The spatial assessment of suitable areas for medicinal species of Astragalus (Astragalus hypsogeton Bunge) using the Analytic Hierarchy Process (AHP) and Geographic Information System (GIS)

Abstract

Climatic variation and different ecological conditions is led to the species diversity and richness of medicinal plants throughout the country. In this study, the effective criteria were identified in determining suitable areas for the Astragalus; including the six main criteria of precipitation, temperature, slope, altitude, soil texture and orientation, based on the purpose of the study and regional characteristics, field surveys, local information and expertise opinions. The Analytic Hierarchy Process (AHP), Pair comparison method and expert choice “11” software were used to determine the incompatibility rate of the criteria based on the questionnaire. The basic researches and integration of informative layers were done using GIS. Therefore, suitable areas were obtained for Astragalus hypsogeton Bunge in the Bahar Mountains catchment, using overlaying of maps. The results showed that the class of more than 2400 m height with relative importance of 0.5172 and 2100–2400 m, and the relative importance of 0.2702 are located on the first and second priority to locate Astragalus hypsogeton Bunge in Bahar Mountain catchment. Furthermore, the tree main criteria of altitude, precipitation and temperature have been allocated the most relative importance of 0.33, 0.22 and 0.16, respectively and located on the top three priorities. 1354.3 ha of the total area of Bahar Mountain catchment was identified as a suitable area for Astragalus hypsogeton Bunge. The study could ultimately show that it can be obtained an optimal locality to identify medicinal plants in different areas using modern technology, GIS and AHP with minimal cost and time. Keywords: Spatial assessment, Astragalus hypsogeton Bunge, Geographic Information System (GIS), Bahar Mountain catchment