06G1
Willow-poplar galleries in South Bulgaria
Relationships with habitat classifications. EUNIS: G1.3155 Rhodopi Mediterranean poplar galleries; PAL. CLASS.: 44.6155 Rhodopi Mediterranean poplar galleries; HD 92/43: 92A0 Salix alba and Populus alba galleries; Bondev (1991): 143 Black alder (Alneta glutinosae), willow (mostly Saliceta albae, Saliceta fragilis) and poplar (Populeta nigrae, Populeta albae) forests, partly combined with artificial poplar plantations and hydrophilous grass communities (in S Bulgaria).
Conservation status. BDA, HD.
Category. Vulnerable [VU – A1, 2 B1 C1 D2 E2 F1 G1 H1 I J L2].
General characteristics. Riverside forests that occur in the lowlands at the conditions of transitional continental climate in South Bulgaria. They occupy narrow stripes along the big rivers (Maritsa, Toundzha, Struma, Mesta rivers) and their feeders. The galleries develop on rich alluvial (sediment) soils (Fluvisols). Spring floods with different prolongation are typical. Main ediphicators are the White poplar (Populus alba), Black poplar (P. nigra), White and Fragile willows (Salix alba, S. fragilis). The Common alder (Alnus glutinosa), rarely Field elm (Ulmus minor), Field ash (Fraxinus oxycarpa), Oriental plantane (Platanus orientalis) and Common oak (Quercus robur) also occur. The participation of liana species, Humulus lupulus, Clematis vitalba, C. viticella, Hedera helix, Rubus spp., Periploca graeca, Calystegia sepium, Vitis sylvestris is typical. In most cases the habitats are subject to anthropogenic pressure due to the cultivation of the highly reproductive plantations of hybrid poplars. In the shrub-herbaceous layer there are many mobile species and anthropophytes: Aegopodium podagraria, Aristolochia clematitis, Berula erecta, Bidens tripartita, Bromus sterilis, Chelidonium majus, Galium aparine, Heracleum ternatum, Parietaria erecta (= Parietaria officinalis), Solanum dulcamara, Urtica dioica, etc. The willow-poplar galleries in South Bulgaria differ from the riverside willow-poplar forests of North Bulgaria by the presence of more species of southern origin: Bryonia alba, Clematis flammula, C. viticella, Parietaria erecta, Periploca graeca, Platanus orientalis, Salix xanthicola, Tamarix tetrandra, etc.
Syntaxonomically the willow-poplar galleries belong to class Populetea albae, order Populetalia albae and alliances Populion albae and Salicion albae.
Characteristic taxa.
- Vascular plants: Aegopodium podagraria, Alnus glutinosa, Aristolochia clematitis, Berula erecta, Bidens tripartita, Brachypodium sylvaticum, Bromus sterilis, Bryonia alba, Calystegia sepium, Chelidonium majus, Clematis viticella, Cornus sanguinea, Galium aparine, Heracleum ternatum, Humulus lupulus, Lycopus europaeus, Lysimachia nummularia, Lythrum salicaria, Mentha aquatica, Parietaria erecta, Periploca graeca, Phragmites australis, Platanus orientalis, Populus alba, P. nigra, Prunella vulgaris, Pulicaria dysenterica, Rubia tinctorum, Rubus spp., Salix alba, S. fragilis, Solanum dulcamara, Tamarix ramosissima, T. tetrandra, Typha latifolia, Ulmus minor etc.
- Fungi: Macromycetes – Auricularia mesenterica, Agrocybe cylindracea, Coriolopsis trogii, Ganoderma lipsiense, Coprinus disseminatus, Lactarius controversus, Laetiporus sulphureus, Morchella esculenta, Oxyporus populinus, Phellinus igniarius, P. pilatii, Ptychoverpa bohemica, Pholiota populnea, Polyporus squamosus, Tricholoma populinum; Micromycetes – Diplodia melaena, Uncinula clandestina (on Ulmus minor), Erysiphe adunca, Melampsora salicis-albae (on Salix alba), Melampsora allii-populina, Septoria populi (on Populus nigra), M. populnea (on Populus alba and P. nigra).
Distribution in Bulgaria. The southernmost parts of the country, but mostly along Maritsa, Struma, Mesta and Toundzha rivers and their feeders, from 50 up to 200 m alt.
Conservation importance. Rare phytocoenoses with vascular plants of conservation value (Platanus orientalis, Salix xanthicola, Samolus valerandi, Saponaria stranjensis, Satureja pilosa, Sedum grisebachii, Stachys thracica, etc.) as well as with fungi with conservation value (Phellinus pilatii, Ptychoverpa bohemica).
Threats. Afforestation with exotic tree species and cultivars, logging, waste disposal and water pollution; invasion of alien species (Acer negundo, Amorpha fruticosa, etc.); development of parasitic plants (Viscum spp.); agricultural activities such as transformation of riverside forests into cultivated land, grazing; redirection and clearing of the river beds.
Conservation measures taken. The habitat is included in Annex № 1 of the national Biodiversity Act. One of its localities is within Rupite Protected Site. Parts of the habitat are in sites of the European Ecological Network NATURA 2000 in Bulgaria.
Conservation measures needed. Detailed phytocoenological studies; extension of the borders of the protected areas in which parts of the habitat occur; development of forest-typological scheme aimed at more effective and nature-friendly forest management; mapping and monitoring of the habitats.
References. Bondev 1991.
Authors: Marius Dimitrov, Alexandar Tashev
