Saffron (Crocus sativus L.) Cultivation Potential Zoning in Fars Province

Introduction: Increasing water scarcity and accelerating climate change have made the transition toward low-water-use, high-value crops essential for ensuring agricultural sustainability in Iran’s arid and semi-arid regions. Saffron (Crocus sativus L.) – with water requirements coincide with natural rainfall from autumn to early spring and a dormancy period throughout the hot, dry summer – represents a strategically valuable crop for these environments due to its drought tolerance and high economic return. Despite suitable ecological conditions, the cultivated saffron area in Fars Province during the 2024–2025 agricultural year was only 976.89 ha, with an average yield of 4.01 kg ha⁻¹ — well below the crop’s potential productivity. This situation reflects spatial mismatches between cultivated sites and areas of favorable ecological capacity. The main objective of this research was therefore to delineate saffron-suitable zones across Fars Province using a spatially explicit, multi-criteria framework integrating biophysical and infrastructural factors to inform targeted development policies. This study, for the first time in Fars Province, simultaneously evaluates climatic, physical, and accessibility–infrastructure criteria, while previous research in other provinces focused primarily on natural parameters.
 
Materials and Methods: The research employed a quantitative, descriptive–analytical design integrating the Analytic Hierarchy Process (AHP), Geographic Information System (GIS), and fuzzy logic. Twelve parameters were evaluated, grouped under three main categories: (1) Climatic: annual precipitation (optimal range: 200–400 mm), mean annual temperature (12–21 °C), and minimum (5–15 °C) and maximum (18–30 °C) temperatures; (2) Physical: elevation (1,000–2,500 m), slope (<10° for high suitability), aspect, soil texture (loam to silty loam), and land use; (3) Accessibility–Infrastructure: distances to road networks, population centers, and rivers. Weights were derived from pairwise comparisons conducted by 26 experts in agronomy, soil science, and urban–rural planning, all with at least five years of professional or academic experience in the province. Spatial datasets included a 30-m NASA DEM, long-term climatic records from 29 meteorological stations, land use maps from the Forests, Rangelands and Watershed Organization, and soil data from the Soil Grids global database. Layers were standardized using linear fuzzy membership functions and integrated via a weighted fuzzy overlay in GIS. The final zoning was classified into five suitability levels using the Natural Breaks (Jenks) method and validated against official saffron cultivation and production data for 2024–2025.
 
Results and Discussion: The results indicated that the climatic criteria exerted the highest influence (weight = 0.54), with annual precipitation identified as the most critical sub-criterion (sub-weight = 0.45), followed by mean annual temperature (0.26) and maximum temperature (0.17). Within the physical group (weight = 0.30), elevation (0.41) and slope (0.28) were the most decisive, while in the infrastructure group (weight = 0.16), the distance to road networks showed the highest importance (0.54). The consistency ratios for all comparison matrices were below 0.1, confirming logical expert judgments (average = 0.02). Spatial modeling revealed that 24.98% (30,538.71 km²) of the province is highly suitable, 30.98% (37,877.80 km²) suitable, and 23.93% moderately suitable, indicating that more than 55% of Fars Province has favorable ecological potential for saffron cultivation. Only 4.29% (5,246.02 km²) of the province was classified as unsuitable, corresponding mainly to hot southern counties (Lar, Lamerd, Khonj) and steep northern slopes (Izadkhast, Bavanat). Model validation confirmed a 96.70% spatial concordance between actual cultivated areas (944.7 ha out of 976.89 ha) and predicted suitable classes, as well as 96.74% conformity with total provincial production (3.80 t of 3.93 t), demonstrating strong predictive power and model reliability.
 
Conclusion: The integrated AHP–Fuzzy–GIS framework reveals that Fars Province possesses extensive but underutilized potential for sustainable saffron cultivation. The wide gap between potential (over 55% of provincial area) and current utilization (<1,000 ha) highlights the lack of spatially informed policy. The study’s zoning map provides a scientific basis for smart, evidence-based agricultural planning, including: (1) prioritizing governmental incentives (subsidies, credit facilities) for highly suitable and suitable zones; (2) improving moderately suitable areas through supplemental irrigation and soil management; (3) prohibiting saffron cultivation in unsuitable zones to prevent resource waste; and (4) developing a regional saffron value chain through local processing and branding (Fars Saffron). Although model accuracy was high, constraints such as the temporal resolution of climate data and expert subjectivity in weight assignment must be considered in policy implementation. Overall, this spatial decision-support framework contributes to improving water productivity, enhancing farmers’ incomes, and promoting sustainable rural economic development under ongoing water scarcity conditions.