Public Service Facility Configuration of Agricultural Counties in the Central and Western Regions Based on the Improved Optimal Supply-Demand Accessibility Method

Influenced by Split Urbanization and Dependent Urban-rural Relations, agricultural counties in the central and western regions generally face issues such as imbalanced spatial distribution of public service facilities, declining service quality, and insufficient accessibility. This study takes Pucheng County in Weinan City as a case study and constructs a research framework of “demand analysis - accessibility measurement - allocation optimization”. First, the permanent population and its movement network are identified based on cell phone signaling data, and the complex network analysis method is used to determine the usage preference and actual demand. Secondly, the coverage and accessibility of public service facilities are quantitatively evaluated through the optimal supply-demand allocation model. Finally, considering factors such as supply-demand relationship, coverage rate, and accessibility within the county’s public service facilities, a systematic allocation optimization plan is proposed. The findings reveal: (1) According to the population flow characteristics, the administrative villages in Pucheng County are classified into high-inflow type (11 villages), inflow type (38 villages), balanced type (49 villages), outflow type (128 villages), and high-outflow type (129 villages), with corresponding supply adjustment coefficients of 1.58, 1.32, 1.03, 0.78, and 0.54, respectively. (2) Based on the 30-minute walking service radius, the optimized coverage rates for educational, medical, and elderly care facilities in the county improve from 71.44%, 54.75%, and 35.17–82.40%, 84.56%, and 79.13%, respectively. (3) For medical and elderly care facilities, an innovative allocation mode of “precise gap-filling + medical-care integration + mobile services” is proposed. This study not only provides practical guidance for the allocation of public service facilities in agricultural counties in the central and western regions, but also offers a theoretical basis for facility planning decisions in areas with frequent population flows and weak public services.