| Abstract:
A large part of rangelands in our country is located in arid and semi-arid regions. In this climate, the variability of vegetation is affected by changes in the energy flux in rangeland ecosystems and usually occurs in the composition and structure of vegetation over time. On the other hand, human factors and especially rangeland management have an influential role in maintaining rangeland stability or degradation. Accordingly, the monitoring of vegetation cover was carried out in winter rangelands of Ardebil province during 2008 to 2012. At first, using the available resources, the major habitats of the area were determined and then in each habitat a key area was selected for statistical analysis. Then, in each key area, canopy cover, density, and frequency were measured along three transects of 500 m within 30 plots of 1. 20*1. 20 m. Soil moisture and organic carbon were also measured. The results showed that, during a four-year period, shrub species had the main role in vegetation changes depending on the changes in rainfall and temperature. In the Moghan site, Artemisia fragrans was identified as the key species in vegetation changes due to the absolute dominance, high regeneration and direct response to seasonal and annual rainfall. Changes in soil cover were a function of changes in total canopy cover due to the relative stability of stone, gravel and litter cover. The results of studying the changes in vegetation, climate and soil moisture as well as soil erosion condition could be a good guide to correct the current management methods of these rangeland ecosystems.
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