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2018. május 31., csütörtök

27th Congress of the European Vegetation Survey

Május 23. és 26. között rendezték a 27. EVS kongresszust, amely a vegetációosztályozással és a vegetációtípusok védelmével foglalkozó kutatók éves találkozója. A konferenciasorozat korábbi eseményeiről már írtam itt és itt. A helyszín ezúttal éppen Wroclaw volt, és a szervezői/előkészítői munkában is némi részt vállaltam. Annál kisebb ez a rész, hogy öndicséretnek minősüljön leírnom, hogy az egyik legjobban megszervezett konferencia volt az idei a sorozatban azok közül, amelyre ellátogattam.  Minden flottul ment, a konferenciacsomag 20x-os lupét és speciális kivitelű édességeket rejtett, a péntek esti konferenciavacsorát pedig az Oderán hajózva töltöttük. :) Ezúton is gratulálok a kollégáimnak, akik mindent megtettek azért, hogy sikerüljön.



A 'Classification and Database Management II' szekcióban előadásban számoltam be a Polonez projektes kutatásom első eredményeiről, az előadás absztraktja alább olvasható.

Lengyel, A., Swacha, G. & Kącki, Z.: Trait-based numerical classification of Molinio-Arrhenatheretea grasslands in Poland

Descriptive vegetation science has witnessed a rapid progress in the last decades due to the improvement of broad-scale electronic databases. Most synthetic works aimed at delimiting vegetation types on the basis of numerical analysis of species composition of sample plots. Such classifications are often supposed to serve as a multi-purpose reference of habitat types, since the diversity and composition of natural communities are known to determine general ecosystem properties. However, it has been recognised that focusing on species composition may fail to reveal certain patterns of vegetation that are strongly linked with the functioning of ecosystems. Instead of the taxonomic identities of species, their functional traits could offer more relevant information. Functional classifications are expected to have more general validity than species-based classifications because often the same traits respond to the same environmental gradients in very different places of the world due to convergent evolution. In contrast, species are dispersal-limited, thus their local abundances are informative only within their respective distributional limits. Our aim was to classify managed herbaceous vegetation on deep soils and temperate climate of Molinio-Arrhenatheretea syntaxonomical class in Poland on the basis of phytosociological relevés, plant trait data, and using numerical methods.
19995 vegetation plots representing all major grassland types of Poland were retrieved from the Polish Vegetation Database, from which a narrower subset of cca. 6000 Molinio-Arrhenatheretea relevés were resampled. Records of specific leaf area, canopy height, seed mass, clonality and bud bank were obtained from the LEDA and CLO-PLA databases. Between-plot dissimilarities were expressed by Rao functional dissimilarity index. The dissimilarity matrix was passed to principal coordinates ordination, and its most important axes were classified by Ward’s method. Although, this classification did not reproduce the hierarchy of the syntaxonomical categories at a coarse scale, at finer resolutions the main subtypes of Molinio-Arrhenatheretea were differentiated: mesic and wet hay meadows and pastures, marshes and wet grasslands rich in sedges, tall-forb vegetation, and trampled grasslands. After the first promising results, more subtle differences between types in individual traits are subject to further research.



Egy további előadás társszerzőjeként is szerepeltem:

Willner W., Roleček J., Dengler J., Chytrý M., Janišová M., Lengyel A., Aćić S., Becker T., Demina O., Jandt U., Kącki Z., Krstivojević-Čuk M., Korolyuk A., Kuzemko A., Kropf M., Lebedeva M., Semenishchenkov Y., Šilc U., Stančić Z., Staudinger M., Poluyanovm A., Vassilev K. & Yamalov S.: Syntaxonomic revision of the semi-dry grasslands of Central and Eastern Europe

The Eurasian semi-dry grasslands are among the most species-rich and most valuable habitat types of the northern hemisphere. For our syntaxonomic revision, we used a dataset of 34,173 plot records which were assigned to the class Festuco-Brometea by the EuroVegChecklist expert system. In the first step, we classified the dataset into orders and alliances. As starting point, a TWINSPAN classification of the whole dataset was done and the diagnostic species of the main clusters (first and second division level) were determined. The plots were re-assigned using formal definitions of the orders, and then the subset of the order Brometalia erecti (=Brachypodietalia pinnati), corresponding to all semi-dry grasslands of the study area, was classified again. On the basis of this second TWINSPAN classification, formal definitions of the alliances were established. We distinguished the following alliances: Bromion erecti s.str. (=Mesobromion), Cirsio-Brachypodion pinnati (incl. Fragario-Trifolion montani, Agrostio-Avenulion schellianae, Scabioso ochroleucae-Poion angustifoliae, Adonido vernalis-Stipion tirsae), Scorzonerion villosae and Chrysopogono-Danthonion. The fifth alliance “Koelerio-Phleion phleoidis” is transitional towards the class Koelerio-Corynephoretea and its status needs further study.
We also established formal definitions of all associations of the Bromion erecti and Cirsio-Brachypodion pinnati within the study area. The other alliances were not further classified in the present study. Associations were identified using (i) the TWINSPAN classification of the whole order, (ii) TWINSPAN classifications of regionally restricted data sets (typically all Brometalia plots of one country) and (iii) existing national classification schemes. All formal definitions were written in the expert system language of the JUICE program.



Összesen kb. 180 résztvevő érkezett, ha jól emlékszem, kb. 20 országból. A konferencia programját és absztraktjait tartalmazó weboldal itt érhető el.

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