22G1
Montpellier maple (Acer monspessulanum) forests
Relationships with habitat classifications. EUNIS: G1.7C34. Moesian thermophilous maple woods; Pal. Class.: 41.834. Moesian thermophilous maple woods; Bondev (1991): 116 Acereta monsessulani forests, mixed mostly with flowering ash (Fraxinus ornus) and Oriental hornbeam (Carpinus orientalis), partly of secondary origin.
Conservation status. BC.
Category. Endangered [EN – A1, 2 B1 C2 D2 E2 F2 G2 H I J L2].
General characteristics. This habitat is represented by communities of Acer monspessulanum, which have a Mediterranean origin and are distinguished by a xerophytic nature. Acer monspessulanum is a tree that reaches 8–10 m with opposite, leathery, shiny, and trifid leaves. The wings of the fruits are parallel to each other with almost entire margins. The communities of Acer monspessulanum in the West Forebalkan usually occupy 15–30° slopes from (200) 600 up to 1000 m alt. The slopes are southern or with southern component. The main rock is limestone and the soil is humus-carbonate (Leptosols Rendzic), shallow, with outcrops of the main rock.
In the southern parts of the country, especially in regions with lower altitude, communities of Acer monspessulanum are not so strictly attached to calcareous grounds and shallow soils. This is explained by the warmer climate in these parts (transitional Mediterranean type). In East Rhodopi Mts. the communities of Acer monspessulanum occupy steep to very steep screes on volcanic rocks.
Acer monspessulanum constitutes pure or mixed communities or participate as a component of other deciduous tree phytocoenoses exclusively in the xerothermic oak belt. The ecological features of the coenoses of Acer monspessulanum affiliate them to the xerophytic vegetation. This stems both from the environmental characteristics of the species (Acer monspessulanum is a thermophilic species) and the tree, shrub and herbaceous species that participate in its communities: Bothriochloa ischaemum(= Dichanthium ischaemum), Brachypodium pinnatum, Carpinus orientalis, Cotinus coggygria, Melica ciliata, M. uniflora, Quercus pubescens, Syringa vulgaris,Vincetoxicum hirundinaria, etc. Wider distribution of mesophytic species (Carex brevicollis, Geranium macrorrhizum, Piptatherum virescens, etc.) can be observed in places where the relief creates conditions for maintaining higher air humidity.
The coenoses of Acer monspessulanum in Bulgaria have been studied only by applying the dominant method for vegetation classification. In the Forebalkan and Vrachanska Mts. seven associations have been described belonging to the formation Acereta monspessulani.
Characteristic taxa.
- Vascular plants: Acer monspessulanum,Bothriochloa ischaemum(= Dichanthium ischaemum), Carex brevicollis, Carpinus orientalis, Cornus mas, Crataegus monogyna, Fragaria vesca, Fraxinus ornus, Geranium macrorrhizum, Piptatherum virescens, Quercus pubescens, Syringa vulgaris, Viola alba.
- Animals: Eptesicus serotinus, Nyctalus noctula, Pipistrellus nathusii, P. pipistrellus.
Distribution in Bulgaria. West Forebalkan (near Belogradchik, Montana, Vrachanska mountain), the Struma river valley and East Rhodopi Mts.; up to 600 m alt.
Conservation importance. The phytocoenoses of Acer monspessulanum are relic elements in the vegetation cover of the country. Relics (Acanthus balcanicus, Carex brevicollis, Corylus colurna, Ferula heuffelii, Syringa vulgaris) and rare (Ferula heuffelii, Festuca balcanica, Achnatherum calamagrostis) plants participate. The Balkan endemic Ramonda serbica occurs in some places in the forests of Acer monspessulanum in West Forebalkan, near Gorna Verenitza village.
Threats. In many places the communities of Acer monspessulanum are strongly decreased because the forests have been destroyed by various economic activities, including the uncontrolled felling or natural succession processes. Parts of the coenoses were converted into open (sparse) forests. Due to its good mechanical properties the wood of the species was used in the past by the local people for the manufacture of various household goods.
Conservation measures taken. Parts of the communities of Acer monspessulanum are within the borders of Vrachanski Balkan Nature Park and in sites of the European Ecological Network NATURA 2000 in East Rhodopi Mts, West Forebalkan and the Struma River valley.
Conservation measures needed. Monitoring of the representative coenoses and proclamation of protected areas to conserve the habitat.
References. Velchev 1971; Velchev et al. 1965; Velchev & Bondev 1984b.
Author: Vladimir Valchev
