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Semi-dry grasslands were once widely distributed communities, but today they represent some of the most vulnerable habitats in Central Europe. European and national legislation and non-governmental organizations have managed to protect some of the remaining fragments. However, despite their status as Natura 2000 habitats, they are often endangered due to improper management, fragmentation and edge effects from adjacent croplands. By using a sample of 44 semi-dry hay meadows in the south-eastern Alpine Foreland of Styria, we investigated how species-richness and trait composition of semi-dry grassland species respond to variation in patch size, connectivity, abiotic site factors and management regimes. We used linear regression models to identify the most important drivers for richness of typical semi-dry grassland species and thus conservation value. The number of typical semi-dry grassland species was highest in well-connected fragments, i.e. units that shared two or more borders with neighbouring species-rich grasslands. Furthermore, large semi-dry grasslands (> 8000 m²) had highest numbers of semi-dry grassland species and highest relevance for conservation; no difference was found among smaller fragment sizes. Unregular management was associated with increased presence of competitive species which replaced stress-tolerant specialists. Our study indicates that under eutrophication, small fragment size and isolation, only large semi-dry grasslands can sustain a high number of species with high conservation value. The conservation value of smaller semi-dry grassland fragments could be improved by buffer zones, adapted mowing treatments and periodical sheep grazing.
Muránska planina Mts, a small karstic area situated in the southern part of the Western Carpathians in Central Slovakia was chosen as a model region for the study of the variability and diversity patterns of thermophilous and mountain non-forest vegetation on the crossing of the Carpathian and Pannonian bioregions. Altogether, 113 new relevés were sampled using standard methods of the Zürich-Montpellier approach and compared with previously published data. The dataset containing both new and published phytosociological relevés from dry, semi-dry and mesic grasslands (265 relevés) was analysed using the program JUICE 7.0.98. The Beta flexible method, relative Sorensen distance as a similarity measure, and logarithmic transformation of species covers were used for the numerical classification (PC-ORD). The main environmental gradients of species composition were analysed by DCA in the CANOCO 4.5 package using the Borhidi indicator values. The various mosaics of plant communities were detected in succession series from pioneer rocky stands through open rocky grasslands dominated by Festuca pallens, F. tatrae, Carex humilis and Sesleria albicans to closed tall grass communities dominated by Calamagrostis varia and C. arundinacea. Plant communities belonging to six classes (Sedo-Scleranthetea, Festuco-Brometea, Elyno-Seslerietea, Thlaspietea rotundifolii, Mulgedio-Aconitetea and Molinio-Arrhenatheretea) including Pannonian grasslands of the alliance Bromo pannonici-Festucion pallentis and high montane/subalpine grasslands of the alliance Astero alpini-Seslerion calcariae occur together in the study area. High floristic richness and extraordinary diffusion of thermophilous and montane/subalpine elements is characteristic for the majority of the studied plant communities.
We performed a survey of grassland communities in the Ukrainian Carpathians with the aim of: (1) syntaxonomically classifying the meso- and subxerophilous grassland vegetation; (2) analysing the main gradients in their species composition; (3) estimating the effect of selected environmental factors on grassland species composition; (4) assessing the species richness of vascular plants and bryophytes in relation to the measured environmental variables. We collected 46 phytosociological relevés during the growing seasons of 2010 and 2011. Species composition and species richness were studied at two spatial scales (1 m² and 16 m²) in relation to soil parameters (soil depth, pH (KCl), content of P, K, Mg, N and C), management regime (mowing, grazing, ploughing in the past and burning), and other factors (altitude, litter cover, open soil, inclination, solar radiation and animal excrement). Seven grassland types were distinguished belonging to 3 classes and 4 alliances, namely the Nardetea strictae including the Violion caninae (mesic pastures at altitudes of 400–600 m mostly on moderate slopes) and the Nardo strictae-Agrostion tenuis (grasslands on moderate slopes at altitudes of 700–900 m usually managed by mowing and grazing the aftermath); the Molinio-Arrhenatheretea, including the Arrhenatherion elatioris (submontane grasslands originated mostly on former fields after their abandonment in the past) and the Cynosurion cristati (intensive pastures); and the Festuco-Brometea including the Cirsio-Brachypodion pinnati (abandoned grasslands dominated by Brachypodium pinnatum and Inula salicina). Detrended correspondence analysis indicated that the major compositional turnover was related to altitude and soil reaction. A canonical correspondence analysis confirmed that altitude had the strongest effect on species composition in the analysed dataset, followed by management treatments (former ploughing, grazing intensity). For vascular plant species richness, regression tree analysis identified grazing intensity as the most important predictor at the 1 m² scale. At the 16 m² scale, soil humus content was evaluated as the most important predictor of vascular plant species richness, followed by litter cover and grazing intensity. The number of bryophytes was not determined by the studied environmental factors at either of the two spatial scales. Although the number of analysed relevés in this study was limited, our results significantly contribute to the understanding of submontane grasslands in the Ukrainian Carpathians.
Dry grasslands are highly diverse vegetation types of great importance for livestock production in rural Balkan areas. We analysed a large data set of phytosociological relevés of dry grasslands (Festuco-Brometea and Festucetea vaginatae classes) in Serbia to produce the first overview of its classification, distribution, environmental conditions and biodiversity patterns. Phytocoenological relevés from relevant literature sources and our own investigations were stored in the Vegetation Database of Serbia (EU-RS-002) and the Balkan Dry Grassland Database (EU-00-013). After heterogeneity-constrained random resampling, the final dataset contained 1,897 relevés and 1,323 species. Species composition was classified hierarchically by the beta flexible method. We used species ecological indicator values for the estimation of the ecological conditions. Floristic and vegetation diversity and the conservation relevance of various dry grassland types, based on an assessment of endemic and protected species, were analysed. We identified 11 clusters, which were well characterised by their species composition and ecology. The first three clusters included loess and sand steppe grasslands mostly found in the Pannonian part of Serbia (Festucion rupicolae and Festucion vaginatae). The next three clusters consisted of Balkan ultramafic rocky grasslands of the order Halacsyetalia sendtneri, Balkan submediterranean mountain steppe grasslands on calcareous substrates, belonging to the order Astragalo-Potentilletalia and grasslands of the Balkan alliance Saturejion montanae on limestone. The third group of relevés comprised Balkan alliances of dry grasslands on deep soils, the Chrysopogono-Danthonion and sub-continental steppes of the alliance Festucion valesiacae in hilly areas of Serbia, mostly in the thermophilous oak zone. According to ordination analysis (DCA), the main floristic gradient was largely determined by temperature and moisture. The Festuco-Brometea class exhibited high floristic diversity (1,323 plant species) and very high conservation relevance in view of the large number of Balkan endemic species (204). A total of 233 species and subspecies protected by national legislation within the studied vegetation were recorded.
Cryophytic steppes in the Minusinskaya intermountain basin containing plant species that are predominantly distributed in the alpine zone such as Androsace dasyphylla, Dryas oxyodonta, Festuca sphagnicola, Kobresia myosuroides, K. filifolia, Minuartia verna, Oxytropis bracteata, Sagina saginoides, Papaver nudicaule, Patrinia sibirica, Pedicularis lasiostachys, Pulsatilla ambigua, Saussurea schanginiana, which are considered remnants of the Pleistocene vegetation. Based on 89 relevés, we classified cryophytic steppes using the Braun-Blanquet method within two phytosociological classes: Central Asian steppes of the Cleistogenetea squarrosae and West Palearctic steppes of the Festuco-Brometea. Three associations (Androsaco dasyphyllae-Caricetum pediformis, Pulsatillo patentis-Caricetum pediformis and Bupleuro multinervi-Helictotrichetum desertori) with three subassociations and three variants were described with respect to their phytosociological affinities and ecology. DCA ordination showed floristic differences between syntaxa, while correlations of DCA axes and floristic and environmental variables detected substrate type and temperature regime as presumably main drivers for vegetation differentiation. Another driver for vegetation differentiation seems to be continentality of the climate. Small scale distribution of cryophytic steppes were mapped using satellite images with resolution of 1.8 m. Cryophytic steppes always occupy only small areas in landscapes, on convex parts of undulated microrelief of mountain slopes and summits characterised by drought in summer and deep soil freezing in winter. These special micro-ecological conditions play an essential role for the existence of alpine flora in the Minusinskaya intermountain basin.
An extensive survey of the relevant literature of dry grassland communities described for the territory of Serbia allowed us to check the validity and legitimacy of the nomenclature of this vegetation. Nomenclature rules of the International Code of Phytosociological Nomenclature were strictly followed. The syntaxonomic affiliation of communities to higher syntaxa was assessed according to existing syntaxonomic schemes for Serbia and the position determined by the original source. Higher syntaxa followed the synsystem of the socalled “EuroVegChecklist”. We have highlighted problems and some disagreement with the existing classification of dry grassland communities in Europe. A total of 134 dry grassland communities have so far been registered for Serbia. This list of syntaxa may serve for further research of grassland vegetation and its appropriate positioning within a syntaxonomical scheme of Europe.
We present the data of the 2nd research expedition of the European Dry Grassland Group (EDGG), which was conducted in 2010 in Central Podolia, Ukraine. The aim was to collect plot data to compare Ukrainian dry grasslands with those of other parts of Europe in terms of syntaxonomy and biodiversity. We sampled 21 nested-plot series (0.0001–100 m2) and 184 normal plots (10 m2) covering the full variety of dry grassland types occurring in the study region. For all plots, we recorded species composi-tion of terrestrial vascular plants, bryophytes and lichens, while for the 226 10-m2 plots we estimated and measured percentage cover of all species, structural, topographic, soil and landuse parameters. The 10-m² plots were used for phytosociological classification based on iteratively refined TWINSPAN classification as well as for DCA ordination. Differences between the derived vegetation types with respect to environmental conditions and species richness were assessed with ANOVAs. We assigned our plots to nine association-level units but refrained from placing them into formal associations with two exceptions. In the study area, dry grasslands of the Festuco-Brometea were far more common than those of the Koelerio-Corynephoretea. Among the Festuco-Brometea, xeric Festucetalia valesiacae grasslands were more frequent and represented by the Festucion valesiacae (2 associations, including the Allio taurici-Dichanthietum ischaemi ass. nova) and the Stipion lessingianae (1) compared to the Brachypodietalia pinnati with the Agrostio vinealis-Avenulion schellianae (3). The Koelerio-Corynephoretea were represented by three associations, each from a different order and alliance: basiphilous outcrops (Alysso alyssoidis-Sedetalia: Alysso alyssoidis-Sedion?), acidophilous outcrops (Sedo-Scleranthetalia: Veronico dillenii-Sedion albi?) and mesoxeric sandy grasslands (Trifolio arvensis-Festucetalia ovinae: Agrostion vinealis). We discuss the issue of the mesoxeric order Galietalia veri placed within the Molinio-Arrhenatheretea by Ukrainian authors and conclude that the content of that order would probably be better placed in the mesoxeric orders of the Koelerio-Corynephoretea and Festuco-Brometea. Other syntaxonomic questions could not be solved with our geographically limited dataset and await a supraregional analysis, e.g. whether the Ukrainian outcrop communities should be assigned to the same alliances as known from Central Europe or rather represent new vicariant units. The analysis of the biodiversity patterns showed that at a grain size of 10 m2, Podolian Koelerio-Corynephoretea communities were overall richer than Festuco-Brometea communities (46.4 vs. 40.6 species). This difference was due to the Koelerio-Corynephoretea containing twice as many bryophytes and nine times more lichens, while vascular plant species richness did not differ significantly between classes. The orders within the classes showed no real differences in species richness. The richness patterns observed in Podolia were almost the opposite of those usually found in dry grasslands, where Brachypodietalia pinnati are richer than Festucetalia valesiacae, and these richer than stands of the Koelerio-Corynpehoretea – and we do not have a good explanation for these idiosyncrasies. In conclusion, Podolian dry grasslands behave quite unexpectedly regarding biodiversity, and their syntaxonomy is still poorly understood. These knowledge gaps can only be addressed with supranational analyses based on comprehensive datasets.
Syntaxonomic revision of the Pannonian grasslands of Austria : 1. Introduction and general overview
(2013)
The Pannonian part of Austria is a diverse landscape situated in the transition zone between the Alps, the Bohemian Massif and the Carpathian Basin. Although the grasslands of this region have been investigated in many botanical and vegetation studies, their phytosociological classification has remained confusing. With this paper, we start a series aiming at a developement of a revised, consistent system of the Austrian Pannonian grasslands. Here we present a general overview focusing on the higher syntaxonomic units. We define grasslands as all types of meadows, pastures, fens and primary steppes. We selected all available relevés of Pannonian grasslands from the Austrian Vegetation Database. Additional unpub-lished data were included from the Danube National Park and the Biosphere Reserve Vienna Woods. To account for the comparatively low number of relevés from the northern part of the Pannonian region of Austria (Weinviertel), we included also data from southern Moravia (Czech Republic). This set of 3384 relevés was classified using TWINSPAN. Relevés that were considered as misclassified at the alliance level according to the summarised cover of diagnostic species were manually re-arranged, and the data-set specific fidelity of species to alliances was calculated using the phi coefficient. The first TWINSPAN division largely corresponded to the traditional border between the classes Festuco-Brometea and Molinio-Arrhenatheretea. The conventional alliance concepts were generally well supported. As an exception, the distinction between Diantho-Seslerion and Bromo-Festucion pallentis was not reproduced at all. Therefore, we unite all rocky grasslands on calcareous soils in a single alliance Seslerio-Festucion pallentis. We also advocate the inclusion of all basiphilous semi-dry grasslands of the study area within a single alliance Cirsio-Brachypodion. Each of the corresponding TWINSPAN clusters showed a clear prevalence of Cirsio-Brachypodion species. Moreover, two separate alliances of semi-dry grasslands would have almost no regional character species.
As second part of a series focusing on the Pannonian grasslands of Austria, we present a detailed classification of the grasslands of the Vienna Woods (Wienerwald). This region, although geographically belonging to the Alps, has strong floristic affinities to the Pannonian Basin. The eastern slopes of the Vienna Woods are a hotspot of xero-thermophytic vegetation and exhibit the highest vascular plant species richness in Austria at a scale of 3' x 5'. We used the TWINSPAN classification of a large data set reported in the first part of this series as starting point. Relevés that were considered as misclassified at the level of alliances were manually re-arranged. From this table, an excerpt containing only the relevés of the Vienna Woods was used for the present study (1055 plots). We re-classified the relevés preliminary labelled as Arrhenatherion with another TWINSPAN run. Clusters for which no ecological difference could be detected were merged. The final delimitation of associations and subassociations was achieved by adjusting their diagnostic species so as to get units that were most informative in terms of environmental conditions. All re-arrangements were based on the summarised cover of diagnostic species within individual relevés. As a result, the grasslands of the Vienna Woods are classified within 22 associations (plus two subassociations) belonging to ten alliances and four classes. Within the Seslerio-Festucion pallentis, a new association Scorzonero austriacae-Caricetum humilis is described. The semi-dry grasslands of the study area previously classified as Onobrychido-Brometum are de-scribed as new association Filipendulo vulgaris-Brometum erecti and assigned to the Cirsio-Brachypodion. The Anthoxantho-Agrostietum tenuis is reported for Austria for the first time, and its syntaxonomy is discussed within a broader geographical context.
Dry grasslands of NW Bulgarian mountains : first insights into diversity, ecology and syntaxonomy
(2013)
We present the data of the 3rd research expedition of the European Dry Grasslands Group (EDGG), which was conducted in 2011 in two contrasting areas in NW Bulgarian mountains. The aim was to collect plot data for comparing Bulgarian dry grasslands with those of other parts of Europe in terms of syntaxonomy and biodiversity. We sampled 15 nested-plot series (0.0001–100 m²) and 68 normal plots (10 m²) covering the full variety of dry grassland types occurring in the Vratsa area (Balkan Mts.) and the Koprivshtitsa area (Sredna Gora Mt.). In the plots all vascular plants, terricolous non-vascular plants and a set of soil and other environmental parameters were determined. By applying modified TWIN-SPAN, we distinguished 10 floristically well characterised vegetation types at the association level. After comparison with the regional and European literature, we propose to place them within three classes and five orders: Festuco-Brometea with the orders Stipo pulcherrimae-Festucetalia pallentis (xerophilous dry grasslands of base-rich rocks; alliance Saturejion montanae), Brachypodietalia pinnati (meso-xeric, basiphilous grasslands; alliances Cirsio-Brachypodion pinnati and Chyrsopogono grylli-Danthonion calycinae), Calluno-Ulicetea with the order Nardetalia stricae (lowland to montane Nar-dus swards; alliance Violion caninae), and Koelerio-Corynephoretea with the orders Sedo-Scleranthetalia (open communities of skeleton-rich, acidic soils; alliance unclear) and Trifolio arvensis-Festucetalia ovinae (closed, meso-xeric, acidophilous grasslands; alliance Armerio rumelicae-Potentillion). The Violion caninae with the association Festuco rubrae-Genistelletum sagittalis is reported from Bulgaria for the first time, while the two occurring Koelerio-Corynephoretea communities are described as new associations (Cetrario aculeatae-Plantaginetum radicatae, Plantagini radicatae-Agrostietum capillaris). According to DCA the main floristic gradient was largely determined by soil conditions, differentiating the Festuco-Brometea communities on soils with high pH and high humus content from the Koelerio-Corynephoretea communities on acidic, humus-poor soils, while the Calluno-Ulicetea stands are the connecting link. At 10 m2 Festuco-Brometea and Calluno-Ulicetea stands were richer in species across all investigated taxa and in vascular plants than Koelerio-Corynephoretea stands; the latter were richest in lichen species, while bryophyte richness did not differ significantly among syntaxa. Among the Bulgarian classes, the species-area relationships tended to be steepest in the Festuco-Brometea (i.e. highest beta diversity), but both alpha and beta diversity clearly fell behind the Festuco-Brometea communities in the Transylvanian Plateau, Romania, located less than 500 km north of the study region. Overall, our study contributes to a more adequate placement of the Bulgarian dry grasslands in the European syntaxonomic system and provides valuable data for large-scale analyses of biodiversity patterns.
In the lower siliceous uplands of Central Europe, various types of nutrient-poor grasslands are widespread and grow intermingled. These species-rich grasslands, often dominated by taxa of the Festuca ovina aggregate, comprise various phytosociological classes. They are remnants of a historic rural lands - cape and are of conservation importance. Few studies on such grasslands are available and there has been disagreement in assigning them to appropriate habitat types or syntaxa. We investigated such nutrient-poor grasslands in the lower Aar valley (Middle Hesse, Rhenish Massif). We surveyed 104 vegetation plots distributed throughout the valley and identified syntaxa to (sub)association level. We carried out supervised classification combining cluster analysis, a priori assignment to classes based on prevailing diagnostic species, and regional refinement based on phi-value maximisation of the units. As a result, we classified five associations within four classes: Polytricho piliferi-Festucetum tenuifoliae/Galio harcynici-Deschampsietum flexuosae and Festuco rubrae-Genistelletum sagittalis (Calluno- Ulicetea), Jasiono montanae-Festucetum ovinae (Koelerio-Corynephoretea), Gentiano-Koelerietum pyramidatae (Festuco-Brometea) and Arrhenatheretum elatioris (Molinio-Arrhenatheretea). Ecologically, soil acidity (resulting from Ca concentrations of the bedrock) was the main cause of floristic dissimilarity of the grasslands and thus community differentiation. Many stands grew on soils with intermediate pH and showed a peculiar mixture of basiphilous and acidophilous species. We conclude that (i) our approach of supervised classification yields convincing reproducible results when a syntaxonomic system is adapted top-down to a geographically restricted area, (ii) nutrient-poor siliceous grasslands dominated by taxa of the Festuca ovina aggregate can be well assigned to ecologically meaningful syntaxa, and (iii) the nutrient-poor siliceous grasslands of the Lahn-Dill Highlands are of high conservation relevance and in urgent need of protection.
We report on the activities of the European Dry Grassland Group (EDGG) during the last year, namely the 8th European Dry Grassland Meeting in Uman', Ukraine in June 2011, the 3rd EDGG Research Expedition in Bulgaria in August 2011, the 4th EDGG Research Expedition in Sicily in April 2012, as well as the completed and forthcoming EDGG-coordinated special features in international journals. Then we provide a brief bibliometrical analysis of the Dry Grassland Special Features in Tuexenia since 2005. The 32 contributions of the years 2005–2011 constituted approx. 17% of the overall content of Tuexenia in this period. Including this 7th Dry Grassland Special Feature, sixty-one authors from 12 countries have contributed to these Special Features, guest-edited by yearly changing teams from a total of 16 guest editors. In the years with statistically reliable data, contributions in the Dry Grassland Special Features have been cited approximately four times as much as regular Tuexenia contributions. It is likely that this fact together with the internationality of the Special Features has contributed to the final inclusion of the journal in the Web of Science in 2011. Finally, we introduce the four research articles of this 7th Dry Grassland Special Feature. Two of them are focusing on vegetation change and restoration issues of cryptogam-rich sand dunes in the Netherlands and calcareous grasslands in Bavaria (Germany), respectively. The others, dealing with siliceous grasslands in Hesse (central Germany) and the results of EDGG Research Expedition 2009 to Transylvania (Romania), focus on syntaxonomy.
A long-term systematic survey of grassland communities was performed in the Biele Karpaty Mts. in Slovakia. The main aims of the research were i) syntaxonomical classification of meso- and subxerophilous grassland vegetation, ii) analysis of the main gradients in species composition, iii) evaluation of the effect of environmental factors on species composition of grasslands. The data set included 342 phytosociological relevés of grasslands recorded between 1991 and 1999. For the classification of relevés to associations, the expert system for identification of grassland vegetation of Slovakia was used. The main environmental gradients of species composition were analysed by detrended correspondence analysis (DCA). For the ecological interpretation of ordination axes Ellenberg indicator values were used. The relationship between species composition and environmental factors (geology, pedology, climate, topography, management) was analysed by canonical correspondence analysis (CCA). The expert system identified (according to association definitions) 220 phytosociological relevés (64% of the whole data set). Grassland communities were classified within seven associations belonging to four alliances and three classes: Festuco-Brometea: Bromion erecti and Cirsio-Brachypodion pinnati; Molinio- Arrhenatheretea: Arrhenatherion; Nardetea strictae: Violion caninae. The results of the DCA support our assumption that the main environmental gradient in species compositions of grasslands is related to moisture and soil reaction (content of CaCO3 in the soil). The results of the direct gradient analysis (CCA) show that all 23 environmental variables explained 16.15% of the variability of the species data. The most important factors affecting the data variation were precipitation and geological bedrock.
Using four exclosures, the impact of mouflon grazing and weather on plant communities of the phytosociological alliances Koelerio-Phleion phleoidis and Hyperico perforati-Scleranthion perennis occurring on shallow soils within a forest landscape was studied in the Křivoklátsko Biosphere Reserve (Czech Republic) during seven years. In the years 2004–2010, the vascular plant species composition was recorded annually on a total of eight fenced and eight control plots, each 2 m × 1 m in size. Treatment, time, and weather data were used as explanatory variables in ordination and correlation analyses. Cover values of different life forms and indicator values varied significantly in dependence on the weather conditions of the preceding five months; however, correlations varied according to the vegetation type and were rather rarely detected. The effect of fencing appeared important in all study plots; however, the temporal trends were significant only in half of them. We did not find a significant interaction between treatment and time in the total dataset. A successional change was detected in one fenced plot only; in all other cases, the species composition fluctuated – a phenomenon that is not directly attributable to weather conditions. In the fenced plots, the herbaceous vegetation cover decreased, mainly due to litter accumulation and partly due to shrub encroachment. At least some parts of the valuable and species-rich habitats could be maintained under high game density, but some parts are endangered by eutrophication and game grazing. Nature conservation management should balance both mechanisms.
We first report from the 7th European Dry Grassland Meeting held 27 May to 1 June 2010 in Smolenice, Slovakia, devoted to the main topic "Succession, restoration and management of dry grasslands". Apart from the scientific programme and the excursions, we also summarise the outcomes of the General Assembly of the EDGG and present the Smolenice Grassland Declaration. Then we take stock of the dynamic development of the European Dry Grassland Group (EDGG), report on its activities during the past year, and announce its future plans. Finally, we give a short introduction to the four articles of this Special Feature, which deal with biodiversity patterns, vegetation classification, and dynamics of dry grassland habitats. One presents a detailed phytosociological study of the xeric and mesic grasslands of the Slovak part of the Biele Karpaty Mts. The second provides a new numeric approach to the assignment of relevés to syntaxa and exemplifies this in a case study for the delimitation of the classes Festuco-Brometea against Trifolio-Geranietea sanguinei in Austria. The third article investigates the septennial impact of mouflon grazing and weather on dry grassland plant communities in dry grassland patches of the Czech Republic. The fourth article deals with long-term abandonment of grasslands in Central Slovakia and shows the importance of vegetation structure, ecological stability, and low-disturbance regime for specific ant assemblages.
Der typische Sukzessionsverlauf auf basenreichen offenen Sandstandorten im Binnenland führt von Pionierstadien der Koelerio-Corynephoretea zu artenreichen Allio-Stipetum-Beständen (Festuco-Brometea). Innerhalb weniger Jahre können sich aber auch artenarme Dominanzbestände mit hohem Ruderalisierungsgrad entwickeln, die durch generalistische konkurrenzstarke Graminoide bestimmt werden. 32 Dauerbeobachtungsflächen, die ohne Pflegemanagement sind und mittlerweile seit bis zu 15 Jahren von uns untersucht werden, ermöglichen einen detaillierten Blick auf die unterschiedlichen Sukzessionslinien und die Geschwindigkeiten, mit denen sich Änderungen in der Artenzusammensetzung vollziehen. Dabei stehen uns neben den Daten der Vegetationsaufnahmen und den daraus abgeleiteten Informationen (wie z. B. mittleren Ellenberg-Zeigerwerten) für verschiedene Flächen auch Boden-Daten (N, P, pH) zur Verfügung. Eine Analyse aller Flächen dokumentiert die relative Stabilität offener Sandvegetation nährstoffarmer Standorte für die untersuchten Zeitfenster. Pioniergesellschaften des Sileno conicae-Cerastietum semidecandri s. l. und Jurineo-Koelerietum glaucae zeigen z. T. strukturelle Änderungen (so z. B. Zunahmen der Kryptogamendeckung). Eine Zunahme von Stipa capillata kann z. T. in 11–12 Untersuchungsjahren im Jurineo-Koelerietum festgestellt werden; dies korrespondiert mit einer Abnahme von Koeleria glauca und z. T. mit einer Ablösung von Tortula ruraliformis durch Hypnum cupressiforme var. lacunosum. Dennoch konnten sich während der Untersuchungsjahre in den Beständen die Arten des Jurineo-Koelerietum halten. Bestände des Allio-Stipetum zeigen in der spontanen Sukzession z. T. lange Stagnationen von mehr als 14 Jahren; vereinzelt tritt der Polykormonbildner Prunus spinosa auf. Stellenweise kommt es mit zunehmender Deckung von Stipa capillata jedoch zu gravierenden Abnahmen der Artenzahl. Bestände, die in ihrer Pionierphase durch höhere Bodennährstoffgehalte (besonders Phosphat) und höhere Ellenberg-Feuchtezahlen gekennzeichnet sind, entwickeln sich innerhalb weniger Jahre zu artenarmen Ruderalbeständen. Die gewonnenen Ergebnisse werden in einem Sukzessionsmodell dargestellt. Für ein Pflegemanagement ergibt sich aus den Ergebnissen, dass intakte Koelerion glaucae-Flächen oft nur sehr extensiv beweidet werden müssen. Insbesondere zur Dämpfung der Ruderalisierung in den nährstoffreicheren Flächen sowie zur Dynamisierung in größeren homogenen Beständen des Allio-Stipetum ist ein Pflegemanagement jedoch eine essentielle Maßnahme. Die in unseren Fällen eingesetzte Schaf- und/oder Eselbeweidung führt zur partiellen Förderung der besonders gefährdeten Pionierstadien im Mosaik mit dem Allio-Stipetum.
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.
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.
This paper compiles and synthesizes the present knowledge of dry grassland vegetation on sandy soils in northern Ukraine, based on published and unpublished sources. In total, 391 relevés from 29 association-level syntaxa of the class Koelerio-Corynephoretea (inch Sedo-Scleranthetea and Festucetea vaginatae), as well as of the alliance Agrostion vinealis from the class Molinio-Arrhenatheretea were used for the analysis. Based on cluster analysis and comparison of synoptic tables, a compact classification scheme of the sandy dry grassland vegetation in the forest and forest-steppe zones of the plains region of Ukraine has been developed. It comprises 10 associations from the Koelerio-Corynephoretea and one from the Agrostion vinealis (Molinio-Arrhenatheretea). The Koelerio-Corynephoretea include four orders in Ukraine: Alysso-Sedetalia, Trifolio arvensis- Festucetalia ovinae, Corynephoretalia canescentis, and Sedo acris-Festucetalia. The Alysso-Sedetalia are represented by two associations, the Aurinio saxatilis-Allietum podolici and the Minuartio auctae- Festucetum pallentis from West Podillya. The associations Stipetum pulcherrimae, Astragalo-Stipetum, and Poetum versicoloris, which also had been included in the Alysso-Sedetalia by some authors, are assigned to the class Festuco-Brometea based on their species composition. All Ukrainian stands of the Trifolio arvensis-Festucetalia ovinae are assigned to the association Thymo pulegioides-Festucetum ovinae. They develop on granite outcrops within Ukrainian crystalline shield. Communities of the Corynephoretalia canescentis are described from the Polissya region, where fluvioglacial sediments dominate. These relevés are provisionally assigned to the associations Corniculario aculeatae-Cory- nephoretum canescentis and Corynephoro-Silenetum tataricae. Sedo acris-Festucetalia communities have mainly been recorded in the Dnieper Valley, and some relevés come from Zhytomyr Polissya. This order includes two alliances. The Koelerion glaucae is represented by two associations, namely Veronica dillenii-Secalietum sylvestris and Diantho borbasii-Agrostietum syreistschikovii. The Festucion beckeri is represented by three associations (Centaureo borysthenicae-Festucetum beckeri, Chamaecytiso ruthenici-Festucetum beckeri and perhaps Poo bulbosae-Caricetum colchicae), which are distributed in the Dnieper Valley. The Agrostion vinealis alliance from the Galietalia veri order has been assigned to the Molinio-Arrhenatheretea. The present analysis revealed a significant similarity among the previously described associations of this alliance, which allowed the reduction of them to one association, the Koelerio-Agrostietum vinealis. It occurs mostly in the Dnieper Valley and its left bank tributaries. Among the right bank tributaries, it occurs only along lower stretches of rivers and around their confluences with the Dnieper. Most of the dry grassland communities on sandy soils within the study area require further detailed investigation.
In this paper we aim to present data on current state of steppe-like grasslands dominated by feather grasses (Stipa spp.) in the Transylvanian Lowland (Romania), and to investigate whether management type affects species composition, biodiversity, or the occurrence of rare and endangered vascular plant species in these grasslands. Twelve grassland stands, originating from nine areas and belonging to two associations, Stipetum lessingianae and Stipetum pulcherrimae from the alliance Stipion lessingianae (Festucetalia valesiacae, Festuco-Brometea), were investigated by phytosociological sampling. Our data set contains 60 relevés originating from differently managed grasslands: grazed and abandoned stands as well as former grasslands afforested with Pinus nigra. Transylvanian stands of the Stipion lessingianae occur on steep, south-facing slopes. The species composition has an accentuated sub-continental character, including several steppe elements of Siberian and Pontic origin, many of them reaching the western edge of their distribution in this region. By comparing the species composition of the two associations, we identified 12 differential species for the Stipetum lessingianae and 19 for the Stipetum pulcherrimae, but these associations also contained many species in common, which underlines their close syntaxonomic relatedness. Grazing vs. abandonment had only a slight influence on species composition and vegetation structure, while afforestation with pines resulted in strong transformations: decreased cover of the herb layer, increased cover of litter, decreased representation of diagnostic (i.e. typical) species of the two associations but increased frequency of woody, ruderal, and mesophytic grassland species. As the Stipion lessingianae belongs to the priority habitats of the Habitats Directive, these alterations call for grassland restoration measures. Our study revealed a lack of high-quality data on the vegetation of steppe-like dry grasslands in southeast Europe, where they have their largest and best-developed stands on the continent. Thus, we emphasize the need for compiling such data and for developing a consistent supranational vegetation classification of Festucetalia valesiacae communities in this region.
We first report from the 5th Dry Grassland Meeting held from 28th to 30st of August 2008 in Kiel, Germany. Then we take stock of the achievements of the German Arbeitsgruppe Trockenrasen and the international Working Group on Dry Grasslands in the Nordic and Baltic Region towards establishment of vegetation databases of dry grasslands in these study regions. At the conference, the European Dry Grassland Group (EDGG) was founded as an international platform of dry grassland researchers and conservationists. As networking tools it provides a homepage on the internet, publishes a quarterly electronical bulletin, and will organise the future European Dry Grassland Meetings. In the last part of this contribution, we give a short introduction to the five articles of this Special Feature. Four of them make a major contribution to supra-national classification of Koelerio-Corynephoretea and Festuco- Brometea communities, respectively, by providing syntaxonomic overviews based on comprehensive data from eastern European countries for which only few data have been available until now. The other major focus of the Feature papers is on degradation and restoration of various types of dry grasslands.
We give a report of the fourth annual symposium of the Dry Grassland Working Group, which was organized in conjunction with the second workshop ‘Floristics and geobotany - Contributions to applied questions’, from 6 to 8 Sept. 2007 in Freising-Weihenstephan. The symposium was entitled ‘Restoration and spontaneous establishment of dry and semi-dry grasslands at traditional and urban-industrial sites’. Additionally, the aims of the Dry Grassland Working Group are shortly outlined and the next symposia of both groups are announced.
Wir untersuchen Zusammenhänge zwischen der Artenzusammensetzung, dem Artenreichtum und den Umweltbedingungen der Schwermetallrasen und Trockenrasen der Bottendorfer Hügel in Nord-Thüringen. In diesem Gebiet wachsen primäre und sekundäre Schwermetallrasen und verschiedene Trockenrasengesellschaften auf nicht-schwermetallhaltigen Böden mit einer artenreichen Xerothermrasen-Flora. Anhand von 206 Aufnahmen unterscheiden wir neun Pflanzengesellschaften aus sechs Verbänden der Klassen Koelerio-Corynephoretea (Sedo-Veronicion, Alysso-Sedion) und Festuco-Brometea (Festucion pallentis, Koelerio-Phleion, Festucion valesiacae, Cirsio-Brachypodion). Vier Trockenrasengesellschaften, in denen die Metallophyten Armeria maritima subsp. halleri und Minuartia verna subsp. hercynica häufig Vorkommen, werden als spezielle Subassoziationen (armerietosum halleri) von vier Assoziationen (Teucrio-Festucetum, Thymo-Festucetum, Filipendulo-Helictotrichetum, Adonido-Brachypodietum) neu beschrieben. In einer DCA mit angezeigten Umweltvektoren bilden die Gesellschaften klare Gruppen. Das Teucrio-Festucetum armerietosum und Thymo-Festucetum armerietosum sind in der DCA mit den Gehalten des Bodens an Kupfer und Blei sowie dem C/N-Verhältnis des Bodens eng korreliert, das Adonido-Brachypodietum teucrietosum und Festuco-Stipetum teucrietosum mit dem pH und Karbonatgehalt des Bodens. Der Artenreichtum an Gefäßpflanzen, Moosen und Flechten nimmt bis pH 7,5 zu und dann ab. Der Artenreichtum steigt mit dem Karbonatgehalt und der Leitfähigkeit des Bodens und nimmt mit dem C/N-Verhältnis des Bodens ab. Der Artenreichtum der Gefäßpflanzen nimmt mit dem Kupfergehalt des Bodens ab, während die Wahrscheinlichkeit des Vorkommens der Metallophyten mit dem Kupfer- und Zinkgehalt steigt. - Unsere Studie zeigt, dass Bodenfaktoren wie der pH und der Karbonatgehalt für die Zusammensetzung und den Artenreichtum der Vegetation auf kontaminierten Böden ebenso wichtig sind wie der Gehalt an Schwermetallen. Schwermetallrasen können daher Trockenrasen auf nicht-schwermetallhaltigen Böden floristisch sehr ähnlich sein.
Classification of higher level vegetation units (orders and alliances) based on numerical methods often yields different results than traditional plant community classification concepts. We performed a numerical cluster analysis of phytosociological relevés from the class Festuco-Brometea in Slovakia with the aim of identifying areas of overlap between the two classification approaches. The research was carried out using a database of approximately 1500 phytosociological relevés sampled in the period between 1927 and 2004. The outputs of the numerical classification form six clusters. Diagnostic taxa of individual clusters were determined using species constancy and fidelity. The cluster analysis enabled us to differentiate the alliances Seslerio-Festucion pallentis, Diantho lumnitzeri-Seslerion albicantis, Festucion valesiacae, Cirsio-Brachypodion pinnati and Asplenio septentrionalis-Festucion pallentis (inch Festucenion pseudodalmaticae). However, it did not permit the differentiation of the alliances Koelerio-Phleion phleoidis and Bromion erecti. It also did not allow us to differentiate the orders Brometalia erecti and Festucetalia valesiacae. The reason for this may be the peripheral occurrence of plant communities of Brometalia erecti in Slovakia.
We present a report on the second annual symposium of the Dry Grassland Working Group, which took place 26.-28.08.05 in Münster and was entitled ‘Observation scales in dry grasslands’ The Dry Grassland Working Group is a discussion forum for all who are dealing with dry grasslands in central Europe. It organises annual symposia on various topics and aims to prepare the volumes on dry grasslands and closely related vegetation classes within the the ‘Synopsis of the plant communities of Germany’ The Synopsis will be based on a TURBOVEG database. As its structure and reference lists are now almost fixed, we will probably be able to start with data input at the beginning of 2006.
Die Arbeitsgruppe Trockenrasen wurde 2004 mit dem Ziel gegründet, mittelfristig die Bände der Trockenrasen und nahe stehender Vegetationstypen innerhalb der „Synopsis der Pflanzengesellschaften Deutschlands“ zu verfassen. Dazu soll zunächst eine umfassende TURBOVEG-Datenbank mit Vegetationsaufnahmen der Klassen Koelerio-Corynephoretea, Festuco-Brometea, Violetea calaminariae, Elyno-Seslerietea und Trifolio-Geranietea sanguinei aus Deutschland erstellt werden. Anschließend ist die ergebnisoffene syntaxonomische Neubearbeitung dieser Gesellschaftsgruppe nach einer einheitlichen Methodik geplant. Personen, die an der Arbeitsgruppe mitwirken oder ihr Daten zur Verfügung stellen wollen, sind herzlich willkommen. Außerdem veranstaltet die Arbeitsgruppe eine jährliche Tagung zu wechselnden Themen. Die erste im September 2004 in Lüneburg stand unter dem Motto „Trockenrasen als Biodiversitätshotspots“. Fünf der damaligen Beiträge werden in diesem Band publiziert.
Trockenrasen (v. a. Klassen Koelerio-Corynephoretea und Festuco-Brometea) gehören zu den auf kleinen Flächen artenreichsten Pflanzengesellschaften überhaupt und stellen ideale Modellsysteme für die Analyse von Phytodiversitätsmustern und deren Ursachen dar. Ich gebe einen Überblick der in verschiedenen Trockenrasentypen Europas auftretenden Durchschnitts- und Maximalwerte der Artenzahlen von Gefäßpflanzen, Moosen und Flechten auf unterschiedlichen Flächengrößen zwischen 1 mm2 und 100 m2. Gesellschaften der Festuco-Brometea sind generell artenreicher als jene der Koelerio-Corynephoretea. Die bislang höchsten publizierten Artendichten stammen jedoch aus dem Gypsophilo fastigiatae-Globularietum vulgaris, einer basiphilen Felsgrusflur der schwedischen Insel Öland (Ordnung Alysso alyssoidis-Sedetalia, Koelerio-Corynephoretea). Sie betragen auf 4 m2 durchschnittlich 53,6 und maximal 80 Arten. Die geringsten Artendichten unter den Trockenrasen weisen das Caricetum arenariae und das Corniculario-Corynephoretum (beide Ordnung Corynephoretalia canescentis, Koelerio-Corynephoretea) mit durchschnittlich weniger als 10 Arten auf 4 m2 auf. Die Artenzahl-Areal-Beziehung von Trockenrasen lässt sich über den ganzen betrachteten Dimensionsbereich exzellent durch eine Potenzfunktion S = c • A z beschreiben. Dabei unterscheiden sich die z-Werte verschiedener Trockenrasentypen nur geringfügig und betragen im Mittel 0,21. Das führt dazu, dass die Reihung verschiedener Trockenrasengesellschaften hinsichtlich ihrer Artenzahl auf unterschiedlichen Skalenebenen nahezu unverändert bleibt, und eröffnet die Möglichkeit, Artenzahlen auf andere Flächengrößen zu extrapolieren.
Es folgt eine Erörterung der wichtigsten Faktoren, welche die Verteilung der Phytodiversität in Trockenrasen beeinflussen. Die größte Bedeutung hat hier die Bodenreaktion. Im Allgemeinen wurden stark steigende Artendichten mit zunehmendem pH-Wert, teilweise auch ein erneuter leichter Abfall oberhalb des Neutralpunktes gefunden. Eine Abnahme der Artendichte mit zunehmender Höhenlage im Gebirge konnte zumindest in zwei Fällen auch für Probeflächen gleicher Größe nachgewiesen werden. Abschließend diskutiere ich die Gründe für den überdurchschnittlichen Artenreichtum von Trockenrasen, weise auf Forschungsdefizite hin und unterbreite Empfehlungen für die Konzeption und Durchführung künftiger Studien der Biodiversitätsforschung wie auch der pflanzensoziologischen Datenerhebung allgemein. Als vordringliche Qualitätskriterien erachte ich die Arbeit mit standardisierten Probeflächengrößen und die sorgfältige Berücksichtigung von Moosen und Flechten.
Im Rahmen des Forschungsschwerpunkts „Kulturlandschaft“ wurden 50 kleine Trockenraseninseln im Osten Österreichs pflanzensoziologisch untersucht und mit Vegetationsaufnahmen dokumentiert. Weiters wurde auf allen Flächen die Korngrößen-Zusammensetzung des Bodens bestimmt. Sämtliche Untersuchungsflächen befinden sich auf tertiären oder quartären Sedimenten. Felstrockenrasen wurden nicht berücksichtigt. Die Bestände können folgenden Gesellschaften zugeordnet werden: Polygalo majoris-Brachypodietum, Astragalo austriaci-Festucetum rupicolae, Ranunculo illyrici-Festucetum valesiacae, Poo angustifoliae-Festucetum valesiacae, Potentillo arenariae-Festucetum pseudovinae und Fumano-Stipetum eriocaulis. Artenzusammensetzung, geographische Verteilung und Böden der Einheiten werden beschrieben. Im Anschluss werden einige Probleme der syntaxonomischen Gliederung der westpannonischen Trockenrasen diskutiert.
Das Gipskarstgebiet am Südharzrand zeichnet sich durch ein Klimagefälle aus, das durch einen Florenwandel nachgezeichnet wird. So erreichen insbesondere eine Reihe von (sub-)kontinental verbreiteten Pflanzenarten im Gebiet ihre westliche Verbreitungsgrenze. Parallel mit der Verbreitungsgrenze von Arten geht auch die Verbreitung der Kalkmagerrasen-Gesellschaften. Gesellschaften der kontinental verbreiteten Ordnung Festucetalia valesiacae kommen nur im Ostteil des Gebietes vor. Im Westen dominieren Bestände des Verbandes Mesobromion, der jedoch auch im Ostteil des Südharzes nicht fehlt. Exemplarisch werden zwei Gebiete aufgesucht, in denen diese floristischen und pflanzensoziologischen Unterschiede vorgestellt werden. Die Umgebung von Walkenried mit dem Naturschutzgebiet Priorteich-Sachsenstein ist nicht nur repräsentativ für die westlichen Magerrasen, sondern zeichnet sich außerdem durch eine ganz eigene Flora mit dealpinen Reliktarten aus. Der nordöstlich von Nordhausen gelegene Singerberg weist dagegen schon eine ganze Reihe von (sub-)kontinentalen Florenelementen und Pflanzengesellschaften auf, die hier auf sehr kleinem Raum nebeneinander vorkommen. Diese einzigartige Gipskarstlandschaft des Südharzes ist akut bedroht durch den ständig fortschreitenden Gipsabbau, der auch im Verlauf der Exkursion nicht zu übersehen sein wird.
Innerhalb geschlossener Waldbestände existieren im Naturraum Harth der elsässischen Rheinebene (Frankreich, Haut-Rhin) Lichtungen, die von artenreichen Trockenrasen-Gesellschaften bewachsen sind. Nachdem bisher von einer weitgehenden Natürlichkeit der Trockenrasen-Lichtungen in den Wäldern ausgegangen wurde, kann dieser Sachverhalt anhand von eigenen pedologischen Transektuntersuchungen und einer Aufarbeitung der vegetationsprägenden Nutzungsgeschichte differenziert betrachtet werden. Das trockene Klima wirkt im Naturraum als prägender Faktor für die Vegetation und Bodenentwicklung und läßt das pflanzenverfügbare Wasser zur entscheidenden Größe werden. Im Gebiet liegt die Grenze für lückige Waldbestände mit Lichtungen innerhalb der Colmarer Trockenzone mit durchschnitlich 600 mm Jahresniederschlägen bei rund 50 mm/m3. Die Bodenbildung wurde durch die Vegetation stark beeinflußt. Schwach saure, skelettreiche Pararendzinen und Basenreiche Braunerden ohne Kalkausfällungshorizont und mit fehlender Rubefizierung weisen bei gleichzeitig sehr geringer nutzbarer Feldkapazität (rund 50 mm/m3) auf natürlich waldfreie Standorte hin. Nur ein geringer Teil der Bodenprofile unter Lichtungen entspricht diesen Kriterien, die überwiegende Zahl der Freiflächen ist deshalb anthropogen. In zwei untersuchten Wäldern sind nach einem Luftbildvergleich 75-80% der Trockenrasen in den letzten 40 Jahren von Gebüschen bewachsen worden, was den zooanthropogenen Ursprung der Lichtungen unterstreicht. Die Trockenrasengesellschaften werden auf der Basis von 250 Vegetationsaufnahmen charakterisiert und verglichen. Im Zentrum der Untersuchung steht das Agrostio-Brometum Issler ex Oberdörfer et Korneck 1978 (V Koelerio-Phleion), das neu gefaßt wird. Syntaxonomisch gefaßt wurden aus der Klasse Festuco-Brometea das Mesobrometum Br.-Bl. ap. Scherr. 1925, eine Xerobromion-Fragmentgesellschaft und das im Gebiet an seiner westlichen Verbreitungsgrenze stehende Adonido-Brachypodietumpinnati (Libb. 1933) Krausch 1961. Das Festuco-Genistetum sagittalis Issl. 1927 (Nardo-Callunetea Prsg. 1949) des Naturraums wurde in eine eigene Subassoziation von Filipéndula vulgaris gestellt und vermittelt zu den Trockenrasen der Festuco-Brometea. Stark basen- bis kalkliebende Arten können im Naturraum nur durch die Veränderung der natürlichen Bodenhorizontierung Vorkommen. Die entsprechenden Pflanzengesellschaften (Xerobromion-Gesellschaft, Adonido-Brachypodietum pinnati) wurden durch den Menschen stark überformt. Abschließend diskutiert wird die zukünftige Entwicklung der Waldlichtungen mit Trockenrasen.
Wenig bekannte Trockenrasen-Gesellschaften in den Flußtälern am Südostrand der Böhmischen Masse
(1997)
Drei wenig bekannte Festuco-Brometea-Gesellschaften aus den kristallinen Tälern der Flüsse Krems, Kamp, Thaya/Dyje, Rokytná, Jihlava, Oslava und Svitava (Südostrand der Böhmischen Masse, Österreich und Tschechische Republik) werden beschrieben. Sie kommen teilweise auf den natürlichen Waldlichtungen südexponierter Felskanten vor, teilweise auch auf sekundären Standorten. Das Inulo oculi-christi-Stipetum pulcherrimae Vicherek et Chytrý in Chytrý et Vicherek 1996 (Festucion valesiacae) ist ein Trockenrasen basischer Böden, vor allem über Marmor und permokarbonischem Konglomerat in wärmeren Teilen des Untersuchungsgebietes. Das Genisto tinctoriae-Stipetum joannis ass. nova (Festucion valesiacae) ist ein Trockenrasen, der das Inulo oculi-christi-Stipetum pulcherrimae in kühleren und niederschlagsreicheren Lagen ablöst. Sein Vorkommen ist auf Amphibolit, Marmor und Kalkstein konzentriert. Das Centaureo stoebes-Allietum montani ass. nova (Alysso-Festucion pallentis) ist ein relativ offener Trockenrasen der von beständiger Bodenerosion beeinflußten Felsterrassen auf verschiedenen (meistens basischen) Gesteinen.
Es wird ein Überblick über Kalkmagerrasen- und Felsband-Gesellschaften im thüringischen Teil des mittleren Werratals gegeben. Auf steilen und größtenteils primär waldfreien Standorten sind vor allem Sesleria varia-reiche Kalkmagerrasen (Seslerio-Xerobromenion, Seslerio-Mesobromenion) ausgebildet, deren unterschiedliche floristische Zusammensetzung von der Höhenlage sowie von der Dynamik und Gründigkeit der Böden bestimmt wird. Ausschließlich als Ersatzgesellschaft von Kalkbuchenwäldern, meist durch Beweidung entstanden, kommt das Gentiano-Koelerietum (Eu-Mesobromenion) vor, das in drei edaphisch bedingte Subassoziationen gegliedert werden kann. Im Kontakt zu den Kalkmagerrasen stehen an besonders steilen, südlich exponierten Felsabbrüchen oft Festucion pallentis-Bestände.
Auf den glazifluvialen Hügeln der Masurischen und Litauischen Seenplatten im Bereich des Pommerschen Stadium der Weichselvereisung wurden die Rasen-Gesellschaften untersucht. Es ergaben sich 4 Vegetationseinheiten auf Grund der pflanzensoziologischen und bodenkundlichen Angaben, die zu den Sand-Trockenrasen bzw. Trockenwiesen gehören. Als neue Sandtrockenrasen-Gesellschaft wird die Acinos arvensis-Poa compressa-Ges. beschrieben. Außerdem lassen sich eine Sandtrockenrasen-Rumpfgesellschaft (Amerion elongatae), eine Arrhenatherion-Rumpfgesellschaft und eine Übergangsgesellschaft zwischen den Sandtrockenrasen und trockenen Wiesen erkennen. Die untersuchten Einheiten werden mit nahe verwandten aus umliegenden Gebieten verglichen; hieraus ergibt sich die Eigenart der Vegetation im Bereich der Masurischen und Litauischen Seenplatten.