Urbanization describes the process of rural-urban conversion, which is the result of population migration, economic development, and social progress, and it is an inevitable process of development in all countries worldwide(Xu and Jiao 2021). Urbanization has promoted the migration of rural populations to cities, as well as the spread of urban lifestyles(Wang et al. 2018), the expansion of urban space, and the transformation and upgrading of industrial structures(Yue et al. 2021). Moreover, urbanization also promotes the generation and diffusion of technological innovation through human capital accumulation and information exchange networks(Cheng 2009), thus contributing to rapid economic development. However, the urbanization process is accompanied by industrial production, land use sprawl, energy consumption and other factors, leading to increased emissions of airborne respirable particulate matter such as haze pollution, mainly manifested in the PM2.5 concentration(Wang et al. 2018; Wang and Tang 2019; Xie et al. 2017). PM2.5, the main component of haze, can enter the human lungs and bloodstream through the respiratory tract(Tu and Tu 2018), damaging the respiratory and cardiovascular systems and thus negatively affecting the global ecological environment and residents’ health, economic and social activities(Lelieveld et al. 2015). PM2.5 prevention and control have become common problems that need to be faced globally(Squizzato et al. 2018). To alleviate haze pollution and promote sustainable urban development, building inclusive, resilient, low-carbon and safe cities has become a consensus worldwide(NDRC 2020).
To solve the environmental problems caused by urbanization, attention has gradually shifted from high-speed urbanization to high-quality urbanization(Xu and Jiao 2021), i.e., new-type urbanization. The new-type urbanization is people-oriented, takes people’s livelihoods into consideration(Yu 2021), and humanism is the core aspect of new-type urbanization planning(Chen et al. 2019). The final target of new-type urbanization is the integration of urban and rural areas, which makes citizens share a significantly improved quality of life and experience a sense of well-being(Ni 2013). China is one of the smokiest countries in the world, and it has witnessed high-speed urbanization over the past few decades and has recently paid close attention to new-type urbanization. Figure 1 shows the change in urbanization and PM2.5 concentration in China. The urbanization rate of China’s resident population has reached 63.89% by the end of 2020, and urban land is also expanding rapidly. Correspondingly, the PM 2.5 concentration first increases and then shows a downward trend, which results from China’s policy on environmental governance and the consequence of the shift from traditional urbanization to new-type urbanization. The blind expansion of Chinese cities has brought about severe haze pollution(Xu and Chen 2019), which in turn restrains urbanization by hunting city citizens’ health and causing residents to flee cities(Yuan et al. 2018). Consequently, it is necessary to change traditional urbanization to new-type urbanization. The Chinese government has published an official document Outline of the 14th Five-Year Plan (2021–2025) for National Economic and Social Development and Vision 2035 of the People’s Republic of China, emphasizing “improving the quality of urbanization” and “deeply promoting the new-type urbanization strategy with people-oriented”. The concept of new-type urbanization incorporates the national ecological civilization construction, aiming at reducing pollution. However, there is a lack of systematic analysis of whether new-type urbanization could realize pollution reduction and the acting path in the process.
The existing studies focused on the relationship between urbanization and air pollution, including PM2.5, have been discussed in the following three strands. The first strand of the core research topic is the relationship between urbanization and air pollution. By employing different data samples and empirical methods, some scholars have found that urbanization exacerbates haze pollution(Li et al. 2015; Wang et al. 2020; Luo et al. 2021), while others have found that urbanization suppresses air pollution(Wang et al. 2019; Luo et al. 2018), and the remaining scholars have found that urbanization and haze pollution have nonlinear relationships, such as the “U” type(Gan et al. 2020) or inverted “U” type(Liu et al. 2020; Lin and Zhu 2018). In addition, the relationship between the above two has significant temporal and spatial differences(Yang et al. 2021). The second trend is to discuss the influence of urban form shaped in the urbanization process on haze pollution during urbanization and to explore the impact on air quality by combining urbanization with other factors, such as industrial structure and economic growth(Yuan et al. 2018; Lu et al. 2021; Han et al. 2018). For example, Lu et al.(Lu et al. 2021) found that urban expansion mainly influences air pollution through the scale effect, technology effect, and industry effect, whereas there is a “double-edged sword” effect in which urbanization may worsen air pollution by promoting public transportation and increasing traffic congestion. The third core issue is to study the influencing mechanism of urbanization on haze pollution. Most studies concentrated on a special study area(Wei et al. 2021; Fang et al. 2020; She et al. 2021) and research at a national level. For example, Wang et al.(Wang et al. 2018) measured urbanization as the proportion of the urban population and found that urbanization can influence industry, environmental protection and clean energy consumption, thus impacting PM2.5 concentrations.
Related to the impact of new-type urbanization on environmental pollution, Li et al.(Li et al. 2022) used the new-type urbanization pilot policy to construct a DID model and argued that new-type urbanization can significantly alleviate haze pollution. Wang et al.(Wang et al. 2019) concluded that new-type urbanization indirectly curbs \({\text{C}\text{O}}_{2}\) emissions by eliminating the rebound effect of energy-saving technologies on \({\text{C}\text{O}}_{2}\) emissions.
Conclusively, studies on the influence of urbanization on haze pollution have focused more on the quantitative relationship between the two, and the influencing mechanism studies usually ignore the interaction effect between urbanization and its mechanism variables in impacting PM2.5. Moreover, research on the effect of new-type urbanization, let alone the impact and influencing mechanism of new-type urbanization on PM2.5, is scarce.
Therefore, to fill this part of the research gap, this paper takes China as a study case and focuses on people-oriented new-type urbanization, theoretically analyzing new-type urbanization’s impact on haze pollution by affecting the level of intensive urban land use, industrial structure and technological innovation, then applying the STIRPAT model and combined with interaction effects for empirical testing. Additionally, we further investigated the effect and its influencing mechanism of new-type urbanization on haze pollution in different regions in China, which could provide effective information on how to advance the Chinese new-type toward a more harmonious direction.
The marginal contribution of this study was that, first, based on people-oriented new-type urbanization, this study selects relevant indicators and uses the entropy method to measure the new-type urbanization and explore its impact on haze pollution. Second, the previous literature tended to ignore the existence of an interactive relationship between new-type urbanization and its influencing mechanisms; therefore, the STIRPAT model combined with interaction effects is used for empirical analysis. This may provide a theoretical basis and policy reference for the country in promoting the construction of new-type urbanization, realizing green and sustainable urban development.
The study processes are as follows. Section 2 interprets the theoretical influencing mechanism of new-type urbanization on haze pollution. Section 3 introduces the data processing and research methods. Section 4 analyzes and discusses the empirical results. Section 5 provides conclusions, offers policy implications, states the limitations and summarizes future works.