation in the Slivenska Mountain (Eastern Stara planina) and presents a contemporary classification scheme for the identified syntaxa. A total of 137 relevés were collected and analyzed using specialized software (JUICE 7.0 and PC-ORD Version 4). As a result, forest vegetation is classified into 10...

The present investigation aims to uncover the landscape diversity in Dragoman Municipality, as well as the ecosystem types, which are representative for the territory. The interest towards this geographical area roots in its close proximity to the capital city of Sofia and the ongoing road works for the establishment of the "Europe" Motorway. It al...

Aim: A fundamental question in macroecology centres around understanding the relationship between species’ local abundance and their distribution in geographical and climatic space (i.e. the multi-dimensional climatic space or climatic niche). Here, we tested three macroecological hypotheses that link local abundance to the following range properti...

Aim: A fundamental question in macroecology centres around understanding the relationship between species’ local abundance and their distribution in geographical and climatic space (i.e. the multi-dimensional climatic space or climatic niche). Here, we tested three macroecological hypotheses that link local abundance to the following range properti...

The paper presents a comprehensive numerical analysis of vegetation within the class Loiseleurio-Vaccinietea Eggler ex Schubert 1960 in Southeastern Carpathians (Romanian Carpathians), specifically the cryophilous dwarf-shrub heathlands on windswept slopes and edges and acidophilous mesophilous dwarf-shrub communities in subalpine and alpine belts....

This article deals with the changes in Bulgarian culture after the fall of the Communist regime in Bulgaria in 1989. The first sections sketch the state of the Bulgarian culture and society during the later years of the communism. They describe the change in official ideology, i.e. the return to nationalism. The controversial role of the Communist...

Studies on the impact of agricultural practices on plant diversity provide an important information for policy makers and conservation of the environment. The aim of the present work was to evaluate wild plant diversity across the agroecosystems in two contrasting regions of Bulgaria; Pazardzhik-Plovdiv (representing agroecosystems in the lowlands)...

This study deals with the diversity of forest vegetation in the Slivenska Mountain (Eastern Stara planina) and presents a contemporary classification scheme for the identified syntaxa. A total of 137 relevés were collected and analyzed using specialized software (JUICE 7.0 and PC-ORD Version 4). As a result, forest vegetation is classified into 10...

Steppe grasslands represent important refuges for rare species in the Pannonian region of eastern Central Europe. Nevertheless, little is known about their regional continuity and potential (post)glacial in-situ survival. Biogeographical studies assume potential source areas for the postglacial (re)colonisation of the Pannonian region in the Wester...

Mantle vegetation includes plant communities dominated mostly by shrubs and occurs in habitats where the typical tree layers meet difficulties to evolve. This study was conducted in three areas of Bulgaria – Western Balkan Range, Western Sredna Gora Mt. and the Fore-Balkan. Numerical classification and ordination were performed by PC-ORD and JUICE...

Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research sp...

Aim Biodiversity databases are valuable resources for understanding plant species distributions and dynamics, but they may insufficiently represent the actual geographic distribution and climatic niches of species. Here we propose and test a method to assess sampling coverage of species distribution in biodiversity databases in geographic and clima...

Supporting information for the article Alpha diversity of vascular plants in European forests Article DOI: 10.1111/jbi.13624 Read-only version: https://rdcu.be/bGrNA

Spatial distribution of forest vegetation plots, ranging from 100 to 1,000 m2 in plot size, used as an input dataset for modelling alpha‐diversity patterns (n = 73,134). The colours indicate the total number of vascular plant species recorded per plot (i.e., alpha diversity). For this visualization, alpha‐diversity values displayed on the map were...

Integrated relative importance of predictor variables for explaining alpha‐diversity patterns for all forests and for each forest type separately. The black part of the bars indicates the contribution of the “Mean decrease in node impurity” to the integrated relative importance, while the grey part indicates the contribution of the “Mean decrease i...

Effects of the three top‐ranked predictor variables on alpha diversity for all forests and for each forest type separately (partial dependence plots). The integrated importance scores are shown in parentheses. AET, actual evapotranspiration; PET, potential evapotranspiration; VRM, vector ruggedness measure. The effects of the lower‐ranked predictor...