The “Integration Race” of Urban Agglomerations: How the Yangtze River Economic Belt Is Rewriting China’s Urbanization Logic

An Underestimated Signal: The Unit of Urban Competition Is Changing

Over the past four decades, the global urban narrative has revolved around “the city”: New York, London, Tokyo, Shanghai, Shenzhen. Cities have been seen as growth engines, containers of capital, and magnets for talent. But today, what truly determines long-term competitiveness is increasingly not the GDP or skyline of a single city, but whether urban agglomerations can organize core cities, peripheral cities, county-level areas, and rural hinterlands into a resilient spatial system. Recent research on the Yangtze River Economic Belt offers a window into this shift.

A study published in 2025 in Frontiers in Sustainable Cities assessed the level of urban-rural integration in three major urban agglomerations of the Yangtze River Economic Belt—the Yangtze River Delta, the Middle Reaches, and Chengdu-Chongqing—from 2010 to 2019. The conclusions are not dramatic, but they carry structural implications: the overall level of integration rose; Chengdu-Chongqing was significantly lower than the Yangtze River Delta and the Middle Reaches; spatially, high values clustered in the east (north) and low values in the west (south); and among the drivers, the interaction effects of the non-agricultural population share, per capita arable land area, industrial structure, and other factors exceeded those of any single factor. The study also notes that fluctuations in industrial structure mirror the impact of China’s economic transformation on urban-rural integration.

If this set of conclusions is read merely as a regional policy assessment, it misses the larger questions: Why, at a stage when the urbanization rate is already high and infrastructure has been rolled out on a large scale, does urban-rural integration still show such strong spatial differentiation? Why have gaps between urban agglomerations not automatically converged with overall development? And what does this mean for the global urban system?

From “Urban-Rural Dualism” to “Urban Agglomeration Integration”

China’s urban-rural relations over the past seventy years have undergone a long-term transition from differentiation to integration. But integration is not linear. The study points out that unbalanced development, insufficient rural development, restricted two-way factor flows, and poor resource allocation remain major obstacles. In other words, the question is no longer whether cities drive rural areas, but whether cities and the countryside can form, within the same governance framework, a relationship of two-way factor flows, equal public services, and complementary industrial functions.

This contrasts with global experience. In many advanced economies, urban-rural relations have gone through a cycle of “integration—separation—integration”: early urban-rural links were close, industrialization and urbanization brought separation, and then regional policies, public services, and transportation networks reintegrated them. Theories such as urban bias, rural bias, and balanced development discuss tendencies in resource allocation, but they rarely delve into “integration” itself. China’s urban agglomeration strategy, in effect, elevates urban-rural integration to a core proposition of spatial governance.

The three major urban agglomerations of the Yangtze River Economic Belt happen to form a gradient experiment: the Yangtze River Delta is a highly urbanized region with the strongest global connections; the middle-reaches urban agglomeration bridges the east and the west, combining manufacturing and agricultural hinterlands; the Chengdu-Chongqing urban agglomeration is located in the west, where mountains and plains interlace internally, and core cities stand out while the periphery remains weak. Research shows that the integration level of Chengdu-Chongqing is significantly lower than that of the Yangtze River Delta and the middle reaches. This is not merely a gap in aggregate economic output, but a comprehensive reflection of spatial structure, industrial organization, and governance capacity.

East High, West Low: The Structural Logic Behind Spatial Agglomeration

The study observes a clear spatial agglomeration effect in urban-rural integration levels: high-value areas are concentrated in the east (north), while low-value areas are concentrated in the west (south). This is consistent with China’s long-standing demographic and economic geography—the differentiation revealed by the Hu Huanyong Line and the Kunlun–Qinling–Huaihe Line has not disappeared because of rapid urbanization. On the contrary, at the urban agglomeration scale, this differentiation reappears in more complex ways.

The high integration of the Yangtze River Delta stems not only from economic development, but also from a dense urban network, a mature county-level economy, relatively balanced public services, and highly fluid factor markets. The middle-reaches urban agglomeration occupies an intermediate position: core cities such as Wuhan, Changsha, and Nanchang drive surrounding areas, but the hinterland still faces population outflow and industrial transformation pressures. Chengdu-Chongqing presents a typical “core-periphery” structure: the dual cores of Chengdu and Chongqing stand out, while integration levels in peripheral mountainous areas and counties remain low. The study points out that within Chengdu-Chongqing, only the core cities have obvious advantages, while marginal mountainous areas form low-value zones.

This suggests a key judgment: urban agglomerations are not machines of automatic equilibrium. Transportation infrastructure can shorten time distances, but if industry, land, public services, and the household registration system are not coordinated, the spillover of core cities may be offset by the “siphon effect.” Imbalances within an urban agglomeration may be harder to govern than imbalances between cities, because they involve administrative boundaries, fiscal allocation, land quotas, and ecological constraints.

Driving Mechanisms: Interaction Effects Matter More Than Single Factors

Using the geographical detector method, the study finds that the interaction effects of factors such as the proportion of non-agricultural population, per capita arable land area, and industrial structure are significant, exceeding the influence of any single factor. This means that urban-rural integration cannot be advanced by a single policy alone. Increasing non-agricultural employment, protecting arable land, and upgrading industry—any single variable may change indicators in the short term, but only when they interact can sustainable integration take shape.

Fluctuations in industrial structure deserve particular attention. The study points out that these fluctuations reflect the impact of China’s economic transformation on urban-rural integration. When manufacturing upgrades and services expand, cities’ demand for high-skilled labor rises, and the pathways of rural labor transfer change; when traditional industries contract, county-level economies reliant on low-end manufacturing and agriculture come under pressure. Urban-rural integration is therefore not only a spatial issue, but also a function of industrial policy and macroeconomic cycles.This also explains why the Yangtze River Delta has a relatively high level of integration: it not only has stronger industrial upgrading capacity, but also a denser network of county-level economies, so that rural areas do not have to rely only on core cities. In Chengdu-Chongqing and parts of the middle reaches, by contrast, industrial transformation may create a mismatch of “urban upgrading, rural lagging behind.”

Urban Agglomerations in the Restructuring of the Global Urban System

If the Yangtze River Economic Belt’s experience is placed in a global context, several longer threads become visible.

First, urban competition is becoming regionalized. Global capital, talent, and supply chains no longer choose individual cities alone; they choose city-regions: the Greater Bay Area, the Yangtze River Delta, Greater London, the Rhine-Ruhr, and San Francisco–Silicon Valley. Transport, energy, digital, and institutional connections within urban agglomerations have become “system assets” for attracting investment. The level of urban-rural integration actually determines whether the hinterland of an urban agglomeration can provide land, labor, ecological products, and markets, thereby affecting the resilience of the entire region.

Second, urbanization in the Global South is changing the governance agenda. In the coming decades, most urban population growth will occur in Asia and Africa. The problem these regions face is not how to build new cities on blank land, but how to govern the interface between urban and rural areas: informal settlements, land tenure, food security, climate risk, and infrastructure gaps. Research on urban agglomeration integration in the Yangtze River Economic Belt provides a method for quantitative assessment and spatial diagnosis, and also reminds policymakers that urban agglomeration planning must include rural areas, rather than treating them as passive recipients of spillover.

Third, the relationship between cities and the state is changing. Urban agglomerations are increasingly becoming geoeconomic units, taking on functions of industrial policy, infrastructure coordination, climate adaptation, and population management. National strategies require urban agglomerations for implementation, while urban agglomerations require rural hinterlands to maintain food, ecological, and social stability. Urban-rural integration is therefore no longer a social policy, but a component of national spatial strategy.

Future Urban Strategy: From Expansion to Systemic Coordination

If urban-rural integration is the foundation of urban agglomeration competitiveness, then the traditional logic of urban development is becoming obsolete. In the past, the core of urban strategy was expansion: build new districts, roads, attract investment, and maximize GDP. In the future, the core will be coordination: how to allocate industry, population, land, and public services within a polycentric network; how to make rural areas not merely the “back garden” of cities, but composite spaces of production, ecology, and culture; and how to use digital infrastructure to connect remote areas while avoiding new spatial inequality.

The gradient of the Yangtze River Economic Belt shows that there is no uniform model of integration. The Yangtze River Delta needs to address excessive concentration and ecological pressure; the middle reaches need to strengthen industrial links between core cities and their hinterlands; and Chengdu-Chongqing needs to cultivate secondary centers and county-level nodes beyond its dual core. Policy priorities should include: market-based allocation of urban-rural factors, equalization of basic public services, land and ecological compensation, gradient-based industrial transfer, and balanced layout of transport and digital infrastructure. These are not short-term projects, but long-term institutional design.

Conclusion: Integration Capacity Will Become a Strategic Asset of Urban AgglomerationsResearch on the Yangtze River Economic Belt offers no startling prophecy, but it reveals a quiet structural change: as urbanization enters its second half, the competitiveness of urban agglomerations is no longer determined solely by the skylines of core cities, but by the quality of governance at the urban-rural interface. The gap between Chengdu-Chongqing and the Yangtze River Delta, the intermediate state of the middle reaches, the spatial concentration pattern of high in the east and low in the west, and the interaction effects of driving factors all point to the same thing—urban-rural integration is not a byproduct of urbanization, but the next stage of urban civilization.

The global urban system is moving from "city competition" to "urban agglomeration competition," and from "urban priority" to "urban-rural system coordination." Whoever can organize cities and rural areas into a resilient, inclusive, and long-term productive spatial network will be able to occupy a more favorable position in the global competition of the next decade. The Yangtze River Economic Belt is precisely a frontier laboratory for this integration competition.

Source: Frontiers in Sustainable Cities, “Urban–rural integration of urban agglomerations in China’s Yangtze River Economic Belt: spatiotemporal evolution and driving mechanism”, 2025. https://www.frontiersin.org/journals/sustainable-cities/articles/10.3389/frsc.2025.1528062/full