Location and General Description
The Elburz Range Forest Steppe ecoregion occupies the southern and eastern slopes of the Elburz Mountain range in northern Iran. The mountains extend approximately 1,000 km (600 miles) in an arc from Astara (at the edge of the Azarbaijan region) along the southwestern and southern coasts of the Caspian Sea and into the northeast reaches of the country as far as Jajarm.
The ecoregion is bounded to the north by the Caspian Hyrcanian Mixed Forest ecoregion that occupies the northern and western slopes of the Elburz range and the southern Caspian coastal plain. To the northwest, it runs into the Talish-Azerbaijan mountains, and to the south, it faces Iran’s central plateau. To the east, it runs nearly to the border with Turkmenistan and then extends southeast for a distance of about 250 km (160 miles); it then hooks back again in to the northwest for approximately another 140 km (90 miles).
Elevation generally ranges from 2,000m to 4,000m, with some peaks exceeding 5,000m; Mount Damavand, a dormant volcano, is the highest peak at 5,671m. The mountains are composed of limestones, shales, sandstones and tuffs, including 3,000m tuff beds on the southern slopes. Metamorphic and pre-eruptive rock are widespread, with schists, marbles, amphybolite and granitic rocks in the central Elburz (UNEP 1989a).
Facing Iran’s arid central plateau region, the ecoregion receives only 150 to 300 mm of precipitation annually (Anderson 1999), mostly in the winter. The mean annual temperature ranges from 15-18 degrees C, with extreme winter temperatures. Juniper (Juniperus polycarpos) forest once covered the southern slopes of the Elburz Mountains, as evidenced by numerous remnants, and could be found up to altitudes of 1,900m to 2,000m (Zohary 1973). There is also evidence that the juniper forest steppe in Iran once occupied not only larger extents of the Elburz-Khurasan mountains but also much of the territory to the south, including some of the higher ranges and peaks in the Central Plateau (Zohary 1973).
The typical shrub story in the juniper steppe forests of this area may include pistachio (Pistacia atlantica), cotoneaster (Cotoneaster racemiflora), Crataegus spp., maple (Acer turcomanicum), almond (Amygdalus spp.), and other species. The groundcover commonly includes communities of Artemisietea herbae-albae iranica or the tragacanthic (thorn-cushion) Astragaletea iranica.
In more recent times, however, the vegetation has been heavily disturbed, and juniper forest tends to be restricted to the higher altitudes of the southern slopes. The lower slopes now reportedly support a zone of Pistacia atlantica, while Artemisia, Cousinia, and other genera are now more common in the degraded areas (Breckle 1983).
The montane steppe supports a large population of wild sheep (Ovis ammon), and goitered gazelle (Gazella subgutturosa) are found on the plains in the southeast. These and other prey species sustain leopard (Panthera pardus), jungle cat (Felis chaus), wolf (Canis lupus), jackal (Canis aureus) and red fox (Vulpes vulpes). Other species include brown bear (Ursus arctos), stone marten (Martes foina), wild boar (Sus scrofa), red deer (Cervus elaphus) and roe deer (Capreolus capreolus) (UNEP 1989a; UNEP 1989b). The antlers of Cervus elaphus have long been sought by trophy hunters and for the creation of knife and dagger handles; Cervus elaphus is also valued for its venison (Humphreys & Karom 1995).
The lesser spotted eagle (Aquila pomarina) and the golden eagle (A. chrysaetos) breed in the forested hills and mountain areas in this ecoregion (Humphreys & Kahrom, 1995). At least 151 species of avifauna have been recorded in the Golestan Biosphere Reserve, including most notably the honey buzzard (Pernis aviporus), goshawk (Accipiter gentilis), black vulture (Aegypius monachus), bimaculated lark (Melanocorypha bimaculata) and Caspian snowcock (Tetraogallus caspius). The site is also one of the few breeding areas in Iran for little bustard (Tetrax tetrax) and woodpecker (Dryocopus martius) (UNEP 1989b).Certain taxa of lizards occur on the southern slopes of the Elburz Mountain range where winter and spring precipitation exceeds 200 mm annually; these include Laudakia caucasia, Trapelus ruderatus, and others (Anderson 1999).
This area has suffered a significant reduction in natural vegetation. Juniperus polycarpos forest, which once covered the southern slopes of the Elburz Mountains, exists now largely in scattered remnants and at higher altitudes in relatively inaccessible areas (Zohary 1973). Although J. polycarpos is resistant to drought, heat and cold, it is a slow-growing tree and therefore juniper forests are difficult to re-establish once cut.
The loss of vegetation on the sloped areas commonly results in soil erosion and an overall reduction in vegetation coverage, as well as in changes to the vegetation composition. Thorny shrubs, dwarf-shrubs and thorn-cushions increasingly dominate plant communities as species that can better withstand grazing and pruning gain a selection advantage (Frey & Probst 1986).
The Golestan National Park and the adjacent Ghorkhod Protected Area, both designated as a Biosphere Reserve in 1976, lie on the mountainous divide between the Caspian and the arid interior region, at the easternmost tip of the Elburz Range. Covering an area of about 125,895 ha, the reserve ranges in altitude from 380m to 2,410m and is home to many mammals, avifauna and reptiles (UNEP 1989).
Types and Severity of Threats
Overharvesting of fuelwood and overgrazing are among the primary factors behind the degradation of the natural vegetation and the soils in this ecoregion (Frey & Probst 1986).
Justification of Ecoregion Delineation
This ecoregion boundary was determined using Zohary’s (1973) geobotanical map of the Middle East and corresponds to the Juniperus polycarpos steppe forest remnants within the Iranian steppe forest climax zone.
Anderson, S.C. 1999. The lizards of Iran. Society for the Study of Amphibians and Reptiles. St. Louis, Missouri, USA.
Breckle, S.W. 1983. Temperate deserts and semi-deserts of Afghanistan and Iran. Pages 271-316 in N.E. West, editor. Ecosystems of the World 5: Temperate Deserts and Semi-Deserts. Elsevier Scientific Publishing Company, New York.
Frey, W., and W. Probst. 1986. A synopsis of the vegetation in Iran. Pages 9-43 in H. Kurschner, editor. Contribution to the vegetation of Southwest Asia.
Humphreys, P.N. and E. Kahrom. 1995. The lion and the gazelle. Comma International Biological Systems, Gwent, United Kingdom.
UNEP-WCMC. 1989a. Islamic Republic of Iran: Alborz-e-Markazy and Karaj Protected Areas. Protected Areas Database on UNEP-WCMC web pages (http://www.unep-wcmc.org/protected_areas/data/sample/1653v.htm), visited on October 24, 2001
UNEP-WCMC. 1989b. Islamic Republic of Iran: Golestan Biosphere Reserve, National Park … and the adjacent Ghorkhod Protected Area. Protected Areas Database on UNEP-WCMC web site (http://www.unep-wcmc.org/protected_areas/data/sample/0372v.htm), visited October 24, 2001.
Zohary, M. 1973. Geobotanical foundations of the Middle East: Vol.1, Gustav Fischer Verlag, Stuttgart, Germany.
Prepared by: Julie Bourns
Reviewed by: In process