Siahkuh protected area is managed by the Dept. Environment of Yazd province since 2001.This region (199512 ha) contains a flat plain covering about (65%) with altitude 950-2050m. A study was conducted to determine vegetation and wildlife biota as well as limiting factors. Major limiting factors are : climatic limits(precipitation equal 48 mm/year), length of aridity season, land resources limitations salinity, high ground water table, soil depth inaducey, erosion and sedimentation , land drainage problem) and lack of water resources. Other factors are mine exploitation and hunting. In this harsh ecological conditions, xerophytes vegetation and aridity resistance wildlife are living.47 species of plants belong to 43 genera and 25 families were identified . Major plant families are Chenopodiaceae with 9 taxa, Compositae and Umbelifera with 4 taxa, and Polygonaceae with 3 taxa. Based on Red Data List 4 taxa in Lower Risk(LR) includ:Hyssopus angustifolius, Zataria multiflora, Salsola yazdiani and Acantholimon scorpus.Later two taxa are endemic.
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