Balkan Vegetation
Total Page:16
File Type:pdf, Size:1020Kb
Plant Formations in the Balkan BioProvince Peter Martin Rhind Balkan Mixed Deciduous Forest These forests vary enormously but usually include a variety of oak species such as Quercus cerris, Q. frainetto, Q. robur and Q. sessiliflora, and other broadleaved species like Acer campestris, Carpinus betulus, Castanea sative, Juglans regia, Ostrya carpinifolia and Tilia tomentosa. Balkan Montane Forest Above about 1000 m beech Fagus sylvatica forests often predominate, but beyond 1500 m up to about 1800 m various conifer communities form the main forest types. However, in some cases conifer and beech communities merge and both reach the tree line. The most important associates of beech include Acer platanoides, Betula verrucosa, Corylus colurna, Picea abies, Pyrus aucuparia and Ulmus scabra, while the shrub layer often consists of Alnus viridis, Euonymous latifolius, Pinus montana and Ruscus hypoglossum. The ground layer is not usually well developed and many of the herbaceous species are of central European distribution including Arabis turrita, Asperula muscosa, Cardamine bulbifera, Limodorum abortivum, Orthilia seconda and Saxifraga rotundifolia. Of the conifer forests, Pinus nigra (black pine) often forms the dominant species particularly in Bulgaria, Serbia and in the Rhodope massif. Associated trees may include Taxus buccata and the endemic Abies bovisii-regis (Macedonian fir), while the shrub layer typically includes Daphne blagayana, Erica carnea and the endemic Bruckenthalia spiculifolia (Ericaceae). In some areas there is a conifer forest above the black pine zone from about 1300 m to 2400 m in which the endemic Pinus heldreichii (Bosnian pine) predominates. It is often rather open possibly as a consequence of repeated fires. However, the flora of this zone is often of great botanical interest with many Balkan endemics such as Asperula aristata subsp. thessala (Rubiaceae), Campanula oreadum and Edraianthus grammifolius (Campanulaceae), Cerastium banaticum (Caryophyllaceae), Gentiana verna subsp. pontica (Gentianaceae), Globularia albanica (Globulariaceae), Marrubium thessalum, Sideritis scardica and Teucrium montanum (Lamiaceae) and Viola delphinantha (Violaceae). Montane conifer forest dominated by the endemic Picea omorika (Omorika spruce) is much more restricted being confined to the central and upper parts of the Drina Basin in western Serbia and eastern Bosnia. Picea omorika is a typical Tertiary relict species of the Balkans. The undergrowth is not normally very well developed but may include Lonicera alpigena, Rhus cotinus and Spiraea cana. Fir forests are is also very local with the main species being either Abies alba or the endemic Abies cephalonica in the south. Abies alba forms almost pure stands in the area around Camkorija. Here they are often festooned with lichens, but the ground flora is often poor in vascular plants consisting mainly of mosses and liverworts. However, in some of the wetter areas endemics such as Cirsium appendiculatum (Asteraceae), Buphthalmum speciosum and Ranunculus serbicus (Ranunculaceae) occur. Abies cephalonica is confined to the Pindus Mountains where it can be found growing with other local endemic conifers such as Abies borisii, Pinus heldreichii and P. peuce (Pinaceae). Among the more notable relict endemic species also found here are Jankaea heldreichii and Copyright © 2010 Peter Martin Rhind Ramonda nataliae (Gesneriaceae), Macrotomia densiflora (Boraginaceae) and Primula kitaibeliana (Primulaceae). Balkan (Pannonic) Oak Woodland Fragments of woodland dominated mainly by different species of oak occur across the Pannonic zone. The most important species are Quercus cerris (Turkey oak), Q. frainetto (Hungarian oak) and Q. pubescens (White oak), but other species such as Q dalechampii, Q pedunculiflora and Q. polycarpa may also be encountered. Other characteristic trees are Acer tataricum, Carpinus betulus, C. orientalis, Tilia tomentosus and the endemic Fraxinus angustifolium subsp. pannonica (Oleaceae). Many of the canopy trees are deciduous and in the more natural examples the canopy tends to be very dense. Consequently, ground vegetation is at its best during springtime. Shrub layer species vary but may include Cotinus coggygria, Cornus mas, Euonymus verrucosus, Prunus mahaleb and Staphylea pinnata. Likewise the field layer varies but typical species may include Acillea coarctata, Ajuga laxmannii, Buglossoides purpurocaerulea, Helleborus odorus, Lathyrus pannonicus and the near endemic Cynoglossum hungaricum (Boraginaceae). Balkan Alpine Scrub Above the tree line between 1700 - 2500 m, Juniperus communis var. nana is the most frequent component of high mountain scrub throughout most of the central parts of the Balkan Peninsula. Other species often include Alnus viridis, Daphne oleoides, Genista tinctoria and Pinus mugo. On cooler damper slopes on acid soils, heath-like thickets of ericaceous shrublets predominate including Arctostaphylos uva-ursi, Vacccinium myrtillus, V. uliginosum, V. vitis-idaea and the endemic Balkan heath Bruckenthalia spiculifolia (Ericaceae). In fact, the latter species largely takes the places of Calluna vulgaris of north European moors and is somewhat similar in habit, flower colour and habitat. Rhododendrons are rare in the Balkan Peninsula but Rhododendron kotschyi occcus in the mountains of northern Macedonia. Balkan (Pannonic) Steppe Grassland The remains of natural steppe grassland typically occur on the so-called black earth soils where conditions are too dry for scrub or woodland. The most natural examples are dominated by Stipa species such as S. capillata and S. lessingiana, but these are now mainly confined to reserves such as the Steppe Nature Reserves of Fîntînita-Murfatlar in Romania. Typical early flowering plants include Adonia volgensis, Colchicum triphyllum, Gagea pusilla, Holosteum umbellatum, Hyacinthella leucophaea, Ornithagalum refractum, Paeonia tenuifolia, Veronica triphyllos and Viola suavis. But the flowering period reaches a peak in early summer when grasses such as Festuca rupicola and Stipa lessingiana come into flower together with species like Astragalus glaucus, Erysimum diffusum, Euphorbia nicaeenis, Minuartia viscosa and Ranunculus oxyspermus. The many endemic taxa found in these grasslands include Centaurea napulifera subsp. pseudoxillaris (Asteraceae), Linum dolomiticum (Linaceae), Ranunculus illyiricus (Ranunculaceae) and Seseli leucospermum (Apiaceae) and central European endemic Thymus pannonicus (Lamiaceae). Balkan Alpine Grassland High mountain grasslands are generally used as summer pasture and this together with past forest clearance has often extended these grasslands to lower altitudes than would normally be the case, and they may descend to as low as 1600 m. In general two types can be distinguished: those developed on predominantly alkaline soils on limestone and dolomite and those on acid or siliceous soils. The former is often dominated by the grass Sesleria nitida, Copyright © 2010 Peter Martin Rhind and may include many endemic species such as Aquilegia aurea (Ranunculaceae), Arabis ferdinandi-coburgi (Brassicaceae), Centaurea achtarovii, C. napulifera (Asteraceae), Cerastium decalvans (Caryophyllaceae), Edraianthus serbicus and Jasione bulgarica (Campanulaceae) and Veronica saturejoides (Scrophulariaceae). On acid soils Featuca, Poa, and Nardus stricta are usually the dominant taxa. These are less rich in endemic species but in Macedonia the endemic Knautia dinarica (Dipsacaceae) can be found in such grassland. Balkan Rock Vegetation In Bulgaria, Macedonia, Northern Greece and Serbia rock exposures are frequent in the hill and montane zones. This habitat is very rich in endemic species. In shady situations certain endemic Gesneriaceae including Haberlea rhodopensis, Jankaea heldreichii (Mt Olympus), Ramonda nathaliae and R. serbica are some of the more typical rock plants, although the latter is confined to limestone. These all have a rosette structures typical of many mountain plants. The plants normally associated with the more sunny exposures include endemics such as Euphorbia myrsinites (Euphorbiaceae), Inula ashersoniana and I. macedonica (Asteraceae) and Trachelium jacquinii (Campanulaceae). On limestone rocks in the Rhodope Mountains the assemblage of plants is likely to include endemics such as Dianthus petraeus (Caryophyllaceae), Linum rhodopensis (Linaceae), Scabiosa rhodopensis (Dipsacaceae), Linum dalmatica, Scrophularia aestivalis and Verbascum balcanicum (Scruphulariaceae). But throughout the BioProvince as a whole there are many other endemic species associated with rocky habitats including Achillea ageratifolium, A. clypeolata (Asteraceae), Aquilegia dinarica (Ranunculaceae), Amphoricarpus neumayeri, Campanula oreadum, C. waldsteiniana, Edraianthus dalmaticus, E. graminifolius and Jasione hedreichii (Campanulaceae), Centaurea macedonia (Asteraceae), Cerastium banaticum, C. decalvans, C. grandiflorum, Paronychia kapela (Caryophyllaceae), Globularia cordifolia (Globulariaceae), Haplophyllum balcanicum (Rutaceae), Iberis sempervirens (Brassicaceae), Lilium rhodopaeum (Liliaceae), Macrotomia densiflora, Moltkia doerfleri, Onosma thracica and Solenanthus stamineus (Boraginaceae), Marrubium velutinum (Lamiaceae), Morina persica (Dipsacaceae), Pinguicula balcanica (Lentibulariaceae), Polygala supina subsp. rhodopea (Polygalaceae), Primula kitaibeliana (Primulaceae), Saxifraga stribrnyi (Saxifragaceae), Sibirea altaiensis (Rosaceae), Sideritis scardica, Teucrium arduini and Thymus