12C2
Waterfalls
Relationships with habitat classifications. EUNIS: C2.24 Waterfalls; PAL. CLASS.: 24.17 Waterfalls.
Conservation status. None.
Category. Vulnerable [VU – A2 B2 C1 D2 E2 F1 G1 H2 I J L2].
General characteristics. Characteristic for this habitat type is the vertical fall of running water on one or several plains, thus the water continuum is terminated. The substrate rocks are of different types – granite, limestone, marble, travertine. The rocks are of different height with slope varying between 70o and 90o. As a result of the strong turbulence of the water fall it is very well aerated: the oxygen content is 9–10 mg/dm3. The high humidity and aeration create specific conditions for the development of hygrophytic vegetation and stenoxybionts that are highly specialized hydrobionts (mainly attached invertebrates resistant to the strong water pressure). The highest waterfall on the Balkans is in Bulgaria: Raiskoto Praskalo waterfall on Praskalska River, below Botev peak in Central Balkan Range. The water fall is 124.5 m high.
Characteristic taxa.
- Plants: Mosses – on silicate rocks often occur Hygrohypnum spp., Platyhypnidium riparioides, Racomitrium spp., Scapania undulata; on limestone rocks: Chiloscyphus polyanthos, Cinclidotus aquaticus, C. fontinaloides, C. riparius, Cratoneuron spp., Fissidens crassipes.
- Animals: Crustacea: Attheyella crassa, Bryocamptus zschokkei, Eucyclops serrulatus, Paracyclops fimbriatus; larvae of Ephemeroptera: Ameletus spp., Epeorus spp., Baetis spp.;Diptera: Simulidae, Euparipus spp., Trichoptera etc.
Distribution in Bulgaria. High to medium-high parts of Rila, Pirin, Rhodopi, Vitosha, Zemenska mountains, Balkan Range, Forebalkan.
Conservation importance. The habitat is important for the maintenance of the biodiversity of certain communities and species of high conservation importance. They are the ecotone zone and the physical barrier for longitudinal migration and distribution of specifically adapted water animals.
Threats. Tourism, water industry (leading away of water) and the construction of small water power stations.
Conservation measures taken. Some of the waterfalls are within protected areas: Rila, Pirin and Central Balkan National Parks, and Vitosha Nature Park and sites from the European Ecological Network Natura 2000.
Conservation measures needed. Regulation of the tourist flow, prohibition of activities that can cause a reduction of the water quantities in the related rivers and changes in the natural state of the waterfalls. Restoration activities in the affected areas.
References. Kovachev 2000; Stoichev1996; Vannote et al. 1980; Videnova et al. 2000.
Authors: Jordan Uzunov, Dimitar Kozhuharov
