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It aims to improve the construction of ecological civilization and promote the common development of urban and ecology. Firstly, contemporary ecological ethics is explored, and its principles and characteristics are summarized. Then, the technique of convolutional neural network (CNN) image in a deep learning model is analyzed. Finally, deep convolutional neural networks (DCNN) are used to analyze and model the spatial characteristics of contemporary cities based on ecological ethics. According to the investigations, rural residential areas are more consistent with ecological ethics than urban residential areas when compared with the ecological characteristics of farmland and forest, and the highest ecological eigenvalues of the two areas are about 8 and 6. In the analysis of urban space, the maximum value of ecological eigenvalues of an airport is 9, and that of a stadium is 8. However, the scope of their construction that is consistent with ecological ethics is very small. Moreover, the eigenvalues of ecological ethics in the urban business circle of casinos are not only very low (the highest values are about 5 and 3), but also consistent with the construction norms of ecological ethics. The work of urban spatial philosophy is optimized based on the adoption of the DCNN model of deep learning in ecological ethics, which not only provides the reference for future ecological urban planning but also contributes to the common development of urban and ecology. [ABSTRACT FROM AUTHOR]

Urban trees and forests provide multiple ecosystem services for urban dwellers. However, forest water use for these benefits has become one of the critical concerns in dryland regions where water is limited. Negative forest water use impacts could be reduced by selecting tree species with low rates of transpiration. However, the possible changes of urban tree transpiration and its biophysical controls are still unclear. This study monitored the sap flow of a 58‐year‐old Chinese pine (Pinus tabulaeformis) plantation in a semiarid urban environment of northern China. Soil moisture played an important role in stand transpiration (Ec). Ec had a strong positive relationship with vapour pressure deficit (VPD) and solar radiation (Rs) when soil water was sufficient. In addition, the sensitivity of leaf stomata to VPD was not related to leaf and branch water potential. Under soil water stress, Ec was significantly reduced by 63.1% (p < 0.001) and was weakly related to VPD and Rs. Canopy conductance (gc) was reduced (p < 0.001) by 74.3% due to leaf stomatal closure, and the sensitivity of leaf stomata to VPD was significantly increased (p < 0.05) with increasing leaf and branch water potential. Wind speed had no significant effects on Ec. P. tabulaeformis tended to be isohydric with a relatively constant midday leaf water potential (i.e. −2.46 to −2.92 MPa) and strong stomatal regulation as a function of soil water stress. However, slopes (0.53–0.56) of the linear relationship between m (dgc/dlnVPD) and reference canopy conductance were significantly lower than the widely recognized 0.6 (p < 0.001). Therefore, urban tree transpiration drivers and forest impacts need to be clarified to better understand the proper tradeoff between water consumption and ecological services for urban areas. [ABSTRACT FROM AUTHOR]

This paper considers how the (de)territorialised appeal of international schools in China can reflect, enforce and expand pre-existing patterns of urban segregation. Whilst exploration of the effects of educational marketplaces on urban environments has become a focus of scholarly research, the recent expansion in the supply of, and demand for, international education has caused these effects to become more nuanced. As (de)territorialised entities, international schools can cause multiple forms of spatial and psycho-social distinction and (dis)association to become intertwined, the effects of which start from the school and radiate out from there. International schools can therefore cause segregation to become a structurally entrenched phenomenon. These ideas are illustrated through an empirical examination of three international schools located in the eastern Chinese city of Suzhou. We explore the ways in which these schools are branded spaces that reproduce socio-spatial boundaries and thus foster a (de)territorialised sense of inter-belonging amongst their students. [ABSTRACT FROM AUTHOR]

Developing low-carbon logistics requires an understanding of the driving factors for carbon emissions. We employed the Comparative Study on Urban Transport and the Environment (CUTE) framework to identify the driving factors of China's logistics carbon emissions. Then, the Generalized Fisher Index Decomposition (GFID) model was adopted to decompose the effects of the driving factors. Finally, we tracked the spatial dynamics trajectory of each driving effect based on the gravity model. Our results showed that technical intensity and transport structure promoted carbon emissions, while technical efficiency and agglomeration curbed carbon emissions. The gravity centers of transport structure and technical efficiency converged with that of carbon emissions, whereas the gravity centers of technical intensity and industry agglomeration diverged from that of carbon emissions. The driving effects showed an obvious spatial heterogeneity, which indicated that carbon reduction policies should be formulated according to the local situation. [ABSTRACT FROM AUTHOR]

It is widely recognized that crimes are clustered in space. Features of the built environment are among various factors associated with crime clustering patterns. There are two competing perspectives on this association: the "encounter" and "enclosure" hypotheses. This study examines the effect of the built environment on the spatial distribution of residential burglary in Wuhan, China, aiming to test these two competing perspectives. First, we review existing studies analyzing the influence of the built environment on residential burglary, especially those based on the two hypotheses. We then conduct an exploratory data analysis to observe the spatial and temporal distribution patterns of residential burglaries. Next, we use a multivariate spatial regression model to evaluate the influence of various built environment characteristics on residential burglaries, after controlling for socio-demographic variables, guardianship, and the time-of-day effect. The results suggest a double peak in the hourly distribution of burglaries: 6:00 a.m.–8:59 a.m. and 5:00 p.m.–7:59 p.m. Burglaries are positively and significantly autocorrelated in space and mainly concentrated in the north-west and central areas of Wuhan. Two transport facilities features (intersection density and the presence of subway stations), three building features (multiple stories, high housing prices, and older houses), and land-use mix are each positively correlated with burglary. However, the burglary count is negatively correlated with the ratio of the residential land. Overall, neighborhoods with high permeability are vulnerable to residential burglaries. Thus, the principle of access control promoted by the enclosure hypothesis appears effective in preventing residential crime. The results' implications for crime prevention and urban design practice are also discussed. [ABSTRACT FROM AUTHOR]

How to utilize the shadows of buildings and greening to jointly improve the thermal cycle of the commercial pedestrian streets in hot and humid areas in southern China is a problem that needs to be discussed. This paper put forward related concepts of the invalid shadow area, valid shadow area, and thermal regulation within valid shaded areas, and designed a model for green planting of commercial pedestrian streets. By learning from relevant standards like ISO7243 and GB/T17244-1998, the paper used methods to measure the WBGT index, and selected two streets of different orientations in Qilou district in Haikou to measure changes in the WBGT index with and without solar radiation. The measurement results provided data for us to determine the time and scope of appearance of the valid shadow area, and thus define the planting area of commercial pedestrian streets Last, this paper conducted simulation analysis on the planting area using Envi-met4. The results indicated that the WBGT index of streets with plants was lower than that of streets without plants (by 1.49℃), and thus plants could provide relief in overheated commercial pedestrian streets. [ABSTRACT FROM AUTHOR]

Black carbon (BC) reduces the photolysis coefficient by absorbing solar radiation, thereby affecting the concentration of ozone (O3) near the ground. The influence of BC on O3 has thus received much attention. In this study, Mie scattering and the tropospheric Ultraviolet and Visible radiation model are used to analyze the effect of BC optical properties on radiation. Combined with data of O3 precursors in Nanjing in 2014, an EKMA curve is drawn, and the variations in O3 concentration are further investigated using a zero-dimensional box mechanism model (NCAR MM). When O3 precursors are unchanged, radiation and O3 show a highly similar tendency in response to changing BC optical properties (R=0.997). With the increase of modal radius, the attenuation of fresh BC to radiation and O3 first trends upward before decreasing. In the mixing process, the attenuation of BC to radiation and O3 presents an upward tendency with the increase of relative humidity but decreases rapidly before increasing slowly with increasing thickness of coating. In addition, mass concentration is another major factor. When the BC to PM2.5 ratio increases to 5% in Nanjing, the radiation decreases by approximately 0.13%–3.71% while O3 decreases by approximately 8.13%–13.11%. The radiative effect of BC not only reduces O3 concentration but also changes the EKMA curve. Compared with the NOx control area, radiation has a significant influence on the VOCs control area. When aerosol optical depth (AOD) increases by 17.15%, the NOx to VOCs ratio decreases by 8.27%, and part of the original NOx control area is transferred to the VOCs control area. [ABSTRACT FROM AUTHOR]

Background: Dengue fever (DF) is a mosquito-borne infectious disease that has threatened tropical and subtropical regions in recent decades. An early and targeted warning of a dengue epidemic is important for vector control. Current studies have primarily determined weather conditions to be the main factor for dengue forecasting, thereby neglecting that environmental suitability for mosquito breeding is also an important factor, especially in fine-grained intra-urban settings. Considering that street-view images are promising for depicting physical environments, this study proposes a framework for facilitating fine-grained intra-urban dengue forecasting by integrating the urban environments measured from street-view images. Methods: The dengue epidemic that occurred in 167 townships of Guangzhou City, China, between 2015 and 2019 was taken as a study case. First, feature vectors of street-view images acquired inside each township were extracted by a pre-trained convolutional neural network, and then aggregated as an environmental feature vector of the township. Thus, townships with similar physical settings would exhibit similar environmental features. Second, the environmental feature vector is combined with commonly used features (e.g., temperature, rainfall, and past case count) as inputs to machine-learning models for weekly dengue forecasting. Results: The performance of machine-learning forecasting models (i.e., MLP and SVM) integrated with and without environmental features were compared. This indicates that models integrating environmental features can identify high-risk urban units across the city more precisely than those using common features alone. In addition, the top 30% of high-risk townships predicted by our proposed methods can capture approximately 50–60% of dengue cases across the city. Conclusions: Incorporating local environments measured from street view images is effective in facilitating fine-grained intra-urban dengue forecasting, which is beneficial for conducting spatially precise dengue prevention and control. [ABSTRACT FROM AUTHOR]

This article critically examines the role of edutainment – the combination of educational and entertainment activities – in intangible heritage preservation. Drawing upon fieldwork in southwest China's Guizhou province, the article focuses on a cultural park that packages traditional ethnic practices into cultural products and leisure experiences for public participation and display. I consider this site as an example of a new form of hybrid cultural venue that shares similarities with earlier models of theme parks and museums, but also differs from them in important ways. This article discusses the potentials and the limitations of using interactive and experiential elements for facilitating the dynamic safeguarding of intangible heritage in creative urban environments. I argue that edutainment offers new learning opportunities to a public audience and to younger generations, but it inevitably entails transformations of traditional cultural forms and practices. Edutainment, in this context, becomes a strategic tool to preserve traditional skills and knowledge while promoting local cultures. [ABSTRACT FROM AUTHOR]

Palladium (Pd) is widely used in the production of automotive catalytic converters that serve to reduce toxic emissions from motor vehicles. The aim of this study was to explore the transport of Pd in the urban water environment. The results showed that the amounts of transported Pd in the pollution chain followed the order of rainfall runoff > estuary > receiving water body > wet deposition, indicating that rainfall runoff was the main source of Pd input. The amount of transported Pd might not depend entirely on the short-term Pd inputs from rainfall runoff and wet deposition. In the estuary, the phenomenon that Pd transport was dominated by suspended matter appeared for the first time in the entire pollution chain. Acertain amount of the inputted Pd was absorbed and accumulated in the urban water environment so that the inputted Pd was not completely outputted. [ABSTRACT FROM AUTHOR]

Responding to claims in urban studies and epidemiology that modern urban living negatively affects the mental health of the poor and newcomers to the city, this paper offers a different account based on an ethnography of a neighbourhood in central Shanghai, where precarious rural migrant lives unfold. Drawing on the concept of "ecologies of experience" to recognise the making of everyday sensibilities and affective tensions in urban dwelling, it focuses on subjectivity formed in habits of negotiating the urban environment, in coping with troubled thoughts and feelings posed by precariousness. The paper considers ecologies of experience arising in distinct prosaic locations – a public library, a large bookstore, and a café – found to be important in the everyday spatial practices of migrants, grounding to different degrees of success hopes for their present and future in the city. In such dwelling, the stresses to mental health – consistently described by migrants as "pressure" (yali) – seem to be moderated through varied forms of respite, slowing‐down, and "moments of being," though always in ambivalent ways. In recognising the everyday materiality of urban living, the paper looks beyond the tendency in studies of China's internal migration to read off migrant mental health outcomes from structural disadvantages related to work, welfare, and living conditions. Conceptually, it opens new ground in thinking by acknowledging the role of the felt qualities of lived experience in managing mental states, building on work in geography, sociology, and anthropology attentive to the affective resonances of place and to practices of urban negotiation. Focusing on migrant lives in central Shanghai, this paper examines how situated practices of urban dwelling contribute to the management of mental stress. Dissenting with accounts that typify urban living as deleterious to mental health, the paper argues that it is in the relationship between bodies and their environment where subjectivity, including mental states, are formed. [ABSTRACT FROM AUTHOR]

In many densely populated urban areas, artificial lakes have replaced natural river systems as water sources to provide people with water for living and industrial production. However, groundwater mounding due to seepage from water storage facilities will have an impact on the regional groundwater flow regime. This study investigated the effects of the construction and operation of the Doumen Reservoir in northwestern China on the local groundwater flow regime. Groundwater level variations before the construction of the impoundment were analyzed by wavelet analysis and indicated that most of the observed variations in levels were due to changes in groundwater abstraction in the area. Data were collected from drilling and real-time monitoring; a coupled Hydrus-1D and MODFLOW model was developed to simulate the impact of water storage on the surrounding groundwater environment. The simulation results show that compared with the initial flow field, the maximum elevation of the groundwater mound that would develop beneath water storage structured in the area would vary between about 4.9 and 6.9 m. Compared with the impoundment of the test section, other modeled scenarios will cause varying degrees of groundwater mounding around the reservoir area but no flooding of existing infrastructure is predicted to take place. The predicted seepage rate from the facility is 3660 m3/day, and anti-seepage measures are recommended to limit the effects of groundwater mounding. [ABSTRACT FROM AUTHOR]

As the forerunner and policy test field of the sustainable development, the sustainable development pilot zones are an important strategy for China to explore the mechanism and model of the coordinated development of human and land in different regional units. However, the impact of sustainable development pilot zones, especially on the improvement of environmental efficiency, needs to be assessed. In this paper, 187 prefecture-level cities in China were taken as samples (22 sustainable development pilot zones and 165 nonpilot ones). Firstly, the environmental efficiency of 187 prefecture-level cities between 2006 and 2016 was measured by data envelopment analysis (DEA). Then, the effect of construction of sustainable development pilot zones on environmental efficiency was assessed using the difference-in-difference (DID) model. The assessment results were further verified by propensity score matching with difference-in-difference (PSM-DID). In addition, the impact mechanism of construction of the sustainable development pilot zones on the environmental efficiency was discussed. Results show that the environmental efficiency of sustainable development pilot zones is 27.7∼31.7% greater than that of nonsustainable one, which is mainly attributed to the environmental regulation and industrial structure adjustment. [ABSTRACT FROM AUTHOR]

Resource-dependent cities (RCs) are a vulnerable group of urban settlements that often face population shrinkage; however, population changes in RCs in China are not well understood. This study offers new insight into this matter through a robust analysis that features a longer time scale, a larger sample of RCs, and a finer unit of analysis. It finds new evidence that problems of population shrinkage in RCs are more serious than previous literature has suggested. Approximately 30% of the studied units have experienced either long-term or short-term population shrinkage, and many more are experiencing a slowing down of population growth. Problems are especially common among three types of RCs: the resource-depleted RCs, the forestry-based RCs, and RCs in Northeast China. These results underscore transition policy inadequacies in addressing population loss, and call for a more comprehensive and diversified population policy that tackles the multifaceted factors that contribute to population shrinkage, including lack of industrial support, maladjustment to market oriented reformation, poor urban environment and natural population decline. [ABSTRACT FROM AUTHOR]

People are increasingly exposed to electromagnetic radiation with the rapid development of technologies such as broadcasting and mobile communication system. There is a concern that long-term exposure at low levels may be associated with various non-specific physical symptoms and ecological effects on animals and plants. It is extremely important to measure and analyze the electromagnetic radiation levels in order to protect people from the possible effects of electromagnetic radiation. A large-scale assessment of the effects of electromagnetic radiation on health or on ecology requires the ambient electromagnetic radiation levels over areas too vast to cover with conventional measurement methods. In this article, detailed information about the measurement tools and measurement method are given. The electromagnetic radiation exposure levels were measured on the main streets in the dense urban areas of Beijing, the capital of China. We apply ordinary kriging as an interpolation technique to assess the electromagnetic radiation exposure in large outdoor areas based on car-mounted measurements along the surrounding roads. The electromagnetic radiation exposure levels for larger areas can be investigated visually on the electromagnetic pollution map, which can assist decision makers by identifying the hotspots. [ABSTRACT FROM AUTHOR]

In this study, field measurements on the indoor living environments of elderly people were conducted to assess residential forms, heating methods, physical parameters, and thermal sensations in five urban and ten rural houses in Heilongjiang Province, China, in January 2017. The results indicated that urban houses used regional centralized heating systems in all the functional rooms, whereas rural houses used decentralized heating systems in only bedrooms and kitchens. Rural houses were less airtight than urban houses. Urban houses had continuous centralized heating and, thus, were warmer with steadier indoor temperatures than rural houses with decentralized heating. Additionally, the elderly in rural areas frequently encountered large temperature differences (weekly average = 28.9°C) between the indoors and outdoors, due to the outdoor toilet location. The daily amplitude of indoor temperature variations experienced by rural elderly was 8.0°C, which was 2.2°C higher than experienced by urban elderly. Moreover, most rural elderly did not express discomfort for indoor thermal environments despite living in colder rooms, since they wore thicker clothing and had lower comfort expectations. In addition, the rural elderly indicated strong adaptability to lower temperatures as suggested by their predicted mean vote, which was significantly lower than the thermal sensation vote. [ABSTRACT FROM AUTHOR]

• The concept of NC to study urban expansion was used. • A novel model, namely the TE FP model. • The TE FP model was used to evaluate the influence of the thermal environment. • A new perspective for studying the thermal environment was proposed. The change in the urban thermal environment resulting from urban expansion is attracting increasing attention from researchers. In this research, the influence of the urban expansion process on the spatial heterogeneity of the thermal environment was analyzed, including quantitative research on urban expansion based on the natural city (NC) concept using open data and the footprint of the thermal environment (TE FP) model to reveal the influences in different time periods between 2014 and 2018 in Guangzhou, China. And the TE FP is an indication used to evaluate whether certain area is affected by the thermal environment of the NC. The results demonstrated the following. (1) The high-temperature area in Guangzhou was 2293.55 km2 in 2014, 2330.24 km2 in 2016, and 2609.81 km2 in 2018 and expanded by 1.60% (2014–2016), 12.00% (2016–2018) and 13.79% (2014–2018), respectively. (2) The urban area increased from 182.10 km2 in 2014 to 266.90 km2 in 2018, which represented an increase by almost half, with an average annual expansion rate of 10.03%. (3) In 2014, 2016 and 2018, the area representing the TE FP consisted of the areas of five buffer zones, six buffer zones and eight buffer zones, respectively. This study provides a new approach to the study of urban expansion and a new perspective for exploring the influence of the urban expansion process on the spatial heterogeneity of the thermal environment. [ABSTRACT FROM AUTHOR]

There is now recognition that a population’s overall level of well-being is defined not just by income and wealth. Where we live and who we interact with are likely to be equally important in our overall levels of satisfaction with our lives. This thinking has stimulated studies of subjective well-being, or happiness, at both national and local scales. These studies suggest that where you live does matter, although it is health and family status that have the most direct effects on well-being. In this study, we use a detailed dataset on well-being from the China Household Finance Survey to reexamine well-being across China, where profound socioeconomic changes are taking place. The study controls for self-reported health and examines subjective well-being across extensive and varied Chinese urban and rural environments. We find that the earlier pessimism about China’s well-being, which emphasized declining happiness, may be misplaced. We make two contributions: first, we show a rising level of subjective well-being, and second, we show that there is a narrowing gap in well-being across different social indicators. Methodologically, we bring in the perspectives of both social capital and geographic context. [ABSTRACT FROM AUTHOR]

Rapid economic growth in China over the past 30 years has resulted in significant increases in the concentrations of small particulates (PM 2.5) over the city of Beijing. In addition to health problems, high aerosol loading can impact visibility and thus reduce photolysis rates over the city, leading to potential implications for photochemistry. Photolysis rates are highly sensitive not only to the vertical distribution of aerosols but also to their composition, as this can impact how the incoming solar radiation is scattered or absorbed. This study, for the first time, uses aerosol composition measurements and lidar optical depth to drive the Fast-JX photolysis scheme and quantify the photochemical impacts of different aerosol species during the Air Pollution and Human Health (APHH) measurement campaigns in Beijing in November–December 2016 and May–June 2017. This work demonstrates that severe haze pollution events (PM 2.5 > 75 µg m -3) occur during both winter and summer, leading to reductions in O3 photolysis rates of 27 %–34 % (greatest in winter) and reductions in NO2 photolysis of 40 %–66 % (greatest in summer) at the surface. It also shows that in spite of much lower PM 2.5 concentrations in the summer months, the absolute changes in photolysis rates are larger for both O3 and NO2. In the winter, absorbing species such as black carbon dominate the photolysis response to aerosols, leading to mean reductions in J [O 1 D] and J [ NO2 ] in the lowest 1 km of 24 % and 23 %, respectively. In contrast, in the summer, scattering aerosol such as organic matter dominate the response, leading to mean decreases of 2 %–3 % at the surface and increases of 8 %–10 % at higher altitudes (3–4 km). During these haze events in both campaigns, the influence of aerosol on photolysis rates dominates over that from clouds. These large impacts on photochemistry can have significant implications for concentrations of important atmospheric oxidants such as the hydroxyl radical. Idealized photochemical box model studies show that such large impacts on photochemistry could lead to a 12 % reduction in surface O3 (3 % for OH) due to haze pollution. This highlights that PM 2.5 mitigation strategies could have important implications for the oxidation capacity of the atmosphere both at the surface and in the free troposphere. [ABSTRACT FROM AUTHOR]

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This paper examines the effect of spatial structure, as measured on the monocentricity–polycentricity dimension, on labour productivity at the prefectural level in China. Using pooled cross-sectional and instrumental variable techniques, we find that, all else being equal, prefectures with a more monocentric spatial structure have a higher labour productivity, robust to different specifications. Furthermore, large agglomeration economies may fuel the beneficial effects of monocentricity. We conclude that, in terms of economic performance, monocentric-oriented spatial strategy could be a better choice for Chinese prefecture-scale regions. [ABSTRACT FROM AUTHOR]

Abstract Currently, some established urban indicator systems have been used in China to evaluate the sustainability performance of a whole urban system. However, the implementation of these systems is costly and time-consuming. A quick assessment for comparing and evaluating the trends of the sustainability performance of the urban built environment to support decision making of urban managers may be needed. Furthermore, this quick assessment can produce a general idea of sustainability profile for the urban built environment, which creates a foundation for further research and planning for improvements by employing more effective measures. This study provides such a quick assessment method using four large-sized Chinese cities as case studies. All data required for the evaluation is derived from official and publicly available statistic yearbooks. The method can supply an initial understanding and a deep impression of the sustainability performance of urban built environment. It also can be used to compare the sustainable performances of cities and at different periods of time. Highlights • The aim of this research is to propose a quick assessment for the urban built environment based on a sole data source, i.e. the China Statistic Yearbooks published by the national or a city's statistical bureau annually. • The application of this quick assessment to the four Chinese cities indicates that it is able to provide a snapshot sustainability evaluation of the urban built environment and identify the strengths and weakness of cities year by year. [ABSTRACT FROM AUTHOR]

Context: Accurately quantifying changes in urban greenspace (UG) is the prerequisite for understanding ecosystem service. In addition to quantifying the "real" change of UG, it's crucial to evaluate the change in quality of UG that is associated with quantitative change in area. Objectives: (1) Present a new index, dynamic index of UG (UGDI) that measures changes of UG by quantifying the loss and gain on UG simultaneously in a 100 m × 100 m grid cell. (2) Examine changes in the quality of UG measured by the NDVI. Methods: We focused on nine Chinese major cities, and used 2.5 m resolution ALOS and SPOT image data collected in 2005 and 2010, respectively, and 30 m Landsat TM data. Results: (1) By simultaneously quantifying the loss and gain, UGDI can identify the areas with dramatic turn over on vegetation cover that otherwise would not be able to be revealed by net change, or gain and loss alone. (2) Areas with low vegetation cover tended to increase in percent cover, and had larger magnitudes of UGDI. In contrast, the area with high vegetation cover generally experienced reduction in percent cover. (3) The NDVI value of newly-created greenspace in all nine cities was lower than that of lost greenspace, suggesting that adding the same amount of new greenspace might not compensate the loss of greenspace due to the difference in quality. Conclusions: Results can enhance our understanding on dynamics of urban greenspace, and provide insights for UG planning and management to improve urban environment and sustainability. [ABSTRACT FROM AUTHOR]

The washed and unwashed current (C) and previous year (C + 1) needles, branches and top soils of Pinus tabulaeformis trees were sampled at five sites Haitai industrial district (HT), Puji River (PJ), Fukang road (FK), Residential area (RA) and Baxian Mountain (BX) in Tianjin along an urban-rural gradient and analyzed for heavy metals (Cu, Mn, Zn, Pb and Cd) concentrations via ICP. C + 1 needles generally had higher Mn, Pb, Cd than C needles while the opposite was for Cu and Zn. Total Cu, Zn, Pb, Cd in soils peaked at HT and decreased at RA and BX. Heavy metals were generally higher in the unwashed needles than the washed needles at all sites. Meanwhile MDA, soluble sugar and free proline concentration in needles were increased with the increasing of heavy metal contents along the urban-rural gradient, further correlated with the heavy metal contents. [ABSTRACT FROM AUTHOR]

The rapid development of urbanization has had a dramatic impact on the ecological environment in China. In this paper, we first measure the urban eco-efficiency of 281 prefecture-level cities in China during 2006–2013 using the super-efficiency data envelopment analysis (SEDEA) model. We then propose a new comprehensive index system to assess urbanization. Finally, we quantitatively explore the relationship between urbanization and urban eco-efficiency based on a spatial econometric analysis. The results showed that China's average urban eco-efficiency and comprehensive level of urbanization of 281 prefecture-level cities had shown increase during 2006–2013. However, distinct spatial disparities exist among different cities. China's urbanization has significant characteristics of spatial agglomeration and spatial convergence during 2006–2013, with a high-to-low spatial distribution from eastern China to western China. Spatial effects play an important role in the changes of urban eco-efficiency in China through spatial spillover effects and regional replication and competition. Evidence from spatial econometric analysis reveals that an N-shaped relationship exists between urbanization and urban eco-efficiency, indicating that with the improvement of urbanization, urban eco-efficiency first increases, then declines and then increases again. The improvement of the level of technology and the formulation of effective environmental policies will promote the increase in urban eco-efficiency. The results provide significant references for urban ecological management and sustainable urban transformation in China. [ABSTRACT FROM AUTHOR]

The availability of remote sensing images of various resolutions has enabled the incorporation of landscape structures in land-cover mapping. Despite the effectiveness of landscape metrics in quantifying landscape structures, they are inadequate in characterizing three elements: spatial neighborhoods, spatial dependencies, and semantic dependencies. Moreover, methods for mining the regularity of landscape-structure heterogeneity (i.e., spatial variations in landscape structures) are still limited, particularly for applications in urban land-cover mapping. This study hence proposes a novel approach with the aims to (1) characterize landscape structures considering the above three elements; (2) mine the regularity of landscape-structure heterogeneity; and (3) apply landscape-structure information as contexts to improve urban land-cover mapping. To achieve the first aim, landscape-structure features including pair-wise spatial relationships and neighborhood-based landscape metrics are defined. To accomplish the second aim, a clustering technique and a landscape infographic are used to cluster landscape structures and visualize landscape-structure types, respectively. Finally, a hierarchical classifier based on the feedforward multi-layer perceptron is developed for the third aim. Experiments are conducted in a heterogeneous urban environment in Beijing, China. The results show that the proposed approach, which considers 34 landscape-structure features and 19 landscape-structure types, achieves a classification accuracy improvement of 6.43% compared with the approaches without considering landscape-structure information. This study therefore demonstrates the effectiveness of incorporating landscape-structure features and landscape-structure types in improving urban land-cover mapping. [ABSTRACT FROM AUTHOR]

This paper presents an empirical analysis of regional disparities from 2000 to 2012 based on a time series of data involving 74 cities within three mega-urban regions along Yangtze River in China. Differing from previous researches on inter-provincial and coastal/interior data, this paper provides a new perspective of mega-urban regions and their cities in China. By Coefficient of Variation and Analysis of Variance the selection of three mega-urban regions along Yangtze River reveals how the mega-urban regional disparities evolve among the east, middle and west up to date in China. In terms of general trend the mega-urban regional inequalities have been decreasing ever since the year around 2005. By traditional regression modeling this paper relates the mega-urban regional inequality and the alleviation to the urbanization and its focus on mega-urban regional development. The regression shows that the evolution of intra mega-urban regions disparities is negatively influenced by the urbanization with meaningful statistical significance from 2000 to 2012. The multilevel regression is further applied based on the nested hierarchical data structure. The results indicate a complicated relationship of the urban population density of the city level, the urbanization ratio of the mega-urban region level and the urban disparities in 2012. Finally limitations and further research advice are provided. [ABSTRACT FROM AUTHOR]

Urban ecological risk characterization is the final step in risk assessment and an important foundation upon which risk managers build risk aversion, risk control, and emergency handling strategies. In this study, we reviewed present risk characterization methods and proposed a multi-level characterization method for the assessment of urban ecological risks. The new characterization method consists of four elements: urban ecological risk sources, risk source probabilities, assessment endpoint indicators, and assessment endpoint indicator probabilities. Using this method, results of risk assessments can be organized into different levels of detail to meet different risk management goals. [ABSTRACT FROM AUTHOR]

Urban ecological risks stemming from urbanization are increasing and limiting the capability of China to effectuate sustainable urban development. Therefore, addressing urban ecological risks is an urgent need. Numerous factors are involved in urban ecological risks, including air, water, and soil. Additionally, risk sources and risk receptors are complex and diverse. In this study, urban ecological risks are defined as adverse effects and possibility of impacts on urban ecosystem services resulting from urbanization. Urbanization is recognized as the risk source, and the urban ecosystem is considered the risk receptor. Based on this understanding, the components of urban ecological risks are defined, and the relationships between the components of urban ecological risks are illuminated by establishing an indicator system. Based on previous studies on urban ecological risks, an explicit framework for identification, assessment, and management of urban ecological risks is proposed. For purposes of identification, there are three types of risk sources: population growth, industrial development, and the expansion of built land. Stressors include the accumulation of contaminants, consumption of resources, and occupation of space. Assessment endpoints are divided into provisioning, regulating, cultural, and supporting services. In response to urban ecological risks having multiple stressors and multiple assessment endpoints, we assessed risks both with a single stressor/single endpoint and comprehensive ecological risks. In our framework, the physical or material assessment of ecosystem services is adopted as the core method for the analysis of urban ecological risk, because it is believed that the analysis of urban ecological risk should be based on the physical or material assessment of ecosystem services instead of the value assessment of ecosystem services. The results of the single value assessment of urban ecosystem services will cause the deviation from the purpose of urban ecosystem services assessment. The purpose of urban ecosystem services assessment is to maintain and/or improve the capability of urban ecosystems of providing physical or material services, and further to reduce or avoid the occurrence risks of unsustainable cities. Additionally, a multi-level characterization method was adopted for the results of urban ecological risk assessment. In this study, we established a platform to manage urban ecological risks based on landscape ecology and environmental internet of things technologies, and to effectuate online urban ecological risk identification, assessment, and management via this platform. [ABSTRACT FROM AUTHOR]

Few studies have analyzed the health effects of temperature variability (TV) accounting for both interday and intraday variations in ambient temperature. In this study, TV was defined as the standard deviations of the daily minimum and maximum temperature during different exposure days. Distributed lag non-linear Poisson regression model was used to examine the city-specific effect of TV on mortality in 31 Chinese municipalities and provincial capital cities. The national estimate was pooled through a meta-analysis based on the restricted maximum likelihood estimation. To assess effect modification on TV-mortality association by individual characteristics, stratified analyses were further fitted. Potential effect modification by city characteristics was performed through a meta-regression analysis. In total, 259 million permanent residents and 4,481,090 non-accidental deaths were covered in this study. The effect estimates of TV on mortality were generally increased by longer exposure days. A 1 °C increase in TV at 0–7 days' exposure was associated with a 0.60% (95% CI: 0.25–0.94%), 0.65% (0.24–1.05%), 0.82% (0.29–1.36%), 0.86% (0.42–1.31%), 0.98% (0.57–1.39%) and 0.54% (−0.11-1.20%) increase in non-accidental, cardiovascular, IHD, stroke, respiratory and COPD mortalities, respectively. Those with lower levels of educational attainment were significantly susceptible to TV. Cities with dense population, higher mean temperatures, and relative humidity and lower diurnal temperature ranges also had higher mortality risks caused by TV. This study demonstrated that TV had considerable health effects. An early warning system to alert residents about large temperature variations is recommended, which may have a significant impact on the community awareness and public health. [ABSTRACT FROM AUTHOR]

The regenerative design framework aims to ‘engage a broader range of possibilities by moving beyond the immediate building and site boundaries’. It implies that the environmental performance of buildings requires a revised definition so that it considers not only the building itself, but also its contribution beyond its own boundary, i.e. neighbourhoods. In high-density cities, outdoor spaces are culturally considered as the extension of one’s living spaces. The environmental performance of neighbourhoods is particularly important to the health and wellbeing of urban inhabitants. This paper aims to define the environmental performance of neighbourhoods in high-density urban context based on the experience acquired in previous studies in Hong Kong over the last 15 years. These studies cover a wide range of environmental issues including urban climate, outdoor thermal comfort, and daylighting design in high-density cities. Subsequent development of the assessment tools for environmental performance of neighbourhoods in Hong Kong is also presented. The framework of stakeholder engagement, as an integral part of the neighbourhood assessment tool, is discussed. This paper highlights the distinctive features of the environmental performance of neighbourhoods in high-density urban context and how it influences the professional practices in Hong Kong. [ABSTRACT FROM AUTHOR]

Nitrous acid (HONO) is a key reservoir of the hydroxyl radical (OH) and plays a central role in the atmospheric chemistry. To understand the sources and impact of HONO in the polluted atmosphere of northern China, continuous measurements of HONO and related parameters were conducted from September 2015 to August 2016 at an urban site in Ji'nan, the capital city of Shandong province. HONO showed well-defined seasonal and diurnal variation patterns with clear wintertime and nighttime concentration peaks. Elevated HONO concentrations (e.g., over 5 ppbv) were frequently observed with a maximum value of 8.36 ppbv. The HONO/NO X ratios of direct vehicle emissions varied in the range of 0.29%–0.87%, with a mean value of 0.53%. An average NO 2 -to-HONO nighttime conversion frequency (k het ) was derived to be 0.0068 ± 0.0045 h −1 from 107 HONO formation cases. A detailed HONO budget analysis suggests an unexplained daytime missing source of 2.95 ppb h −1 in summer, which is about seven times larger than the homogeneous reaction of NO with OH. The effect of HONO on OH production was also quantified. HONO photolysis was the uppermost source of local OH radical throughout the daytime. This study provides the year-round continuous record of ambient HONO in the North China Plain, and offers some insights into the characteristics, sources and impacts of HONO in the polluted atmospheres of China. [ABSTRACT FROM AUTHOR]

China's aging population is growing rapidly. To date, there have been few literatures concerning indoor environment of private houses with older people. This study fully investigated indoor environment in 10 houses (5 urban and 5 rural houses) with older people during heating season in Beijing, China. Each house was assessed for temperature, relative humidity, CO 2 , PM 2.5 , CO, NO x , formaldehydes, acetaldehyde, VOCs, SVOCs and fungi. Results indicated older people in urban houses experienced a steadier and warmer thermal environment than those in rural houses, due to the difference of heating devices between urban and rural houses. Indoor CO 2 levels mainly increased up to 1000 ppm in the bedroom during sleeping time. For rural houses, indoor fuel combustion contributed to an extremely high PM 2.5 and CO level. Formaldehyde, acetaldehyde, toluene, ethylbenzene and xylenes levels in most houses were lower than the limit values. However, the integrated influence of these compounds was unnegligible. TVOC concentrations in four measured houses exceeded the reference value of 600 µg/m 3 . The most frequent fungi was Cladosporium spp. (90%), followed by Penicillium spp . (70%) and Aspergillus spp. (60%). The fungal levels in rural houses were higher than urban houses. These results will be beneficial to improve housing environmental quality for older people in China. [ABSTRACT FROM AUTHOR]

Urban ecosystem is plagued with complexities and uncertainties due to the interconnections among multiple subsystems, as well as human and environment interventions. In this study, a hybrid AHP-FMADM method through coupling fuzzy multiple attribute decision-making (FMADM) with analytic hierarchy process (AHP) is developed to evaluate urban ecological security (UES). AHP-FMADM has advantages in (i) reflecting interactive relationships among multiple attributes in UES, (ii) dealing with uncertainties expressed as imprecise linguistic terms and judgments, and (iii) achieving the ranking of alternatives based on pairwise comparison. Then, AHP-FMADM is applied to assessing the ecological security of Guangzhou from 2005 to 2015, where an urban ecological security evaluation indicator system is constructed based on the pressure–state–response conceptual model. A number of scenarios with different weight assignment modes are examined. Results indicate that the overall ecological security of the study city is gradually improved. Urban environment indicators contributes more to the ecological security level than social and economic indicators. However, although ecological security state and response level increase significantly, the ecological pressure has increased since 2012, which may result in a decline of ecological security. Compared to the traditional fuzzy synthetic analysis (FSA) approach with weighted sum operator, AHP-FMADM cannot only reduce the effect of the attributes with low importance and increase that with high importance, but also help decision makers determine alternative adaptation options and management schemes based on their preferences. These findings reveal that indicators with high importance degree need to be efficiently adjusted for decision makers to maintain ecological security, such as increase water reuse ratio and control the rapid growth of the population. [ABSTRACT FROM AUTHOR]

This study looks into one of the most promising low carbon city planning initiatives in China, namely Shenzhen's International Low Carbon City (ILCC). First as a collaborative project between the Dutch and Chinese partners, the ILCC's international partners have expanded to include other countries, such as Germany, Italy, France, Australia and the US. This paper investigates the influence of these international actors in the development process of the ILCC and their benefits in the long run, through knowledge transfer and accumulation of resource. The paper first highlights a broad understanding of ‘low carbon city’ followed by detailed discussions on discourses of ‘low carbon city’, ‘eco-city’, and ‘low carbon eco-city’ in China. Then it provides insights on knowledge transfer in low carbon city development, and particularly the Sino-Foreign cases of China. The authors then introduce the case of study (ILCC) and highlight its visions, project planning, and partnerships. Using primary and secondary data, it then maps the ILCC's international actors and their roles, and then analyses their behaviours and impacts in the project's planning and development process. Next, the paper summarises the research findings with further updates on the case of ILCC. The authors conclude that the engagement between Chinese and international partners differ in three forms and they are (1) the type of involvement; (2) the level and timeframe of involvement; (3) the level of Influence in the project's multiple stages. The paper concludes that the role played by an international partner evolves as the project proceeds. [ABSTRACT FROM AUTHOR]

This paper reports the results of a car-following measurement of the wireless propagation channel at 5.9 GHz on a seriously congested urban road in Wuhan, China. The small-scale amplitude-fading distribution was determined to be a Ricean distribution using the Akaike information criterion. This result shows that this car-following scenario can be regarded as a line-of-sight radio channel. Moreover, the statistical K-factor features follow a Gaussian distribution. According to the power delay profile and average power delay profile, we found that street buildings in this dense urban environment contributed to very strong reflection phenomena. The impact of a powerful reflection is analyzed through path loss, delay, and Doppler spreads in the channel statistical properties. In the frequency domain, we observe a U-shape delay-Doppler spectrum that proved that the dense urban scenario consists of scattering channels. All these results are summarized in tabular form that will be useful in the modeling of vehicle-to-vehicle wireless communication systems. [ABSTRACT FROM AUTHOR]

Seven organophosphorus compounds (OPs) were measured in urban fine and coarse particulate matter (PM) collected from two sites of Nanjing (XCNUC), China and Islamabad (APHSP), Pakistan. The fine PM mass at APHSP site was significantly higher (p = 0.005) in the spring (mean 22.5 μg/m 3 ) than in the summer (mean 12.7 μg/m 3 ). The total concentration, ∑ 7 OPs, of samples collected at APHSP was found significantly higher in coarse (range 672–47621 pg/m 3 ) than in fine PM (range 1200–15213 pg/m 3 ); while ∑ 7 OPs from XCNUC in fine (range 1696–15063 pg/m 3 ) and coarse PM (range 2053–5379 pg/m 3 ) were statistically different in samples during summer, based on two-sample t -test at 0.05 confidence interval. Seasonally, ∑ 7 OPs was found to be higher in the samples of Nanjing (9510 ± 3633 pg/m 3 ) in the summer than in the spring. In contrast, the samples of Islamabad had higher ∑ 7 OPs (25558 ± 16255 pg/m 3 ) in the spring than in the summer. Tri(chloropropyl) phosphate (TCEP) was found at higher concentration than any other OPs in the samples from the XCNUC site. Triphenyl phosphate (TPhP) was found at extremely high levels from APHSP, which may attributed to its use in jet fuel. Most of the ∑OPs concentrations were found significantly different in both PMs at both sites due to their diverse sources. Both sites showed strong correlation of ∑OPs with TCEP in both PMs, indicating similar mode of transfer from sources like plastics, lacquer, paint, glue, industrial processes and foam fillers. Relative abundance of OPs in fine and coarse PM differs amongst OP congeners and concerning seasons, with these variations attributed to different mechanisms of mass transfer such as volatilization, condensation and abrasions. Moreover, triphenylphosphine oxide (TPPO) has been reported in outdoor PMs. This is the first study on the occurrence of OPs in atmospheric fine and coarse PM and their seasonal variation from Pakistan and China. [ABSTRACT FROM AUTHOR]

As one of the important parts of urban ecosystem, urban green space plays an irreplaceable role in maintaining the balance of carbon and oxygen, absorbing the pollution and removing dust, killing bacteria, purifying soil and water. To analyze the spatio-temporal changes of humidifying effect of green lands at the spring daytime, the authors monitored the air humidity within 1.8 m high from various underlying surfaces, including arbor-grass lands, shrub lands, herb lands and a cement pavement, from late February to late April in 2015 and 2016, when it was sunny and windless, in the Yuxi park of Shijazhuang. The results were compared with the monitoring data of a bare land (190 m × 120 m) without environmental interventions such as vegetation and water. The results could be summarized as follows: ① The humidifying effect of green spaces was the weakest at 8:00 a.m. during the late February, whereas it was the strongest at 10:00 a.m.; from late March to late April, the humidifying effect of green spaces strengthened with the increase of air temperature, and the strongest was noted around 12:00-16:00. ②The humidifying effect of various types of green lands was the strongest close to the ground, and reduced from 0.2 m to 1.8 m. This vertical stratification became apparent after the plants sprouted, the vertical difference of humidifying effect was the most significant in the herb lands, less significant in arbor-grass lands, and least in the shrub lands. ③ Multiple comparison analysis of the humidity data showed that relative humidity of all green lands achieved the significant level (P < 0.05), indicating the strong effect of landscape plants in adjusting atmospheric humidity in spring. ④The humidifying effect of the artificial lake was more remarkable before the plants sprouted, however, with the rapid growth of plant leaves, the effect gradually reduced and became even weaker than the effect of vegetation. Although the humidifying effect in spring was weaker than that in summer and autumn, the effect of humidification was more complicated during the growth of green leaves in spring than in summer and autumn. This is useful to construct the theory system of ecological environment effect of green lands in spring, summer and autumn. [ABSTRACT FROM AUTHOR]

Cities are currently confronted with many urban problems, such as water shortages, water quality pollution, floods, and the loss of habitats of aquatic organisms, and badly in need of a more comprehensive solution. In this context, the concept of "sponge city" is proposed. This paper, based on the theory of sponge city and low impact development, elaborated the origin, development, connotation, and construction method of "sponge city" concept. In this paper, the urban design scheme of Renbei District in Chengdu was taken for example to analyze the geographical environment and climate characteristics of Chengdu and explain the formation and verification of the scheme. It is considered that the "sponge city" is different from the traditional urban infrastructure. It is essentially an ecological approach. It's core is to build a cross-scale urban water ecological infrastructure to comprehensively solve the prominent water-related problems of urban and rural areas in China. [ABSTRACT FROM AUTHOR]

The analysis of the service range and optimized layout of urban parkland through scientific methods is conducive to urban ecological environment, urban fabric and stable order to provide accessible recreational places for residents. 'This paper took Jianghan District in Wuhan for example, based on the GIS network analysis and vector databases of road network, park and population, to obtain the irregular service range of different types of park and bearing capacity. The results showed that the service range of daily recreation within 20 min accounted fur 75.5% of the total area, and the bearing capacity of Lingjiaohu Park, Wangjiadun Park, and Longwangmiao Park was low. It was thus concluded that there were visible blind areas and invisible blind areas in Jianghan District. Therefore, specific optimized layout of parkland was implemented in different blind areas to effectively combine park green space and residents' recreational activities, so as to achieve reasonable layout of urban parkland. [ABSTRACT FROM AUTHOR]

To constrain sources of anthropogenic nitrogen (N) deposition is critical for effective reduction of reactive N emissions and better evaluation of N deposition effects. This study measured δ 15 N signatures of nitrate (NO 3 − ), ammonium (NH 4 + ) and total dissolved N (TDN) in precipitation at Guiyang, southwestern China and estimated contributions of dominant N sources using a Bayesian isotope mixing model. For NO 3 − , the contribution of non-fossil N oxides (NO x , mainly from biomass burning (24 ± 12%) and microbial N cycle (26 ± 5%)) equals that of fossil NO x , to which vehicle exhausts (31 ± 19%) contributed more than coal combustion (19 ± 9%). For NH 4 + , ammonia (NH 3 ) from volatilization sources (mainly animal wastes (22 ± 12%) and fertilizers (22 ± 10%)) contributed less than NH 3 from combustion sources (mainly biomass burning (17 ± 8%), vehicle exhausts (19 ± 11%) and coal combustions (19 ± 12%)). Dissolved organic N (DON) accounted for 41% in precipitation TDN deposition during the study period. Precipitation DON had higher δ 15 N values in cooler months (13.1‰) than in warmer months (−7.0‰), indicating the dominance of primary and secondary ON sources, respectively. These results newly underscored the importance of non-fossil NO x , fossil NH 3 and organic N in precipitation N inputs of urban environments. [ABSTRACT FROM AUTHOR]

Although microclimate effects of the urban fabric and the urban green are known, they are rarely considered in energy performance studies of buildings in their specific context. The microclimate in the urban environment is effective on human well-being and on the energy demand of buildings. Especially the temperatures surrounding buildings in summer and, in case these buildings are air conditioned, the resulting energy demand for cooling are effected. However microclimatic design strategies are evaluated (if at all) qualitatively or based on short periods of ‘representative conditions’, while thermal building simulation studies are usually performed with climate datasets from weather stations remote from the real urban context. This paper introduces and applies an algorithm to translate available EPW climate data into annual climate datasets containing urban microclimate effects of the specific location through multiple application of the microclimate simulation model ENVI-met. The resulting annual microclimate information is able to be applied in thermal simulation studies with TRNSYS to determine the course of the temperatures in a building over the year as well as the resulting annual cooling demand. 56 detailed 24h-simulation runs are performed to represent the climatic conditions each week of the year and four additional extreme climate situations. From the results of these ENVI-met calculations an 8760h-dataset is constructed as input for an annual thermal simulation study. The algorithm has been tested for 26 locations in China through comparison of the original dataset with a model representing a ‘neutral’ site environment for calibration. It then has been applied for urban context models with green coverage. Differences in maximum temperatures as well as the impact of the urban context on the annual cooling demand are reported for the 26 locations. From these results also the CO2-emission reduction potentials are calculated. [ABSTRACT FROM AUTHOR]

The complex urban environment has multiple levels of design and planning that are applied in the form of blocks, layouts and city patterns. This paper develops an analytical study based on urban residential blocks in Ningbo city in China. It explores issues of density, green infrastructures, and urban quality with particular focus on environmental performance. At what point does exaggerated density reduce both living qualities and opportunities for good climatic design and a low carbon footprint? The study applies a simple methodology to evaluate and compare planning options for residential areas. The goal is pragmatic, seeking not ideal solutions but realistic and inexpensive alternatives to current practice which is particularly inefficient in terms of energy and climate emissions. Some potential advantages of low-dense as compared to high-rise solutions are noted. The study highlights questions as to optimal or appropriate typologies and densities for sustainable cities, in particular in the fast expanding cities of developing countries. [ABSTRACT FROM AUTHOR]

Purpose The historical city of Macao has recently become one of the world’s centres for tourism and gaming. But growing traffic congestion in its narrow and old road network, especially in the city’s historic centre, raises concerns about the city’s traffic pollution, environmental impacts and negative effects on residents’ and visitors’ health. The purpose of this study is to address the possibility of mitigating emerging environmental problems with urban design solutions.Design/methodology/approach A review and background of the city’s evolution, from a Mediterranean-style town in the sixteenth century to its present status as one of the highest population density cities in the world, is first undertaken. The paper then critiques the urban layout that conditions current traffic and pollution trends.Findings High levels of pollution of particulate matters are created by a mixture of circumstances related to tall buildings along narrow roads, especially in the historic centre’s San Ma Lou Avenue, that limit ventilation and trap pollution. Green solutions that are known to effectively mitigate this problem, as well as contribute to enhancing the area’s carrying capacity, are discussed.Originality/value The originality of this paper lies in its critique of the environmental impact of rapid and overwhelming tourism-oriented development on the quality of the urban environment. It advocates urban design solutions based on experiences from other global tourist cities that, if implemented, will not damage the historic centre’s built environment and will contribute to a more liveable city for residents and better experience for visitors. [ABSTRACT FROM AUTHOR]

The China Healthy Cities initiative, a nationwide public health campaign, has been implemented for 25 years. As "Healthy China 2030" becomes the key national strategy for improving population health, this initiative is an important component. However, the effects of the initiative have not been well studied. This paper aims to explore its impact on urban environment using a multiple time series design. We adopted a stratified and systematic sampling method to choose 15 China healthy cities across the country. For the selected healthy cities, 1:1 matched non-healthy cities were selected as the comparison group. We collected longitudinal data from 5 years before cities achieved the healthy city title up to 2012. We used hierarchical models to calculate difference-in-differences estimates for examining the impact of the initiative. We found that the China Healthy Cities initiative was associated with increases in the proportion of urban domestic sewage treated (32 percentage points), the proportion of urban domestic garbage treated (30 percentage points), and the proportion of qualified farmers' markets (40 percentage points), all of which are statistically significant (P < 0.05). No significant change was found for increases in green coverage of urban built-up area (5 percentage points), green space per capita (2 square meter), and days with Air Quality Index/Air Pollution Index ≤ 100 (25 days). In conclusion, the China Healthy Cities initiative was associated with significant improved urban environment in terms of infrastructure construction, yet had little impact on green space and air quality. [ABSTRACT FROM AUTHOR]

Urban ecological infrastructure is the ecological background of urban sustainable development and is the basic guarantee for the construction of ecological cities. According to the characteristics of the ecological infrastructure of coal-based cities, the ecological infrastructure is divided into two subsystems: natural infrastructure subsystem and artificial infrastructure subsystem. According to each subsystem and its main components (such as atmosphere, green space, hydrology, traffic and transportation), 36 indicators were selected to establish the evaluation system In addition, the evaluation model was established by means of mean square deviation method and composite index method, and a dynamic analysis was carried out on the ecological infrastructure quality of Huainan Qty in 2006-2015. The results show that the composite index of ecological infrastructure in Huainan Qty in 2006-2015 remained at the medium level, and the natural infrastructure at the worse and poor levels, while the artificial infrastructure remained at the medium and excellent levels. [ABSTRACT FROM AUTHOR]