Title
South Transcaucasian thorn-cushion vegetation (Astragalus aureus, Astragalus microcephalus, Astragalus lagopoides, Astragalus uraniolimneus, Acantholimon armenum, Onobrychis cornuta) with Astragalus hajastanus, Astragalus vedicus, Astragalus karabaghensis and tomillares with Stachys inflata, Salvia hydrangea, Thymus kotschyanus
Geographical distribution
Country/territory
Armenia: Ararat, border to Nakhichevan; Azerbaijan: Nakhichevan, south-western end of the Zangezur mountain ridge, central Karabach
area frequency
7 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Astragaleta aurei, Astragaleta microcephali, Astragaleta uraniolimnei.
Structural feature of the main community(ies) (layers, life-forms, etc.)
Thorn-cushion communities with dominant dwarf shrubs: Astragalus aureus, Astragalus microcephalus, Astragalus lagopoides, Astragalus uraniolimneus, Onobrychis cornuta; Steppe and mountain steppe species are frequently added. Geophytes and annuals are also typical. Tomillares with dwarf semishrubs. Onobrychis communities with dominant Onobrychis cornuta, as codominants Acantholimon species as well as Acanthophyllum mucronatum, Gypsophila aretioides, and amongst the typical components Astragalus elbrusensis, Astragalus cancellatus, Daphne kurdica. The flora of this mapping unit is diverse and species-rich (up to 250 vascular plant species). Many endemics and species with a north-Iranian and north-west Anatolian distribution are typical.
Dominant and most frequent species in different layers
Shrub layer
dwarf shrubs and thorn-cushion: Juniperus communis subsp. hemisphaerica, Prunus incana, Daphne kurdica, Astragalus aureus, Astragalus microcephalus, Astragalus lagopoides, Astragalus uraniolimneus, Onobrychis cornuta; codominants: Acantholimon armenum, Atraphaxis spinosa, Astragalus vedicus, Astragalus karabaghensis, Astragalus sangesuricus, Atraphaxis spinosa, Acantholimon armenum, Acantholimon araxanum, Acantholimon glumaceum, Scutellaria- and Stachys-species
Herb layer
Astragalus hajastanus, Stachys inflata, Salvia hydrangea, Thymus kotschyanus, Astragalus strictifolius, Astragalus oleifolius, Aethionema arabicum, Helianthemum lasiocarpum, Bromus tectorum, Poa bulbosa, Ajuga chia; geophytes: Hyacinthella atropatana, Allium akaka, Iris caucasica, Muscari-, Bellevalia-, Tulipa-species
Moss layer (incl. lichens)
No details
Diagnostically important species
Astragalus aureus, Astragalus microcephalus, Astragalus lagopoides, Astragalus uraniolimneus, Astragalus hajastanus, Astragalus vedicus, Astragalus karabaghensis, Astragalus strictifolius, Astragalus sangesuricus, Astragalus oleifolius, Onobrychis cornuta; Stachys inflata, Salvia hydrangea, Thymus kotschyanus, Acantholimon armenum, Acantholimon araxanum, Acantholimon glumaceum
Ecological variants
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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)
Artemisia communities, mountain steppes.
Adjoining climax and permanent vegetation (with numbers of mapping units)
alpine grasslands (B59), krummholz and open woodlands (C46, C47), Caucasian oak forests (F170, F172), juniper open woodlands (K33), mountain-steppes (M11), deserts (O7), salt vegetation (P36).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
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grassland (meadows, pastures, herb-rich communities)
Pastures.
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
steep mountain slopes
Altitudinal belt and/or altitudinal range
altimontane to alpine; 1100 to 2400 (3000) m. altitudinal distribution: 1100-1500 m (Astragalus microcephalus), as fas as 2000-3000 m (Astragalus aureus, Astragalus lagopoides, Astragalus uraniolimneus, Onobrychis cornuta)
Geology (bedrock)
sandstone and conglomerates, clay-slate (Tertiary; Mesozoic; Palaeozoic)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
stone-rich, partly weakly developed mountain soils; (rendzic leptosols; cambisols)
soil texture
loamy-stony; clay with rock fragments
soil moisture, water balance
dry
soil reaction
moderately to weakly acidic
soil fertility
oligo-mesotrophic
Climate incl. local climate
climate type (following Walter & Lieth)
VII(IV), X
average annual temperature
9-11 °C
average annual precipitation
300-400 mm
average temperature of the warmest month
July 20-25 °C
average temperature of the coldest month
January -6 to -3 °C
local climate or other climatic peculiarities
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Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
No details
endangered communities, species worthy of protection in natural vegetation
All nearly-natural preserved stands as well as endemic species are worthy of protection (Astragalus-species like Astragalus uraniolimneus, Astragalus lagopoides, Astragalus strictifolius, Astragalus vedicus, Astragalus karabaghensis, Astragalus sangesuricus, Astragalus arguricus, further Acantholimon armenum, Acantholimon araxanum, Nepeta trautvetteri, Allochrusa versicolor, Acanthophyllum mucronatum, Crambe armena, Salvia-species and many others).
causes of endangerment
Intensive grazing.
required measures for protection and restitution
Controlled grazing.
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Armenia, Azerbaijan: south Transcaucasia: at slopes of isolated mountains (Erach, Urts), at the ends of the mountain ridges Gegam (nature reserve Khosrov), Daralagez, Zangezur; central Karabach.
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Balojan & Gasanov 1990; Gabrieljan et al. 1988; Gabrieljan & Fajvuš 1990; Gabrieljan, Gejlikman & Unanjan 1990; Grossgejm 1940; Grossgejm 1948; Isaev 1940; Jarošenko 1956; Karjagin 1938; Prilipko 1970a; Prilipko 1980a; Tachtadžjan 1941a; Tachtadžjan 1941b; Tachtadžjan 1972
Compiled by
M. Ivanišvili
