17G1

G. Forests

Oriental durmast(Quercus polycarpa) forests

Relationships with habitat classifications. EUNIS: G1.76A41 Stranja [Primula rosea]-[Quercus polycarpa] forests; PAL. CLASS.: 41.76A41 Stranja [Primula rosea]-[Quercus polycarpa] forests; HD 92/43: 91M0 Pannonian-Balkanic Turkey oak-sessile oak forests; Bondev (1991): 82 Oriental Durmast (Querceta policarpae) forests, 83 Mixed Oriental durmast (Quercus polycarpa) and Ordinary hornbeam (Carpinus betulus) forests, 84 Mixed Oriental durmast (Quercus polycarpa), Quercus frainetto and Cerris oak (Quercus cerris) forests, 85 Mixed Oriental durmast (Quercus polycarpa) and Quercus frainetto forests.

Conservation status. BDA, BC, HD.

Category. Endangered [EN – A1, 2 C1 D1 E2 F2 G2 H2 L3].

General characteristics. This habitat type encompasses the xeromesophilic oak forests in which the Oriental durmast (Quercus polycarpa) prevails. They are distributed in the mountains on the western coast of the Black Sea (Strandzha Mts. and Eeast Balkan Range). High precipitation level, high air and soil humidity, and relatively high summer temperature are typical. The communities of the Oriental durmast are relatively diverse. Its coenoses are either monodominant or mixed mainly with Quercus frainetto, Quercus cerris, Quercus hartwissiana, Carpinus betulus and Carpinus orientalis. There are certain specificities in the distribution and composition of the coenoses of the Oriental durmast depending on the microclimatic conditions. The northern slopes of the ravines, where the humidity is higher and persistent almost throughout the whole year, are occupied by monodominant coenoses or coenoses with Oriental beech and Common hornbeam. Quercus polycarpa makes mixed coenoses with Quercus frainetto, Q. cerris and more rarely with Carpinus betulus and C. orientalis on the mountain ridges, where the soils are drier and more shallow.

The monodominant and mixed forests of Oriental durmast and Oriental beech have diverse floristic composition and structure. Acer campestre, Malus sylvestris, Pyrus bulgarica (= Pyrus elaeagrifolia subsp. bulgarica), P. pyraster, Sorbus domestica, S. torminalis also occur apart from the tree species mentioned above. The shrub layer consists mainly of Crataegus monogyna, C. pentagyna, Mespilus germanica, and only in Strandzha Mts., only in certain localities, evergreen shrubs also occur such as Calluna vulgaris, Daphne pontica, Epimedium pubigerum, Rhododendron ponticum and more rarely Erica arborea as well as the deciduous species Genista carinalis, Vaccinium arctostaphylos etc. In East Strandzha Mts. the evergreen Hypericum calycinum gives specific yellow aspect to the coenoses. Sometimes, in drier and higher places in the mountains, this species dominates the ground layer on relatively large areas. When the trees are rarer the participation of Calluna vulgaris and Genista carinalis increases. The herbaceous layer consists mainly of Brachypodium sylvaticum, Dactylis glomerata, Melica uniflora, Poa nemoralis. Often some southern-Euxinian elements also participate such as Cyclamen coum, Dorycnium graecum, Polygala supina, Primula vulgarissubsp. sibthorpii, Salvia forskaohlei, Sesleria alba, Trachystemon orientalis, Verbascum lagurus subsp. ponticum etc.

Of the mixed coenoses of Quercus polycarpa, the most widely distributed are the woods of Q. polycarpa and Q. frainetto. Fraxinus ornus, Quercus cerris, Q. hartwissiana, Sorbus domestica, S. torminalis etc. also occur together with the dominants. The understory of these forests consists of Crataegus monogyna, Cornus mas, C. sanguinea, Daphne pontica, Mespilus germanica, Pyracantha coccinea etc. Brachypodium sylvaticum, B. pinnatum, Dactylis glomerata, Euphorbia amygdaloides, Lathyrus niger, Melica uniflora, Poa nemoralis, Primula vulgarissubsp. sibthorpii, Stellaria holostea, Viola spp. etc. participate in the herbaceous layer.

Another type of mixed coenoses of the Oriental durmast are the woods in which Q. frainetto and Q. cerris are also ediphicators. Their ecotopes occupy mainly the tops of western, eastern and partly southern slopes. Crataegus monogyna, Cornus mas, Euonymus europaeus, Mespilus germanica etc. are typical for the understory. The herbaceous layer consists of Dactylis glomerata, Dorycnium graecum, Euphorbia amygdaloides, Festuca heterophylla, Mycelis muralis, Salvia forskaohlei, Stellaria holosteaetc. The communities of the Oriental durmast belong to the autochthonous South-Euxinian vegetation in Bulgaria.

Special attention should also be given to the forests in which Quercus hartwissiana participates. It is one of the most typical South-Euxinian Tertiary relics. The ecological plasticity of the species is relatively high and it occurs in two main habitat types on the northern slopes of Strandzha Mts. The first ecotope type in which Quercus hartwissiana occurs are the humid, but rarely flooded, riverside terraces and the lower slopes beside Veleka, Rezovska, Trionski Dol, Mladezhka, Kerina Reka, Lopushnitsa and other small rivers. In these places Quercus hartwissiana grows together with Carpinus betulus, Fagus orientalis, Fraxinus oxycarpa, Quercus cerris, Q. frainetto, Q. polycarpa, and each of the tree species can dominate depending on the local conditions. The presence of winding plants such as Clematis vitalba, C. viticella, Humulus lupulus, Smilax excelsa, and Tamus communis is also typical. Hence these forests are very similar to the longoz forests in outlook. A coenoses dominated by Quercus hartwissiana have been recorded in only one locality in the valley of Rezovska river. The forest consists of trees 20–28 m high. Single trees of Quercus cerris, Acer pseudoplatanus, Fagus orientalis, and Carpinus betulus occur together with Quercus hartwissiana. Hedera helix is widely distributed as well. The shrubs Crataegus monogyna, Cornus mas, Ulmus minor, Acer campestre, Corylus avelana and herbs Ruscus aculeatus, Mercurialis perennis, Viola suavis, Alliaria petiolata also occur. The second ecotope type is completely different – Quercus hartwissiana occurs on dry, calcareous places on humus-carbonate soils and participates in the composition of xerothermic tree coenoses together with Carpinus orientalis, Fraxinus ornus, Quercus cerris, Q. frainetto and Q. pubescens. These coenoses occur near Malko Tarnovo town and Brashlyan, Zvezdets and Evronozovo villages. The communities with Quercus hartwissiana are unique, with a diverse composition and complex structure.

Characteristic taxa.

Distribution in Bulgaria. The northern slopes of Strandzha Mts. and East Balkan Range (Kamchiyska and Eminska Mts; up to 700 m alt.

Conservation importance. These forests have been subjected to a very strong anthropogenic pressure – logging, eradication in the past, grazing, etc. Some rare, endangered and protected species occur in them like Calluna vulgaris, Erica arborea, Vaccinium arctostaphylos, Hypericum calycinum, Quercus hartwissiana, Verbascum lagurus subsp. ponticum, Pyracantha coccinea, Epimedium pubigerum, Rhododendron ponticum etc. Fungi species of conservation value are Agaricus altipes, Amanita caesarea, Boletus armeniacus, Hericium erinaceum, Melanogaster variegatus.

Threats. Wood felling and unregulated felling, construction of truck roads and related erosion, building infrastructure facilities, grazing, planting of non-typical species, climate aridisation, etc.

Conservation measures taken. The habitat is included in Annex № 1 of BDA. Parts of these forests are within protected areas: Strandzha Nature Park, Silkosiya, Uzunbudzhak, Vitanovo, Sredoka, Tisovitsa Strict Nature Reserves, Veleka, Paroria, Ortoto Protected Sites, etc. Most of the representative localities are within sites of the European Ecological Network NATURA 2000.

Conservation measures needed. Monitoring, restoration and sustainable economic exploitation of the forests.

References. Gussev et al. 2004; Jordanoff 1939; Patronov 2004; Stefanov 1924.

Authors: Chavdar Gussev, Rossen Tzonev


Oriental durmast (Quercus polycarpa) forests (distribution map)