Migration across the urban hierarchy: Has China’s urbanisation transitioned from the primate city stage to the secondary city stage?

Sometimes we notice that populations concentrate in mega cities, while at other times, people tend to move to smaller cities. Why is there such a divergence in different periods of time? How can we distinguish the turning points of migration trends and urbanisation stages?

China seems to be experiencing this transformation period. Over the past four decades of rapid urbanisation, primate cities like Shanghai and Beijing experiencing significant influxes of migrants. These cities are viewed as the country’s “first-tier cities”. However, in recent years, there has been a noticeable trend of people “escaping from primate cities”, possibly due to high housing prices or strict hukou policies.

Meanwhile, secondary cities, known as “new first-tier cities”, are emerging as viable alternatives, such as Hangzhou and Chengdu. This recent migration phenomenon suggests early signs of a potential transition in urbanisation stages and migration trends.

Who are the individuals driving this shift? We consider them as migrants across the urban hierarchy. Since migration is a selective process, those moving down the urban hierarchy might possess distinct demographic characteristics compared to those moving upward.

Therefore, we aim to distinguish China’s current urbanisation stage and explore the demographic characteristics among cross-level migrants to understand concentration and deconcentration trends. To achieve this, we combined the theory of differential urbanisation and migrant selectivity.

The theory of differential urbanisation identifies three main stages based on migration growth in cities at different levels. The primate city stage witnesses populations concentrating in the primate cities. However, when these cities become overcrowded, migration towards secondary cities becomes dominant, marking the onset of the secondary city stage. Eventually, during the small city stage, a growing population seeks more favourable surroundings in smaller cities.

Our findings indicate that China is currently in the intermediate primate city stage but has not yet reached the secondary city stage. Following the theory of differential urbanisation, we predict that people will continue to concentrate in both primate and secondary cities, with secondary cities experiencing more rapid growth. However, small cities are expected to continue losing population in the short term.

In the current urbanisation stage, upward migration across the urban hierarchy is driven by younger, well-educated individuals with higher incomes and a lower likelihood of marriage or parenthood. On the other hand, “escaping from primate cities” seems to occur mostly among the group of onward or return migrants with relatively low education and income.

Interestingly, these migration patterns deviate from the concept of productionism and environmentalism in the theoretical framework of differential urbanisation. According to this concept, highly educated individuals with high incomes tend to prioritise quality of life and move down the urban hierarchy. However, our research suggests that this concept might be more applicable to specific urbanisation stages. During the primate city stage, characterised by concentration, educated and high-income migrants tend to concentrate in larger cities due to economic factors. In contrast, during the secondary and small city stages, as deconcentration occurs, the expansion of primate cities brings about challenges such as poor environmental conditions, prompting some affluent and well-educated individuals to move downward.

In conclusion, our paper extends the theory of differential urbanisation by examining urbanisation stages through the individual characteristics of cross-level migrants. This approach contributes to existing studies that have primarily relied on aggregate information to distinguish urbanisation stages. This paper also introduces a migration-oriented theoretical framework to examine the evolution of primate cities and secondary cities, offering an addition to the current spatial and functional viewpoints. Furthermore, our research provides valuable insights for policymakers at both the national and city levels to develop population growth plans and effectively respond to future urbanisation processes.

Read the full article on Urban Studies OnlineFirst here.