A syntaxonomical synthesis of calcicolous forests dominated by Fagus sylvatica (Cephalanthero-Fagenion suballiance) in the Czech Republic was carried out using the Braun-Blanquet approach. Relevés included in the analyses were selected following formalized approach by using an expert-delimited group of 38 calcicolous and/or xerothermophilous species. Only one association Cephalanthero-Fagetum was distinguished, which usually occurs on limestone, calcareous sandstone and calcareous sandy marlite; however, can be found also on base-rich siliceous bedrock (e.g. basalt, phonolite). Based on TWINSPAN analysis, three subassociations were recognized within the Cephalanthero-Fagetum: (i) Cephalanthero-Fagetum seslerietosum caeruleae on shallow rocky soils with frequent dominance of Sesleria caerulea and presence of petrophytes, (ii) Cephalanthero-Fagetum typicum on dry, shallow soils with a significant presence of light-demanding, thermophilous, and calcicolous species, and (iii) Cephalanthero-Fagetum actaeetosum spicatae on deeper, sufficiently moist soils with an abundance of mesophilous, nitrophilous and acidophilous species. The name Cephalanthero-Fagetum actaeetosum spicatae is a new nomenclatural combination. The relationships between Cephalanthero-Fagetum and similar forest vegetation types containing xerothermophilous and/or calcicolous species in the Czech Republic are discussed. The main gradients in species composition of Cephalanthero-Fagetum subassociations were revealed by gradient analysis. The Ellenberg indicator values, altitude, slope, and ‘southness’ were used to interpret these gradients. Using unconstrained ordination analysis (DCA) the syntaxonomical interpretation indicated three relatively distinct groups. Moreover, further DCA analysis revealed the well-defined position of Cephalanthero-Fagetum within Czech beech forests. The results of the above delimitation of Cephalanthero-Fagetum were compared with the results based on Cocktail-defined species groups improved by similarity-based assignment of relevés (using frequency-positive fidelity index). When the Cocktail-based formulas for beech forests were applied to the relevés selected by our 38-species diagnostic group, the correspondence between these two approaches was only 36%. However, at the lower subassociation level, the highest correspondence occurred for Cephalanthero-Fagetum seslerietosum (84%). The reason for this high correspondence is that the species composition includes many specialists (i.e. good diagnostic species) and it occurs at the end of an ecological gradient. To sum up, it is possible to define vegetation units accurately using strict formulas, as opposed to the less rigorous ‘soft’ traditional approach. However, both approaches fail when defining central units.
A syntaxonomical revision of dry grasslands of the alliances Bromo pannonici-Festucion pallentis, Festucion valesiacae and Koelerio-Phleion phleoidis (class Festuco-Brometea) in the natural biogeographical region of the Western Carpathians and northern Pannonian Basin is presented. A geographically stratified data set of 2686 relevés from the south-eastern Czech Republic, northeastern Austria, Slovakia and northern Hungary was divided into 25 clusters using a modified TWINSPAN algorithm. The proposed classification simplifies and unifies the previous syntaxonomical systems, which differ in these four countries. Main environmental gradients responsible for variation in species composition of theses grasslands were revealed by detrended correspondence analysis and interpreted using indicator values. The major pattern of variation reflects soil nutrient availability and moisture, which are negatively correlated with soil reaction.
A formalized classification of Czech thermophilous oak forest vegetation is presented. It is based on the Cocktail algorithm, including the formulation of a set of explicit definitions of vegetation units that are used for unequivocal assignment of relevés to defined vegetation types. Eight out of 10 traditionally distinguished associations of thermophilous oak forests were formally defined: Bohemian warm and dry oak forest (Lathyro versicoloris-Quercetum pubescentis), Moravian warm and dry oak forest (Pruno mahaleb-Quercetum pubescentis), dry-mesic oak forest on basic rocky substrates (Corno-Quercetum), dry-mesic oak forest on acidic substrates (Sorbo torminalis-Quercetum), Moravian dry oak forest on acidic substrates (Genisto pilosae-Quercetum petraeae), dry-mesic oak forest on heavy soils (Potentillo albae-Quercetum), dry-mesic oak forest on sandy soils (Carici fritschii-Quercetum roboris) and dry oak forest on loess (Quercetum pubescenti-roboris). The specific features of Cocktail classifications are discussed. The complementarity of the traditional, imperfectly formalized classifications and modern formalized classifications is stressed.
Vegetation with species of Utricularia and that dominated by Eleocharis quinqueflora, which occupy the same habitats. was studied in minerotrophic mires and oligotrophic wetlands associated with ponds. Relative towater and soil chemistry, the communities of Utricularia ochroleuca s.l. and U. intermedia occurred in mineral-poor and those of U. minor and U. australis in mineral-rich conditions. Rare stands with U. vulgaris occurred in conditions that were intermediate in mineral richness. Four communities belonging to the class Isoëto-Littorelletea were distinguished. Vegetation without bladderworts and dominated by E. quinqueflora occurs in calcareous fens and belongs to the class Scheuchzerio-Caricetea fuscae (the Caricion davallianae alliance). Vegetation with U. intermedia is characterized by high vascular plant cover and belongs to the class Scheuchzerio-Caricetea fuscae. Utricularia ochroleuca s.l. prefers open, acidic and waterlogged depressions in peat, whereas U. intermedia grows mostly in the shade under vegetation canopy. In this study, U. minor and U. australis have been found mainly in the more alkaline and mineral-rich habitats, and both species also tolerated extremely high mineral richness.
A phytosociological synthesis of the segetal vegetation in the Czech Republic was performed using methods of the Zürich-Montpellier school. In total, 712 relevés made by the author in this country in 1955–2000 were classified, and 22 associations and one unranked community were distinguished. Each syntaxon is characterized by diagnostic species, documented by a synoptic table, and the syntaxonomy, structure, species composition, ecology, dynamics, distribution and variability of each syntaxon are commented on. Names are revised according to the rules of the International Code of Phytosociological Nomenclature. All syntaxa belong to the class Stellarietea mediae and associations are assigned to the orders Centaureetalia cyani (alliances Caucalidion lappulae, Fumario-Euphorbion, and Sherardion), Atriplici-Chenopodietalia (alliances Scleranthion annui, Polygono-Chenopodion polyspermi, Arnoseridion minimae, and Panico-Setarion), and Eragrostietalia (alliance Eragrostion).
Typology of dry-mesic oak forest vegetation of Slovakia is presented. Seven vegetation types were distinguished based on a Braun-Blanquetian relevé data analysis using a TWINSPAN classification algorithm. The identified vegetation types are related to seven syntaxa traditionally used by Central European phytosociologists: dry-mesic oak forest on sandy soils – Carici fritschii-Quercetum roboris, dry-mesic oak forest on heavy soils – Potentillo albae-Quercetum, dry-mesic oak forest on basic rocky substrates – Corno-Quercetum, dry-mesic oak forest on acidic substrates – Sorbo torminalis-Quercetum, dry oak forest on loess – Quercetum pubescenti-roboris, dry-mesic oak forest on loess – Convallario-Quercetum roboris, dry-mesic forest of Turkey oak – Quercetum petraeae-cerris. Detrended correspondence analysis was used to visualize the similarity of vegetation types. Some aspects of dry-mesic oak forest ecology, distribution and dynamics in Slovakia are discussed; their general retreat due to mesophilous tree species expansion is stressed.