Morphological and fractal diagnostics for sustainable transport planning in sensitive tourism landscapes

Managing sustainable transport access to pristine natural heritage sites without triggering ecological degradation is a critical planning challenge for tourism-driven regions within complex landscapes. This study focuses on morphological and fractal diagnostics for sustainable transport planning to unravel challenges associated with accessibility in sensitive tourism landscapes. Specifically, it investigates the severe inaccessibility of Cala Mariolu, a globally renowned beach in Sardinia, Italy, by developing a novel diagnostic framework that integrates fractal analysis of road networks with quantitative topographic assessment. Using GIS-based spatial analysis, the structural connectivity and terrain constraints of the municipalities of Nuoro and Baunei were quantified and compared. Results reveal a significantly more fragmented and less connected road network in the coastal city of Baunei compared to the urban hub of Nuoro. Crucially, this disparity is driven primarily by steeper average slopes rather than general terrain ruggedness. This relationship was synthesised into a new Terrain Connectivity Constraint Index (Ti), quantifying the landscape's inherent limitation on network development. The findings provide a robust, context-sensitive diagnostic methodology for diagnosing the root causes of transport inequity. This study quantifies that the terrain in high-constraint coastal areas can reduce the geometric potential for creating well-connected transport pathways by 46% compared to adjacent urban hubs, providing critical insight for targeting adaptive infrastructure and fostering equitable access in environmentally sensitive regions.