The built environment, purpose-specific walking behaviour and overweight: evidence from Wuhan metropolis in central China.

The impact of objective and subjective environmental factors on health outcomes has been a topic of significant debate, with a growing body of research acknowledging the role of a physically active lifestyle in promoting health. However, consensus regarding their precise influence remains elusive. This study contributes to these discussions by exploring how individual health outcomes correlate with transport and leisure walking behaviours, set against both the objective and subjective aspects of environmental influences in the context of Wuhan, an inland Chinese megacity. Street view images, multi-source geospatial data and a questionnaire survey were employed to characterise the "5D + Greenery" objective and perceived characteristics of the neighbourhood environment. Multi-group structural equation modelling was utilised to unravel the complex relationship and gender heterogeneity among environmental factors, purpose-specific walking, and overweight. Our results suggest that both objective land use diversity and perceived convenience are significantly associated with overweight. The accessibility of local service facilities and visible greenery promote both transport and leisure walking. While perceived neighbourhood safety encourages transport walking, perceived walkability is positively correlated with leisure walking. Notably, leisure walking, usually considered beneficial, presents a positive association with overweight conditions, acting as a mediation. Gender disparities exist in pathways between the environment and purpose-specific walking, as well as weight. The findings lend support to the planning of an activity-supporting built environment as a crucial strategy for obesity prevention.

Spatiotemporal Analysis of Gastrointestinal Tumor (GI) with Kernel Density Estimation (KDE) Based on Heterogeneous Background.

The purpose of this study is to explore hotspots or clusters of gastrointestinal tumors (GI) and their spatiotemporal distribution characteristics and the changes over time in 293 villages and communities in Jianze County, central China, through the kernel density estimation (KDE) method based on the rarely considered heterogeneous background. The main findings were: (1) Heterogeneous background impact: there were substantial differences in the GI case rate among people of different ages and genders in Jianze County. Specifically, the GI case rate was significantly higher in the elderly population over 65 than in the population under 65, and higher in men than in women. (2) GI in Jianze County exhibited spatial specific and aggregated hotspots. The high-value spatial clusters were mainly located in Hujindian Town in the northern county, Wupu Town and Geputan Town in the middle, and Xiaxindian Town in the south. Some villages had persistent hot spots for multiple years. (3) Most GI hotspots in Jianze County were concentrated in areas with both high density of local chemical plants and with water systems in the neighbourhood. We expect that this study provides a scientific basis for exploring unknown risk factors of tumor occurrence from a spatial perspective in the future.

Global impacts of future urban expansion on terrestrial vertebrate diversity.

Rapid urban expansion has profound impacts on global biodiversity through habitat conversion, degradation, fragmentation, and species extinction. However, how future urban expansion will affect global biodiversity needs to be better understood. We contribute to filling this knowledge gap by combining spatially explicit projections of urban expansion under shared socioeconomic pathways (SSPs) with datasets on habitat and terrestrial biodiversity (amphibians, mammals, and birds). Overall, future urban expansion will lead to 11-33 million hectares of natural habitat loss by 2100 under the SSP scenarios and will disproportionately cause large natural habitat fragmentation. The urban expansion within the current key biodiversity priority areas is projected to be higher (e.g., 37-44% higher in the WWF's Global 200) than the global average. Moreover, the urban land conversion will reduce local within-site species richness by 34% and species abundance by 52% per 1 km grid cell, and 7-9 species may be lost per 10 km cell. Our study suggests an urgent need to develop a sustainable urban development pathway to balance urban expansion and biodiversity conservation.

Spatial Characterization of Urban Vitality and the Association With Various Street Network Metrics From the Multi-Scalar Perspective.

In the context of rapid urbanization in developing countries, the spatial organization of cities has been progressively restructured over the past decades. However, little has been done to understand how the physical expansion affected the reorganization of socioeconomic spaces in cities. This study explores the association between various street network metrics and urban vitality and how it changes across different scales using geographic big data through a case study of Wuhan, China. Urban vitality is characterized by four components: concentration, accessibility, livability, and diversity. The new technique of spatial design network analysis (sDNA) is employed to characterize street network metrics, including connectivity, closeness, betweenness, severance, and efficiency, with 16 localized network variables. Furthermore, the stratified spatial heterogeneity between street network metrics at multiple scales and the four components of urban vitality is investigated using the Geodetector tool. First, concentration, accessibility, and diversity decline with distance from the urban center, whereas livability has a fluctuating upward trend with distance from the urban core. Second, the correlation between street network characteristics and urban vitality is sensitive to different spatial scales. Third, connectivity explains the largest amount of the variance in urban vitality (over 40%), while both betweenness and closeness explain roughly 28% of urban vitality. Efficiency and severance contribute 22 and 10% to the spatial heterogeneity of urban vitality, respectively. The study sheds light on the mechanisms between street configurations and urban vitality from the multi-scalar perspective. Some implications are provided for the improvement of the streets' urban vitality.

Interaction between urbanization and the eco-environment in the Pan-Third Pole region.

Due to the high ecological vulnerability of the Pan-Third Pole region and the complexity of its ecological process, the impact of urbanization on the ecological environment (eco-environment) in this specific region attracts global attention. Here, we established an effective framework to evaluate the coupling coordination process of urbanization and eco-environment, and investigated the spatial distribution and dynamic evolution of this coupling coordination. Results showed that the Pan-Third Pole is undergoing an accelerated process of urbanization. Meanwhile, the overall eco-environment has profoundly changed from an ecological reserve to an ecological deficit. The coupling degree between urbanization and eco-environment shows an upward trend, and the decoupling process dynamically changes between various types. Regional convergence is remarkably embodied in the coupling and decoupling types. We found four coupling categories and three decoupling categories for the interaction between urbanization and eco-environment. Among them, the first coupling category contains 35 countries, which maintained a basically coordinated pattern with eco-environment lag. The initial urbanization level of the first category was higher than 35%, indicating that countries with higher urbanization levels were more likely to achieve coordinated development between urbanization and eco-environment. There was a noteworthy "path-dependence" in the evolution of the coordinated relationship between urbanization and eco-environment in the Pan-Third Pole. These findings will have important policy implications for decision-makers to explore coordination and sustainable development path for urbanization and eco-environment conservation.

The influence of environmental efficiency on PM2.5 pollution: Evidence from 283 Chinese prefecture-level cities.

Environmental inefficiency caused by the extensive economic growth pattern is considered a critical driver of the unprecedented PM2.5 (fine particulate matter) pollution in China. However, the nexus between environmental efficiency and PM2.5 concentrations has rarely been examined. We used a recently developed data envelopment analysis method to measure environmental efficiency, environmental total factor productivity, and their compositions in China at the prefecture level from 2003 to 2013 and examined the effects of environmental efficiency on PM2.5 pollution. The results indicated that improvements in environmental efficiency significantly ameliorated PM2.5 pollution. The effect of technological progress on PM2.5 reduction is limited, but the pure efficiency and scale efficiency promoted by enhanced management level and optimized production scale strongly contribute to PM2.5 mitigation. The significant spatial spillover of environmental efficiency and PM2.5 pollution introduces challenges and opportunities for lowering PM2.5 emissions. The impact of environmental efficiency on PM2.5 pollution exhibits significant spatiotemporal heterogeneity, and the strength of influence tends to increase with PM2.5 concentration and become more pronounced over time. Furthermore, several socioeconomic factors are related to PM2.5 pollution, which implies that PM2.5 control is a complex system and requires a comprehensive policy mix.

Characterizing Horizontal and Vertical Perspectives of Spatial Equity for Various Urban Green Spaces: A Case Study of Wuhan, China.

Equity has been a major concern of urban green space provision. Whether the urban green spaces are equitably provided for socially disadvantaged groups is an important issue in the field of social and environmental justice. This topic is particularly significant in fast-growing Asian countries like China experiencing widening income disparity. This paper examines whether and to what extent the different green spaces (including public parks and urban vegetation) are equitable for all populations (referring to horizontal equity) and also for different social groups (referring to vertical equity) in this typical inland city-Wuhan, China. A novel indicator combining proximity and quality is presented to assess the supply of public parks. The Theil index provides a decomposable measure of overall equity across different regions and vulnerable groups. Both horizontal and vertical perspectives are compared to characterize the spatial equity of urban green spaces (including public parks and urban vegetation) across all population and across different social groups. The empirical analysis of the inland city showed that the overall supply of public parks is far more unequal than mixed or woody vegetation. The distribution of public parks is more inequitable in the outer area, whereas the distribution of mixed or woody vegetation is more inequitable in the inner area. Furthermore, the geographic detector analysis is employed to investigate the spatial relation between socioeconomic contexts and urban green spaces. The spatial heterogeneity of education and age groups is statistically significant for explaining the distribution of public parks. Meanwhile, population density clearly plays a role in the distribution of both public parks and urban vegetation. Per capita income can explain 26% of the distribution of public parks but is not significantly associated with mixed or woody vegetation. Finally, the vertical equity of urban green space is also examined in this paper that the vulnerable groups in the inner area, such as females, residents with low education, children, and the elder suffer from highly unequal accessibility to parks, whereas the vulnerable group in the outer area, such as the migrants gets unequal access to parks.