Urban-rural equivalent integration signifies a dynamic process wherein urban and rural areas substantially realize interactive population mobility, equitable land valuation and tenure, synergistic industrial chains and agglomerations, harmonized infrastructure deployment, equitably accessible public services, collaborative ecological conservation and governance, and integrated information networks. This constitutes the ultimate objective of urban-rural integrated development under the paradigm of Chinese-style modernization. The core tenet of urban-rural equivalent integration is the equivalence of quality and well-being of life across urban and rural settings, represented by diverse lines of equivalence. Throughout distinct phases of urbanization and urban expansion, the fluctuation of urban-rural equivalent lines and the degree of urban-rural integration exhibit variability, theoretically charting an evolutionary trajectory characterized by an initial gentle gradient, followed by a steep ascent, and culminating in a return to a gentler slope. The driving mechanisms for urban-rural equivalent integration encompass identity equity for urban and rural residents, free flow for urban and rural construction land, intelligent mobile connectivity across urban-rural areas, market-based adjustment, and policy interventions. Quantitative indicators of urban-rural equivalent integration include 31 indicators across five dimensions: living standards, infrastructure, public services, ecological environment, and informatization. Empirical evidence from 1980 to 2023 indicates that China's overall urban-rural equivalent integration predominantly remained within a medium stage (30%-60%), while some indicators achieved a medium-high stage (60%-90%), demonstrating a progressive trajectory towards high equivalence. Notably, the urban-rural living standards and the urban-rural informatization exhibit a medium-high stage of equivalent integration, and the urban-rural infrastructure and public services are situated at a medium level, whereas the ecological environment persists in a state of non-equivalence (< 30%). Conclusively, while the trajectory towards high urban-rural equivalent integration remains a protracted and challenging endeavor, the outlook for achieving such integration is nonetheless optimistic. This research offers significant theoretical underpinnings and pragmatic guidance for advancing urban-rural profound integrated development in China.

Cross-regional urban-rural integrated development is a significant component of national urban-rural integration. It is influenced by multiple factors, including institutional arrangements, factor flows, facility connectivity, industrial coordination, ecological environment, and market demand. Such integration is driven by institutional coordination and guidance, market-based allocation of factors, spatial integration support, industrial collaboration, ecological value conversion, and market demand assurance. However, currently, it faces challenges including administrative barriers, institutional differences, uneven resource endowments, and fragmented public services. Taking the demonstration zone of green and integrated ecological development of the Yangtze River Delta as a case study, this paper systematically explores the driving mechanisms and practical pathways for cross-regional urban-rural integrated development. The practical pathways are summarized as a "four-in-one" approach, comprising coordinated urban-rural planning and governance systems, market-based allocation of urban-rural resources, shared provision of urban-rural public services, and unified formulation and implementation of urban-rural policies. Specifically, this includes: transitioning from localized separate management to standardized regional co-governance, enabling coordinated planning and standards; shifting from administrative barriers to market-driven mechanisms, strengthening market-based resources allocation; moving from localized provision to cross-regional sharing, ensuring equal access to public services; and evolving from fragmented policy-making to unified policy implementation, aligning policy action across regions. These pathways facilitate the progressions of regional urban-rural governance from "coordination" to "symbiosis", offering a "Chinese approach" to overcoming cross-regional institutional constraints and advancing high-quality urban-rural integration. The findings provide valuable insights for promoting cross-regional urban-rural integrated development.

The transportation system functions as an essential connection between urban and rural regions. It offers both physical connectivity and service functionality. It significantly contributes to facilitating the movement of resources, regional integration, and accessibility to public services. Addressing the limitations of existing research, which primarily focuses on the physical connectivity of transport infrastructure while overlooking its role in supporting public service accessibility and spatial equity, this study constructs a two-dimensional, three-level evaluation framework covering "infrastructure integration" and "functional coordination". This paper provides an empirical analysis with a case study of the Beijing-Tianjin-Hebei (BTH) metropolian area. Based on a 1-km grid, the study measures the level and spatial heterogeneity of urban-rural transport integration.The results indicate that: (1) urban-rural transportation integration in the BTH region remains generally low, displaying a concentric pattern characterized by a "core-periphery" gradient. (2) Counties (districts) surrounding central cities benefit from urban functional spillovers and network density, showing high integration levels; areas along transport corridors and in the urban-rural transition zone exhibits a "strong infrastructure, weak service" status; mountainous counties (districts) are weak in both functions and facilities, representing key areas for improving integration. (3) The significant spatial disparity between transportation infrastructure and public services provided in prefecture-level cities is recognized as the primary cause of spatial inequality in urban-rural transportation integration levels. By emphasizing a coordinated perspective of "infrastructure-function", this paper addresses the limitations of previous studies that focused mainly on physical infrastructure while ignoring transportation service function aspects. It emphasizes the role of urban-rural transport integration in promoting public service equalization and equal opportunities, providing a quantitative basis for the coordinated allocation of transport resources and public services. It also offers empirical support for understanding the spatial mechanisms and governance strategies of urban-rural transport integration.

As global warming continues to intensify, urban areas are increasingly exposed to severe thermal stress. Addressing this challenge requires not only city-level adaptation strategies but also integrated, landscape-scale coordination across urban and rural systems. However, in the current trajectory of urban-rural integration, urban and rural landscapes are often treated in isolation. Existing research has largely focused on intra-urban cooling solutions, with limited attention to the coupled dynamics between landscape patterns and thermal environments along urban-rural gradients. To bridge this gap, we investigate three major urban agglomerations in eastern China—the Beijing-Tianjin-Hebei region, the Yangtze River Delta, and the Guangdong-Hong Kong-Macao Greater Bay Area—by constructing a multi-level urban-rural gradient framework based on multi-temporal 30-m land cover data (2000-2020) and annual MODIS land surface temperature (LST) products. We integrate landscape metrics, trend tests, propensity score matching (PSM), and machine learning to quantify gradient-scale landscape reconstruction and thermal evolution and to reveal how rural landscapes regulate urban thermal effects. Our results reveal that: (1) thermal evolution exhibits pronounced differentiation along urban-rural gradients, with the strongest warming trends occurring in urban expansion and peri-urban edges. Rapid impervious surface expansion and cropland loss, coupled with intensified landscape fragmentation, make these zones more thermally sensitive. Urban cores tend to show saturation-like stability in LST. (2) PSM identifies gradient "net" thermal effects attributable to socioeconomic activities and anthropogenic heat, which generally decline from urban to rural areas across all agglomerations, with the strongest effects observed in the Yangtze River Delta and the weakest in the Beijing-Tianjin-Hebei region. (3) Optimizing rural landscape composition and configuration can significantly mitigate urban heat island intensity across urban gradients, with forest and cropland proportions as key regulators showing nonlinear and threshold responses, while higher landscape connectivity helps stably reduce urban heat accumulation. This study advances a coupled urban-rural perspective on urban heat island dynamics and provides theoretical insights for spatial governance and thermal risk mitigation under integrated urban-rural development.

The dual pressures of growing water demand from multiple sectors and rigid constraint on available water resources have intensified urban-rural water supply-demand conflicts, leading to transformations in China's water use patterns. While previous studies have laid a solid foundation for understanding water use patterns and water scarcity, urban-rural water competition dynamics remain understudied. Based on water use and water availability data in 341 prefecture-level administrative units of China during 1965-2023, this study quantifies water deficits and identifies the onset year when water competition starts and the frequency of water competition for different administrative units. The relative contributions of urban versus rural water uses to deficit are further assessed. Key findings reveal that China's urban-rural water deficits followed an inverted U-shaped trend, peaking in 2014, accounting for 35.3% of the total water use, with competing units expanding spatially. Administrative units facing water deficit are classified into three categories, i.e., urban-rural dual-deficit units, rural-deficit units, and urban-deficit units. Water deficit shows a clear hierarchy pattern with dual-deficit units dominating across China, followed by rural-deficit units, while urban-deficit units are least common. This reveals that water competition primarily stems from concurrent growth in urban and rural water demands. These analyses advance understanding of urban-rural water use and deficit dynamics in China and provide scientific support for developing regionally differentiated water governance policies and coordinated allocation mechanisms.

Understanding the evolutionary patterns and dynamic mechanisms of global urban-rural settlements is essential for advancing global sustainability and fostering integrated development. To address the "urban-biased" limitation of previous global studies, this research employs the 100-meter resolution GURS dataset and a trajectory-capturing algorithm to quantify settlement evolution from 2000 to 2020. By integrating the XGBoost and SHAP machine learning methods, we systematically analyze the differentiated dominant drivers, non-linear response mechanisms, and interaction effects of 12 influencing factors on settlement evolution. Results show that global settlements evolved at diverging rates during this period: urban expansion decelerated while rural expansion accelerated. This trend was most prominent in developing regions, accompanied by significant rural-to-urban spatial conversion. Regarding evolutionary trajectories, both urban (87.6%) and rural (71.5%) settlements were dominated by "Continuous Increase", yet rural settlements exhibited significantly higher volatility and shrinkage. Influence analysis identifies population size as the primary factor for both systems. However, urban evolution is closely coupled with socioeconomic factors such as industrial structure and GDP per capita, while rural evolution is uniquely influenced by land use intensity and population out-migration. Further analysis uncovers complex non-linear relationships between these factors and settlement evolution, categorized into "changing marginal effects" and "turning points". Moreover, population size functions as a core node in the influence network, interacting with industrial structure and urbanization rates to shape complex evolutionary pathways. This study deepens the understanding of global urban-rural dynamics and provides a scientific basis for tailored urban-rural governance strategies across different development stages.

Urban-rural public service integration is crucial for improving residents' well-being and achieving spatial equity, and represents a key foundation for promoting urban-rural integration and new-type urbanization. Building on a "people-facility-flow" interactive framework, this study develops a second-order accessibility model that incorporates spatial mobility linkages and dynamically defined geographic proximity. Using healthcare services in the Xi'an metropolitan area as a case study, the model is systematically applied to evaluate urban-rural public service integration in terms of accessibility and spatial equity. The results show that: (1) Population mobility is a key driver of urban-rural public service integration in metropolitan areas. The dynamic redistribution and high mobility of the population can not only reshape the spatial pattern of service accessibility but also influence supply-demand relationships and the efficiency of public service allocation. (2) Population mobility generally exerts a positive effect on urban-rural public service integration. The impact exhibits significant temporal threshold effects and marked spatial heterogeneity, with the strongest effects observed under shorter temporal thresholds and in inner suburban areas. (3) Population mobility does not uniformly enhance urban-rural public service integration; at small and medium spatial scales, it may still generate potential equity risks. By incorporating the high-mobility characteristics of metropolitan areas, this study extends the evaluation of urban-rural public service from a static supply-oriented paradigm to a dynamic analytical framework coupling "people-facility-flow". The findings highlight the critical role of population mobility in shaping urban-rural public service integration in metropolitan areas and provide insights for promoting people-centered urban-rural integrated development.