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.
Habitats of pre-hibernating gregarious larvae of the endangered Marsh Fritillary butterfly (Euphydryas aurinia) were studied in field in Western Bohemia, Czech Republic. The species inhabits moist seminatural meadows managed by light grazing and haymaking; the only local host plant is Succisa pratensis. The redundancy analyses of the vegetation composition (around 166 nest-bearing and 381 unoccupied host plants) showed that nest presence was positively associated with short cushion-forming grasses (esp. Nardus stricta). It was negatively associated with competitively superior tall grasses (e.g., Deschampsia caespitosa) and tall herbs. Comparison of Ellenberg's indicator values of vegetation in occupied vs. unoccupied plots revealed that the nests were more often found in drier, nitrogen-poorer and more acidic conditions than unoccupied plants. Multiple regressions of nest presence against architecture of the host plants (170 occupied, 1280 unoccupied) revealed that the nests were associated with densely clumped host plants, low to medium height of sward and mechanical disturbance. The patterns agree with our knowledge of the biology of the larvae: short sward (related to low nitrogen, humidity, and low pH) facilitates larval basking; high host density reduces the likelihood of starvation. Sod disturbance facilitates host plant germination. The conditions favourable for the nests were also favourable for the host plant, but the plants grew in broader range of conditions than that occupied by the nests. The abandoning of a site results into a situation when the conditions first become intolerable for the butterfly, and ultimately for the plant. Since grazing and mowing have a different impact on vegetation composition and architecture, we propose that the studied populations have persisted in a semi-dynamic state in the two modes of management. Conservation management should mimic the dynamics of traditional land use on the smaller scales of extant colonies.
Nineteen isolated rocky outcrops of different sizes, tops of which were covered with natural grassland vegetation, were studied in the forested submontane belt (630–1020 m a.s.l.) of the Šumava Mts in the southern part of the Czech Republic, Central Europe. The species of vascular plants present in the treeless sites at each locality were identified. Those species with an Ellenberg indicator value for light equal 6 or higher were considered to be heliophilous. The distance to the nearest secondary treeless area was measured. There were 43 heliophilous species (23%) recorded among the 184 species identified. The number of species and the number of heliophilous species varied independently of the altitude and extent of the treeless area on the rocky outcrops, but were significantly correlated only with the distance to man-made treeless areas. The highest number of heliophilous species was recorded within approximately 400 m from the nearest man-made treeless area. Although the relict occurrence of some of the heliophilous species on the rocky outcrops cannot be completely excluded, obviously most of the species colonized these localities from nearby secondary treeless areas since their creation in the Middle Ages.
This study was conducted at 17 peatlands in the Czech Republic mined either by the traditional block-cut method or industrially. Phytosociological reléves of 5 × 5 m were carried out in representative parts of successional stages in disturbed peatlands. Age and environmental characteristics were assessed for each relevé (position of water table, water pH, substratum chemistry, geographical area) or each locality (altitude, average annual temperature and precipitation). Phytosociological reléves recorded in natural vegetation, representing the respective target stages, were included into some analyses. Altogether, 210 relevés were analysed by the DCA ordination. Separately, relevés from milled and block-cut sites were elaborated by CCA with marginal and partial effects calculated. Despite the great variability in vegetation, especially among industrially harvested sites, there is a general tendency for peatland vegetation to recover spontaneously, especially at traditionally harvested sites, which all were, however, older than 50 years. The vegetation at the younger industrially harvested sites exhibited only a tendency to recover. All environmental variables investigated had at least some significant effect on the vegetation pattern, among them, soil pH, water table, nitrates, successional age and geographical location were most important. Abiotic site factors together and geographical location appeared to be more important in determining species composition than successional age.
Variability in vegetation, participation of target and non-target species and the role of the local species pool in the spontaneous succession on acidic bedrock were studied in quarries. The study was conducted in the Českomoravská vrchovina uplands (central Czech Republic). A total of 135 relevés, 5 × 5min size, were used to sample 41 quarries that were abandoned from 1 to 92 years ago. Three types of sites were distinguished: mesic, wet and periodically flooded. Species cover (seven point Braun-Blanquet scale) was visually estimated. The following characteristics were noted: steep rocky slopes, bottoms and levels, dumps and screes as habitat types; age; proportion of the main land-cover categories (arable land, ruderal and urban, grassland,woodland and wetland) in the surroundings up to 100 m and 1 km from each quarry; and the occurrence of target (grassland, woodland, wetland) and non-target (ruderal, alien) species up to 100 m from each quarry. Ordination indicates that the spontaneous succession of vegetation results in the formation of mixed woodland, Alnus and Salix carrs, or tall sedge and Typha beds with scattered Salix, depending on the wetness of a site, surrounding vegetation and land cover. Restoration of target vegetation in the quarries by spontaneous succession is possible and can occur within about 25 years, especially if the target species are present close by.
Species composition, structure and ecological characteristics of the vegetation of two pond types with different management, fishponds and storage ponds, in the Českobudějovická pánev basin (South Bohemia), were compared. A selection of 99 relevés from fishponds and 99 from storage ponds (small ponds used for the storage of marketable fish) made in 2000–2004 were analysed using direct and indirect ordination and ANOVA. The difference between storage ponds and fishponds was found to be more important than gradients correlated with temporal changes, soil moisture and mud depth. Storage ponds had a significantly higher mean number of species, bryophytes, archaeophytes and neophytes and beta-diversity. There were no significant differences in cover values, except of moss layer, which had significantly higher cover in storage ponds. Fishponds had significantly higher mean Ellenberg indicator values for light, continentality, moisture and nutrients. Oenanthe aquatica and Rumex maritimus are typical fishpond species and Amblystegium humile and Eleocharis palustris agg. typical storage pond species. The management of storage ponds is more varied and of different intensity than that of fishponds. It is assumed that management is a crucial factor determining the species richness and influencing the vegetation of these two habitats.