climatological capability of saffron cultivation in kermanshah and kurdistan provinces

one of the most famous horticultural exporting products of iran is saffron. at present, the main region for the production of saffron is the northeast region of iran (khorasan-e razavi and southern khorasan provinces). the present research intends to survey the suitable areas for cultivation of saffron in the west of iran (kermanshah and kurdistan provinces) which, in the climatic conditions, is very similar to the east of country. on this basis, the climatic data effecting saffron growth, including precipitation, temperature, relative humidity, sunshine hours and number of frost days, have been gathered for 11 stations during 3 growth phases (generative phase, vegetative phase and dormancy phase) and compared with a new base table to determine the suitability of climatic conditions for planting of the product in each growth phase for each variable. then according to the rate-weighting method, the importance degree or weight of each climatic variable in every growth phase was determined. in the next step, saffron planting appropriateness maps were prepared in the raster method using gis, considering importance degree or weight of each variable in each phase. then, through adding the pixel values in the three growth phases, the appropriateness map for each variable was identified (totally 11 maps), and via averaging the pixel values in these 11 maps the compiled map of appropriateness of variables was determined as well. finally the last appropriateness map for saffron cultivation was prepared taking into account the appropriate slope and elevation domains in the recent map. the results showed that around 30.48 percent of the region area (16500 km2), which covers mostly kermanshah’s western, ravansar’s southern and qorveh’s plains, has a fair potentiality for saffron cultivation. the remainder area of the region including 37600 km2 (69.48 percent of the region area) has no potentiality for cultivating of this product