Ferrantia 66 Die Graslandgesellschaften Luxemburgs

S. Schneider Die Graslandgesellschaften Luxemburgs
Trespen-Halbtrockenrasen, Goldhaferwiesen und
artenreichen Glatthaferwiesen. Des Weiteren sind
die Kleinseggenriede, Großseggenriede und artenreichen
Feuchtwiesen sowie deren Brachestadien
in Luxemburg gefährdet. Einzelne Graslandgesellschaften
sind nur noch in Naturschutzgebieten
gut erhalten. Die naturschutzfachliche
Bewertung umfasst allgemein gültige Nutzungsund
Pflegeempfehlungen, die zum Erhalt der
selten werdenden Graslandgesellschaften und
ihrer Flora beitragen sollen.
Die vorliegende vegetationskundliche Bearbeitung
der Graslandvegetation soll als Grundlage für
naturschutzfachliche Planungen dienen.
7. Summary
The present work gives a first overview on the
plant communities of the grassland of Luxembourg
by typing, classifying and describing them
comprehensively.
The phytosociological classification is based on 793
vegetation relevés from 25 unpublished works of
the last 35 years as well as on 413 relevés recorded
in the years 2006 to 2009, whereby these current
data mostly document nutrient-poor meadows.
Degraded vegetation stands lacking characteristic
species as well as transition communities were
included beyond well minted ones in order to
reflect the current variety of grassland.
The phytosociological evaluation resulted in
altogether 31 plant communities. The floristic
classification of the grassland communities in
units and variants follows primarily ecological
gradients of nutrient, acidity and water supply as
well as type and intensity of agricultural land use.
The subunits are characterized on the basis of the
respective group of differential species and their
location requirements. In the 21 vegetation tables
the diagnostic species of the grassland communities
as well as their differentiating species
groups are identified.
The majority of the vegetation units belong
syn-systematically to the class Molinio-Arrhenatheretea
(cultivated meadows and related vegetation
types) with plant communities from the following
alliances: Calthion palustris, Molinion caeruleae,
Arrhenatherion elatioris, Polygono-Trisetion and
Ferrantia • 66 / 2011
Potentillion anserinae. Furthermore plant communities
of the Magnocaricion elatae, Caricion nigrae,
Bromion erecti and Violion caninae are described.
When describing grassland communities the
focus is mainly put on the species composition
regarding characteristic and diagnostic species.
Besides the various and remarkable flowering
aspects of grassland as well as their structural
characteristics are emphasized. Furthermore
the description contains information on the
current distribution of these plant communities
in Luxembourg. The grassland communities are
characterized regarding their conservation status
and protection value in Luxembourg as well as
classified regarding their protection status with
respect to the European Habitats Directive and
the current law of nature conservation of Luxembourg.
The protection value is evaluated among
other things on basis of rare and endangered
flowering plants as well as floristic rarities.
In addition to own results and observations, the
common stand of knowledge over the grassland
communities regarding their ecology, land use and
value for nature conservation based was collected
from literature and comprehensively inserted.
The syntaxonomic classification, the demarcation
of the plant communities as well as their naming
takes place critically, including supra-regional
monographs as well as German overviews.
The Calthion-alliance-community and the Arrhenatheretum
elatioris, which are especially well documented
by a huge number of relevés, take the emphasis
within the examined syntaxa, which subdivide
into a multiplicity of subunits. The False Oatgrass
meadows particularly exhibit a broad amplitude
regarding water, nutrient and base supply.
The demarcation and allocation of some grassland
communities proved to be difficult due to close
spatial mixing and to transitions towards ecologically
and floristically related syntaxa and were
thus in each case described in detail.
The geographical distribution of many grassland
communities can be attributed to the natural
conditions of Luxembourg, in particular regarding
geology and climate. While some plant communities
almost exclusively occur on the base-richer
substrates in the south (Gutland), others are found
only on the acidic grounds in the devonian north
(Ösling), belonging to the Rhenish Uplands.
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