21F3
Mediterranean fields of Rumelian green weed (Genista rumelica) and Lydian green weed (Genista lydia)
Relationships with habitat classifications. EUNIS: F3.29 Moesian broom fields; PAL. CLASS.: 31.848 Moesian broom fields; Bondev (1991): 124 Shrubs of Rumelian green weed (Genisteta rumelicae) (r) and of Lydian green weed (Genisteta lydiae) (l).
Conservation status. None.
Category. Vulnerable [VU – B1 B2 C1 D2 E2 F1 G1 H1 I J].
General characteristics. This habitat type comprises a complex of open shrub, herbaceous and hasmophytic plant communities dominated by Genista rumelica and Genista lydia. Genista rumelica is a Balkan endemic (occuring only in South Bulgaria and North Greece), and Genista lydia is a subendemic (occurs in Bulgaria, North Greece and the western parts of Asia Minor. The habitat is endemic to the southeastern part of the Balkan Peninsula. The communities of Genista rumelica are distributed mainly in the lower parts of the mountains of South-West Bulgaria (South Rila Mts., Pirin and Slavyanka Mts.) and Rhodopi Mts. (mainly their eastern part). To the North, isolated localities occur on the southern slopes of the Balkan Range (Kazanlak and Sliven regions) and Sredna Gora Mts. (Pazardzhik region). Localities of the habitat type under consideration occur also in the Thracian Lowlands (Plovdiv town and Assenovgrad region) and Strandzha Mts. (Brodilovo village).
The communities of Genista lydia are much rarer and occur in isolated localities only in South-East Bulgaria (Thracian Lowland, Toundzha Hilly Country, Strandzha Mts.). The biggest areas are in East Rhodopi Mts. especially in the vicinity of Zlatograd town (Chorbadzhiisko village).
The communities of Genista rumelica and G. lydia occur on steep, dry, stony and sunny places, on shallow soils (Rendzic, Umbric Leptosols and others.). The bedrock varies. However Genista rumelica prefers calcareous substrates. These communities can often occur on silicate rocks or sandstone, on slopes above rivers or in deep ravines. They can occupy secondary, degraded areas: screes and eroded places, replacing destroyed or degraded forest, mostly of different oak species (Quercus frainetto, Q. pubescens) or Black pine (Pinus nigra).
The two Genista species are short (up to 0,50–0,70 m high) shrubs. The leaves of Genista rumelica fall away after flowering, hence the plant and its coenoses have specific appearance. These communities are open and various species participate in them, including hasmophytes in the places with poorer soils and rock outcrops. Most of the herbaceous species are of Mediterranean or sub-Mediterranean origin, including many annual grasses such as Trachynia distachya(= Brachypodium distachyon), Bromus squarrosus, Poa bulbosa, Psilurus incurvus, etc. Perennial grasses also often occur like Chrysopogon gryllus, Cleistogenes serotina, Bothriochloa ischaemum (= Dichanthium ischaemum), Koeleria splendens, Stipa capillata. Other frequently occurring species are Alyssum murale, Eryngium campestre, Minuartia setacea, Orlaya grandiflora, Scabiosa ochroleuca, Sedum spp., Teucrium chamaedrys, Thymus spp. Some Balkan endemics and subendemics have high abundances such as Achillea coarctata, Dianthus pinifolius, Silene frivaldszkyana.Some shrubs and single trees also occur: Carpinus orientalis, Fraxinus ornus, Jasminum fruticans, Juniperus oxycedrus, Paliurus spina-christi, etc. Usually, these communities form complexes with elements from the neighbouring tree, shrub and pasture vegetation. The diverse floristic composition is also due to their various origin. The communities are related to unstable areas: screes, steep slope, small rivulets, and rocky substrates. This is the reason why these phytocoenoses are very plastic but the fact that they occupy limited areas, and the relic and endemic nature of their dominant species, as well as other species participating in them are the reason why they have conservation value.
Characteristic taxa.
- Vascular plants: Achillea coarctata, Alyssum murale,Trachynia distachya, Bromus squarrosus, Carpinus orientalis, Cephalaria laevigata, Chrysopogon gryllus, Cleistogenes serotina, Dianthus pinifolius, Bothriochloa ischaemum (= Dichanthium ischaemum), Fraxinus ornus, Genista lydia, G. rumelica, Jasmium fruticans, Juniperus oxycedrus, Koeleria spp., Melica ciliata, Minuartia setacea, Orlaya grandiflora, Poa bulbosa, Psilurus incurvus, Scabiosa ochroleuca, S. triniifolia, Sedum hispanicum, Silene frivaldszkyana, Stipa capillata, Teucrium chamaedrys, Thymus spp.
Distribution in Bulgaria. Central and East Balkan Range (Sliven and Kazanlak regions); Sredna Gora Mts. (Pazardzhik region); Pirin, South Rila, Slavyanka Mts.; the valley of Mesta river; Rhodopi Mts.(Devin, Dospat, Yundola, Smolyan, Chepelare, Bachkovo, Kardzhali, Ardino, Zlatograd towns); Thracian Lowland (Plovdiv, Haskovo regions), Toundzha Hilly Country (very rare) and Strandzha Mts.; between 150 and 1000 m alt.
Conservation importance. The habitat of the Mediterranean broom fields makes complexes with other rare communities, including these from Thero-Brachypodietea, which are priority habitats from Natura 2000. The dominants and some of the frequently occurring species (Dianthus pinifolius, Silene frivaldszkyana) in the communities under consideration are Balkan and Balkan-Anatolian endemics.
Threats. Direct destruction of the habitat as a result of resources exploitation; degradation as a result of grazing; fires; infrastructure development; natural instability of the habitat substrates.
Conservation measures taken. None. In some places the habitat is within sites of the European Ecological Network Natura 2000 in Bulgaria (South Pirin - Alibotush site; East Rhodopi site). However, no effective conservation measures have been undertaken because the habitat is not included in Annex № 1 of the national Biodiversity Act.
Conservation measures needed. Proclamation of some of the most representative localities of the habitat as protected areas (e.g. the localities near Chorbadzhiisko village, Eleshnitsa village, etc.); phytocoenological study and mapping of all broom scrub in Bulgaria.
References. Velchev & Bondev 1984a, b.
Authors: Rossen Tzonev, Chavdar Gussev
