Land suitability assessment for cumin production in North, Razavi and South Khorasan provinces using Geographical Information System and modeling approach

Land evaluation and its consistency with simulation model’s outputs could assist decision making to develop plants for cultivation. In this study land suitability and potential yield of cumin was determined using CUMMOD and sum of values method by climatic and topographic factors, respectively, as a case study in Khorasans provinces. Results revealed that despite of the majority of favorable and completely favorable zones, potential yield was not the same in studied provinces. The CUMMOD results revealed that southern, a part of central and a part of northern areas of northern Khorasan province have considerable capability to produce cumin (2.5 to 3 ton ha-1). Potential yield was in two classified ranges as 2- 2.5 ton ha-1 and < 2 ton ha-1, while, predicted potential yield for central and southern parts of South Khorasan province was <2 ton ha-1 and 2-2.5 ton ha-1 for corresponding northern parts. Slope and aspect for northern, aspect and maximum temperature for Razavi and maximum temperature for southern Khorasan were the most limiting factors. In this study, although limiting factors were detected, but the majority of zones were located in favorable and completely favorable zones, because sum of values method avoids exaggerated effects of some factors. Therefore, results are more realistic. Overall, our results confirmed that the potential yield will decrease along with moving from northern Khorasan province toward South Khorasan province, which stems from shortening of the growing season.