Extended Abstract

Introduction

The optimal spatial distribution of urban green spaces is a must for achieving sustainable development and ensuring equitable access to municipal services. Accordingly, this study tried to focus on evaluating the optimal location for urban green spaces of the city of Zabol using the minimum standards. The main objective of this study was to determine the optimal location for intra-urban green spaces to achieve a proportional distribution of this kind of land use, and finally facilitate the accessibility and enhance the fulfillment of demands. The current urban green spaces of Zabol lack balance and commensurate distribution across its various municipal districts and neighborhoods. Consequently, this study endeavored to provide a more systematic organization for this category of urban space by performing optimal location selection in Zabol, utilizing contemporary meta-heuristic algorithm integrated with Geographic Information Systems (GIS). The main research question was: How can the optimal location for the urban green spaces of Zabol be determined through the implementation of the Tabu Search (TS) meta-heuristic algorithm?
 

Method

This applied study used a descriptive-analytical method grounded in documentary and field studies and was conducted in the city of Zabol. The required data were collected from relevant organizations, comprehensive urban plans, existing maps, records, and statistical reports. The variables entailed data related to green spaces, residential areas, transportation networks, per capita provision, access distances, and other pertinent factors. The data were analyzed using the ArcGIS, Super Decision, and MATLAB software. Information layers detailing the current urban land uses and the spatial distribution of green spaces of Zabol were used to identify locations for new green spaces. The ai was to increase both the per capita area and the total extent of this kind of land use. Finally, the tabu search meta-heuristic algorithm was employed in the context 
of solving a hub location problem to select the final optimal zones within the city of Zabol.
 

Results

The findings of this study are multifaceted since we used diverse methods and analytical techniques. The study scrutinized the factors influencing the locating of urban green spaces cosidering various dimensions, including physico-spatial and socio-cultural dimensions. The two most critical determinants in the spatial allocation of land uses are distance and time. The nature of accessibility is usually measured by the two components, which collectively serve as the primary metrics for evaluating comfort (or amenity). The ease of access to essential urban services for people and the requisite separation from disruptive or incompatible land uses are considered vital components of urban comfort. Accordingly, the data layers were weighted and evaluated based on a distance criterion of 100 meters. This study focused on analyzing the following locational indicators for the optimal locating of green space: proximity to existing land use indicators, proximity to fallow lands, proximity to educational centers, proximity to cultural centers, distance from service centers, distance from administrative centers, distance from health centers, and distance from military land uses. The priority areas for generating green spaces were identified through the weights derived from the Super Decision software and multiplying these weights by the influential locational layers via the Weighted Overlay technique, followed by the integration of the weighted layers within the Raster Calculator. To address optimal coverage, this study used the Tabu Search (TS) meta-heuristic algorithm with a nearest accessibility approach. The aim was to locate the points that provide the maximum coverage pertaining to the various neighborhoods of Zabol. To this end, the geographic information of the centers of the 40 neighborhoods of Zabol were recorded.
 

Discussion and Conclusion

The scientific analysis and optimal spatial locating of urban green spaces, if they are informed by equity-based theories and the fair distribution of urban services and utilize appropriate methods and techniques, will significantly enhance the prospects for fundamental urban planning and management. The unique geographical characteristics of Zabol, along with the findings of the this study, demonstrated that the equitable distribution of green space commensurate with minimal standards, has not been realized across the city's different zones. Moreover, different issue such as the city’s border location, the flight of capitals, persistent droughts, and the scarcity of water resource, have severely hampered the optimal allocation of urban green spaces. The novelty of this study in contrast to previous studies on the locating of urban green spaces, lies in its methodological precision. Privious studies have offered a broad spectrum of potential sites in this city; however, the implementation of all these options was often rendered impracticable due to the constraints of limited allocated resources, frequently complicating the decision of executive bodies in determining the most optimal and desired alternative. To surmount this difficulty, the current study utilized the Tabu Search (TS) metaheuristic algorithm model for the hub location problem with a nearest accessibility approach. This enabled the identification of sites that afford greater spatial coverage across the distinct neighborhoods of Zabol. Consequently, the core distinction 
between the current and previous studies is the omission of previous research of cutting-edge tools and method for data analysis and green space allocation, such as meta-heuristic algorithms and novel mathematical models. The results of the Tabu Search meta-heuristic model for the hub location problem showed that this model not only significantly help for selecting the final research zones but also effectively delineates the sphere of influence of the neighborhoods. More importantly, it clarifies the differentiated coverage status of neighborhoods regarding green spaces and represent an effective step toward smarter and more informed planning for the city of Zabol.