Semi-ruderal dry grassland

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Semi- ruderal dry grasslands are plant communities on dry ruderal areas (dry pastures and turf), which mainly consist of sweet grasses and other herbaceous plants .

The semi-ruderal dry grasslands are an expression of the “ruderal meadows” on warm, dry locations. Ruderal meadows form grass-dominated, grassland-like vegetation stands that are not used for agriculture, but arise as a by-product of other uses or maintenance measures. They are typically found e.g. B. on roadsides, on embankments and embankments and in other places that are regularly mowed or cut without the intended use of the vegetation. They can also arise as succession stages when settling areas free of vegetation. While the ruderal meadows in fresh locations usually resemble fat meadows in terms of their combination of species, into which ruderal tall perennials are sprinkled, those in particularly warm and dry locations are floristically more independent. Corresponding populations can only be found optimally under continental or subcontinental climatic conditions.

In the plant-sociological system, the semi-ruderal dry grassland is described as a plant-sociological association ( Artemisio-Agropyrion intermedii Müller / Görs 1969). Many vegetation watchers that emphasize the autonomy especially, put them in the order Agropyretalia intermedii-repentis in the class of Agropyretea intermedii-repentis which in addition to the Halbruderalen dry grassland nor the Halbruderalen chalk grasslands ( Convolvulo-Agropyrion repentis covers). Other authors assign them to the perennial ruderal corridors ( Artemisietea ) because of numerous common species .

In the societies, the replacing Agropyron species, common couch grass ( Agropyron repens ) or gray-green couch grass ( Agropyron intermedium ) dominate. In addition, ruderal species and types of limestone dry and semi-dry grassland (Festuco-Brometea) occur as a rule.

Species-rich meadows belong to the so-called FFH biotopes and actually enjoy special protection under EU law ( Natura 2000 ). The ruderal dry grasslands are not protected by this

In the meadow type, besides the couch grass species, bindweed Convolvulus arvensis and wormwood Artemisia absinthium often dominate . Ecologically, the stocks are located between the steppe-like dry grasslands ( Stipo-Poion ) and ruderal grasslands ( Agropyretalia repentis ). In Switzerland, ruderal dry grasslands occur particularly in the inner Alpine dry valleys, as well as in warm, dry areas in Ticino and along the southern foot of the Jura ( Geneva ), in Schaffhausen's Randen and Hegau near the border and Basel-Stadt . In Germany one finds correspondingly classified stocks especially in the central German dry area.

The plant community quickly opens up abandoned fields or open areas in extremely dry grassland (cracks in the ground, pasture steps). This shows the typical property of the couch grass of quickly covering larger areas of the earth with their foothills. The characteristic species of the Stipo-Poion and Agropyretalia are always joined by drought-bearing ruderal species, which focus on the Onopordetalia ( xerothermal ruderal communities with many biennial species). Stocks in which ruderal species achieve more than 50% coverage are not counted here. Also stocks in which species of the subcontinental dry grass ( steppe grass of the association Cirsio-Brachypodion ) are strongly represented are not included.

Semi-rudimentary dry lawns are interpreted differently in plant sociology. The one in Mucina at al. Comes closest to the Swiss stocks. (1993) stated Agropyro-Artemisietum, which is assigned to the Stipo-Poion association there. The definition according to Eggenberger et al. (2001) also includes societies of the semi-ruderal semi-arid grassland ( Convolvulo-Agropyrion ).

Typical types of society:

Switzerland

Evaluation of the national mapping of dry meadows and dry pastures : So far (before the mapping of the VS), societies of semi-ruderal dry grasslands were only rarely found. Since the main distribution is in the regions of Engadin and VS, which have not yet been mapped, the numbers will change. The species-rich semi-brutal dry grassland is considered to be of above-average value in terms of nature conservation.

Occurrence of semi-rudimentary dry areas

frequency

  • 0.1% of the recorded areas
  • 1% of the listed objects
  • 16 answers absolutely

The main types of vegetation are:

  • 25% real semi-ruderal dry grass with at least 6 species from the species group.
  • 50% - transitions to steppe grass (Stipo-Poion), species of this group dominate, v. a. Festuca valesiaca
  • 25% - transitions to semi- arid grassland (mesobromion), species of this group dominate, v. a. Bromus erectus .

Use: From the previous figures it can already be concluded that the company is only mowed in exceptional cases. Sometimes the areas are grazed extensively with sheep, but mostly they lie fallow.

  • Meadows 5%
  • Pastures 40%
  • Fallow 55%

literature

  • Stefan Eggenberg, Thomas Dalang, Michael Dipner, Cornelia Mayer: Mapping and evaluation of dry meadows and pastures of national importance. Technical report. In: Environmental Series, Volume 325, Federal Office for the Environment, Forests and Landscape, Bern 2001.
  • Raymond Delarze, Yves Gonseth, Pierre Galland: Habitats in Switzerland: Ecology - Endangerment - Identifiers. Ott, Thun 1999, ISBN 3-7225-6749-1 (as Convolvulo-Agropyrion (4.6.1)).
  • Heinz Ellenberg : Vegetation of Central Europe with the Alps in an ecological, dynamic and historical perspective (=  UTB for science. Large series . Volume 8104 ). 5th, heavily changed and improved edition. Eugen Ulmer, Stuttgart (Hohenheim) 1996, ISBN 3-8252-8104-3 . (as Artemisio absinthii-Elymion)
  • Erich Oberdorfer: South German plant communities. Part II. Sand and dry grasslands, heather and bristle grass societies, alpine grasslands, fringing societies, field and tall herbaceous corridors. 2nd edition Gustav Fischer, Jena / Stuttgart / New York 1978, ISBN 3-437-30282-5 (as Artemisio-Agropyrion intermedii)
  • Ladislav Mucina, Georg Grabherr, Thomas Ellmauer (eds.): The Austrian plant associations. Part 1: Anthropogenic Vegetation. Gustav Fischer, Jena / Stuttgart / New York 1993, ISBN 3-334-60452-7 (complete works), pp. 192-202. (as Agropyro-Artemisietum and Convolvulo-Agropyrion)
  • Pierre Devillers, Jean Devillers-Terschuren, Jean-Pierre Ledant: Corine biotopes manual. Habitats of the European Community. A method to identify and describe consistently sites of major importance for nature conservation. European Communities, Luxembourg 1991, ISBN 92-826-3228-8 (as ruderal communities (87))
  • Michael Dipner-Gerber, Gaby Volkart et al. (2010): Dry meadows and pastures of national importance. Implementation aid for the Dry Meadow Ordinance. Environmental Implementation No. 1017, FOEN Federal Office for the Environment, Bern. 83 pages. PDF .

Individual evidence

  1. ^ Theo Müller, Sabine Görs: Halbruderale dry and semi-dry lawns. In: Vegetatio. Volume 18, No. 1-6, 1969, pp. 203-221, doi: 10.1007 / BF00332836 .
  2. ↑ European Commission DG Environment: Interpretation Manual Of European Union Habitats - EUR27. 2007, PDF file.
  3. ^ Stefan Eggenberg, Thomas Dalang, Michael Dipner, Cornelia Mayer: Mapping and evaluation of dry meadows and pastures of national importance. Technical report. In: Environmental Series, Volume 325, Federal Office for the Environment, Forests and Landscape, Bern 2001.
  4. ↑ Michael Dipner-Gerber, Gaby Volkart et al. (2010): Dry meadows and pastures of national importance. Implementation aid for the Dry Meadow Ordinance. Environmental Implementation No. 1017, FOEN Federal Office for the Environment, Bern. 83 pages. PDF