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Inland sand vegetation, in our case steppic sandy grassland on base-rich soils, is highly endangered in Europe and therefore in the focus of restoration ecology. While there are studies which deal with short-term restoration success, results for an extended time are rare. We were able to analyse the success of a three-step restoration measure for 10 years.
The experiment was established on an exarable field in the Upper Rhine valley, Hesse, Germany. The three-step restoration approach comprised 1) abiotic restoration by deep-sand deposition, 2) inoculation with raked/mown plant material from two different donor sites with well-developed Koelerion glaucae/Allio-Stipetum vegetation and 3) low-intensity grazing by donkeys. The vegetation of the restoration and donor sites (also serving as reference sites to assess restoration success) was sampled on six permanent plots, respectively. Data analyses included ordination, classification and target-species ratios (TSR: relation of target species to all species).
Detrended correspondence analysis revealed a continuous succession of the restoration plots towards the corresponding reference plots: open soil decreased, ruderal species declined and target species increased. While speed of succession decreased, there was still a further improvement in the tenth year. The qualitative TSR (number of target species) reached a plateau after the sixth year with values only slightly lower than at the reference sites. The quantitative TSR (cover of target species) showed a steady improvement and even excelled one reference site. Koelerion glaucae species were present with constancy 17–67% since the 3rd year, with 33–100% since the 7th year. It does not completely resemble either reference site due to a mixture of propagules of both donor sites (e.g. by wind and donkeys) and input from the surroundings. Already in the first year, three Red-list species established themselves, since the 8th year 23 Red-list/near-threatened species have been present. Some ruderal species colonised the restoration site and occurred permanently.
Additionally, we studied the establishment of the highly threatened species Bassia laniflora after inoculation for 6–12 years on three further plots adjacent to the other ones. One of these plots was located on a former sandy field without abiotic restoration; two other plots represented typical Koelerion glaucae vegetation on a newer deep-sand deposition. Bassia laniflora established itself well on all plots. We conclude that restoration of steppic sandy grassland, including highly threatened species, was not only permanently, but increasingly successful over a time span of 10 years. Management by grazing, however, will remain essential to suppress ruderalisation.
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.
A phytosociological survey of weed (segetal) vegetation in Slovakia was performed. A total of 508 relevés were sampled in 2002–2008. The aims of this study were to determine the actual distribution of the segetal communities, to analyze their floristic structure, and to evaluate their relationships to selected environmental factors. Thirteen plant communities of the class Stellarietea mediae were distinguished by cluster analysis; 11 communities were included in the subclass Violenea arvensis (Lathyro tuberosi-Adonidetum aestivalis, Consolido-Anthemidetum austriacae, Euphorbio exiguae-Melandrietum noctiflori, Veronicetum trilobae-triphyllidi, Lamio amplexicauli-Thlaspietum arvensis, Taraxacum sect. Ruderalia community, Spergulo arvensis-Scleranthetum annui, Myosotido-Sonchetum arvensis, Echinochloo-Setarietum pumilae, Galinsogo-Setarietum, and Stachyo annui-Setarietum pumilae) and two in the subclass Sisymbrienea (Portulacetum oleraceae and Setario viridis-Erigeronetum canadensis). Communities were characterized by diagnostic, constant, and dominant species and their structure, ecology, and distribution were estimated. The species composition of these communities was documented in synoptic and association tables. DCA ordination and analysis of variance was used to determine the main environmental factors of floristic differentiation and to determine ecological and structural differences among the communities. The analyses showed that the most important factors affecting floristic composition and classification of the weed communities are their time of development (agroecophase), the type of crops and altitude.
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.
Die Steppenrasen des NSG „Badraer Lehde–Großer Eller“ werden hier erstmalig beschrieben und analysiert. 156 Originalaufnahmen wurden über eine Clusteranalyse in sieben Assoziationen und zwei ranglose Gesellschaften innerhalb der Verbände Alysso-Sedion, Seslerio-Festucion pallentis, Festucion valesiacae, Xerobromion und Cirsio-Brachypodion gegliedert. Die Auswertung alter Luftbilder zeigt, dass die beiden ranglosen Gesellschaften junge Steppenrasen auf ehemaligen Ackerflächen darstellen, während die Assoziationen überwiegend alte Steppenrasen repräsentieren. Der erste floristische Gradient nach einer NMDS in der Vegetation wird durch Variablen erklärt, die die Temperatur und die Wasserversorgung der Standorte anzeigen. Der zweite floristische Gradient kann durch das Alter der Flächen erklärt werden. Alte Steppenrasen enthalten signifikant mehr gefährdete Pflanzenarten als junge Steppenrasen, während sich der Gesamtartenreichtum zwischen jungen und alten Beständen nicht signifikant unterscheidet. Ein CSR-Strategietypenspektrum zeigt in einer Gesellschaft auf ehemaligen Ackerflächen eine höhere Bedeutung der C-Strategie, sonst aber kaum Unterschiede zwischen den Syntaxa. Die beiden Xerobromion-Assoziationen sind besonders artenreich und enthalten überdurchschnittlich viele gefährdete Pflanzenarten. Eine Gesellschaft auf ehemaligen Ackerflächen enthält durchschnittlich viele und die andere fast keine gefährdeten Arten. Der Artenreichtum der Gefäßpflanzen ist am stärksten positiv mit der Bodengründigkeit, der Deckung der Krautschicht und dem Ellenberg-Zeigerwert für Bodenreaktion und negativ mit dem Zeigerwert für Temperatur korreliert. Unsere Studie zeigt die hohe Bedeutung des NSG für den Trockenrasenschutz. Diese beruht vor allem auf der allgemein hohen Artenvielfalt und Diversität an Gesellschaften sowie auf der sehr hohen Zahl gefährdeter Arten.
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.
In Folge von Eindeichung, Eintiefung und Staustufenbau sind an der Donau zwischen Neuburg und Ingolstadt auentypische Überschwemmungen und Grundwasserstandsschwankungen weitgehend verloren gegangen. Die wasserbauliche Redynamisierung wird durch ein umfassendes auenökologisches Monitoring begleitet. Um die Reaktion der Waldvegetation auf Änderungen des Wasserregimes und der Morphodynamik zu beobachten, wurden im Projektgebiet 117 Dauerbeobachtungsflächen (DBF) angelegt und vor Maßnahmenbeginn aufgenommen. Eine Auswertung der Baseline-Aufnahmen hinsichtlich der Waldgesellschaften ergab, dass bergahornreiche Auenfolgegesellschaften und eschenreiche Hartholzauen unterschiedlichen Wasserhaushalts dominieren, während Weichholzauen nicht mehr anzutreffen sind. Der mittels DCA ermittelte floristische Hauptgradient lässt sich sehr gut durch den modellierten Grundwasserstand und die in den DBF gemessene Bodenfeuchte erklären. Ellenberg-Zeigerwerte deuten auf die Bedeutung des Wasserhaushaltes, der Belichtung und der Nährstoffversorgung für die Zusammensetzung der Bodenvegetation hin, die mit weiteren Analysen (Nährstoffanalyse) quantifiziert werden soll. Die Untersuchungen liefern wichtige Grundlagen für eine modellhafte Vorhersage der erwarteten Effekte der wasserbaulichen Maßnahmen.
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.
Wir untersuchten den Einfluss der Umwelt und Landnutzung auf die Vegetation artenreicher Wiesen und Weiden im nordwestdeutschen Mittelgebirgsraum in Südniedersachsen. In drei Teilgebieten (Ith, Rühler Schweiz, und Wangelnstedter Berge) wurden 152 Vegetationsaufnahmen von artenreichen Wiesen und Weiden erstellt und für jede Aufnahmefläche der pH-Wert, die Meereshöhe, Hanglage, Hangneigung, Ellenberg-Zeigerwerte für Nährstoffe, Feuchte, Reaktion und Temperatur, Nutzungswertzahlen nach Briemle sowie die aktuelle Landnutzung bestimmt. Die meisten Bestände im Ith und in den Wangelnstedter Bergen stellen magere Glatthaferwiesen des Arrhenatheretum ranunculetosum dar. In der Rühler Schweiz kommen vor allem magere Kammgrasweiden des Cynosuro-Lolietum luzuletosum vor. Magere Grasländer auf mäßig sauren Böden wurden als Borstgrasrasen des Polygalo-Nardetum sowie Rotschwingelrasen innerhalb der Arrhenatheretalia klassifiziert. Die floristischen Hauptgradienten in der Vegetation sind mit Variablen, die die Nährstoffversorgung der Standorte anzeigen, aber auch mit dem pH-Wert des Bodens und der Bodenfeuchte eng korreliert. Die Meereshöhe der Flächen (130–385 m ü. NN) hat nur einen mäßigen Einfluss auf die Variation der Vegetation, ist aber für das Vorkommen mehrerer Montanzeiger wichtig. Der Pflanzenartenreichtum der Grasländer ist positiv mit der Hangneigung der Flächen und dem pH-Wert des Bodens und negativ mit den Zeigerwerten für Nährstoffe und Feuchte korreliert. Die Nutzungswertzahlen zeigen bei Borstgrasrasen niedrige und sonst hohe Pflegebedürftigkeit. Hohe Trittzahlen der Glatthaferwiesen können auf ihre Nutzung als Extensivumtriebsweide zurückgeführt werden. Anscheinend eignet sich diese Nutzungsform in Untersuchungsgebiet zum Erhalt magerer Wiesen.
Die Saumgesellschaften im Osten Österreichs sind bisher nur sehr unzureichend dokumentiert. Ziel dieser Arbeit war die möglichst vollständige Erfassung der floristisch und standörtlichen Variationsbreite der Säume auf magerern Standorten im Biosphärenpark Wienerwald. Der Wienerwald ist eines der größten naturnahen Laubwaldgebiete der collinen bis submontanen Stufe in Mitteleuropa. Er liegt am Übergang vom subatlantisch bestimmten mitteleuropäischen zum pannonischen Klima. Auf der Basis von 132 neu erhobenen Vegetationsaufnahmen wurde eine TWINSPAN-Klassifikation durchgeführt. Die Korrelation der standörtlichen Parameter mit der Artenzusammensetzung wurde in einer kanonischen Korrespondenzanalyse (CCA) analysiert. Zur syntaxonomischen Interpretation wurden auch Aufnahmen aus der Literatur hinzugefügt. - Im Gebiet am weitesten verbreitet ist der Verband Trifolion medii. Gesellschaften des Verbandes Geranion sanguinei sind im Vergleich dazu seltener und bevorzugen die warmen Randlagen des Wienerwaldes. Es werden einige Probleme in der syntaxonomischen Gliederung der beiden Verbände diskutiert.