Regional differences and synergistic types of county-based urbanization and rural development in China

Urban-rural integration is the ineviatable trend in the development of urban-rural relations. Counties serve as crucial vehicles for achieving this integration of new urbanization and comprehensive rural revitalization. To reveal the spatial patterns and formation mechanisms of urban-rural synergy across Chinese counties, this study employs spatial analysis and multinomial logistic regression models using 2020 cross-sectional data from 2, 355 counties. We first explore the spatial distribution of urban-rural development and synergy typologies at the national scale, then conduct focused comparative analyses of pattern differentiation in the Yangtze River Basin and Yellow River Basin, while systematically identifying key factors influencing the probability of different synergy types.The research has four major findings. Firstly, nationally, urban-rural development exhibits a pattern of "lower levels in northeastern and southwestern regions, with localized higher levels in southeastern and northwestern areas." Within the major basins, development intensity along the Yangtze River increases downstream, while the Yellow River Basin shows higher development in its northern reaches and estuary zone but lower levels in the southern regions. Secondly, high-level synergy counties (40.3%) align spatially with major urban agglomerations; low-level synergy clusters (48.3%) concentrate in former contiguous poverty-stricken areas; urban-lagging imbalance counties (5.5%) are frequently adjacent to high-synergy counties; rural-lagging imbalance counties (5.9%) show no significant spatial clustering. Thirdly, synergy differentiation is mechanistically driven by the "population-land-industry" analysis framework: terrain constraints exacerbate imbalance whereas transportation advantages mitigate dysfunction risks; industrial upgrading suppresses low-level synergy but has limited effect on improving rural-lagging imbalance; inefficient government investment and structural contradictions in human capital hinder development. Finally, promotion pathways require spatially tailored strategies: enhancing innovation radiation in high-synergy zones; promoting eco-industrialization in low-synergy regions; facilitating industrial transfer absorption or removing institutional barriers in imbalance areas. Basin-specific priorities include: addressing low-level synergy in poverty-stricken upstream areas, the mountainous southern Jiangxi region, and the agricultural areas of northern Anhui farmer within the Yangtze Basin; strengthening the Lanzhou-Xining, Guanzhong, and Central Plains urban agglomerations to resolve the prevalent low-level synergy and rural-lagging imbalance throughout the Yellow River Basin.