06E1
Serpentine steppes
Relationships with habitat classifications. EUNIS: E1.2B Serpentine steppes; PAL. CLASS.: 34.37 Serpentine steppes.
Conservation status. BC.
Category. Endangered [EN – A1 C2 D2 E2 F2 G2 H2 L2].
General characteristics. This habitat type occurs in the belt of the xerothermic oak forests and covers a restricted area of ca. 15 ha in isolated places in the northern part of Central Rhodopi Mts., and Vlahina Mts. in SW Bulgaria. The soil most often is cinnamonic forest shallow and in many places with outcrops of serpentine rocks, that are a part of the pre-Cambrian crystalline complex. The rock metamorphosis that took place in the past had lead to a more diverse chemical composition of the serpentine rocks in Bulgaria. The high composition of iron is a typical feature of the pre-Cambrian vulcanites in Rhodopi Mts. Serpentine steppes are xerothermic, closed or semi-closed phytocoenoses, dominated mainly by Bothriochloa ischaemum(= Dichanthium ischaemum), Bromus squarrosus, Chrysopogon gryllus, Koeleria simonkaii, Melica ciliata, Poa bulbosa, Stipa capillata, S. tirsa,Trachynia distachya(= Brachypodium distachyon).The total projective cover of the herbaceous coenoses is on average ca. 60%. In some places serpentine outcrops occur. Some steppe species like Achillea depressa, Asperula cynanchica, Astragalus onobrychis subsp. chlorocarpus, Crupina vulgaris, Eryngium campestre, Goniolimon collinum, Inula ensifolia, Linum tenuifolium, Stachys angustifolia, Trinia glauca subsp. glauca, etc. participate in the plant communities.These plant communities are formed after the cutting down of the primary oak forests. They form complexes with remnants of forests of Quercus pubescens and Q. virgiliana, more rarely of Q. frainetto and Carpinus orientalis and scrub of Juniperus oxycedrus and Paliurus spina-christi, Cotinus coggygria, Pistacia terebinthus. Their flora is strongly xeromorphic, and is characterized by considerable morphological changes and population dispersity. Central European, sub-Mediterranean and Mediterranean floristic elements have played significant roles in the formation of the serpentine flora of Central Rhodopi Mts.
Characteristic taxa.
- Vascular plants: Achillea depressa, Asperula cynanchica, Astragalus onobrychis subsp. chlorocarpus, Asyneuma limonifolium, Bothriochloa ischaemum (= Dichanthium ischaemum), Chrysopogon gryllus, Dorycnium herbaceum, Festuca thracica, Goniolimon collinum, Hypericum rumeliacum, Inula aschersoniana, I. ensifolia, Iris reichenbachii, Koeleria simonkaii, Linum tenuifolium, Onosma thracica, Petrorhagia illyrica, Poa bulbosa, Stachys angustifolia, Stipa capillata, S. tirsa, Trinia glauca subsp. glauca.
- Fungi: Micromycetes – Microbotryum violaceo-verrucosum (on Silene bupleuroides), M. violaceum (on Silene vulgaris), Phragmidium potentillae (on Potentilla argentea), Puccinia cesatii, Sporisorium andropogonis (on Dichanthium ischaemum).
Distribution in Bulgaria. Vlahina Mts. (Seliste village – Ovnarska settlement and Stara Zheleznitza village – Murdzhova chuka peak, between 300 and 760 m alt.), South Pirin Mts. (Lyalevo village, Gotse Delchev area), Central Rhodopi Mts. – the area between Parvenetz village (to the South of the village, on both sides of Parvenetzka river) and Hrabrino village, Northeast of Markovo village and Southwest from Cherven village at 150–350 m alt.
Conservation importance. Some species have restricted distribution in Bulgaria, including protected ones. Some of the taxa are included in the Red Data Book of Bulgaria (Anthemis rumelica, Genista rumelica, Inula aschersoniana, Iris reichenbachii) and Annex №3 of the national Biodiversity Act, (Anthemis rumelica, Goniolimon collinum, Limodorum abortivum) and are protected. Endemics distributed in this habitat are Anthemis rumelica, Arenaria procera, Crucianella graeca, Delphinium balcanicum, Festuca thracica, Hypericum rumeliacum, Inula aschersoniana, Koeleria simonkaii, Scabiosa triniifolia, Verbascum nobile, etc.
Threats. Fragmented distribution on a small area; influence of the developing stock breeding and urbanization. Threats are grazing, trampling by cattle, planting of deforested areas, fires and deposition of household waste. As a result of the increased anthropogenic activities and the proximity of villages (Parvenetz, Markovo villages) the autochtnonous vegetation is degrading.
Conservation measures taken. Some of the plant communities near Parvenetz village (Brestovitza zone) and Zheleznitza village (Oranovski Prolom-Leshko zone) are included in the protected zones of the European Ecological Network NATURA 2000. Scientific studies have been also conducted such as floristic analysis, identification of species of conservation importance, chemical analysis of the soil and plant material, monitoring, etc.
Conservation measures needed. Proclamation of a protected area to preserve this habitat type near Parvenetz village.
References. Pavlova 2001, 2004, 2010.
Authors: Dolja Pavlova, Dimitar Dimitrov
