Assessment Rangelands Drought Vulnerability in Arid and semi-arid regions(Case Study: Pishkouh Watershed, Yazd Province)

Drought can reduce the sustainable production of natural ecosystems, including rangelands. The main purpose of this study was to expand the vulnerability of rangelands drought in the Pishkuh watershed in Yazd province. In the present study, geographical information systems and multi-criteria decision-making method (AHP) were used. In this regard, the parameters affecting the drought vulnerability of rangelands of the study area, including slope, slope direction, precipitation, soil texture, and evaporation were extracted and converted into information layers with the help of GIS. After weighing the layers in terms of importance in drought vulnerability in the framework of multi-criteria decision making (MCDM), the final combination and drought vulnerability map of the study area was prepared. Also, to control and measure the final map, field studies of the study area were used. Finally, a map of the dominant rangeland vegetation type was prepared and overlapped with the drought vulnerability map of the rangelands of the study area to identify the most resistant and vulnerable rangeland vegetation type. The results showed that the highest weight of the effective parameters in rangeland drought vulnerability was related to the precipitation with a value of 0.54, and the lowest weight was related to the slope with a value of 0.061. Based on the results, the eastern, southeastern, and southern regions of the Pishkuh watershed have the highest rate of rangelands drought vulnerability, and Ar.au-St.ba.Sc.or type is the most vulnerable vegetation type in the study area. It is recommended that more management resources and strategies be implemented in vulnerable rangelands to protect the soil and its vegetation.