AHP-based Climatic Zoning for Saffron Cultivation in the Water-deficient Kerman Province

Saffron (Crocus sativus L) is an expensive and highly valuable plant recognized globally for its many medicinal properties and low water demand. Hence, the development of saffron farms in semiarid regions has received much attention as it increases water use efficiency (WUE) in such water-deficient areas. Considering the different factors involved in saffron growth and yield, the geographical information system (GIS) is the best and most cost-effective method to identify areas potentially favorable to saffron cultivation. The current study aimed at zoning the land area favorable to saffron cultivation in Kerman Province was conducted over the period 2017-2019. The required daily data were collected from 13 synoptic stations recorded during the years 1998 to 2016, which were subjected to the homogeneity test before the relevant GIS information layers including altitude, slope, frost, rainfall, absolute maximum and minimum temperatures, and probability of temperatures below 5º Celsius in November were prepared. Subsequently, the relevant variograms were drawn. Also, the slope map was extracted using the digital elevation model. Finally, weights were assigned to the above layers using the Analytical Hierarchy Process (AHP) technique, and the final zoning map was prepared in ArcMap. The map thus prepared revealed that the southern and eastern stretches of the province were not suitable for saffron cultivation while the more favorable areas were located at the foothills in Baft, Bardsir, Zarand, and Shahrbabak towns. Moreover, Kahnuj, Manojan, southern parts of Jiroft, eastern stretches of Bam, and southern stretches of Baft, accounting for around 59% of the total provincial land area, were recognized as unfavorable to saffron cultivation. The remaining lands of the total provincial area were classified as follows: 15% relatively suitable, 16% suitable, and about 10% highly suitable for saffron cultivation.