Limestone grasslands

from Wikipedia, the free encyclopedia
flower-rich limestone grasslands on Walberg near Walburg (Werra-Meißner district, Northern Hesse)

Lean calcareous grasslands , alternatively also called dry calcareous grasslands , are extensively used, species- and flower-rich grasslands - or grassland - biotopes on soils rich in bases . In terms of their species composition, they are related to the steppes of Eastern Europe and Asia (the Eurasian steppe ), but were created in Central Europe with the support of people on locations that previously had forest (so-called semi - cultural formation ). Because of their special biodiversity and their threat from more intensive forms of use, limestone grasslands are a protected object of nature conservation . Bush-covered limestone grasslands are also called juniper heather .

Location

Lean lime grassland on the Swabian Alb (NSG Eichhalde )

The lack of nutrients, especially nitrogen and phosphorus, is typical of limestone grasslands . The soils are usually rich in lime, on limestone , dolomite or loess that has not been decalcified . On soils of other base-rich, but lime-poor rocks, transition stocks to the poor grasslands of acidic soils form (in terms of vegetation as silicate rock and sandy grasslands). These transitional stocks are rare because appropriate soils easily agriculturally meliorieren leave and therefore in the cultural landscape are hardly obtained. Lean-lime lawns mostly occur on shallow soils, often on a more or less steep slope, typical soil type here is a rendzina , with steppe lawns on loess often a black earth (Tschernosem). Depending on the characteristics and type, the soil is dry or with an average of medium water supply (fresh), but then usually with a pronounced dry period, which exposes the plants to increased drought stress at times. However, the nutrient, not the water content of the soil is decisive for the occurrence. With nitrogen fertilization, limestone grasslands can therefore be converted into meadows without water . Plants of the limestone grasslands are usually extremely light-needing and fail even with moderate shade, but few of their species are still found in the undergrowth of light forests, especially pine forests . This specialization was described by Ellenberg as a "light-loving hunger artist".

According to ecological measurements, the soil of a lean lime lawn only provides the plants with around 20 to 30 kilograms of nitrogen per hectare and year, this value is lower than in a beech forest in a comparable location. This is essentially based on the legumes that are mostly involved in the population . An important reason is, in addition to the mineralization inhibited by drought, the centuries of nutrient deprivation through human use. The stocks are therefore agriculturally poor and are usually listed as " wasteland " in the land registry . The annual hay harvest is 10, rarely up to 30 quintals per hectare and is hardly half as high as in fat meadows, even if the crops are sometimes quite high-grass. A considerable part of the growth of the plants is invested in the roots and is therefore not usable for humans and their cattle.

use

Depending on the type and the landscape, lime-lime lawns were traditionally mowed or grazed to make hay. While pasture is still used in some regions, agricultural mowing is hardly common today because the effort on the mostly steep slopes is high and the yield is low. Most of the areas are therefore maintained by nature conservation or managed by farmers, in return for compensation payments, under nature conservation requirements ( extensive grassland management , biotope grassland ).

vegetation

The calcareous grasslands include the phytosociological system in the class Festuco-Brometea. The further breakdown takes place according to the location (dry or fresh) and according to the region, with its respective climate. A distinction is made between the limestone grasslands of the suboceanic region (Western Europe) and the subcontinental region (Eastern Europe). The populations in the north and northeast (Baltic States, southern Scandinavia, for example the Alvare on Öland ) and those in southern Europe (Balkans and southern Alps) are different from each other and from the Central European ones. Several systems of classification are in use, some of which are clearly distinguishable stocks listed under the same name or certain names are only used nationally and given a different name in other countries. The system is therefore partly unclear and contradictory. The following presentation is based primarily on the conditions in Central Europe.

Trespen dry grass

Limestone grasslands are typical for north-western Central Europe and are called Trespentryrasen, after the characteristic grass species upright Trespe ( Bromus erectus ). In the phytosociological system they form the order Brometalia erecti (by some authors instead of nomenclatural reasons, the name Brachypodietalia pinnati, named after the Brachypodium pinnatum pinnatum Brachypodium , preferably). Further character species are, for example, common horseshoe clover Hippocrepis comosa , yellow sun rose Helianthemum nummularium agg. , Common wound clover Anthyllis vulneraria , Carthusian carnation Dianthus carthusianorum , common pasque flower Pulsatilla vulgaris .

  • Bromus erectus

  • Hippocrepis comosa

  • Helianthemum nummularium

  • Dianthus carthusianorum

  • Pulsatilla vulgaris

  • Anthyllis vulneraria

Depending on the dryness of the location, a distinction is made between a "real" or "fully dry grassland", Xerobrometum, in Germany only widespread in southern Germany, endangered (Red List 3) and a "semi-dry grassland", Mesobrometum or Brometum, highly endangered in Germany (Red List 2) .

Xerobrometum

The real Trespen dry grassland, the Xerobrometum, is bound to extremely dry, warm rock or gravel locations; geographically it only occurs in south-western Central Europe, in Switzerland, in Alsace, in the Upper Rhine Valley and in the western Swabian Alb. The sward has a gappy structure and there are numerous dwarf shrubs . In the gaps, besides lichens and mosses, there are widespread spring annuals . According to Oberdorfer Echte Kugelblume Globularia punctata , narrow-leaved flax Linum tenuifolium , common needle rose Fumana procumbens , blue-green fiber umbrella Trinia glauca , mountain germander Teucrium montanum belong to the character types .

  • Globularia punctata

  • Linum tenuifolium

  • Fumana procumbens

  • Trinia glauca

  • Teucrium montanum

Mesobrometum

The so-called semi-arid grasslands of the Mesobromion Association are much more widespread than the real Trespen dry grassland and occur in particular further north and west. The sward is almost always closed, the stand is taller and more meadow-like. The characteristic species include Downy meadow oats Helictotrichon pubescens , quaking grass Briza media , pigeon Scabious Scabiosa columbaria , seed sainfoin Onobrychis viciifolia , Bulbous Buttercup Ranunculus bulbosus , Rough Violet Viola hirta , Large-flowered Accentor Prunella grandiflora , Carlina vulgaris Carlina vulgaris , Meadow Clary Salvia pratensis (also in species-rich fat meadows lime), cowslip Primula Veris (also in forests lime). In Central Europe (formerly) grazed and mowed semi-arid grasslands are usually easily recognizable by the combination of species. While the Upright Brome missing the grazed grass, here are the grasses Brachypodium pinnatum and enter Great Schiller grass Koeleria pyramidata and a number of niedrigwüchsigen, thorny, prickly or poisonous pasture weeds out, including Cirsium acaule Cirsium acaule , German Frans gentian Gentianella germanica , Common Frans Enzian Gentianopsis ciliata and Crawling Restharrow Ononis repens . For it was their own association , the "Gentian Schiller Grass Lawn" (Gentiano-Koelerietum) distinguished. With the cessation of use ( fallow land ), the combination of species becomes more and more similar. From the west (Ireland) to eastern Central Europe, a sequence of characteristic species combinations can be identified with a common basic stock of species, which are often understood as their own associations. The association Mesobrometum, which occurs mainly in southern Germany, only covers part of it.

  • Helictotrichon pubescens

  • Briza media

  • Scabiosa columbaria (flower with six-spotted ram Zygaena filipendulae )

  • Onobrychis viciifolia

  • Ranunculus bulbosus

  • Viola hirta

  • Prunella grandiflora

  • Carlina vulgaris

  • Salvia pratensis

  • Primula veris

The bristle dry lawns are particularly rich in orchid species. Typical species Military Orchid Orchis militaris , three-toothed orchid Neotinea tridentata , Fire Orchid Neotinea ustulata , himantoglossum hircinum Himantoglossum hircinum , Fly Orchid Ophrys insectifera , Bee Orchid Ophrys apifera and numerous others.

Steppe lawn

Steppe grasslands ( Pálava , South Moravia)
Steppe lawn in Austria (NSG "Haulesbergen" near Mistelbach) with the dwarf iris Iris pumila

In northeastern and eastern Central Europe, the Trespen dry grasslands are being replaced by steppe grasslands. In Germany, steppe habitats can develop in regions with usually less than 500 to 600 mm of annual precipitation . They gradually merge into the real steppes of Eastern Europe and the subsequent Asia, in contrast to these, however, they are not naturally forest-free due to insufficient rainfall, but have lost their tree population through human use. Both are so related in their species composition that they are placed in the same order Festucetalia vallesiacae in the plant-sociological system (although there are also areas of other vegetation types widely within the steppes, for example on sandy or salt-influenced soils). This is named after the Valais fescue Festuca valesiaca , a species from the sheep fescue species . Also typical is the delicate Schillergrass Koeleria macrantha . More striking for the steppe lawns, however, are the feather grasses , especially real feather grass Stipa pennata and hairy awl grass Stipa capillata . However, these only predominate in initial or disturbed steppe lawns, with partially open ground, or in rocky steppes. Steppe lawns occur in Central Europe from the central German dry area in the Harz foreland, Rheinhessen, the area around Würzburg, the eastern Franconian Jura and the lower Danube valley to the east. Further west they only thrive in the inner-alpine dry valleys such as the Wallis or the Vinschgau , which also have a more continental climate. In Austria, steppe vegetation is concentrated in the Weinviertel in Lower Austria, the Vienna Basin and northern Burgenland, the largest preserved steppes are in the Steinfeld near Wiener Neustadt . The steppe region is seen as a Pannonian flora province .

After the drought of the location of the real steppe grass (a distinction Association valesiacae Festucion, all companies in Germany endangered (Red List 2) and the thistle-Zwenkenrasen (Cirsio pannonici-Brachypodion pinnati) on fresher and more profound locations, strong in Germany endangered (Red list 2). the character types include pulsatilla pratensis Pulsatilla pratensis subsp. nigricans , pheasant's eye Adonis vernalis , Stemless Astragalus Astragalus exscapus , Shaggy Spitzkiel Oxytropis pilosa) , sand cinquefoil Potentilla incana , equine Sesel Seseli hippomarathrum , ear spoon campion Silene otites .

Limestone grasslands of Northern Europe

The limestone grasslands of Ireland, England and Scandinavia as well as the Baltic States and north-east Germany (Mecklenburg-Western Pomerania and Brandenburg) differ from the south-central European in their species composition. Various names are used for the vegetation in this area. Most authors still classify the more widespread western ones as Trespen dry grass. Various names have been suggested for the more widely distributed ones to the east, some authors call them Helianthemo-Globularion, others prefer the name Filipendulo vulgaris-Helictotrichion pratensis, numerous other names are in use It is typical, in addition to the failure of numerous south-widespread species, that acid-bearing species are more common . The real meadow oat Helictotrichon pratense is far more common and constant than further south. Other typical species are Meadowsweet Filipendula vulgaris , Crack strawberry Fragaria viridis , Bastard lady's mantle Alchemilla glaucescens and Nordic bedstraw Galium boreale .

Mushrooms

Lime grasslands are, with rich fauna and flora, rather poor in characteristic mushroom species. Among the species that have their main distribution here include Kalkliebender felt Saftling Hygrocybe calciphila , Rough or Starkbehöfter Earthstar Geastrum berkeleyi and Black Red promontory Geoglossum atropurpureum . Other calcareous hands are Filziger Bovist Bovista tomentosa and Schwarzbehöfter Stielbovist Tulostoma melanocyclum .

fauna

Limestone grasslands are among the most biodiverse habitats in northwest Europe. Numerous animal species live here that are particularly dependent on drought and warmth, so-called xerothermophile species. Mostly these are species with a focus on occurrence in the northern Mediterranean or the mountainous areas of the Mediterranean region, so-called sub-Mediterranean species. Most of the species widespread here have a larger area and reach the northern limit of their distribution in the limestone grasslands. On the other hand, there are very few endemic species that are exclusively or mainly exclusively distributed here. In addition to species with a high need for warmth and specialists for habitats with open ground or areas with little vegetation cover, specialized herbivores of plant species that are widespread here, for example butterflies, and also species that colonize limestone grasslands as part of a habitat in larger vegetation mosaics contribute to the richness of species in lime-depleted grasslands , for example species that prefer low grass-like vegetation together with bushes.

Birds

Bird species with a distribution focus in limestone grasslands or mostly complexes of grasslands with hedges and shrubbery include species such as Ortolan Emberiza hortulana , barn warbler Sylvia nisoria , woodlark Lullula arborea , red- backed shrike Lanius collurio . Only rarely and at margins reach specialists steppe habitats that Central Europe is about curlew Burhinus oedicnemus and bustards as Great Bustard Otis tarda and little bustard Tetrax tetrax . In the kurzrasigen stocks hunt in Southern and Eastern Europe preferred raptors such as red-footed falcon Falco vespertinus , Lanner Falcon Falco biarmicus , honey buzzard Pernis apivorus , Short-toed Eagle Circaetus gallicus and Montagu's Harrier Circus pygargus .

Butterflies

Limestone grasslands are one of the European habitat types with the most butterfly species , with 274 species, around half of all European species occur here, including 37 endangered species. Among the species occurring here, for example, silver-green blue-blue polyommatus coridon , sky-blue blue-blue polyommatus bellargus , red cube-headed butterfly Spialia sertorius , Colias erate , cross- gentian blue-blue phengaris rebeli have their main distribution focus. For the protection of species, the habitat is also of particular importance for the mottled brown thick-headed butterfly Thymelicus acteon and the orange-red hay butterfly Colias myrmidone

  • Polyommatus coridon

  • Polyommatus bellargus

  • Spialia sertorius

  • Colias erate

  • Phengaris rebeli

  • Thymelicus acteon

  • Colias myrmidone

The red rams are another group that is typical of limestone grasslands. The most common species are mostly six-spot ram Zygaena filipendulae and thyme ram Zygaena purpuralis . The number of butterflies, especially butterflies, on lime-lime grasslands has been declining worryingly for decades. So far, this also applies to protected areas and to areas with biotope maintenance through nature conservation. In order to protect the species of butterflies on lime-lean grasslands, when cared for by mowing, either a late cut or leaving the stock on around 10 to 20 percent of the area is recommended.

Grasshoppers

Lean calcareous grasslands are one of the habitat types of particular importance for locusts in Central Europe. Their settlement depends, however, not only on the height of vegetation, their structure and cover, but also strongly on the region / natural space , so that there are already noticeable regional differences in areas such as the state of Baden-Württemberg. In addition to numerous more widespread species, the typical species endowment includes the red club insect Gomphocerippus rufus , the field cricket Gryllus campestris , the heather grasshopper Stenobothrus lineatus , the two-colored pecker Metrioptera bicolor , the western peregrine Platycleis albopunctata . In addition, there is a species group that prefers well-sunlit, low-vegetation ground areas that are preferably preserved in the area of ​​poor grassland. They include Blue-winged Grasshopper Oedipoda caerulescens , Rotflügelige Schnarr cricket Psophus stridulus , Schwarzfleckiger grasshopper Stenobothrus nigromaculatus , Rotleibiger grasshopper Omocestus hemorrhoidal , long horned grasshopper thorn Tetrix tenuicornis , two spot-thorn cricket Tetrix bipunctata . In other regions, in addition to some of the mentioned, other species occur preferentially in limestone grasslands, for example the wart- biter Decticus verrucivorus in Brandenburg, steppe grasshopper Chorthippus vagans in Thuringia. In England, the following are characteristic species: Gomphocerippus rufus , Stenobothrus lineatus , the bellied grasshopper Omocestus rufipes (in bushy limestone grasslands), Decticus verrucivorus . In contrast to the butterfly fauna, the grasshopper fauna of the limestone grasslands is often better preserved, as long as their habitats still exist, many species have decreased much less in their distribution. A decline can be seen here, especially in species of soil with little vegetation.

Ground beetle

In the family of ground beetles (Carabidae), which is often used for bioindication , about a third are species whose occurrence in Central Europe is in warm, dry biotopes. Here the proportion of species that overwinter as larvae and that of diurnal species is significantly higher than in the total fauna; This means that species with a light-colored or metallic surface that reflects light and heat are proportionally more common than black species. The mostly loamy soils of the limestone grasslands favor a different fauna than other xerothermal habitats such as the sandy soils of the dunes and sandy grasslands. This z. B. more species looking for hiding places in crevices than those with a burrowing way of life. The species Amara eurynota , Amara nitida , Bembidion pygmaeum , Cymindis angularis , Cymindis axillaris , Ophonus azureus , Ophonus cordatus , Ophonus puncticollis and Panagaeus bipustulatus are typical of limestone grasslands and other dry biotopes on limestone soils . Brachinus crepitans , Callistus lunatus , Licinus cassideus , Olisthopus rotundatus and Ophonus stictus prefer warmth, but slightly higher soil moisture and thus habitats with a meadow-like closed vegetation cover . A large number of these species are also considered typical of limestone grasslands in England.

natural reserve

Maintenance of a lean lime lawn in the Wulsenberg nature reserve near Marsberg, Westphalia

In the Flora-Fauna-Habitat Directive of the European Union, the habitat type 6210 Near-natural dry lime lawn and its bushing stages (Festuco-Brometalia) is defined as a biotope type worthy of protection . In addition, “stands of remarkable orchids” are a “priority” habitat type, for the conservation of which the European Union bears particular responsibility.

The habitat type is also the habitat of the priority species Pulsatilla slavika , Gentianella anglica and Maculinea arion .

Lean calcareous lawns are threatened by unsuitable management, such as over- or undergrazing , complete abandonment of use with succession via various bushes, ultimately to the beech forest, afforestation, penetration of undesirable " weed " species, but above all through increased agricultural use and fertilization the transformation into fat meadows. The entry of nitrogen compounds from air pollution, which also has a fertilizing effect, also has a disadvantageous effect. Some stocks are also threatened by other activities such as limestone quarries or excessive recreational use. Maintenance interventions are necessary to maintain the limestone grasslands as a unit of vegetation created by man. If the areas are only placed under nature protection but not maintained, they will disappear over the course of a few decades and will be replaced by forests and bushes. The maintenance should both prevent the advancement of woody plants and push back competitive high-growing herbaceous species and tall grasses, and it should also counteract the formation of a dense above-ground layer of litter with a growth-stifling effect and the enrichment of nutrients. Both mowing and grazing have advantages and disadvantages for maintaining the land. Grazing is possible with cattle, sheep and goats, while horses are generally considered to be rather disadvantageous for caring for them. Both short-term grazing with high livestock densities and year-round grazing are possible, in which case grazing densities of 2.5 sheep or 0.5 cattle per hectare should not be exceeded (guide value 0.25 livestock units per hectare and year). When mowing on the nutrient-poor locations, a single mowing is recommended in autumn, for Switzerland: more in midsummer (July). In general, care should be based on historical agricultural use, which has become unprofitable even today and is no longer practiced.

While the steppe lawns (or meadow steppes) of Europe were originally included under this habitat type, the additional habitat type 6240, Sub-Pannonian steppe dry lawns, was subsequently introduced for them after Austria, Finland and Sweden joined the EU. With the accession of the Balkan countries of Southeast Europe with more extensive steppe vegetation, this was subdivided and differentiated even more finely. Protected areas of the Natura 2000 network have also been designated for habitat type 6240 in Germany, primarily in the federal states of Saxony-Anhalt and Brandenburg. The designation of protected areas to protect these habitats, the Natura 2000 area, often casually referred to as the “FFH area”, is the responsibility of all member states.

See also

Individual evidence

  1. ↑ a b c d Heinz Ellenberg: Vegetation of Central Europe with the Alps in an ecological, dynamic and historical perspective. 5th edition, 1996. Ulmer-Verlag, Stuttgart. ISBN 3-8252-8104-3 therein Section D1, More or less dry grasslands of the colline to montane level, page 665 ff.
  2. ↑ Xerobrometum, in floraweb, published by the BfN Federal Agency for Nature Conservation , accessed on July 21, 2016
  3. ↑ Brometum in floraweb, published by the BfN Federal Agency for Nature Conservation , accessed on July 21, 2016
  4. ↑ Erich Oberdorfer: South German Plant Societies. Part II Sand and dry grasslands, heather and bristle grass societies, alpine poor grasslands, fringing societies, perennial and perennial fields. 2nd edition, 1978. Gustav Fischer Verlag, Jena, ISBN 3-437-30282-5 , therein class Festuco-Brometea, page 86 ff.
  5. ^ JH Willems (1982): Phytosociological and Geographical Survey of Mesobromion Communities in Western Europe. Vegetatio 48 (3): 227-240.
  6. ↑ Axel Ssymank: The steppe habitats in the Natura 2000 network of the EU 27 countries. In Thuringian Ministry of Agriculture, Forests, Environment and Nature Conservation (publisher) (2013): Proceedings international conference: “Steppe habitats in Europe - Endangerment, conservation measures and protection” from June 3rd to 6th, 2012 in Erfurt: 456 pages; ISBN 978-3-00-044248-3 . PDF
  7. ↑ Luise Schratt-Ehrendorfer: The flora of the steppes of Lower Austria: flora and vegetation, site diversity and endangerment. In: Heinz Wiesbauer (editor): The steppe is alive. Rock steppes and dry grasslands in Lower Austria. St. Pölten, 2008. ISBN 3-901542-28-0 online ( Memento of the original from July 14, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.steppe.at
  8. ↑ Festucion valesiacae in floraweb, published by the BfN Federal Agency for Nature Conservation , accessed on July 21, 2016
  9. ↑ Adonisröschen-Fiederzwenken-Rasen in floraweb, published by the BfN Federal Agency for Nature Conservation , accessed on July 21, 2016
  10. ↑ Jürgen Dengler et al. (2006): Working group on dry grasslands in the Nordic and Baltic region - outline of the project and first results for the class Festuco-Brometea. Annali di Botanica, nuova series 6: 1-28.
  11. ↑ a b Jürgen Dengler: Class Festoco-Brometea. In Christian Berg, Jürgen Dengler, Anja Abdank, Maike Isermann (2004): The plant communities of Mecklenburg-Western Pomerania and their endangerment. Weißdorn-Verlag, Jena, 2004.
  12. ↑ W. Winterhoff (1996): The mushroom flora of the poor grasslands - endangerment and protection. Ber. ANL I 20, 163-170. pdf
  13. ↑ European Commission, Directorate-General for the Environment (editor): LIFE and Europe's grasslands. Restoring a forgotten habitat. Luxembourg: Office for Official Publications of the European Communities, 2008. ISBN 978-92-79-10159-5 . doi: 10.2779 / 23028
  14. ↑ a b Barbara Calaciura & Oliviero Spinelli (2008): Management of Natura 2000 habitats. 6210 Semi-natural dry grasslands and scrubland facies on calcareous substrates (Festuco-Brometalia) (* important orchid sites). European Commission Technical Report 2008 12/24. ISBN 978-92-79-08326-6
  15. ↑ Chris van Swaay, Martin Warren, Gregoire Loıs (2006): Biotope use and trends of European butterflies. Journal of Insect Conservation 10: 189-209. doi: 10.1007 / s10841-006-6293-4
  16. ↑ CAM van Swaay (2002): The importance of calcareous grasslands for butterflies in Europe. Biological Conservation 104: 315-318.
  17. ↑ Wolfgang Wagner: Niche mechanisms in red rams (Lepidoptera: Zygaenidae) on limestone grasslands of the Swabian Alb (Baden-Württemberg). Dissertation, Ulm University, 2002.
  18. ↑ Miriam Wenzel, Thomas Schmitt, Matthias Weitzel, Alfred Seitz (2006): The severe decline of butterflies on western German calcareous grasslands during the last 30 years: A conservation problem. Biological Conservation 128 (4): 542-552. doi: 10.1016 / j.biocon.2005.10.022
  19. ↑ Katharina J. Filz, Jan O. Engler, Johannes Stoffels, Matthias Weitzel, Thomas Schmitt (2013): Missing the target? A critical view on butterfly conservation efforts on calcareous grasslands in south-western Germany. Biodiversity and Conservation 22: 2223-2241. doi: 10.1007 / s10531-012-0413-0
  20. ↑ Laura Bruppacher, Jérôme Pellet, Raphaël Arlettaz, Jean-Yves Humbert (2016): Simple modifications of mowing regime promote butterflies in extensively managed meadows: Evidence from field-scale experiments. Biological Conservation 196: 196-202. doi: 10.1016 / j.biocon.2016.02.018
  21. ↑ Peter Detzel: The locusts of Baden-Württemberg. Ulmer Verlag, Stuttgart, 1998. ISBN 3-8001-3507-8 . therein chapter 14.5.2 the grasshopper fauna of the limestone grasslands and juniper heaths, page 100 ff.
  22. ↑ a b Sebastian Schuch, Julian Bock, Christoph Leuschner, Matthias Schaefer, Karsten Wesche (2011): Minor changes in orthopteran assemblages of Central European protected dry grasslands during the last 40 years. Journal of Insect Conservation 15: 811-822. doi: 10.1007 / s10841-011-9379-6
  23. ↑ a b KNA Alexander: A review of the invertebrates associated with lowland calcareous grassland. English Nature Research Reports Number 512. English Nature (now: Natural England ), April 2003.
  24. ↑ Gerd Müller-Motzfeld (2004): Xerothermic ground beetles in Germany - distribution and endangerment. Applied Carabidology Supplement 3 (ground beetles in xerothermal biotopes): 27-44.
  25. ↑ Jacqueline Diacon, Matthias Bürgi, Thomas Dalang: Systematic review of management influences on dry meadows and pastures (SR-TWW), final report for the Federal Office for the Environment (FOEN). published by the Swiss Federal Research Institute WSL, Birmensdorf, 2011. PDF
  26. ^ Sub-Pannonian steppe dry grasslands. The habitat types and species (protected objects) of the Habitats and Birds Directive. BfN Federal Agency for Nature Conservation ( Memento of the original from July 22, 2016 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Retrieved July 22, 2016  @1@ 2Template: Webachiv / IABot / www.bfn.de