Identification and evaluation of medicinal plants diversity in mountain rangelands of Anbaran, Ardabil province

Knowing medicinal plants, measuring structural features and their species diversity indices are of the essential requirements to determine the suitability of rangelands for the use of medicinal plants. In this regard, the research was carried out in the mountain rangelands of Anbaran. For this purpose, vegetation cover was measured using 320 plots of one square meter, with a distance of 10 meters from each other along 100-meter transects in 16 vegetation types, and the values of species diversity indices in different elevation classes and aspects were calculated. Based on the results, 16 medicinal species are distributed in the plant composition, with a relative importance varying from 0.9 to 59. The highest relative importance is related to Verbascum erianthum, Cynodon dactylon and Acroptilon repens, and the least belongs to Papaver acrochaetum, Hyoscyamus arachnoideus, Iris falcifolia, Allium scabriscapum and Matricaria chamomilla.The results showed that the values of the Shannon–Winear  in the altitudes of 1750-1500 meters and 1750-200 meters were 0.569 and 0.651, respectively, showing no significant difference with each other. The value of the index in the northern and southern directions is equal to 0.691 and 0.511, and the northern aspects are more favorable than the southern ones. Therefore, with regard to the range of Shannon–Winear index (0-4.5), it seems that the rangelands are not desirable for the species diversity of medicinal plants, which is necessary to increase species diversity with direct management. The findings of this study can be used to locate medicinal plants in order to protect, exploit, seed production and provide part of the livestock holder’s income.