Understanding archetypal spatial gradient patterns in urban economic, population and air quality nexus: New insights from a geographic-process perspective

• Published in: Sustainable cities and society 2023-08, Vol.95, p.104596, Article 104596
• Main Authors: Zhang, Ping, Wu, Hao, Zhang, Jun, Sun, Qiangqiang, Ji, Zhengxin, Lin, Xin, Chen, Jiongbin, Sun, Danfeng
• Format: Article
• Language: English
• Subjects: A geographic-process perspective; Archetype analysis; Economic-population-air quality nexus; Spatial trajectory models; Urban development intensity gradients
• ISSN: 2210-6707; 2210-6715
• DOI: 10.1016/j.scs.2023.104596

•A spatially-explicit approach was proposed to explore interactions between three urban elements.•We investigated spatial gradient patterns of three socio-ecological urban elements along UDI.•Six classical archetypes in urban economic-population-air quality nexus were identified.•This approach offers general and comparable templates for sustainable urban spatial management. The increasing complexity of urban social-ecological dynamics have presented potential challenges on achieving sustainable development goals (SDGs). However, little is known about heterogenous patterns with respect to the multi-dimensional contexts of cities, especially from spatially-explicit and system-integrated perspectives. Here, we developed two spatial trajectory models (exponential and logistic function) from a geographic-process view to quantify spatial gradient patterns of economic-population-air quality nexus along urban development intensity (UDI), and explored their interactions from archetypal analysis that combines static spatial gradient patterns and change magnitude of essential attributes (i.e., background baseline, concentration level) across 32 major cities in China. We found nighttime light intensity and population density experience an accelerated exponential increase, whereas most of PM2.5 concentrations tend to grow in an S-shape manner along a rising UDI gradient. And the evolution dynamics of these three elements are not consistently matched in spatial distribution and aggregation patterns during 2000–2018. Specifically, although the higher economic baseline and more balanced pattern of all the typical 32 cities have been relatively widely achieved during the nearly past two decades, over 80% of sample cities are still currently facing a declining baseline and more concentration level of population density. And nearly half of the cities tend to follow a path of generating PM2.5 pollution that transgressed the Level II concentration threshold of China Ambient Air Quality Standard (GB3095–2012) (>35 μg·m−3) when accompanied by a slightly enhanced spatial aggregated pattern. In terms of archetypal analysis of 32 cities, six regime shifts provide new insights into the prevalence of trade-offs and synergies between urban economic-population-air quality nexus along urbanization levels, basically following the hierarchy and adaptive cycle pathways. Therefore, these new insights into micro- and macro- city analysis allow for spatial refinement of urban internal structu