Blue grass eyrie sedge lawn

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The blue grass Horstseggenrasen (Seslerio-Semperviretum) is an association (plant society) of the plant sociological association Alpine blue grass lawn ( Seslerion albicantis ). It is the typical plant community of steep alpine lawns on calcareous rock rubble as the subsoil. The two most important plant species are the lime blue grass ( Sesleria albicans , syn. Sesleria caerulea ) and the eyrie sedge ( Carex sempervirens ). Their rhizomes , i.e. their underground parts of the shoot, form a dense network that holds the unstable soil together. However, this network still leaves enough space for other species of this rich plant community.

In the succession, the blue grass Horstseggenrasen follows the limestone scree . This is initially devoid of soil and vegetation, but is gradually being populated by pioneer plants such as silver arum ( Dryas octopetala ) or trellis willow (e.g. Salix reticulata ). Gradually, the overgrown patches merge to form a closed lawn, which is gradually populated by the typical species of the blue-grass eyrie grass.

Site conditions

The typical altitude distribution is between 1900 and 2800  m above sea level. NN blue grass eyrie grasses are relatively warmth-loving. They are mainly found in sun-exposed locations with a relatively short snow cover of 5–6 months. Since the snow melts early, the melt water usually does not last through the summer. Therefore one observes adaptations of the plants, which reduce the evaporation and thus the water requirement (hairiness, thickened epidermis ). The soil is a browned rendzina with a pH around 6.5 ( humus carbonate soil ). The dark color of the humus causes strong local heating of the soil. In this steep position and on the loose subsoil, the soil is in a constant, slow downward flow movement ( solifluction ). As a result, the dense rhizome network tears open in strips and exposes erosion gaps, which are colonized by numerous herbs. The typical step-like structure of the blue-grass eyrie grass is formed. On the other hand, the lawn receives a constant influx of new limestone rubble from the weathered rocks above. That is why the soil always remains carbonate.

Species composition (examples)

Such a lawn often contains over 50 types of plants , significantly more than the meadows in the lowlands . Many are typical pointer plants of calcareous soils .

Some typical species in the Swiss Alps are:

literature

  • Introduction: Reisigl, H., Keller, H. 1994: Alpine plants in the habitat. 2nd edition, Stuttgart.
  • Oberdorfer, E. (Ed.) 1993: South German Plant Societies, Vol. 2, Stuttgart.
  • Distribution in the internship area: Berchtesgaden National Park, research reports 44.