ObjectivesThis study aims to: 1) Explore the mobility experiences of seniors with slow walking speeds (SSWS) in urban neighborhoods; and 2) Investigate their environmental barriers and supports.MethodsGo-along interviews were conducted with 36 SSWS residing in urban neighborhoods of Chongqing City, China. The mobility patterns and built environment factors influencing their mobility were revealed through cartographic analysis and thematic analysis.ResultsSSWS primarily focused their activities within a 400-meter radius of their homes. Built environment themes included topography, neighborhood services, sidewalks, seating, traffic safety, weather, greenery, and lighting. Significant mobility barriers included long stairs, steep slopes, fast-moving objects on sidewalks, road crossings, and fast traffic. Available handrails, nearby food-service places, ample seating, and greenery were identified as supportive factors for their mobility.ConclusionThis study stands out as the first to specifically examine the mobility of SSWS within the built environment. We suggest that SSWS should be taken into account when establishing a benchmark for general design frameworks. These improvements not only contribute to the mobility of slow walkers but also have positive impacts on the broader population.

Background: Walking is a widespread and multifaceted activity among residents in high-density cities, making assessing the neighborhood walking environments important. Existing tools for assessing walkability in high-density cities primarily focus on the immediate environment of sidewalks. However, an individual's walking behavior is influenced by environmental characteristics across multiple dimensions and scales. Consequently, based on a systematic analysis of the features of high-density cities, this study proposes the High-density Environment Assessment Tool (HEAT). This hybrid approach comprehensively assesses walkability in high-density cities by incorporating variables of neighborhood, segment (sidewalk), and crossing. Methods: The HEAT consisted of three sections with 108 items. To validate the reliability and applicability, field tests were conducted in two 15-min walkable neighborhoods with different built environment contexts in Chongqing City, China. The neighborhood section was objectively assessed using ArcGIS Software. The segment section and crossing section were audited through systematic on-site observation. Four pairs of trained raters assessed all of the segments (n = 139) and crossings (n = 123) within the two neighborhoods. The inter-rater reliability of the repeated audit data was evaluated by Kappa/Weighted Kappa or Percentage Agreement values. A webbased application was used for data collection and input. Results: For the neighborhood section, 21 assessment items were included. For the segment and crossing sections, 87 assessment items were included for the reliability test, and 84 (96.6%) of the items indicated satisfying inter-rater reliability (with Kappa/Weighted Kappa value >= 0.4 or high Percentage Agreement). In addition, the audit of each segment and crossing sample was completed in an average of 7.9 and 1.8 min, respectively. Conclusions: The results indicated that the HEAT was reliable and efficient. The HEAT provided an effective tool for assessing the walkability of the neighborhood built environment in high-density cities, thereby facilitating environmental interventions aimed at promoting walking activities.

During the past two decades discussions on urban shrinkage have been increasing in intensity, mainly due to the irresistible trends of migration, economic transformation, and the so-called "siphon effect" of large and mega cities. Yet, very few studies have tried to understand urban shrinkage from the perspective of local microscopic unit evolution. This study develops a novel model for simultaneous simulation of expansion and shrinkage (MSSES) of urban built-up areas. Starting from a microscopic basis, our MSSES can simulate both the processes and the states that lead to spatial expansion or shrinkage. A MaxEnt model is further used to investigate the driving factors of microspatial changes and compute the probabilities of shrinkage (or expansion) of urban built-up areas. Finally, it simulates the explicit layout of the spatial distribution of shrinkage (or expansion) patches with the help of a sorting cellular automata (CA) model. The validity of MSSES is verified using multisourced data from the Wuhan agglomeration, China. We show that (1) MSSES can more accurately simulate urban expansion or shrinkage than the currently widely used neighborhood-based Logistic-CA (NL-CA) and (2) MSSES has advantage in solving the commonly seen problem of "diffusion-coalescence," especially for the simulation of outlying expansion. Against the context of the Wuhan metropolitan area, we also found that overall the shrinkage trend is slowing down significantly, presenting three types of shrinkage at city-scale: remote shrinkage, peripheral shrinkage, and international shrinkage. Our study has contributions to the body of knowledge as well as practical implications for urban management and improving the sustainable development of urban areas in both China and abroad. The city we live in may be experiencing a situation where expansion and shrinkage are happening simultaneously. Hence, the simulation and prediction of temporal and spatial changes in urban expansion and shrinkage hold great importance in formulating urban policies. In this study, we propose a model capable of simultaneously predicting urban growth and shrinkage, and apply this model to the urban morphological changes in the Wuhan metropolitan area from 2000 to 2035. The simulation results demonstrate the effectiveness of this model in predicting the locations of urban expansion and contraction in advance. Furthermore, we discovered that the overall shrinkage trend is projected to significantly decelerate in the future. These findings offer support for intervention in urban planning, guiding the development of urban spaces and advancing the scientific aspects of urban planning.

Physical inactivity poses growing threats to the Chinese population,associated with booming urbanization and unfriendly living envi-ronment in recent years.This paper is a systematic review to investigate the neighborhood built environment factors correlated with physical activity in the Chinese population,including children and adolescents,adults,and the elderly.The Web of Science has been searched for articles in English,and the China National Knowledge Infrastructure has been searched for articles in Chinese.A total of 35 articles published before January 2020 have been included in this review.Then these articles are studied with a focus on six major aspects-transportation,density,design,diversity,amen-ity,and walkability-finding that the neighborhood built environment factors related to physical activity vary across age groups and different types of neighborhoods.In the context of refined community governance,future research should make further explorations from aspects including differ-ent resident groups,local characteristics of neighborhoods,built environment characteristics,research design,and other relevant variables.

社区建成环境是承载且引导居民健康行为的空间载体.推进健康社区建设的关键问题之一是了解该社区的特征和资源,以及正确认识社区建成环境如何影响个体健康.掌握科学的社区建成环境评价方法对于探索在地性的社区健康提升策略具有重要现实意义.近年来,社区建成环境审计方法常用于公共卫生领域的研究,关注微观尺度环境(如人行道、坐凳空间)的特征和质量,可以支撑更精细尺度的环境现状评估、问题研判和场景模拟分析.本文通过相关理论和实证文献的研究,解读社区建成环境审计工具的特征,识别其价值与核心,同时梳理国际上广泛应用的社区建成环境审计工具的关键信息,在此基础上构建一套适合中国城市特征、以健康为导向的社区建成环境审计工具,以期为推进健康社区建设提供方法支撑.

Public parks are critical resources for physical activity (PA). Pocket parks within neighborhoods play an essential role in the elder’ daily life. A deep understanding of pocket park use and park-based PA for older adults supports the better design of outdoor spaces. Gender differences have been confirmed in previous studies. Indeed, it was observed that more males visit parks than females, and males are likely to be vigorously active. However, almost all the studies were conducted in western countries, and none has yet focused on the Chinese elderly. The main objective of this study is to investigate gender differences in park-based PA in the Chinese middle-aged and elderly population. In Zongbei Park (Chengdu, China), video recording is used from 07:00 a.m. to 07:00 p.m. to document numbers, gender, age group, and type of activity. Demographic variations of park use patterns and energy expenditure are analyzed. The study findings indicated that most users (92.05%) were middle-aged and elderly. Significant gender variations were found in the number of total and five types of activities ( p < 0.01), respectively. Although more old males than females were observed in Zongbei Park, the total METs and mean METs per male were lower than females. A majority (65.66%) of the older adults were seen playing cards/mahjong. It will lead to a significant number of sedentary older adults. As China faces severe healthcare challenges due to the problem of aging, it becomes essential to construct age-friendly design pocket parks. More attention should be paid to address the park-based PA gender gap.

进入高质量发展阶段,文化力作为城市更新的重要动力已成共识.由于传统城市规划体系在社区层面的长期缺位,社区空间的文化价值并未得到充分识别与系统利用,随着快速推进的城市更新行动呈现"表象营造"状态而有逐渐丧失社区整体价值与内在深层结构的文化意义与精神传承之势.文章在作者2010年提出的"城市空间文化结构"概念基础上,结合十年社区实践,进一步建构"城市社区空间文化结构"基本概念,同时建立"社区空间文化要素—社区空间文化场景单元—社区空间文化结构"的解析框架及定性与定量相结合的分析方法,并以重庆市渝中区七星岗街道为例探讨社区空间文化结构思想在社区更新规划中的运用,以期丰富和深化中国城市社区更新规划理念与方法.

Green transit-oriented development (TOD) is an evolution of the TOD theory, influenced by sustainable development and green urbanism. This advancement expands the environmental and ecological dimensions of conventional TOD. However, relevant research has only just started, particularly in combination with high-density cities in Asia. This study measures the built environment of Green TOD and identifies the key factors and characteristics of the Green TOD built environment. An evaluation method for the Green TOD built environment is developed on the basis of the 5D (density, diversity, design, destination, and distance) built environment framework and combined with green urbanism theories. Data from 23 rail station areas in Singapore were collected and analyzed using factor and cluster analysis. Five factors, namely, neighborhood spatial form factor, facility completeness factor, open space factor, high-density mixed land-use factor, and walking amenity factor, are extracted. Twenty-three station areas are classified into five clusters. The characteristics and optimization strategies of each cluster are analyzed on the basis of the statistical and graphical analyses. This research displays the characteristics and typology of the Green TOD built environment in an empirical way and offers a foundation for further research in diverse urban contexts.

The increasing interest in fine-grained blocks requires a deeper understanding of the impact of block size on urban vitality. To date, limited empirical tests of the underlying relationships at the city level have been conducted using the ordinary linear-squares method, assuming a linear relationship. However, urban vitality is a complex system, thus making the use of linear regressions unfeasible because the assumption of homogeneity of variance would be violated. Therefore, the constraint line method was introduced to deepen the understanding of the relationship between block size and urban vitality. This paper employed a kernel density estimation of small catering businesses, point of interest density, social media check-in density, and comment density as proxies of urban vitality. Wuhan is the largest megacity in Central China and has been selected for this case study. When the block size increased to almost 0.08 km(2), the maximum kernel density estimation value decreased sharply from above 2.70 to 1.60; when the block size exceeded 0.30 km(2), vitality values tended to decrease very slowly. The maximum urban vitality measured by the other three indicators dropped an order of magnitude when the block size increased to 0.06 km(2), then gradually slowed down, and tended toward a plateau when the block size increased beyond 0.20. Therefore, the dynamic process can be divided into three phrases with multiple critical thresholds of block size. These are approximately 0.06, 0.08, and 0.20 km(2) ranked from the best to worst. The study indicates that block size has a nonlinear and threshold effect on urban vitality by constraining the maximum urban vitality. In general, the positive effect of small block size over urban vitality was confirmed, and additionally, urban planners should propose urban planning schemes with smaller residential blocks below 0.06 km(2).

我国的社区规划从20年前的零星行动到现在的全面开花,逐渐成为城市精细化治理的重要手段,呼唤更加系统完善和更为适宜的社区规划理论.文章从治理视角的社区规划、社区规划与城市规划的关系、社区规划的整体性、社区规划的在地性和社区规划的交叉学科属性5个方面认识我国新发展阶段社区规划的时代特征,提出空间创生、技术赋能、制度创新是当前和未来一个历史时期社区规划的核心要义,并在此基础上构建我国新发展阶段社区规划的实施路径.

New outlying development zones are a common phenomenon in the development of Chinese cities, and exploring their development level is a matter of great interest. Using geographic big data that cover the entire country, this paper analyzes the urban development level (UDL) of newly added outlying patches within 275 cities at the prefecture level or above in China from 2005 to 2015. The results revealed the following. 1) High-value cities are primarily located in the east, whereas low-value cities are primarily located in the west. The Beijing-Tianjin-Hebei urban agglomeration (BTHUA) is a major area with low UDLs, whereas the Yangtze River Delta urban agglomeration (YRDUA) and the Pearl River Delta urban agglomeration (PRDUA) are major areas with high UDLs. 2) The results of a multivariate regression demonstrate that GDP per capita (GDPPC), average elevation (AE), the distance between the new outlying urban patches, the proportion of secondary industry in GDP (PSI), the average land price in the city (ALP), the original urban land areas (DIS), and economic balance (GDPSD) significantly affect the UDL values of these cities. Relatively higher GDPPC and ALP are associated with a significant increase in the UDL, while more AE, DIS, GDPSD and PSI will decrease the UDL. The results of this paper provide a reference to understand the conditions of outlying developmental zones in China over the past 10 years as well as to explore healthy and reasonable urban spatial expansion forms.

当前我国老年人整体健康状况不容乐观,社区作为老年人日常活动的主要场所,其规划与设计对于老年健康具有重要意义.如何制定有效的社区建成环境改善策略成为政府决策者及规划师面临的关键问题,而厘清环境与健康之间的关系是解决该问题的基础.自2002年世界卫生组织发布《积极老龄化政策框架》以来,老年健康环境成为全世界、尤其是发达国家的关注热点,发表在国际主流期刊的研究日渐丰富.因此,本文对相关话题的国际研究进行回顾和总结,构建以体力活动和社区凝聚力为中介变量的"环境—健康"作用机制,梳理广泛应用的社区建成环境和老年健康结果评价指标及数据来源,分类解释和提炼实证研究结论,并结合中国实际对学术前沿热点问题进行展望,以期为老年友好的社区规划与建设提供理论参考和实践指导.

The emergence of geographical 'big data' provides new opportunities for studying urban issues. This study uses geographical 'big data' on point of interest density (POID), degree of urban function mixing (MIX), location check-in density (CIQD), housing prices (HP), and population change (POPC) to measure the urban vitality of patches of new development that occurred in Chinese cities from 2005 to 2015. The study uses association rule analysis to explore the relationship between different urban growth patterns on urban vitality, and the results indicate that different forms of urban growth have different effects on urban vitality. Infilling is characterized by high values for point of interest density and location check-in density with low values for urban function mixing and mixed values for population change. Edge-expansion is associated with high values for population change and urban function mixtures. Outlying expansion is associated with several negative values for urban vitality, particularly variables related to interactions between people and the environment around them (CIQD). The results indicate that cities may utilize these different forms of urban growth patterns to achieve different goals; for example, infilling may be more effective for office-style development in areas with existing higher population density and urban function mixtures, and edge-expansion may be effective for rapidly absorbing large populations and hosting urban functions that require larger footprints. As such, Chinese cities currently undergoing early stages of development should pursue high-intensity edge-expansion development. To the best of the authors' knowledge, this is the first attempt to study the relationship between urban expansion types and urban vitality through the use of 'big data,' and the results of this study can provide guidance on urban spatial development for government leaders and researchers in the future.

Air pollution in China is a serious problem and an inevitable threat to human health. This study evaluated the relationship between air quality and urban growth pattern in China by conducting empirical research involving 338 prefecture-level and above cities. Spatial regression techniques considering spatial autocorrelation were applied to correct the calculation bias. To obtain local and accurate results, a conception of eight economic zones was adopted to delineate cities into different groups and to estimate regression separately. An additional six urban form and socioeconomic indicators served as controlling variables. Significant and positive relationships between the aggregated urban growth pattern index and air pollution were observed in Northeast China, northern coastal China, and Northwest China, indicating that a high degree of urban aggregation is associated with poor air quality. However, a negative parameter was obtained in southern coastal China, showing an opposite association on urban aggregation and air quality. Nonsignificant connections among the other four zones were found. The findings also highlighted that land use mix, population density, and city size exerted varied and significant influence on air quality across eight economic zones. Overall, this study indicated that understanding the quantitative relationships between urban forms and air quality can provide policymakers with alternative ways to improve air quality in rapidly developing China.

The relationship between polycentric urban form and urban commuting has been widely debated in Western academic circles. However, qualitative and quantitative studies have not reached a unified conclusion. The evolution of urban form in China is remarkably different from that of developed Western countries. Many Chinese cities have begun using polycentric structures as their future development strategies. This study quantitatively measures whether polycentric urban form can improve commuting efficiency in China by using traditional statistics and emerging geographic big data. We use the polycentric index (PI) as the dependent variable and the congestion delay index (CDI) and mean traffic speed (MTS) as the main independent variables. Control variables include urban morphological space compactness (CT), number of private cars per thousand people (PC), number of buses per thousand (PB), urban road area per capita (PUA) and urban population density (PD). Regression models are employed to detect the relationships among the variables. The main research conclusions are as follows: (1) A high degree of PI results in low CDI and fast MTS; (2) a compact spatial form increases the impact of polycentricity on commuting efficiency; (3) maturity road infrastructure is an important measure to promote urban commuting under a polycentric urban form; and (4) the order of effect magnitude of polycentricity on MTS is PD > PC > CT > PUA > PB; on CDI, PD > PC > PB > CT > PUA. The results can be used in examining whether the current polycentric urban pattern planning in China’s cities can effectively improve commuting efficiency. They also provide a reference for the healthy development of China’s urban space and policy formulation of subsequent urban planning.

Given the rapidly developing processes in the housing market of China, the significant regional difference in housing prices has become a serious issue that requires a further understanding of the underlying mechanisms. Most of the extant regression models are standard global modeling techniques that do not take spatial non-stationarity into consideration, thereby making them unable to reflect the spatial nature of the data and introducing significant bias into the prediction results. In this study, the geographically weighted regression model (GWR) was applied to examine the local association between housing price and its potential determinants, which were selected in view of the housing supply and demand in 338 cities across mainland China. Non-stationary relationships were obtained, and such observation could be summarized as follows: (1) the associations between land price and housing price are all significant and positive yet having different magnitudes; (2) the relationship between supplied amount of residential land and housing price is not statistically significant for 272 of the 338 cities, thereby indicating that the adjustment of supplied land has a slight effect on housing price for most cities; and (3) the significance, direction, and magnitude of the relationships between the other three factors (i.e., urbanization rate, average wage of urban employees, proportion of renters) and housing price vary across the 338 cities. Based on these findings, this paper discusses some key issues relating to the spatial variations, combined with local economic conditions and suggests housing regulation policies that could facilitate the sustainable development of the Chinese housing market.

在旧城改造中,推行"微循环模式",不仅能延续城市空间形态,而且能减少地方政府的投资,吸引社会资金的投入,从而保证项目的推进与实施.该文以成都"北改"中的平福水巷街区为研究对象,以其微循环改造的更新规划与实施过程为研究内容,探讨在旧城改造中如何推行"微循环模式".

Because of limited conditions, way of removing old buildings then rebuilding by large area was difficult to carry out in northern Chengdu renovation district, so had to explore the new old city renovation mode dominated by urban regeneration. Taking Simaqiao district as an example and combining its historical date and investigation, finally urban regeneration strategies are put forward from four aspects, including teasing urban tissue & building urban axis, optimizing the space structure & extending the space form, leveraging economic leverages of urban regeneration and persueing tiny cycle renovation mode.

在阐明构建社区园林绿化及其水环境评价指标背景和必要性基础上,构建出该套评价指标体系的评价因子,并结合德尔菲专家调查法和层次分析法得出评价因子指标层、主题层、分目标层、总目标层的权重系数,最终得到一套完整的社区园林绿化及其水环境的评价指标体系。然后将该体系应用于成都市青羊区的6个典型社区,计算出各指标得分和综合得分,并根据结果分析其存在的问题,提出改进的建议。