13F2
Green alder (Alnus viridis) mountain brush
Relationships with habitat classifications. EUNIS: F2.311 Green alder brush; PAL. CLASS.: 31.6114 Balkan Range Green alderbrush, 31.6115 Rhodopide Green alder brush; Bondev (1991): 3 Scrub community (Pineta mugi) partly mixed with potential shrubs (Alneta viridis, Saliceta waldsteinianae etc.) and secondary shrub (Junipereta sibiricae etc.), dwarf shrub (Vaccinieta vitis-idaeae etc.) and grass (Nardeta strictae, Festuceta validae etc.) community.
Conservation status. None.
Category. Endangered [EN – B1 C2 D2 E2 G2 H2 1].
General characteristics. The Green alder (Alnus viridis) is a deciduous shrub, 2,5 m high, densely branched from its base. Its distribution is relatively limited not only in Bulgaria and on the Balkans, but also in the mountains of Europe. The habitats are mostly in strips of different widths along the streams that run on steep or moderate rocky and stony slopes (from 10–15° up to 45–70°) and along rivers between (1500) 1900 and 2200 m alt. In winter the snow is high and protects the plants from temperature abnormalities. These places are protected to a certain extent against the cold northern and northwestern winds. At the same time the soil on the slopes of the mountains where the coenoses of the Green alder develop are more humid than the adjacent mountain areas. The air humidity is also high. The vegetation develops in the conditions of moderate continental climate modified into mountain climate in the high parts of Rila Mts. This vegetation type is more limited in Vitosha Mts and the Balkan Range. The phytocoenoses of the Green alder are more widely distributed on the western slopes of the Balkan Range that are beyond the Serbian border. The soils are acidic, very stony and rich in nutritional substances. Frequent changes in the thicknes of soil profile are observed throughout the habitat area. The habitats of Alnus viridis are a complicated complex of ecologically different micro-areas, hence the structure of the coenoses varies. Three parts of the ecotope can be distinguished with specific groups of species. In the area that is permanently covered by water (inside the river and on its periphery) and consists of stones, roots and branches among which detritus accumulates the following species are most frequent: Adenostyles alliariae, Angelica pancicii, Chrysosplenium alternifolium, Cicerbita alpina, Cirsium appendiculatum, Crepis paludosa, Doronicum columnae, Saxifraga rotundifolia, S. stellaris, Stellaria nemorum, Telekia speciosa,and many mosses: Fontinalis antipyretica, Marchantia polymorpha complex, Philonotis fontana, Plagiothecium nemorale, Scapania undulata, S. subalpina, etc. In the places next to the water flow and elevated above the water level but frequently flooded in the periods of high waters and sprinkled by the water the soil is permanently wet. Thefollowing species can be found there: Athyrium filix-femina, Caltha palustris, Cardamine amara, C. pratensis, Crepis paludosa, Dicranum scoparium, Geum coccineum, Heracleum verticillatum, Hypnum cupressiforme, Ligusticum mutellina, Lilium jankae, Oxalis acetosella, Polytrichum commune, Schistidium apocarpum, Veratrum album subsp. lobelianum. The ground layer of the vegetation in the driest and most stony places that are 1–2 m away from the water includes Aegopodium podagraria, Crepis paludosa, Cynoglossum creticum, Deschampsia flexuosa, Gentiana asclepiadea, Geum montanum, Hypericum maculatum, Juniperus sibirica, Lonicera xylosteum, Luzula sylvatica, Picea abies, Poa nemoralis, Rumex acetosa, Salix silesiaca, Thalictrum aquilegifolium, Vaccinium myrtillus and other species as well as many of the above-listed ones. Although the species composition of the phytocoenoses of the Green alder differs considerably there is one distinct group of species that unites them in one habitat type. At the timberline, along the streams in Vitosha Mts, especially in Bistrishko Braniste Strict Nature Reserve (1780 m alt.), dense brushes of Green alder are accompanied by Rubus idaeus, Salix caprea and many forest species like Ajuga genevensis, Athyrium filix-femina, Dryopteris filix-mas, Gentiana asclepiadea, Luzula sylvatica, Mycelis muralis, Oxalis acetosella, Poa nemoralis, Polystichum lonchitis. Heliophilic high-mountain species like Aegopodium podagraria, Alchemilla glaucescens, Angelica pancicii, Caltha palustris, Campanula patula subsp. abietina, Chaerophyllum aureum var. balcanicum, Cirsium appendiculatum, Deschampsia caespitosa, Geranium sylvaticum, Geum coccineum, Heracleum verticillatum, Homogyne alpina, Hypericum tetrapterum, Juncus thomasii, Myosotis scorpioides, Phleum alpinum, Rumex arifolius, Scrophularia scopolii, Senecio nemorensis, Soldanella rhodopaea, Vaccinium myrtillus, Valeriana tripteris, Veratrum album subsp. lobelianum, etc. also occur. In the West Balkan Range in Bulgaria the composition, structure and characteristics of the phytocoenoses are similar to those in Vitosha Mts. There are phytocoenoses of the Green alder with Calamagrostis arundinacea described from Bulgaria. Their distribution is relatively limited. The phytocoenoses from the Bulgarian mountains belong to the association Salici-Alnetum viridis that was described from the Serbian part of the Balkan Range and occurs also in southeastern parts of the Carpathians. The floristic composition and the structure of the phytocoenoses from the Serbian part of the Balkan Range are similar with these in Rila Mts. However, there are some specific differences. For instance Salix silesiaca is more limited in the phytocoenoses in Rila Mts. and its abundance is lower. In the composition of the phytocoenoses under consideration participate a large number of species from the alliance Cirsion appendiculati and order Adenostyletalia alliariae that are endemic to the Balkans. This is an argument supporting the affiliation of the association under consideration to the already mentioned syntaxa from the European class of the tall-herb vegetation Betulo-Adenostyletea.
Characteristic taxa.
- Vascular plants: Adenostyles alliariae, Alnus viridis, Athyrium filix-femina, Caltha palustris, Cardamine amara, C. pratensis, Chrysosplenium alternifolium, Cicerbita alpina, Crepis paludosa, Cynoglossum creticum, Doronicum columnae, Gentiana asclepiadea, Geum coccineum, G. montanum, Heracleum verticillatum, Hypericum maculatum, Ligusticum mutellina, Lilium jankae, Lonicera xylosteum, Luzula sylvatica, Oxalis acetosella, Picea abies, Poa nemoralis, Rumex acetosa, Salix silesiaca, Saxifraga rotundifolia, S. stellaris, Stellaria nemorum, Telekia speciosa, Thalictrum aquilegifolium, Veratrum album subsp. lobelianum, etc.; mosses – Dicranum scoparium, Fontinalis antipyretica, Hypnum cupressiforme, Marchantia polymorpha complex, Philonotis fontana, Plagiothecium nemorale, Polytrichum commune, Scapania subalpina, S. undulata, Schistidium apocarpum.
- Fungi: Macromycetes – Cystoderma amianthinum, Galerina hypnorum, Hygrocybe cantharellus, Hymenoscyphus calyculus, Inonotus hispidus, Peziza ostracoderma, Rickenella fibula;Micromycetes – Gnomonia alni-viridis, Microsphaera penicillata (on Alnus viridis).
Distribution in Bulgaria. Rila Mts., northern slopes of Vitosha Mts., West and Central Balkan Range; (1500) 1900 up to 2300 m alt.
Conservation importance. These phytocoenoses have a relatively limited distribution in the Balkans. The rare species Lilium jankae, and Aquilegia aurea occur.
Threats. Logging and burning of the plant communities.
Conservation measures taken. Phytocoenoses of the Green alder are within the borders of Rila National Park and Vitosha Nature Park. Some of the most representative localities are in sites of the European Ecological Network NATURA 2000 in Bulgaria.
Conservation measures needed. Strict implementation of the legislation related to national and nature parks; monitoring of the Green alder phytocoenoses.
References. Čolić et al. 1963, Ganchev 1963; Roussakova 2000.
Author: Veska Roussakova
