Tuexenia : Mitteilungen der Floristisch-Soziologischen Arbeitsgemeinschaft, Band 30 (2010)
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- Festuco-Brometea (2)
- Molinio-Arrhenatheretea (2)
- Slovakia (2)
- phytosociology (2)
- topography (2)
- vegetation classification (2)
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- Bromo pannonici-Festucion pallentis (1)
- CCA (1)
- Calamagrostis epigeios (1)
A systematic survey of grassland communities in central Slovakian sub-montane and montane regions (including the Kremnické vrchy Mts., Starohorské vrchy Mts., Veľká Fatra Mts., and Zvolenská kotlina Basin) was performed between 1996 and 2007. The main aim was to identify main environmental gradients in the studied vegetation and to estimate the most important individual variables responsible for the variation of their species composition. Along with the floristic composition, the environmental variables were either recorded in the field (altitude, slope, aspect), calculated (solar radiation, climatic data, and phytochorological affinity), or derived from available maps or GIS digital data layers (type of bedrock, soil parameters). These environmental variables were used as supplementary in the detrended correspondence analysis (DCA) or explanatory in the canonical correspondence analysis (CCA). The affiliation of individual phytosociological relevés to associations was estimated by an electronic expert system for Slovak grassland communities. Altogether, 15 xero-, sub-xero- and mesophilous grassland associations were distinguished. Wet and fen meadows were analysed at the level of alliances. Unconstrained ordination revealed moisture and nutrient gradients as most important for the data set. By means of constrained ordination, the variability of the studied vegetation could be explained by a set of geological, topographic, phytochorological and derived climatic variables, although the percentage of explained variance was rather low and did not exceed 12% for all significant factors combined. Among individual variables, the geological bedrock type, climatic water balance, solar radiation, and slope played the most important role in determining the distribution and variability of individual grassland communities. Affinity to phytochorions determined according to local air temperature gradients was also significant. Soil properties played only a subordinate role in our analyses. The analysis of a more homogeneous subset of the data without wetland relevés gave similar results as the analysis of the complete data set. The differences in results of constrained and unconstrained ordinations are discussed together with the potential reasons for extremely high proportion of unexplained variance revealed by the variation partitioning methods.
The aim of this study is to assess the development of plant species diversity and species composition over a seven-year period in two calcareous grasslands abandoned for nearly 20 years and to find out which factors influence vegetation dynamics. In the Abava River valley, Latvia, different calcareous grasslands were studied, one on the south-west facing slope and another on the north-east facing slope. Vegetation analyses on permanent plots showed that dry calcareous grasslands can be resistant to deterioration for a long period of time – succession was slower than reported in many cases for Central and Western Europe. None of the studied communities showed a decrease neither in total species number recorded per community nor in average species richness per plot. Vascular plant species richness even increased by 3–4 species per 1-m2 plot in the grassland on the south-west facing slope. An unexpected result of the research was that Calamagrostis epigeios did not expand in this grassland. This fact can be explained by the influence of disturbances (drought, tree cutting) and local differences in soil parameters and topography. In parts of the north-east exposed grassland, with deeper soils and better water availability, species diversity (Shannon index) decreased significantly in areas overgrown by Aegopodium podagraria.
At the edge of the Harz Mountains in Lower Saxony a population of the hart's tongue fern (Asplenium scolopendrium) threatened by destruction by a gypsum quarry were transplanted into a dolina which was not populated by the species at that time, and the new population was followed over ten years. 90% of the 59 transplanted plants survived this period and grew larger during the first six years after transplantation. Progenies appeared in the third year after transplantation. Nowadays, in the tenth year after transplantation, there are 1110 progenies, 171 of which are reproducing. Overall, the population increased by 1781% in the ten years. Plants that were planted on a rocky slope or a boulder heap in the new habitat, where soil was available, grew better than plants in rock faces without soil. In contrast, in the rock faces, where substrate was not covered with autumn foliage, more juveniles established. The distance between juveniles and mother plants rarely exceeded three meters, which indicates a limited dispersal potential of the hart’s tongue fern and may explain together with low diaspore pressure as a result of local rarity of the species that the dolina had not been colonized spontaneously. We conclude that transplantations of adult plants or introduction of spores are a suitable measure for preserving hart’s tongue fern populations that are endangered by destruction. In the long run, however, such measures cannot compensate for ongoing destruction of natural habitats by mining activities in the gypsum karst region at the southern edge of the Harz Mountains.
The paper presents a new classification and information about associations of the order Fagetalia sylvaticae on the territory of Ukraine. The order includes 9 alliances (Asperulo-Fagion, Cephalanthero- Fagion, Carpinion betuli, Tilio platyphylli-Acerion pseudoplatani, Dentario quinquefolii-Fagion, Paeonio dauricae-Quercion petraeae, Querco roboris-Tilion cordatae, Scillo sibericae-Quercion roboris, Alnion incanae) and 31 syntaxa of the level of association. The synoptic table contains data on constancy of species in all associations with constancy more than 10%. Maps of distribution of these associations in Ukraine are given.
New vegetation data of dry grasslands in the Western Carpathians and the northern Pannonian Basin
(2010)
The paper presents new vegetation data from dry grassland sites in the biogeographical regions of the Western Carpathians and the northern Pannonian Basin, mainly belonging to the alliances Bromo pannonici-Festucion pallentis and Festucion valesiacae (Festuco-Brometea). The 124 phytosociological relevés were sampled between 2005 and 2009 in Slovakia, the SE Czech Republic, NE Austria, and N Hungary. They are classified into 16 associations and four transitional vegetation types. The paper also brings new information on the distribution of grassland associations in the study area. A new locality of the rare association Teucrio botryos-Andropogonetum ischaemi was confirmed. During our recent investigation of historical sites of the Alopecuro pratensis-Festucetum pseudovinae (Cynosurion cristati, Molinio-Arrhenatheretea) in the Slaná river floodplain, only one occurrence could be confirmed. Geographical principles in distribution of dry grassland associations and classification of the Stipa pulcherrima-dominated stands are also discussed.
Plant species diversity and species ranges were investigated in two siliceous mountain regions: the Central Alps (Nature Park Texelgruppe, South Tyrol, Italy) and Central Greater Caucasus (Cross Pass area, Kazbegi region, Georgia). Altitudinal gradients from the treeline ecotone to the upper alpine/ subnival and nival zone, respectively, are compared. The research was carried out within the projects GLORIA-Europe (Global Observation Research Initiative in Alpine Environments) and GLORIA-worldwide. The idea of the GLORIA projects is to describe the actual diversity (= task of the first recording), and to observe diversity changes and migrations of low-altitude species to higher altitudes (= task of the monitoring every 5–10 years). The objective of this paper is to analyse (1) altitudinal gradients from the treeline to the nival zone in the Central Caucasus and in the Central Alps, (2) floristic similarities between the two mountain regions, (3) signs of migrating montane species to higher altitudes in both regions. In each mountain region four summits were selected and 3 x 3 m square clusters were established at the 5 m contour line below the highest summit point in each of the four main compass directions. In the four corner plots (4 x 1 m²) of the square cluster plots frequency analyses were performed and vegetation cover was estimated. Additionally, species sampling was made from the highest summit point down to the 10 m contour line of each summit. The species were classified according to their distribution (endemic vs. non-endemic species) and their altitudinal range (colline-montane-treeline-alpine-subnival-nival species). The total species number of the GLORIA summits in the Central Caucasus was 116, in the Central Alps 140. Differences between the two mountain regions were detected regarding species diversity per summit, number of endemic species and altitudinal ranges of the species. In the Central Alps, a high number of montane species was present at the treeline ecotone in contrast to the Central Caucasus, where species of lower altitudes did hardly occur at the investigated summits.
The Târnava Mare EU Site of Community Interest (SCI), Romania, is a landscape of high grassland biodiversity, which includes small areas of xeric grasslands. These forest-steppe associations have some unique habitat species compositions and contain small populations of EU Habitats Directive and Romanian red-listed plant species. The grasslands are in need of a conservation strategy that will fully describe their legal conservation status, identify threats and deliver their management requirements. The conservation programme is discussed with regard to a newly discovered and exceptional stand of xeric grassland allied to ‘stony steppe’ formations, which is presented as an example of the factors involved in the protection of such sites.
This paper presents a study on a population of Pulsatilla patens conducted in 2009 in the Natura 2000 wildlife refuge called "Grasslands in the Military Training Grounds in Orzysz" in the Masurian Lake District (NE Poland). The purpose of the study was to determine the population structure of Pulsatilla patens, especially with regard to abundance, density, and percentage of life cycle stages in the total population. Correlations were examined between these population features and selected environmental characteristics including cover of phanerogams, cryptogams, litter, and bare soil. For the evaluation of the linear relationship between the variables, Spearman's correlation coefficient was used. In order to identify the factors that have significant influence on the values of the dependent variables, a multiple regression analysis was performed. In total, 316 individuals of Pulsatilla patens were recorded: 62 flower ing adults, 202 vegetative adults and 52 juveniles. The number of flowers per individual varied from one to 12, the average being three flowers. Most individuals occurred in dry heath, and the smallest number of individuals was found in pine forest. The mean density per habitat ranged from one to 11 individuals per 4 m2. Increased cover of phanerogams and cryptogams caused a decrease in the density of Pulsatilla patens individuals.
In our contribution, we report on the 6th European Dry Grassland Meeting held from 31 August to 1 September 2009 in Halle (Saale), Germany. The meeting was attended by 40 participants, who gave 15 oral and 17 poster presentations. The rapid positive development of the European Dry Grassland Group (EDGG), the organiser of this conference, is mentioned: the inclusion of the EDGG in the International Association for Vegetation Science (IAVS) as a working group, the establishment of two new subgroups focussing on Mediterranean and South-East European dry grasslands, respectively, and the organisation of the first EDGG research expedition in 2010 belong to the most important events. In the last part of our contribution, we give a short introduction to the six articles of this Special Feature. Two of them deal with phytosociological classification of semi-natural grassland communities, one with vegetation- environment relationships. Two papers are concerned with conservational topics, one focussing on the population structure of endangered Pulsatilla patens, the other dealing with conservation of xeric grasslands in Transylvania. The last paper examines temporal changes in calcareous grasslands with regard to species diversity.
The main aim of this paper was to test the national electronic expert system for grassland classification in Slovakia as a tool for grassland classification on a regional data set from an area with high vegetation diversity. The study region comprised five orographic units located in central Slovakia (Starohorské vrchy Mts., Kremnické vrchy Mts., Veľká Fatra Mts., Nízke Tatry Mts. and Zvolenská kotlina Basin). The data set included 411 phytosociological relevés of all grassland types (xero-, subxero- and mesophilous grasslands as well as wet and fen meadows), recorded by the authors between 1980 and 2007. The relevés were classified to associations by the expert system formulated for the Slovak grassland vegetation either according to association definitions or (in case of relevés not matching any association definition) according to the Frequency-Positive Fidelity Index (FPFI). Wetland relevés were classified according to results of a cluster analysis. Diagnostic species from the regional data were compared to diagnostic species derived at the national level from the data including all vegetation units in Slovakia. According to the results, 49% of the relevés classified by the expert system were matched by the association definitions. Xerophilous grasslands were classified within three alliances of the class Festuco- Brometea: Festucion valesiacae, Bromo pannonici-Festucion pallentis and Diantho lumnitzeri-Seslerion. The occurrence of these communities in the region is rare, restricted to rocky habitats and steep slopes with shallow soil over calcareous bedrock. Sub-xerophilous grasslands were classified within four associations belonging to the two alliances Cirsio-Brachypodion pinnati and Bromion erecti. In the study region, these communities are widely distributed mainly in areas built by calcareous bedrock. Mesophilous grasslands are the most common communities in the study region. They were classified within eight associations belonging to four alliances: Cynosurion cristati, Arrhenatherion elatioris and Polygono bistortae-Trisetion flavescentis (all of them belonging to the class Molinio-Arrhenatheretea) and Nardo strictae-Agrostion tenuis (belonging to the class Nardetea strictae). Wetland communities belonged to the classes Phragmito-Magnocaricetea (alliances Phragmition communis and Glycerio-Sparganion), Molinio-Arrhenatheretea (alliance Deschampsion cespitosae) and Scheuchzerio-Caricetea fuscae (alliance Caricion davallianae). The results demonstrate that the national expert system used can be successfully applied to a heterogeneous regional data set without discarding the particularities of the regional vegetation. The uniqueness of the regional vegetation is reflected in the set of diagnostic species determined at the regional level, which can differ strongly from those estimated at the national level.