Title
Southwest Caucasian krummholz and open woodlands (Betula litwinowii, Fagus sylvatica subsp. orientalis, Acer trautvetteri) with Betula megrelica, Quercus pontica, scrub (Rhododendron caucasicum) with Rhamnus imeretina (on carbonate rocks with Corylus colchica), tall-herb communities (Heracleum ponticum) with Delphinium pyramidatum (on carbonate rocks with Heracleum aconitifolium, Ligusticum arafoe) and grasslands (Calamagrostis arundinacea, Stachys macrantha, on carbonate rocks with Geum speciosum, Carex pontica)
Geographical distribution
Country/territory
Georgia (some regions in the Autonomy-Republic Abkhazskaya); Russia: southern flanks of the western Greater Caucasus (north Colchis, Krasnodar region)
area frequency
4 polygons.
Scientific names of main plant communities and their most common synonyms (with author citation)
Formation groups of subalpine krummholz forests, subalpine open woodlands, altimontane prostrate shrubs, tall herb communities and subalpine grasslands (Doluchanov et al. 1942) = Betulo-Adenostyletea Braun-Blanquet & R. Tüxen 1943; Calluno-Ulicetea Braun-Blanquet et R. Tüxen ex Westhoff et al. 1946; Caricetea curvulae Braun-Blanquet 1948; Molinio-Arrhenatheretea R. Tüxen 1937.
Structural feature of the main community(ies) (layers, life-forms, etc.)
See C41, in addition: usually two-layered Quercus pontica forests on southern slopes and up to altitudes of 2150 m, creeping, a height of approx. 4 m, a stem length of up to 10 m, and a density of 0.3-0.4; Corylus colchica communities: one-layered thickets on lime-rich soils of hollow slopes with a height of 1-1.5 m; low, one- to two-layered Rhamnus imeretina shrub forests with a height of 3-3.5 m.
Dominant and most frequent species in different layers
Tree layer
beech forests: Fagus sylvatica subsp. orientalis; oak forests: Quercus pontica; birch-krummholz forests: Betula litwinowii, Sorbus aucuparia, Acer trautvetteri, Populus tremula, Salix caprea; maple forests: Acer trautvetteri
Shrub layer
birch-krummholz forests: Rhododendron caucasicum or Lonicera caucasica, Ribes biebersteinii, Salix kazbekensis; Rhododendron communities: Rhododendron caucasicum; beech forests: Vaccinium arctostaphylos, Prunus laurocerasus, Rhododendron caucasicum, Ilex colchica, Daphne mezereum; oak forests: Prunus laurocerasus, Rhododendron ponticum, Rhododendron caucasicum
Herb layer
beech forests: Vaccinium myrtillus, Calamagrostis arundinacea, Festuca drymeja, Galium odoratum, Dryopteris oreades, Athyrium distentifolium; oak forests: Oreopteris limbosperma, Adenostyles platyphylloides, Adenostyles macrophylla; tall herb communities: Heracleum ponticum, Heracleum mantegazzianum, Telekia speciosa, Senecio othonnae, Delphinium pyramidatum, Inula magnifica, Ligusticum physospermifolium; grasslands: Calamagrostis arundinacea, Stachys macrantha, Geranium platypetalum, Geranium gymnocaulon, Poa iberica, Trollius ranunculinus, Geum speciosum and Carex pontica on calcareous rock
Moss layer (incl. lichens)
No details
Diagnostically important species
Sorbus aucuparia, Sorbus subfusca, Salix kazbekensis, Heracleum spp., Senecio othonnae, Ligusticum physospermifolium, Geranium gymnocaulon, Poa iberica, Athyrium distentifolium, Dryopteris oreades, Oreopteris limbosperma etc.
Ecological variants
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Geographical variants (geogr. differential species)
Quercus pontica, Betula megrelica, Vaccinium arctostaphylos, Rhododendron ponticum, Prunus laurocerasus, Ilex colchica, Rhamnus imeretina, Corylus colchica, Sorbus colchica, Delphinium pyramidatum, Heracleum aconitifolium, Ligusticum arafoe, Geum speciosum, Carex pontica.
Natural accompanying vegetation (most important units in complex with the name giving mapping unit, scientific names)
Fir forests (Abies nordmanniana), beech-fir forests, spruce-fir forests with Picea orientalis, pine-spruce forests, pine forests and forest landscapes with Pinus kochiana, Juniperus communis subsp. hemisphaerica communities, Vaccinium spp. communities, Corylus avellana communities, rock and rubble vegetation.
Adjoining climax and permanent vegetation (with numbers of mapping units)
alpine grasslands (B56), fir and mixed fir forests (D32, D33), pine forests (D64), Oriental beech forests (F163).
Land use, substitute communities
forestry (substitute communities, plantations of economic tree-species, scrub)
No plantations.
grassland (meadows, pastures, herb-rich communities)
Hay meadows and pastures, collection of herbs for medicinal purposes (perennial rich communities).
arable land (characteristic weed communities)
Cultivation of potatoes, barley.
settlements (typical ruderal vegetation)
Communities with Veratrum lobelianum, Cirsium spp., Rumex pseudoalpinus, Polygonum aviculare, Capsella bursa-pastoris, and partly Tephroseris cladobotrys, Anthriscus nemorosa, Plantago spp.
Site conditions of the mapping unit
Landscape type, geomorphology
High-mountain regions with relief strongly carved up by steep slopes, shaped by erosion and denudation, sometimes with a karst relief and with glacial forms (moraines, boulders etc.).
Altitudinal belt and/or altitudinal range
subalpine; 1800(1700)-2500(2650) m
Geology (bedrock)
slate, sandstone, limestone and chalky clay (Tertiary, Cretaceous, Jurassic)
soil type, also the depth of fine textured earth (soil), stone content; (international nomenclature)
mountain-meadow soils (mull-gley of the highlands), forest-meadow soils of the highlands (transitions between mull-gley and brown soils), brown forest soils (brown soils, burozem), humus carbonate soil, partly lithosole; (humic and dystric cambisols; umbric, lithic and rendzic leptosols)
soil texture
loamy, clayey
soil moisture, water balance
(moist) fresh to moderately dry (mostly moderately dry or fresh at southern and eastern slopes, at remaining slopes fresh, below krummholz forests moist)
soil reaction
acidic to alkaline
soil fertility
mesotrophic (high content of humus (10 % or more), high to moderately high content of nitrogen, moderately high content of potassium, low content of phosphorus)
Climate incl. local climate
climate type (following Walter & Lieth)
X
average annual temperature
3-4 °C
average annual precipitation
>2000 mm
average temperature of the warmest month
13-14 °C
average temperature of the coldest month
-5 to -4 °C
local climate or other climatic peculiarities
wet highland (and sea) climate with long, cold winters (4-5 months) and warm, short summers (2-2,5 months). In gorges there is a different air humidity to be found; it generally decreases from the west to the east (the average annual precipitation in the eastern part of the formation is about 1200-1400 mm). In 100 meters of altitude air temperature decreases about 0,65 °C on average (varying on the month and the exposition of the slope).
Importance for nature protection
Present state and development trend of natural vegetation (degree of endangerment)
The areas with subalpine forests have been greatly reduced and the tree line now lies about 200 m lower (sometimes 300-400 m). A natural regeneration of the subalpine forest is not possible since a grassland soil horizon has formed under the secondary grass communities.
endangered communities, species worthy of protection in natural vegetation
All subalpine forest types, tall herb vegetation.
causes of endangerment
Intense grazing, hay and timber harvesting by the locally resident population for private use, tourism.
required measures for protection and restitution
Protection of the still remaining subalpine forests in nature reserves, regulation of grazing, restoration of the krummholz and open forests (through replantation).
Localities of representative stands (loci typici) with state of protection
of the natural vegetation
Georgia: Ritsa reserve along the Upper Bzib (gorge of the Jupshara); Gumista reserve in the catchment area of the Gumista (eastern Gumista gorge).
of characteristic substitute communities worthy of protection
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Most important references (author, year)
Doluchanov 1956; Kolakovskij 1961; Sochadze 1982
Compiled by
N. Zazanašvili
