معرفي جامعه هاي گياهي شمال بخش امن منطقه حفاظت شده مياندشت در استان خراسان شمالي

Introduction of plant associations of the safe part of Miandasht protected region in North Khorassan province

Miandasht protected region with 84435 hectars of land, and mean annual precipitation of about to 250 mm is located 10 kilometers from East of Jajarm in West of North Khorassan province. Based on climatic classifications, this area is arid. Field exploration was performed from 2004 to 2008.Eco-phytosociological method was used in the present study. In this method, in addition to physionomical and floristically criterions, ecological criterions are also important for determining the endogen environments. Ecological factors including altitude, slope degree, exposition and soilʹs pH, EC, OC and texture were measured in all releves. Finally the ecological conditions of all identified syntaxa were determined. Phytosociological data were analyzed by Factorial Correspondence Analysis and Hierarchical ascendant Classification methods, using anaphyto software. Analysis of the data of 196 species and 195 releves resulted in distinguishing 33 associations and 2 sub-associations. Based on distribution area in the region, the most important associations were Ephedretum sarcocarpae, Artem isietum sieberi, Caricetum physodis, Halimocnemidetum piliferae and Stipagrostisetum plumosae