16H3
Wet carbonate rocks with Black maidenhair fern (Adiantum capillus-veneris)
Relationships with habitat classifications. EUNIS: H3.43 Illyrio-Helleno-Balkan wet carbonate cliffs; PAL. CLASS.: 62.51 Mediterranean wet inland cliffs.
Conservation status. None.
Category. Critically endangered [CR – B1 C2 D3 E3 F2 G2 H3]
General characteristics. The habitat encompasses hasmophytic coenoses dominated by or with the participation of the Black maidenhair fern Adiantum capillus-veneris. These communities are very specific both for their phytogeographic distribution and the ecological conditions at which they occur. The phytocoenoses of the Black maidenhair fern belong to class Adiantetea distributed mainly in the Mediterranean. Hasmophytic coenoses with A. capillus-veneris occur only in the southernmost part of Bulgaria – East and Central Rhodopi Mts., Slavyanka Mts.; the only reported locality in West Bulgaria is near Zhilentsi village, Kyustendil region but has not been confirmed. The habitat is characterized by specific hydrological conditions. The phytocoenoses of the Black maidenhair fern occur on more or less wet, vertical, calcareous rocks. The water is mainly on the surface, running down the slopes from the above-situated small streams, karst springs, etc. The water running slowly down the rocks makes the formation of porous limestone (travertine) possible. Apart from A. capillus-veneris, the most frequently-occurring travertine-making moss species are the calcicole species Conocephalum conicum, Eucladium verticillatum, and Palustriella commutata.Since the habitat is found in shady places among the vascular plants, mainly hygrophytic, shade-resistant species occur like Epilobium spp., Eupatorium cannabinum, Mycelis muralis,etc. On the places that are more constantly watered green and blue-green algae also occur. All localities of the habitat are on very small areas and strongly depend on the period of watering. In dry conditions the phytocoenoses of the Black maidenhair fern become inactive. The possibilities for the plants to restore their normal functions depend on the meteorological conditions throughout the year.
Characteristic taxa.
- Vascular plants: Adiantum capillus-veneris, Brachypodium sylvaticum, Eupatorium cannabinum, Mycelis muralis; mosses – Conocephalum conicum, Eucladium verticillatum, Palustriella commutata.
Distribution in Bulgaria. East Rhodopi Mts. (near Kardzhali town – Kjosh-Dere locality and near Oreshari village); Slavyanka Mts. (Yanovo village), South Pirin Mts. (Kalimantsi village), Struma River valley (near Ilindentsi village); 200 – 1000 m alt.
Conservation importance. The localities are very small and isolated. Adiantum capillus-veneris is a critically endangered species from the Red List of Vascular Plants in Bulgaria and is protected by law.
Threats. Strong geographical isolation of the habitat, changes in the water regime due to various human activities – spring capturing, draining of waters running down the slopes, destruction of the neighbouring vegetation or its replacement by forest plantations, extraction of rock materials, etc.
Conservation measures taken. Some of the localities of the habitat are included in protected areas – Nahodiste na Venerin Kosam and Oreshari Protected Sites and sites from the European Ecological Network NATURA 2000.
Conservation measures needed. Permanent monitoring and investigation of the known localities; measures for the restoration of the water regime where it is disturbed.
References. Ivanova 2009.
Authors: Rossen Tzonev, Chavdar Gussev
The data validity refers to December 2007.
