National park Tsentralen Balkan: Flora
About 2 337 species and subspecies comprising about 1900 species and subspecies of vascular plants, 188 species and subspecies of algae, 229 species of bryophytes, 15 species of Polypodiaceae, 1 species of Lycopodia, 1 species of Selaginellae and 3 species of Equisetophyta are established on the territory of the park. They represent over 50 % of the Bulgarian floristic diversity.
There are six complete or incomplete vegetation belts in the Central Balkan National park: belt of xeroterm oak forests, belt of xeromesophyllic and mesophyllic oak and hornbeam forests, beech belt, coniferous belt, belt of subalpine vegetation, dwarf-pine and juniper thickets and alpine belt.
Forests occupy about 56% of the whole park`s territory. The deciduous forests are 86% of the total area covered with forests.
Belt of xeroterm oak forests – it comprises the lowest parts of the park territory at altitude range from 550 to 650 m a.s.l. In some places it can be found up to 800-900 м a.s.l. The belt is situated on the southern slopes only. Moss-capped oak, Hungarian oak and swamp white oak are dominant in the tree communities. Secondary communities of hornbeam are formed over large areas in the place of the felled oak forests. Carpinus betulus and in some places Pinus nigra are common in the belt. The compact communities of Juniperus oxicedrus are also of interest.
Belt of xeromesophyllic and mesophyllic oak and hornbeam forests – it comprises the parts of the park that are up to 800-900 m a.s.l., mainly on the southern slopes. It is a complete belt. The communities of Quercus robur, Carpinus betulus and Carpinus orientalis predominate. The formations of Fraxinus ornus, Tilia agrentea and Ostrya carpinifolia are not so common.
Belt of beech forests – it covers the parts of the park, which are at altitude range from 800 to 1600 m a.s.l. It is situated almost evenly on both mountainsides. In some places a south-north territorial connection is established. This belt is of incomplete type. Here and there the beech forests form massifs (1 000 – 3 000 hа). The beech is the main species active in the influencing environmental conditions. The beech forests cover 44% of the park territory. They occupy roughly 60 000 ha together with the forests in the close proximity of the park and represent the largest and most compact massifs of this type in Europe relatively unsubjected to anthropogenic impact. The average age of the beech communities is 135 years.
The fir-tree formation is typical of the beech belt. It covers large areas on the northern slopes and has fragmented distribution on the southern mountain slopes.
Belt of coniferous forests – they are of fragmented distribution and do not form an incomplete belt within the park limits. The spruce formation is the most widely distributed one. The natural habitat of the Balkan endemic white-fir, which is the northernmost habitat in the world and the only one in Stara Planina, is situated in the plot between Kartala and Yumruka peaks.
Belt of subalpine vegetation, dwarf-pine and juniper thickets – it is situated along the timberline between 1 500 and 1 850 m a.s.l. near the mountain ridge. The vegetation cover of this belt includes widely distributed shrub formations of Juniperus Sybirica, Vaccinium myrtillus, Bruckenthalia spiculifolia. Rubus idaeus, Pinus montana, Arctostaphylles uva-ursi are not very common. The dwarf-pine is of special interest. Its only habitat in Central Stara Planina known to date is situated within the park limits.
As a result of the intensive grazing regime in the past the vegetation cover has undergone successional changes that lead to sustainable communities of Nardus stricta covering large areas. Grazing and fires limited the distribution of juniper.
Alpine belt – it is of fragmented type on the highest ridges and peaks – Botev peak, Vejen peak, Ambaritsa peak, Triglav peak etc. The formations of Arctostaphylos uva-ursi, Agrostis rupestris, Juncus trifidus and Carex curvula are characteristic of the alpine vegetation
The park includes groups of taxa of high conservation significance – protected by law, local, Bulgarian and Balkan endemics, species included in the Red Data book of Bulgaria, the Red European list and the IUCN list of endangered species.
Local endemics: Alchemilla achtarovii, Alchemilla asteroantha, Alchemilla jumrukczalica, Micromeria frivaldszkyana, Primula vulgaris, Stachys bulgarica, Veronica chamaedrys, Viola balcanica, Centaurea, Silene balcanica, Saturefa hortensis.
Rare: Acer heldreichii, Alchemilla bulgarica, Alchemilla achtarovii, Alchemilla jumrukczalica, Alchemilla catachnoa, Alchemilla asteroantha, Alchemilla Alchemilla gracillima, Angelica pancicii, Arctostaphylles uva-ursi, Drosera rotundifolia, Laurocerasus, Stachys bulgarica, Atropa bella-donna, Asperula capitata, Centaurea kernerana etc.
Endangered: Alchemilla mollis, Gentiana lutea, Gentiana punctata, Gentiana acaulis, Verbascum thapsiforme, Galanthus nivalis etc.
Protected by the Nature protection law: Anemone narcissiflora, Centaurea kernerana, Verbascum thapsiforme Schard., Daphne blagayana, Drosera rotundifolia, Galanthus nivalis, Juniperus sabina, еделвайс, Lilium jankae, Primula vulgaris, Rhodiola hosea L., Rhododendron myrtifolium, Rhynchocorys elephas etc.
Species included in CITES list: Galanthus nivalis, Orchidaceae.
Species included in the European Red list of endangered species: Centaurea kernerana, Primula vulgaris, Sedum stefco, Sempervivum erythraeum, Viola balcanica, Seseli bulgaricum, Dianthus stribrnyi etc.
Species included in the IUCN list: Campanula transsilvanica, Anthemis sancti-johannis, Haberlea rhodopensis, Alchemilla asteroantha, Alchemilla indivisa.
According to literary data, the bryoflora of the park comprises 229 species, which represent 34% of the species and 62% of the families in Bulgaria. Two species are included in the Red Data book of European bryophytes. 7 species are in the list of endangered bryophytes in Bulgaria.
Five species of prokaryote and eukaryote algae are found in Saragiol – the only lake in the park. This is the only habitat of Osscilatoria ingrica in the park, so the species is considered rare and locally threatened with extinction.