Yazar "Dembicz, Iwona" seçeneğine göre listele
Listeleniyor 1 - 2 / 2
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe The Eurasian Dry Grassland Group (EDGG) in 2018-2019(Sciendo, 2019) Dengler, Jürgen; Aleksanyan, Alla; Ambarlı, Didem; Biurrun, İdoia; Dembicz, Iwona; Kuzemko, Anna A.; Vrahnakis, MichaelThis report summarises the activities and achievements of the Eurasian Dry Grassland Group (EDGG) from January 2018 through July 2019. During the reported period, two Eurasian Grassland Conference (EGCs) took place: the 15th EGC in Sulmona, Italy, and the 16th EGC in Graz, Austria. The 11th and 12th EDGG Field Workshops studied vegetation diversity patterns in the inner alpine valleys of Austria and Switzerland, while the 13th Field Workshop was organised in Armenia. The formerly electronic newsletter of EDGG (Bulletin of the Eurasian Dry Grassland) was transformed into a peer-reviewed international journal, called Palaearctic Grasslands, which now is attracting both scientific and photographic contributions. Furthermore, the EDGG homepage was re-constructed with a new design and content management system. The EDGG has also finalised two grassland-related Special Features during the past 1.5 years in the international journals Tuexenia and Hacquetia, and contributed with eight chapters to the book Grasslands of the World: Diversity, Management and Conservation. The vegetation-plot database GrassPlot, containing standardised multi-scale data from Palaearctic grasslands and closely connected with EDGG, has developed well, as did some other regional and national grassland-focused databases. © 2019 Jürgen Dengler et al., published by Sciendo.Öğe Grasslands of Navarre (Spain), focusing on the Festuco-Brometea: classification, hierarchical expert system and characterisation(Pensoft Publishers, 2021) García-Mijangos, Itziar; Berastegi, Asun; Biurrun, Idoia; Dembicz, Iwona; Janišová, Monika; Kuzemko, Anna; Vynokurov, DenysAims: To clarify the syntaxonomic position of the grasslands in Navarre, with special focus on the dry grasslands, and to characterise the resulting syntaxonomic units in terms of diagnostic species and ecological conditions. Study area: Navarre (northern Spain). Methods: We sampled 119 plots of 10 m2 following the standardised EDGG methodology and analysed them together with 839 plots of similar size recorded in the 1990. For the classification, we used the modified TWINSPAN algorithm, complemented by the determination of diagnostic species with phi coefficients of association, which led to the creation of an expert system. We conducted these steps in a hierarchical manner for each syntaxonomic rank. We visualised the position of the syntaxa along environmental gradients by means of NMDS. Species richness, and structural and ecological characteristics of the syntaxa were compared by ANOVAs. Results: We could clearly identify five phytosociological classes: Lygeo-Stipetea, Festuco-Brometea, Molinio-Arrhenatheretea, Nardetea strictae, and Elyno-Seslerietea. Within the Festuco-Brometea a xeric and a meso-xeric order could be distinguished, with two alliances each, and eight associations in total: Thymelaeo-Aphyllanthetum, Jurineo-Festucetum, Helianthemo-Koelerietum, Prunello-Plantaginetum, Carduncello-Brachypodietum, Helictotricho-Seslerietum, Calamintho-Seselietum and Carici-Teucrietum. Conclusions: The combination of numerical methods allowed a consistent and more objective classification of grassland types in Navarre than previous approaches. At the association level, we could largely reproduce the units previously described with traditional phytosociological methods. By contrast, at higher syntaxonomic level, our analyses suggest significant modifications. Most importantly, a major part of the units traditionally included in the Festuco-Ononidetea seem to fall within the Festuco-Brometea. We could show that bryophytes and lichens are core elements of these grasslands and particularly the Mediterranean ones of Lygeo-Stipetea, both in terms of biodiversity and of diagnostic species. We conclude that the combination of our different numerical methods is promising for deriving more objective and reproducible delimitations of syntaxa in a hierarchical manner. Copyright Itziar García-Mijangos et al.