04B1
Relationships with habitat classifications. EUNIS: B1.4B11 Southwestern Pontic fixed dunes, B1.4B12 Northwestern Pontic fixed dunes; PAL. CLASS.: 16.22B11 Southwestern Pontic fixed dunes, 16.22B12 Northwestern Pontic fixed dunes; HD 92/43: 2130 *Fixed coastal dunes with herbaceous vegetation (grey dunes); Bondev (1991): 147 Psammophytous grass communities with a dominance of mostly Leymeta racemosi, Ammophylleta arenariae, Galileeta mucronata, Centaureeta arenariae, Trachomitum venetum and shrub communities with a prevalence of Cionureta erectae and others mostly on the coastal sands.
Conservation status. BDA, BC, HD.
Category. Endangered [EN – A1, 2 C3 D2 E2 F2 G2 H3 I L3].
General characteristics. Fixed coastal dunes stabilized and colonized by many diverse coenoses dominated by perennials and with abundant lichens and mosses in some areas. They are distributed along the whole Black Sea coast, but mostly to the South of the estuary of Kamchia River. Northwards, near Durankulak Lake, there is a small, isolated area with grey dunes that differ significantly from the remaining stabilized dunes in Bulgaria. It can be regarded as the southernmost place of distribution of the northwestern Pontic fixed dunes (B1.4B12) that occur mainly in the Danube delta (Romania and Ukraine). Because of their specificity the two types of grey dunes in Bulgaria are treated separately:
1. Southern Pontic Grey Dunes (community Aurinio uechtritziani-Artemisietum campestris). These are fixed dune systems whose vegetation belongs to the alliance Sileno thymifoliae-Jurinion kilaeae thatisendemic to the Black Sea coast. In Bulgaria they are represented mainly by the association Aurinio uechtritziani-Artemisietum campestris, distributed southwards from the estuary of Kamchia River. This habitat includes dune complexes with differ in size and height – from 2–3 m up to 50 m alt. (the highest dune is in Kaya Cape, to the North of Ropotamo River). They are classified in different types depending on the tightness of the sand and its wetness. The coenoses of the association Pancratietosum maritimi occur in the transitional zone to the embryonic dunes, mostly with eastern exposure and on more mobile sands, where the prevailing species are typical mainly for the mobile dunes – Ammophila arenaria, Eryngium maritimum, Leymus racemosus subsp. sabulosus, Medicago marina, Pancratium maritimum. The typical subassociation is most widely distributed. The following species are characteristic for the grey (fixed) dunes: Artemisia campestris, Centaurea arenaria, Cionura erecta, Jurinea albicaulis subsp. kilaea, Lepidotrichum uechtritzianum (= Aurinia uechtritziana), Linaria genistifolia, Silene euxina, Teucrium polium. Galilea mucronata, Linum tauricum subsp. bulgaricum, Peucedanum arenarium occur in the coenoses on the western slopes of the dune systems.Annuals occur principally on the more mobile sands, usually on the ridges of the dunes (Arenaria serpyllifolia, Corispermum nitidum, Secale sylvestre), while on the northern, wet slopes, many mosses and lichens occur (Cladonia foliacea, C. subrangiformis, Grimmia pulvinata, Syntrichia ruralis, Tortella flavovirens). The most fixed wet sands at the depressions in the dunes are covered by the coenoses of the association Stachyo atherocalici-Caricetum ligericae,for which the following species are typical: Carex ligerica, Chondrilla juncea, Jasione heldreichii, Stachys atherocalyx.These coenoses are transitional to the humid dune depressions (see over-wet and flooded dune slacks). Fragments of the xerothermic coenoses of Chrysopogon gryllus appear on the most stabilized places of the grey dunes where the process of soil formation is more advanced.
2. Northern Pontic Grey Dunes (association Alysso borzaeani-Ephedretum distachyae). The coenoses of these dunes belong to the alliance Scabiosion ucrainicae. They are represented in Bulgaria only by the endemic association Alysso borzaeani-Ephedretum distachyae,that occurs in St. Ana Maria locality very close to the Romanian border. They are low (about 1 m above the beach level), stabilized dune complexes covered by perennial herbaceous vegetation. The coenoses of Ephedra distachya with high projective cover are very typical. The following species also occur: Alyssum borzaeanum, Cynanchum acutum, Erysimum diffusum, Festuca vaginata, Scabiosa argentea, Silene thymifolia, Verbascum purpureum.The participation of mosses (Syntrichia ruralis), lichens (Xanthoria parietina), some ruderals (Echium vulgare, Marrubium peregrinum) and even single shrubs (Prunus spinosa) is typical.
Characteristic taxa.
Distribution in Bulgaria. Black Sea coast – northern Pontic fixed (grey) dunes have been established only northwards from Durankulak Lake (Anna Maria locality); southern Pontic fixed (grey) dunes are very widely distributed – Kamchiya River, Shkorpivolvtsi village, Sunny Beach resort, Nessebar, Gradina-Zlatna Ribka, and Kavatzite camping places, Alepou, Arkutino, Stomopolou swamps, Primorsko-Kiten area.
Conservation importance. The syntaxa of the grey dunes are endemic to Bulgaria. Particularly unique is the association Alysso borzaeani-Ephedretum distachyae that occurs only on the beach of St Ana Maria locality. Tens of rare, endemic and protected species participate in the coenoses of the Pontic fixed (grey) dunes whose populations progressively decrease in Bulgaria. Such are Alyssum borzaeanum, Lepidotrichum uechtritzianum (= Aurinia uechtritziana)(Balkan-Anatolian endemic), Centaurea arenaria, Linum tauricum subsp. bulgaricum, Pancratium martimum, Silene euxina, Verbascum purpureum, etc. Fungi of conservation significance are Clathrus archeri and Phallus hadriani.
Threats. Intensive development of tourism, urbanization, illegal restitution of the coastal sand stripe, building of temporary and permanent constructions on the dunes, pollution, tramping of the sand by tourists and destruction of the dune coenoses, illegal sand pits, natural dynamics of the mobile sand substrates, invasion of alien and ruderal species in the dune complexes such as Ailanthus altissima (in the area of Nessebar), Amorpha fruticosa, Elaeagnus angustifolia, Robinia pseudacacia,planting of alien species like Pinus maritima near Shkorpilovtsi village.
Conservation measures taken. The habitat is included in Annex № 1 of the national Biodiversity Act and is of conservation priority. Some localities are within the borders of existing protected areas – Kamchiyski Pyasatsi Protected Site (meanwhile deleted by VAC), Ropotamo Strict Nature Reserve and Pyasachna lilia Managed Nature Reserve Pyasachni Duni Nature Monuments in Alepou, Babata, Kavatzite, Gradina-Zlatna ribka localities, Perla locality, IYC Primorsko, near Nessebar and in sites from the European Ecological Network NATURA 2000.
Conservation measures needed. Termination of illegal construction activities, urbanization and degradation of the preserved dune complexes along the Black Sea coast, decreasing of the negative impacts of tourism, purposeful management of the NATURA 2000 zones aiming at the protection of the psammophytic coenoses, adoption of a law for the Black Sea coast.
References. Bondev & Velchev 1982; Davidov 1912; Meshinev et al. 1994; Tzonev et al. 2005; Vicherek 1971.
Author: Rossen Tzonev