Description
Location and General Description
This ecoregion lies in Turkey at the western end of the Eastern Anatolian Mountains. The high mountains provide refuges for the vegetation of different biogeographical realms that meet here, including: dry central Anatolian plateau; Arabian plateau, with its desert characteristics; the warm, humid Black Sea region, and continental east Anatolia plateau.
The main geographical units that make up this ecoregion are the Upper Euphrates River, the Anti Taurus Mountains and the western part of the Eastern Anatolian Mountains. The Tahtal? Mountains delineate the ecoregion’s western boundary, while the arc of the Anti Taurus Mountains between the Euphrates and Tigris rivers determines its southern boundary. The eastern and northern boundaries of the ecoregion are less apparent since the mountainous nature of eastern Anatolia continues beyond the ecoregion boundaries. However, to the north, the gradually decreasing influence of the humid-warm Black Sea climate distinguishes this region from its northern neighbor. In the east, the increasing effect of the continental climate and the greater height of the plateaus are the principal factors separating this region from the adjacent region of montane steppe.
The Anti Taurus ridge encompasses the higher points of the ecoregion, including the Tahtal? Mountains, Nurihak Mountain (2,548 m), Malatya Mountain (2,583 m), and Munzur Mountain (3,462 m). The Upper Euphrates high plateau lies east of the Anti Taurus and Munzur Mountains at between 800 and 1,500 m. The Ceyhan, Tigris and Euphrates rivers are most the important rivers of Anatolia; all have their upper catchment basins in this ecoregion. Hazar Lake and Nemrut Crater Lake are the principal natural water bodies here, and a number of artificial reservoirs have been created by the network of dams along the larger rivers.
The ecoregion has a continental climate with extreme winter temperatures and heavy snowfalls. Annual precipitation varies between 600 and 1,000 mm.
Some Mediterranean elements can be found in the Anti Taurus Mountains. However, as one moves inland, Kurdo-Zagrosian steppe forest vegetation becomes dominant (Boulos et al. 1994). Oak dominates the steppe forests here, with the most important species including: Quercus brantii, Q. libani, Q. boissieri, and Q. ithaburensis ssp. macrolepis. Since the area is characterized by a dry continental climate, these forests are resistant to cold temperatures and water shortages and are therefore considered dry or xeric forests (Atalay 1994). The principal arboreal communities of the ecoregion include: Quercus robur ssp. pedunculiflora forest (Zohary 1973), Pinus sylvestris montane forest, wild orchards of Rosaceae species, Rosa pimpinellifolia-Rosa canina shrublands (Mayer & Aksoy 1986), Platanus orientalis valley forest (Mayer & Aksoy 1986), humid relict Euxinic forests of Alnus spp-Castenea sativa-Acer spp.-Lonicera caucasica (Yalt?r?k 1973), and Juniperus communis ssp. nana-Convolvulus calvertii woodlands. An open canopy, well-developed grass layer and a patchy distribution resulting from human exploitation characterizes these forests.
Although there are some natural steppe formations, the area they cover has extended well beyond their natural occurrence as forests have been destroyed or degraded. The principal steppe communities include: Artemisia fragrans steppe, most common at lower elevations; tragacanthic steppes of Astragalus spp., Gundelia tournefortii, Noaea mucronata, Thymus spp., and Salvia cryptantha – often in oak forest clearings (Boulos et al. 1994); various graminoid formations (Zohary 1973, Çetik & Tatl? 1975); and high mountain steppes of Achillea vermicularis, Ajuga chia, Helianthemum nummularium, Malcolmia africana, and Marrubium parviflorum (Boulos et al.1994).
Biodiversity Features
One of the most distinctive biodiversity features in this ecoregion is known as the Anatolian Diagonal, a remarkable floristic line crossing inner Anatolia. So named by Davis (1965, 1971), the Anatolian Diagonal runs from the southern foothills of the Black Sea Mountains around Bayburt, through the Munzur Mountains and the Anti Taurus range, and then splits into two branches; one branch reaches the Mediterranean via the Amanus Mountain and the other via the Bolkar Mountain (Davis 1971). Approximately 390 plant species have distributions largely confined to the Anatolian Diagonal, including the monotypic genus Neotchihatchewia (N. isatidea) and Graellsia davisiana. Many of Turkey’s other plant species occur only to the west or only to the east of this line (Ekim & Güner 1986). The origin of this Diagonal is a point of discussion; Davis (1971) and Sonnenfeld (1974) emphasize paleogeographical factors while Ekim & Güner (1986) attribute greater importance to ecological and climatic factors (Boulos et al. 1994).
This region is considered one of the most important areas of plant biodiversity in Turkey (Ekim & Güner 1986, Ekim 1987, Boulos et al. 1994). Approximately 3,200 vascular plant species are found here, 725 of which are endemic to Turkey; 82 species are endemic to the Anti Taurus Mountains and about 165 species are endemic to the Upper Euphrates region (Boulos et al. 1994). The Munzur and Anti Taurus Mountains, the Elbistan-Darende region, Kemaliye, Ke?i? Mountain, Harput and Hazar Lake are all recognized as biodiversity centers.
This region is home to several species classified by the IUCN as vulnerable, such as the otter (Lutra lutra) and wild goat (Capra aegagrus) (IUCN 2001). Other important mammals live here, such as the lynx (Felis lynx), bear (Ursus arctos), wolf (Canis lupus), red fox (Vulpes vulpes), boar (Sus scrofa), and ibex (Capra ibex). Trout (Salmo trutta) swim in the Munzur and Mercan rivers. Birds include chukar (Alectoris chukar), partridge (Perdix perdix) and eagles (Aquila spp.)(WCMC-UNEP 1988).
Current Status
The land in this ecoregion lies along historic east-west travel routes and has a long history of human settlement. Thus, although it is mountainous and characterized by the high plateaus and rugged landscape, much of the forest has been destroyed by long periods of human use. More than half of the forest around Bingöl has been cleared within the last 20 years (Atalay 1994), and the composition of the steppe vegetation has been altered.
There is only one protected area in the ecoregion. The Munzur Valley National Park covers 48,000 ha and lies in one of the area’s centers of endemism. The park is important in terms of plant biodiversity and rich in wildlife.
Types and Severity of Threats
Overgrazing is a problem here, and forests have been cut extensively for fodder, construction materials and fuelwood. Large-scale reforestation schemes intended to produce wood for fuel and other purposes completely alter or destroy natural vegetation communities. In addition, dam construction and large-scale irrigation schemes along the Tigris and Euphrates rivers pose significant threats to the native plant species either by flooding their habitat or altering the water regimes to which they are adapted (Boulos et al. 1994).
Justification of Ecoregion Delineation
This ecoregion lies at the boundary of two bioregional systems. It includes the deciduous and mixed forests and some deciduous tree steppes of Eastern Anatolia as delineated by Guidotti et al. (1986). In addition, the eastern boundary is a rough approximation of the transition into the Eastern Anatolian montane steppe ecoregion, based on the ‘mosaics of NW Iranian Artemisietea fragrantis high steppe and Quercetea brantii remnants’ identified by Zohary (1973).
References
Atalay, ?. 1994. Türkiye Vejetasyon Co?rafyas?. Ege Üniversitesi Bas?mevi. ?zmir, Turkey.
Boulos L., A. G. Miller, and R. R. Mill. 1994. South West Asia and the Middle East. Pages 293-349 in S. D. Davis, V. H. Heywood, and A. C. Hamilton, editors. Centres of Plant Diversity. Information Press, Oxford.
Çetik, R. and A. Tatl?. 1975. A phytosociological and ecological study on the vegetation of Palandöken mountain. Comm. Fac. Sci. Univ. of Ankara 19/C, Ankara, Turkey.
Davis, P.H., editor. 1965-1985. Flora of Turkey and the east Aegean islands. Vol.1-9, Edinburg University Press, Edinburgh, Great Britain.
Davis, P. 1971. Distribution patterns in Anatolia with particular reference to endemism. In Davis Harper and Hedge, editors. Plant life of South-West Asia. Bot. Socie. of Edinburgh, Great Britain.
Ekim, T., and A. Güner. 1986. The Anatolian Diagonal: fact or fiction. In I.C. Hedge, editor. Plant life of South-West Asia. Bot. Socie. of Edinburgh, Great Britain.
Ekim, T. 1987. Plants. In A. Kence, editor. Biological diversity in Turkey. Environmental Problems Foundation of Turkey, Ankara, Turkey.
Guidotti, G., P. Regato, and S. Jimenez-Caballero. 1986. The major forest types in the Mediterranean. World Wildlife Fund, Rome, Italy.
IUCN. 2001. The 2000 IUCN Red List of Threatened Species. IUCN, Gland, Switzerland and Cambridge, United Kingdom.
Mayer H. and H. Aksoy. 1986. Walder der Türkei. Gustav Fischer Verlag, Sttutgart, Germany.
Sonnenfeld, P. 1974. The Upper Miocene evaporite basins in the Mediterranean region – a study in paleo-oceonography. Geol.Rundschen 63:1133-1172.
UNEP-WCMC. 1988. "Munzur Valdisi NP (Munzur Valley)" page in Protected Areas Database on WCMC-UNEP web site:
http://www.unep-wcmc.org/protected_areas/data/sample/0072v.htm
Yalt?r?k, F. 1973. The floristic composition of major forests in Turkey. ?.Ü. Orman Fakültesi Yay?nlar?. 1921/209.
Zohary, M. 1973. Geobotanical Foundations of the Middle East. 2 Bde. Gusatv Fischer Verlag. Stuttgart, Germany.
Prepared by: Ugur Zeydlani
Reviewed by: In process