Exploring Spatial Patterns in Samsun, Turkey Road Networks through GIS and Fractal Analysis

Transportation networks are inherently complex systems, and fractal analysis provides a robust approach for spatially characterizing their complex geographical structures. This study employs GIS and fractal analysis to investigate the road networks of Samsun Province, Turkey, at the district level. Fractal dimensions were calculated using the box-counting method to assess the access depth-coverage degree of road networks across 17 districts, while the lacunarity index, calculated from the gliding box algorithm, evaluated spatial homogeneity/heterogeneity. Fractal dimension values ranged from 1.526 to 1.690, and lacunarity indices range from 0.478 to 1.384. Correlation analyses explored the relationships between these metrics and urban parameters, including population, district area, number of road segments, road length, built-up area, population density, road density, built-up area density, and the socioeconomic development index (SEDI). The fractal dimension correlated most strongly with SEDI (0.835), while the lacunarity index was most closely associated with population density (0.908). Both metrics exhibited weak correlations with district area and road length. The findings revealed that increased population and built-up areas contribute to more complex road networks, enhancing access depth-coverage degree but also amplifying spatial inequalities. The joint assessment of the fractal dimension and lacunarity index, along with the quantification of their relationships with urban parameters, provided a comprehensive spatial evaluation that offers important insights for urban development and road network planning.