Classification of the Sieversio montanae-Nardetum strictae in a cross-section of the Eastern Alps Christian Lu ¨th • Erich Tasser • Georg Niedrist • Josef Dalla Via • Ulrike Tappeiner Received: 21 April 2009 / Accepted: 15 June 2010 Ó Springer Science+Business Media B.V. 2010 Abstract The Sieversio montanae-Nardetum stric- tae is one of the most widespread plant communities in (sub-) alpine regions of the Alps. Our study examines the composition, ecology and distribution of this plant community in the Eastern Alps and addresses the issue of how the community is to be classified in the phytosociological system of Nardus- rich grasslands. Therefore, 357 vegetation releve ´s were taken from the literature and 115 from our own inventories were recorded from 2005 to 2007 in Western Austria (mostly Tyrol) and Northern Italy (mostly South Tyrol). Additionally, indicator values of Ellenberg and land-use information were used to help better interpret the ecological site conditions of the subgroups. The HCA revealed there the existence of four groups of the Sieversio montanae-Nardetum strictae, which were classified to subassociations: (1) typicum, (2) vaccinietosum, (3) trifolietosum praten- sis, and (4) seslerietosum albicantis. Besides the specific plant composition, altitude specifies the first, land-use intensity the second and third, and the pH of the topsoil the fourth subassociation. For the Eastern Alps, the plant community of the Sieversio montanae- Nardetum strictae should now be reclassified in the order of Nardetalia and the class of Calluno-Ulicetea. Finally, this plant community can be further classified by using the four above-mentioned subassociations. Keywords Indicator values  Indicator species  Differential species  Subassociation  Land-use types  European Alps Abbreviations ANOVA Analysis of Variance a.s.l. Above sea level DA Discriminant analysis EIV Ellenberg indicator values HCA Hierarchical cluster analysis ISA Indicator Species Analysis Introduction Nardus-rich grasslands result from lightly used pas- tures or meadows (Peppler 1992). In central Europe, because of preindustrial low land use (Peppler- Lisbach and Petersen 2001), such grasslands were most common and were to be found from forest-free lowlands up to high alpine regions (Preising 1949). However, since the second half of the twentieth century, due to intensification of land use in favorable C. Lu ¨th  U. Tappeiner (&) Institute of Ecology, University of Innsbruck, Sternwartestraße 15, 6020 Innsbruck, Austria e-mail: Ulrike.Tappeiner@uibk.ac.at E. Tasser  G. Niedrist  U. Tappeiner Institut for Alpine Environment, European Academy of Bolzano/Bozen, Drususallee 1, 39100 Bozen, Italy J. Dalla Via Research Centre for Agriculture and Forestry Laimburg, Laimburg 6, 39051 Pfatten, Italy 123 Plant Ecol DOI 10.1007/s11258-010-9807-9