Classification of the Sieversio montanae-Nardetum strictae in a cross-section of the Eastern Alps

摘要

The Sieversio montanae-Nardetum strictae 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 relevcbs 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 pratensis, 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.