Comparative Evaluation of Fuzzy Overlay Models for Identifying Potential Sites for Tourist Accommodation in Dezpart Region Using Gamma and Sum Models

Tourism as a vital economic sector necessitates infrastructure development. Within this context, provision of tourist accommodation stands out as a crucial service for sectoral growth, requiring optimal siting based on diverse regional indicators and capacities.

This study aimed to identify potential areas for establishing tourist accommodation in Dezpart Region in Khuzestan Province. Additionally, it conducted a comparative analysis of fuzzy overlay models to assess their respective outcomes.

The research employed a descriptive-analytical approach based on spatial data. Fuzzy logic analysis was conducted using ArcGIS software, involving data standardization, fuzzification using established algorithms, and application of the Analytic Hierarchy Process (AHP) model to derive criteria weights. The fuzzy overlay methods were then utilized to generate the final map.

The results indicated that, among the 9 criteria examined, the distance from tourism sources (with a final weight of 0.290) and the distance from fault lines (with a weight of 0.192) were the most influential in identifying areas suitable for tourist accommodation. Furthermore, analysis of the fuzzy overlay models confirmed that the Gamma model was more stringent and pessimistic compared to the Sum model. According to the Sum fuzzy model, over 39.41% of the area was deemed suitable, whereas the Gamma model identified only 10.3% as suitable for accommodating tourism services. The overall quality assessment also supported the superiority of the Sum model in delineating potential areas for tourist accommodation. Examination of the spatial distribution of the final maps revealed a greater concentration of suitable areas in the central and northern regions.

Establishment of tourist accommodation facilities at the regional level is an indisputably significant matter. However, determining the optimal siting of these services necessitates the utilization of various methods and amalgamation of diverse criteria, a task well-suited for the capabilities of a Geographic Information System (GIS) environment. Dezpart Region in Khuzestan Province, which was designated as a new city in 1401, possessed multifaceted potential for tourism development, alongside its agricultural sector. The region boasts a rich array of tourism resources and attractions, encompassing historical, natural, rural, and cultural elements and thus underscoring the imperative for strategic planning in this area. A pivotal aspect of this planning involves identifying the most suitable locations for establishing tourist accommodation centers. This endeavor not only contributes to the fundamental advancement of tourism, but also aids in attracting tourists over the medium and long terms. Consequently, this research aimed to identify potential areas for establishing tourist accommodation in Dezpart Region in Khuzestan Province, while also conducting a comparative assessment of fuzzy overlay models to discern the most effective approach. 

The research methodology employed in this study was descriptive-analytical and practical in nature. Data collection and analysis were conducted using documentary and organizational methods. The primary data utilized for map preparation consisted of the spatial data obtained from the country's mapping organization. To process the spatial data, operations, such as equalization, data formatting, ground referencing, and data adaptation, were performed. The criteria considered in this research encompassed elevation, slope, land use, distance from communication roads, distance from urban and rural settlements, proximity to tourism attractions, proximity to water sources (rivers), and distance from fault lines. Subsequently, the data underwent standardization and fuzzy logic analysis within the ArcGIS software. Weighting the criteria was done by using Expert Choice software and the Analytic Hierarchy Process (AHP) method. Consequently, the weights of the influential criteria for locating tourist accommodation centers were established. Finally, employing various fuzzy models or operators, including Gamma and Sum, a map was generated to identify potential areas for establishing accommodation-tourism centers. 

In this study, the criteria of distance from communication roads, rural and urban settlements, and proximity to tourism sources were assigned a value and membership of 1 for locations with shorter distances. This was because, for instance, closer proximity to communication roads or tourism resources signified greater suitability for accommodation-tourism services, making closer areas more pertinent for the research objective. A linear function was employed to fuzzify the map for these criteria.Utilizing the Gaussian function, a threshold limit was established such that any deviation beyond this threshold, whether an increase or decrease, would result in a value of zero for the areas or locations. For instance, a threshold limit of 3 km was set to assess the distance from water sources with values approaching zero for deviations from this threshold.Additionally, a small function was utilized to fuzzify the elevation and slope criteria with respective threshold limits of 1700 m and 25%. Consequently, areas with lower slope or elevation were assigned a membership grade of 1. Conversely, a large function was employed to fuzzify the distance from fault lines (with a threshold limit of 10 km) and land use (with a threshold limit of 4), resulting in areas with greater distance or value being assigned a membership grade of 1, thus denoting their suitability.The results revealed that among the 9 criteria examined, the distance from tourism sources (with a final weight of 0.290) and the distance from fault lines (with a weight of 0.192) were the most influential in identifying areas suitable for accommodation-tourism services. A comparison of the proposed maps indicated that the Sum overlay method identified more potential areas for accommodation-tourism services in the region compared to the Gamma method. Furthermore, the Sum method encompassed the central, western, and eastern areas, while the Gamma method suggested a narrow line in the central area for tourist accommodation. Notably, the proposed area deemed highly suitable for creating accommodation-tourism places covering 39.27 km2, which was equivalent to over 3.10% of the region's area, in the Gamma overlay method. In contrast, the Sum method identified 499.72 km2, representing 39.41% of the region's area as highly suitable for accommodation-tourism services. 

Analyses of the fuzzy overlay models revealed that the Gamma model was more stringent and pessimistic compared to the Sum model. According to the Sum fuzzy model, over 39.41% of the area was deemed suitable for creating accommodation-tourism services, whereas the Gamma model identified only 10.3% as suitable. The overall quality assessment also confirmed the superiority of the Sum model in delineating potential areas for accommodation-tourism services. Examination of the spatial distribution of the final maps further indicated that the susceptible areas were more prevalent in the central and northern geographical regions.