Title
Dry lichen heaths (Aspicilia calcarea, Cetraria nivalis, Collema spp.) and rocky dry grasslands (Festuca ovina, Helictotrichon pratense) with lichen and mosses on alvar limestone on the Öland and Gothland islands with Juniperus communis, Potentilla fruticosa, Helianthemum oelandicum, Globularia vulgaris, Artemisia laciniata, Thamnolia vermicularis alternating with Corylus-Crataegus-scrub and ash-oak forests (Quercus robur, Fraxinus excelsior)
Geographical distribution
Country/territory
Sweden: predominately on Öland and Gothland (further small areas in south Sweden)
area frequency
2 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
a) Lecanoretum calcareae, Collematetum tunaeformis; Sedetum tortellosum; b) Festucetum alvarense tortellosum/cetrariosum/racomitriosum; Avenetum alvarense (Albertson 1950); c) Berberidion Braun-Blanquet 1950, Fagetalia sylvaticae Pawlowski 1928.
Structural feature of the main community(ies) (layers, life-forms, etc.)
Landscape with horizontally sedimented limestones and mainly very shallow to rocky habitats. The parent rock (limestone) often protrudes superficially and is then only settled by lichens and mosses (a). Large areas are covered only by a thin soil layer and are therefore free of forest in nature. On rocky sites, Sedum album is widespread; on deep soils, low dry grasslands (b) with Festuca ovina, Helictotrichon pratense amongst other xerophytic species; in shallow basins moist meadows, alvar swamps and calcareous fens occur locally. Broad-leaved trees, scrub and fragmentary broad-leaved forests grow in fine earth rich fissures and depressions (c).
Dominant and most frequent species in different layers
Tree layer
c) isolated Quercus robur, Fraxinus excelsior, Betula pendula, Populus tremula, Sorbus intermedia, Pyrus communis
Shrub layer
c) scrubs: Corylus avellana, Crataegus spp., Juniperus communis, Prunus spinosa, Hippocrepis emerus, Cotoneaster niger, Cotoneaster integerrimus, Rosa canina, Rosa dumalis, Rosa rubiginosa, Rosa villosa, Rhamnus cathartica, Cornus sanguinea, Potentilla fruticosa
Herb layer
b) dry grassland: Festuca ovina, Helictotrichon pratense, Sesleria caerulea, Melica ciliata, Brachypodium pinnatum, Agrostis gigantea, Phleum phleoides, Briza media, Carex flacca, Acinos arvensis, Artemisia laciniata, Artemisia rupestris, Cerastium pumilum, Erophila verna, Globularia vulgaris, Gypsophila fastigiata, Helianthemum oelandicum, Hornungia petraea, Orchis mascula, Orchis morio, Orchis ustulata, Oxytropis campestris, Potentilla incana, Filipendula vulgaris, Anthyllis vulneraria, Carlina vulgaris, Potentilla tabernaemontani, Pulsatilla pratensis, Aster linosyris, Polygala comosa, Prunella grandiflora, Ranunculus illyricus, Scabiosa columbaria, Saxifraga tridactylites, Sedum acre, Sedum album, Sedum rupestre, Thymus serpyllum; below woody plants: Hepatica nobilis, Sanicula europaea, Geranium lucidum, Viola hirta, Geranium sanguineum, Vincetoxicum hirundinaria, Polygonatum odoratum, Convallaria majalis, Mercurialis perennis, Dryopteris filix-mas, Primula veris
Moss layer (incl. lichens)
a) lichen: Aspicilia calcarea, Cetraria nivalis, Cetraria islandica, Collema spp., Dermatocarpon spp., Fulgensia spp., Lecidea decipiens, Thamnolia vermicularis;
b) mosses: Homalothecium lutescens, Schistidium apocarpum, Tortella inclinata, Tortella tortuosa, Ditrichum flexicaule, Rhytidium rugosum, Thuidium abietinum
Diagnostically important species
Aspicilia calcarea, Cetraria nivalis, Collema spp., Thamnolia vermicularis; Festuca ovina, Helictotrichon pratense, Potentilla fruticosa, Helianthemum oelandicum, Globularia vulgaris, Artemisia laciniata; Juniperus communis, Hippocrepis emerus
Ecological variants
Very multiform, depending on lime content, depth and moisture of the soil.
Geographical variants (geogr. differential species)
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Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
Bog hollow vegetation: Litorella uniflora community, Agrostis stolonifera-Alopecurus geniculatus-Scorpidium turgescens community; marsh ponds with sedge reeds (Carex elata, Carex lasiocarpa, Chara contraria, Chara aspera, Cladium mariscum, Menyanthes trifoliata).
Adjoining climax and permanent vegetation (with numbers of mapping units)
acidic pedunculate oak forests (F10), salt vegetation (P22).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
Locally coniferous forestry, juniper scrub, thermophilous fringes (Geranion sanguinei, Trifolion medii).
grassland (meadows, pastures, herb-rich communities)
Short-grass meadows with Sesleria caerulea, Briza media, Cynosurus cristatus: extensive grazing by sheep, cattle and horses; moist meadows (Molinietum alvarense) with Sesleria caerulea, Molinia caerulea, Carex hostiana.
arable land (characteristic weed communities)
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settlements (typical ruderal vegetation)
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Site conditions of the mapping unit
Landscape type, geomorphology
flat, shallow calcareous rock and karst landscape, locally overlaid with shallow morainal ramparts and glaciofluvial sediments
Altitudinal belt and/or altitudinal range
lowland
Geology (bedrock)
limestone (Ordovician, Silurian), locally moraines, glacifluvial sediments (Pleistocene)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
limestone-raw soils (lime-syrosem), shallow humus carbonate soils, locally base-rich brown soils, frost-polygones; (lithic and rendzic leptosols; eutric cambisols)
soil texture
rocky, stony, grouany, humic loam
soil moisture, water balance
moderately dry to very dry, periodically dry , periodically moist (partly fast percolation of precipitation water, partly large-scaled temporary floods, locally temporary to permanent swamps and ponds in land depressions)
soil reaction
alkaline to weakly acidic
soil fertility
lime-oligotrophic, mesotrophic
Climate incl. local climate
climate type (following Walter & Lieth)
VI2, VI(VII)
average annual temperature
6-8 °C
average annual precipitation
400-500 mm
average temperature of the warmest month
16-18 °C
average temperature of the coldest month
-2 to 0 °C
local climate or other climatic peculiarities
distinct dry seasons in summer, extreme changes in temperature close to the soil surface; strong wind-exposition.
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
The alvar vegetation is unique to Scandinavia and is closely related both to the alpine vegetation in northern Scandinavia and to the dry grassland and steppe vegetation in southern and south-east Europe. The community complex as a whole is very important for nature conservation.
endangered communities, species worthy of protection in natural vegetation
Adonis vernalis, Anacamptis pyramidalis, Allium strictum, Anemone sylvestris, Anthericum liliago (only Öland), Anthericum ramosum, Apera interrupta, Artemisia laciniata, Artemisia rupestris, Aster linosyris, Dactylorhiza sambucina, Dracocephalum ruyschiana, Fumana procumbens, Galium oelandicum, Globularia vulgaris, Gypsophila fastigiata, Helianthemum oelandicum subsp. incanum, Helianthemum oelandicum subsp. italicum, Hippocrepis emerus, Orchis morio, Orchis ustulata, Orobanche purpurea, Oxytropis campestris, Potentilla incana, Potentilla fruticosa, Plantago tenuiflora, Prunella grandiflora, Ranunculus illyricus, Sesleria caerulea, Silene suecica, Veronica spicata, Viola elatior, Viola pumila, Viola alba.
causes of endangerment
Irregular, particularly excessive grazing; influences from tourism and quarrying.
required measures for protection and restitution
Protection of the community complex as a whole is necessary. In order to preserve the anthropogenic short-grass meadows, scrub removal and continuation of traditional grazing practices are necessary in part.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Sweden: Öland: areas east of Resmo, Mörbylanga; southernmost Gothland: areas east of Sandre.
of characteristic substitute communities worthy of protection
Öland.
Most important references (author, year)
Albertson 1946; Albertson 1950; Königsson 1968; Rosén 1982; Sjögren (Ed.) 1988; Sterner 1938
Compiled by
L. Påhlsson, completed by U. Bohn referring to Albertson (1950), Rosén 1982, Sjögren (1988)
