35G3
Scots pine (Pinus sylvestris) forests
Relationships with habitat classifications. EUNIS: G3.4C Southeastern European [Pinus sylvestris] forests; PAL. CLASS.: 42.5C Southeastern European Scots pine forests; HD 92/43: 91CA Rhodopi and Balkan Range Scots pine forests; Bondev (1991): 18 Forests of Silver pine (Pineta sylvestris) forests, 19 Mixed Silver pine (Pinus sylvestris) and ordinary beech (Fagus sylvatica) forests, 20 Silver pine (Pinus sylvestris) and Balkan durmat (Quercus dalechampii) forests, 21 Silver pine (Pinus sylvestris) and Black pine (Pinus nigra) forests.
Conservation status. BDA, BC, HD.
Category. Nearly Threatened [NT – A1, 2 C3 D1 E1 F1 G1 H1 I L3].
General characteristics. The Scots pine forests are widely distributed in Bulgaria. They had different areas of distribution in the past but were most widely distributed during the Holocene (Sub-Boreal period). The contemporary coniferous forest belt with the participation of these forests developed during Atlantic period. The development and distribution of the Scots pine forests are the result of the following factors: natural succession processes, related to general aridisation and formation of the contemporary vegetation; anthropogenic pressure like fires, irregular logging, grazing, tourism; eco-physiological features of the Scots pine and the competing tree species. Autochthonous communities (or fragments of such communities) occur mainly on the southern slopes of Rhodopi, Rila, Pirin, Ossogovo Mts., and have more limited distribution in Plana, Vitosha, Lozenska, Slavyanka and Ograzhden Mts. and the Balkan Range. Scots pine coenoses which are under strong anthropogenic impact or are of secondary origin are also widely distributed in Bulgaria. Some of them have replaced forests of Picea abies, Abies alba, Pinus peuce and at lower altitude in the mountains, the forests of Fagus sylvatica and Quercus dalechampii in which the Scots pine used to participate with single trees. The largest areas covered by these secondary coenoses of the Scots pine occur in the Rila-Rhodopi mountain massif but mainly in Central and West Rhodopi Mts. Their secondary origin is confirmed by the thinner canopy of the forests, the large projective cover of the herbaceous synusia and the participation of mobile species the area of distribution of which is secondarily expanded in Bulgaria. The participation of other tree species (spruce, fir, beech) especially in the understory of these coenoses is an indication for their dynamic status.
The Scots pine forests cover mainly sunny slopes, on Cambisols and acidic bedrocks. Their distribution on humus-carbonate soils (Rendzic Leptosols) and marble is more limited. Two subtypes of Scots pine forests exist according to the acidity of the soils and the species that occur in them.
1. Scots pine forests on acidic soils (Vaccinio-Piceetea). The ecological plasticity and wide geographic range of the Scots pine as well as the secondary origin of some of its coenoses that occur on acidic soils make their syntaxonomic classification difficult. The acidophilic herbaceous species that occur in the Scots pine coenoses are widely distributed in other coenoses which have developed on acidic soils and are not particularly dependent on the canopy density. There are no specific species that can be associated with Pinus sylvestris within its large area of distribution. Very often it is not possible to distinguish the primary Scots pine coenoses from the secondary ones. A number of species typical for the class Vaccinio-Piceetea, order Piceetalia excelsae and alliance Piceion excelsae occur in the Scots pine forests on acidic soils. The association Digitali viridiflorae-Pinetum sylvestris has been described from E Rila and W Rhodopi Mts. Its coenoses occur in the remaining parts of Rila Mts., West Rhodopi Mts. and Pirin Mts. In these mountains, as well as in the whole area of distribution of these coenoses in Bulgaria, most probably other coenoses exist which need to be identified and described.
The Scots pine forests have a specific outlook and spatial structure. They consist mostly of two layers – a well defined tree layer and a herbaceous layer. Together with the Scots pine (Pinus sylvestris), Picea abies, Abies alba, Fagus sylvatica, Pinus peuce also participate in the composition of the tree layer, as co-dominants. More rarely Quercus dalechampii. Single trees of Betula pendula, Populus tremula, and Sorbus aucuparia also occur. In some communities, where the projective cover is lower, a shrub layer also develops, mainly with Juniperus communis and Chamaecytisus absinthioides. Chamaecytisus austriacus, Rubus hirtus, R. idaeus, Rosa pendulina also often occur. Main dominants in the herbaceous layer are Calamagrostis arundinacea, Deschampsia flexuosa, Luzula luzuloides, Vaccinium myrtillus and V. vitis-idaea. Aremonia agrimonoides, Campanula persicifolia, Chamaecytisus austriacus, Cruciata glabra, Dactylis glomerata, Dicranum scoparium, Digitalis viridiflora, Euphorbia amygdaloides, Fragaria vesca, Hieracium murorum gr., H. vulgatum gr., Hypericum perforatum, Moehringia pendula, Rhytidiadelphus triquetrus, Veronica officinalis, Viola reichenbachiana, V. riviniana are constant species. Local co-dominants and subdominants can be Bruckenthalia spiculifolia, Poa nemoralis, Pteridium aquilinum, Sanicula europaea, and Trifolium medium.
2. Scots pine forests on limestone (Erico-Pinetea). The Scots pine forests on limestone belong to class Erico-Pinetea. They have not been studied properly in Bulgaria. Fragments of these forests occur in Pirin, West Rhodopi and Slavyanka Mts. at 1100–1400 m alt. Most often these forests are monodominant, but can also be mixed with Pinus nigra. The following shrub species occur: Chamaecytisus hirsutus, Juniperus oxycedrus and Rosa pimpinellifolia. Brachypodium pinnatum, Festuca penzesii, Genista januensis, G. rumelica, Helianthemum nummularium, Pyrola chlorantha, Sesleria latifolia, Thymus pannonicus, T. sibthorpii,and other calcicole species occur in the herbaceous layer.
Characteristic taxa.
- Vascular plants: 1. Aremonia agrimonoides, Betula pendula, Bruckenthalia spiculifolia, Calamagrostis arundinacea, Campanula persicifolia, Chamaecytisus absinthioides, C. austriacus, Cruciata glabra, Dactylis glomerata, Deschampsia flexuosa, Digitalis viridiflora, Euphorbia amygdaloides, Fagus sylvatica, Fragaria vesca, Hieracium murorum gr., H. vulgatum gr., Hypericum perforatum, Juniperus communis, Luzula luzuloides, Moehringia pendula, Picea abies, Pinus sylvestris, Poa nemoralis, Populus tremula, Pteridium aquilinum, Quercus dalechampii, Rosa pendulina, Rubus hirtus, R. idaeus, Sanicula europaea, Trifolium medium, Vaccinium myrtillus, V. vitis-idaea, Veronica officinalis, Viola reichenbachiana, V. riviniana etc; mosses – Dicranum scoparium, Rhytidiadelphus triquetrus; 2. Brachypodium pinnatum, Chamaecytisus hirsutus, Festuca penzesii, Galium lucidum, Genista carinalis, G. januensis, Helianthemum nummularium, Hieracium praealtum, Jovibarba heuffelii, Juniperus communis, J. oxycedrus, Pinus nigra, P. sylvestris, Pyrola chlorantha, Sedum ochroleucum, Sesleria latifolia, Teucrium chamaedrys, Thymus pannonicus, T. sibthorpii etc.
- Fungi: Macromycetes – Albatrellus pes-caprae, Antrodia vaillantii, Auriscalpium vulgare, Boletus pinophylus, Choiromyces meandriformis, Chroogomphus rutilus, Clavariadelphus ligula, Clitocybe brumalis, C. phyllophila, C. vermicularis, Coltricia perennis, Cortinarius glaucopus, Craterellus cornucopioides, Ditiola radicata, Elaphomyces granulatus, Fomitopsis pinicola, Gomphidius roseus, Gyromitra esculenta, G. gigas, Heterobasidion annosum, Heyderia abietis, Hygrophorus erubescens, H. hypothejus, Lachnellula subtilissima, Lactarius deliciosus, Leucocortinarius bulbiger, Mycena galopus, Parmastomyces transmutans, Paxillus atrotomentosus, Phaeolus schweinitzii, Phellinus nigrolimitatus, P. pini, P. viticola, Phellodon niger, Pisolithus arrhizos, Pluteus atromarginatus, Rhizopogon luteolus, R. roseolus, Rozites caperatus, Russula coerulea, R. sardonia, R. vinosa, Sarcosphaera coronaria, Sparassis crispa, Spathularia flavida, Strobilurus stephanocystis, Suillus bovinus, S. luteus, S. variegatus, Tricholoma colossus, T. flavovirens, T. focale, T. imbricatum, T. portentosum, T. terreum, Tricholomopsis rutilans, Tylopilus pseudoscaber, Tympanis pinastri; Micromycetes – Cenangium ferruginosum, Lophodermium pinastri (on Pinus sylvestris), Exobasidium myrtilli, Podosphaera myrtillina (on Vaccinium myrtillus), E. vaccinii (on V. vitis-idaea), Gymnosporangium cornutum, Lophodermium juniperinum (on Juniperus communis), Podosphaera fusca (on Melampyrum sylvaticum), Ustilago luzulae (on Luzula luzuloides), U. striiformis (on Calamagrostis arundinacea).
- Animals: Invertebrates – Robertus mediterraneus, Formica transcaucasica; Vertebrates – Turdus viscivorus, Regulus regulus, R. ignicapillus, Parus montanus, P. ater, Carduelis spinus, Loxia curvirostra, Sorex araneus, Dryomys nitedula, Clethrionomys glareolus.
Distribution in Bulgaria. The Scots pine forests are mainly distributed in Rhodopi, Rila, Pirin and Osogovo Mts. and to a more limited extent in Central Balkan Range, Plana, Vitosha, Lozenska, Slavyanka and Ograzhden Mts., between 700 and 2000 m alt.
Conservation importance. The natural Scots pine forests cover relatively large areas approx. 120 000 ha. Their conservation importance is due to the fact that Bulgaria is the southernmost area of their distribution. Some vascular plants with conservation status occur: Diphasium complanatum (probably extinct), Genista rumelica, Goodyera repens, Jovibarba heuffelii, Listera cordata, Pyrola media etc., as well some fungi of conservation importance: Agaricus squamulifer, Albatrellus pes-caprae, Antrodia vaillantii, Auriscalpium vulgare, Buchwaldoboletus lignicola, Choiromyces maeandriformis, Clavariadelphus ligula, Clavicornia pyxidata, Clitocybe vermicularis, Cortinarius caesiocanescens, Ditiola radicata, Elaphomyces granulatus, Gomphidius roseus, Gyromitra gigas, Hygrophorus erubescens, Leucortinarius bulbiger, Parmastomyces transmutans, Phellinus nigrolimitatus, P. viticola, Pisolithus arhizos, Plectania melaeana, Rozites caperatus, Sarcosphaera coronaria, Sparassis crispa, Spathularia flavida, Tricholoma colossus, T. focale, Tylopilus pseudoscaber.
Threats. Intentional fires, unregulated logging, overexploitation of wood, grazing by domestic animals, unregulated tourism. Some natural processes also have negative impact like fires, wind storms, snow storms, global warming, etc.
Conservation measures taken. The habitat is included in Annex № 1 of BDA. Part of the Scots pine forests are within protected areas: Rila, Pirin and Central Balkan National Parks, Dupkata, Beglika, Centralen Rilski, Ibar Strict Nature Reserves, Srednite Livadi Protected Site and sites from the European Ecological Network NATURA 2000. Selective forestry systems for management have been applied in a part of the Scots pine. Parts of the Scots pine forests are within internationally certified forest units.
Conservation measures needed. Elaboration of forest-typological scheme in order to achieve a more effective and nature-friendly forest management. Mapping and monitoring of the better preserved and most vulnerable habitats and improvement of the forest protection activities.
References.Dimitrov 2003; Horvat et al. 1974; Kelly & Connolly 2000; Palamarev 1997; Peev et al. 1969; Roussakova & Dimitrov 2005.
Authors: Marius Dimitrov, Veska Roussakova
