Identification of Groundwater Potential Zones Using GIS and Fuzzy-AHP in Arid and Semi-Arid Regions: A Case Study of Nayband, Iran

Abstract

Groundwater represents a primary source of water supply in arid and semi-arid regions where surface water availability is severely limited. Increasing demand driven by rapid population growth, agricultural expansion, and industrial development requires robust and cost-effective assessment strategies for groundwater resource planning. This study delineates groundwater potential zones in the Nayband Plain, Tabas County, eastern Iran. The analysis integrates Geographic Information Systems (GIS) with the fuzzy Analytical Hierarchy Process (Fuzzy-AHP). Seven hydro-environmental factors—slope, geomorphology, soil texture, lineament density, land cover, precipitation, and proximity to drainage networks—were selected and weighted based on expert knowledge within a fuzzy multi-criteria decision-making framework. The resulting groundwater potential map was classified into five categories: very good, good, moderate, poor, and very poor. Findings indicate that approximately 36% of the region exhibits good to very good groundwater potential, predominantly in the northern and northwestern sectors of the plain. Model validation using 10 wells, 3 qanats, and 3 springs demonstrated a strong spatial agreement between high-potential zones and existing groundwater extraction structures. The results confirm that coupling GIS with fuzzy-AHP provides a reliable and transferable methodology for groundwater resource evaluation, especially in data-scarce arid regions. This approach supports informed decision-making for sustainable groundwater exploitation and artificial recharge projects in environments with high water scarcity.