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Context: Expansion of urban green space (UGS) enhances greenery and its benefits in cities. However, the impacts of such expansions on regional landscape sustainability and their spatiotemporal traits across the national scale remain unclear. Objectives: This study uncovers a trade-off between agricultural ecosystem services and urban human well-being—the loss of grain production due to UGS expansion consuming cropland—in China from 2000 to 2020. It proposes a safety boundary for UGS expansion to minimize the costs of grain production while addressing the escalating demand for UGS exposure. Methods: UGS expansion and cropland loss are quantified using land cover products, with statistical data contributing to the established relationship between grain loss and UGS coverage. UGS expansion scenarios for 2040 are simulated through bottom-up modeling. Results: Quadrupled UGS area growth contributed approximately one-third to urban expansion during 2000–2020 in China. Despite improvements in per capita UGS area implying enhanced UGS exposure during rapid urbanization, UGS expansion resulted in a national grain production loss of 4.2 ± 1.4 million t from 2000 to 2020, accelerating post-2010. This loss is equivalent to the annual food intake of 9.3 million Chinese people. We propose a 30.87% UGS coverage target in China by 2040 to preserve UGS access while minimizing grain loss under future urbanization. Conclusions: Acknowledging the critical role of UGS expansion in the issue of cropland loss to urbanization is imperative. Our results offer insights into ensuring human well-being and ecosystem services through landscape and urban planning. [ABSTRACT FROM AUTHOR]

The development of China's high-density urbanisation process has made people aware of the widespread injustice in urban green space (UGS) as a means to improving residents' well-being. The Chinese National Forest City (NFCC) policy is one of China's construction models that aims to develop urban greening and reduce the inequality of residents' well-being. This study used a combination of qualitative research and index quantification to explore the relationship between the spatial distribution of NFCCs and the factors affecting inequality in green space allocation and their impacts. The results of the study show that changes in indicators in NFCC policy reflect the national government's decision-making orientation towards achieving environmental equity, and that the main factors affecting the unequal spatial distribution of NFCCs are highly correlated with inequality in UGS resources. This study analysed the NFCC policy from a new perspective and provides useful information for the development of national forest policy in order to ensure sufficient green space in China and the elimination of environmental inequity. [ABSTRACT FROM AUTHOR]

China is experiencing unprecedented urbanization and aging. Previous studies mostly ignored the internal mechanism of the effect of urban green space on the mental health of older adults. Consequently, the relationship between social participation in urban green spaces and mental health remains uncertain. Therefore, this study explored the impact of urban green spaces, social participation, and other factors on the mental health of older adults and investigated the mechanisms of these effects. This study used linear regression models and conducted a moderating effect analysis using data from the 2018 China Labor Dynamics Survey, comprising 3501 older adults in 146 cities in China. Furthermore, we analyzed differences between solitary and non-solitary older adults. The results indicated that urban green space, road density, physical health, history of hospitalization, subjective well-being, and economic satisfaction significantly affected mental health. Social participation played a significant positive moderating role in the connection between green spaces and mental health among older adults. For solitary older adults, social participation weakened the positive impact of green spaces on mental health; for non-solitary older adults, social participation enhanced the positive impact of green spaces on mental health. These findings could contribute to the future construction of aging-friendly cities in China and help optimize urban construction and strategies for building healthy environments. [ABSTRACT FROM AUTHOR]

The Sustainable Sites Initiative (SITES) is a comprehensive evaluation system for sustainable landscape, which has been promoted successfully and widely recognized in the landscape architecture industry. However, the existing research lacks attention to the applicability of SITES to urban green space construction projects in China. Therefore, exploring the application of the SITES evaluation system in the context of Chinese urban green space development is of great importance. Building upon theoretical research on sustainable landscapes, this study focuses on urban green space projects as the research carrier, with SITES as the subject of investigation. Utilizing the case study method, a thorough description and analysis of Xuhui Runway Park, a representative case officially certified by SITES in China, is provided. Across four stages—project initiation and planning, scheme design, construction, and operation—this study discusses the approaches employed in Chinese urban green space projects to meet the requirements of the SITES evaluation system. By evaluating the applicability of SITES to Chinese urban green space projects, identifying limitations in system promotion, and offering references for sustainable design practices, this study advances the application and promotion of SITES in China and contributes to the sustainable development of the landscape architecture industry. [ABSTRACT FROM AUTHOR]

Current cities are not concrete jungles and deserts with sparse vegetation. Urban green space (UGS) appears widely in human activity areas and plays an important role in improving the human living environment and accumulates carbon storage. However, given the scattered distribution of UGS, studies on both the refined spatial estimation of carbon storage and appropriate mapping scale are still lacking. Taking the downtown area of Kaifeng, China, as the study area, this study verified the i-Tree Eco model on the basis of a field survey and accurately estimated the spatial carbon storage of UGS by combining it with remote sensing data, and finally, we obtained the minimum spatial mapping scale of UGS carbon storage by scaling. The results showed that (1) the total area of UGS in study area was 26.41 km2, of which the proportion of total area of residential area and park green spaces was about 50%. The area of UGS per capita in the study area is 40.49 m2. (2) Within the 123 survey samples, the proportion of communities with tree–shrub–herbs structure was the highest, 51.22%. The average carbon density was 5.89 kg m−2, among which the park, protective and square green spaces had the highest carbon density in all land use types. (3) The total carbon storage of UGS in the study area was 114,389.17 t, and the carbon storage of UGS per capita was 175.39 kg. Furthermore, the scaling analysis showed that 0.25 km spatial resolution was the minimum spatial scale for UGS carbon storage mapping. This study improves our understanding of urban carbon storage, highlights the role and potential of UGS in carbon neutrality, and clarifies the importance of estimating urban carbon storage at appropriate scales. This study is also of great significance for rationally understanding the terrestrial carbon cycle in urban areas and improving regional climate simulations. [ABSTRACT FROM AUTHOR]

Background: Continuous increasing carbon dioxide (CO2) has aggravated global warming and promoted urban tree planting projects for many countries. So it's imperative to select high carbon sequestering landscape tree species while considering their aesthetic values of urban green space. Results: 32 tree species were selected as test objects which were commonly used in landscaping in Zhengzhou, a typical northern city of China. To assess the comprehensive carbon sequestration potential of landscape tree species in different plant configuration types, we simultaneously considered their daily net carbon sequestration per unit leaf area (wCO2), daily net carbon sequestration per unit land area (WCO2) and daily net carbon sequestration of the whole plant (QCO2) through cluster analysis. Besides that, we found out the key factors affecting carbon sequestration potential of landscape tree species by redundancy analysis. Conclusion: Populus, P Stenoptera, P. acerifolia among large arbors (LA), V odoratissimum, P. Serratifolia, S. oblata among small arbors (SA), and B sinica var. Parvifolia, B. Megistophylla, L quihoui among shrubs (S) were recommended for local urban green space management. Photosynthetic rate (Pn), crown area (CA) and leaf area index (LAI) were the key factors which affected the comprehensive carbon sequestration potential both for LA, SA and S. [ABSTRACT FROM AUTHOR]

As population growth and urbanization continue to accelerate, city dwellers are increasingly conscious of the demand for urban green space (UGS) and the ecosystem services (ESs) it provides. Great efforts are made for the supply of certain ESs in UGS. However, less is known about the residents' preferences and the supply–demand matching of UGS types, as well as the various ESs it provides at different spatial scales. Given this, our research establishes a research framework to reveal the heterogeneity of USG types and the supply–demand matching degree (SDM) of ESs from municipal, provincial, and national spatial scales, and examines the correlation between the influencing factors and demands of residents for UGS. This study mainly used the Gini coefficient, the Lorenz curve, Z-scores, the Jenks natural breaks classification method, Pearson correlation analysis, and spatial analysis. The main findings are that (1) the Gini coefficients are 0.433 and 0.137 at the municipal and provincial scales, respectively, indicating that the supply of UGS is more unequal at the municipal scale than provincial scale; (2) the multi-scale demand for ESs between residents has no significant difference. At the provincial scale, the area with low demand is larger than that of high demand, while at the municipal scale, the contrary is the case; (3) the SDM was in a deficit at both the provincial and municipal scales. And as the scaling-up occurred, the spatial heterogeneity of the SDM decreased; (4) the number of influencing factors that significantly affected the UGS type and ESs grew as the scale increased. Among them, the impact of age and COVID-19 on three scales deserves attention. These results identify regions with deficits and surpluses in ESs provided by UGS in China at different scales. This research also advises that attention should be paid to the distribution of UGS between cities within provinces, and future UGS planning should focus on building regional green spaces to promote the well-being of an aging society. The findings in this study would offer insights for managers to improve UGS construction and urban forestry planning in the future. [ABSTRACT FROM AUTHOR]

The provision of urban green space is spatially uneven, which has brought challenges in shaping the inequalities of people's subjective well-being in the developing world. Using panel data of 37 typical cities in China from 2012 to 2017, this study analyzes links of urban green space and environmental satisfaction from urban residents. We divide effects of urban green space into direct parts including scale, coverage rate and accessibility of urban green space, and indirect parts including environmental and economic performance of urban green space, measured by the bootstrap-DEA model. The geographically and temporally weighted regression model is applied to evaluate links. We find that increasing accessibility of urban green space can significantly improve environmental satisfaction, and the economic performance of urban green space is significantly negative with environmental satisfaction. The results also show scale, coverage rate and environmental performance of urban green space insignificantly associated with environmental satisfaction. Additional results show the spatial and temporarily varying about the urban green space–environmental satisfaction relationship over time and space. This study provides empirical evidence for further optimizing the allocation of urban green space. [ABSTRACT FROM AUTHOR]

Stormwater resources are not effectively utilized in many Chinese cities, which not only wastes water resources but has also brought about serious urban flooding problems. Urban green space, as a resilient approach of stormwater regulation and storage, has been widely applied in urban flooding control and sponge city construction. Through a review on relevant literature in the past two decades, this paper systematically compares the methods commonly used in the assessment on stormwater regulation and storage capacity of urban green space, examines the pattern factors affecting the capacity, and expounds the application of urban green space in stormwater management at different scales. The literature review aims to provide a scientific basis for the alleviation of urban flooding problems and the construction of sponge cities. Meanwhile, the paper also puts forward four development trends in the research on the stormwater regulation and storage function of urban green space. [ABSTRACT FROM AUTHOR]

Studies have shown that disadvantaged neighborhoods have fewer green spaces, resources, and facilities, resulting in residents facing more barriers to using green spaces. This study aims to quantify green space usage patterns and constraints in old residential neighborhoods in a large city in northern China. A questionnaire survey and semi-structured interviews were conducted with 668 residents. Results showed that most residents visited their local green spaces daily, often in the evenings, and spent between 30 and 60 min there. The number of visits on weekends is higher than on weekdays, with no difference in visiting alone or in groups. The main reason for visiting green spaces was to relax and enjoy nature, followed by spending time with family. Limitations to usage included poor physical environments, such as inadequate facilities, lack of maintenance, overcrowding, poor accessibility, limited activities, and pet restrictions. This study provides insights into the current state of green space utilization in old residential neighborhoods, as well as a discussion of the limitations, which could inform future renovations and designs of green spaces in these areas. [ABSTRACT FROM AUTHOR]

With accelerated urbanization and rapid expansion of the urban population, there is an increasing demand among urban residents for urban green spaces (UGS) and the ecosystem services (ES) they provide. The existing research mostly focuses on the spatial pattern of UGS types and ES provided by different UGS but ignores that residents' preferences for UGS types and their ecological and social services should also be incorporated into the spatial planning decision-making of UGS. A web-based questionnaire was distributed randomly in urban areas of China and 1050 valid samples were collected in this study. Descriptive statistical analysis methods, structural equation modeling, and Pearson correlation were used to parse the residents' preference for both UGS types, ecological–social services, and the relevant impact factors. The results showed that: (1) the strongest preference of residents for UGS and their ecological and social services are the attached green space, "beautifying the city", and "physical and mental relaxation", respectively; (2) the leading factors for residents' access to UGS are "age" and "sufficient time", except for attached green space. The most significant effect on both ecological and social services is the "season" factor. Further, "social gathering" and "exercise" are the services most and least likely to be affected. (3) Future planning of UGS should reinforce construction of attached green space and improve the aesthetics-related ES they provide. Construction of park green space and plaza green space should be enhanced to deal with the aging trend in society. Further, maintaining the existing construction of attached green space and building regional green space are crucial to the sustainability of UGS and its ecological–social services. [ABSTRACT FROM AUTHOR]

• Despite the need to understand UGS preference across countries, few comparative studies exist. • Perceived accessibility is the main factor positively affecting the enjoyment of visiting parks on foot. • In the UK and China, for frequent park users, visit duration decreases with increasing visit frequency. • Unlike in China, enjoying scenery motivates more older individuals' visiting parks in the UK. The literature identifies an important research gap regarding the variability in people's needs and preferences for Urban Green Space (UGS) depending on sociodemographic and cultural backgrounds. Therefore, it is essential to understand the impact of these differences on UGS utilization preferences. However, there remains a lack of a comprehensive comparative research on this topic. This study compared the analysis of park usage and preferences from urban parks accessed on foot by analyzing and comparing the results of 2,360 online questionnaires from Guangzhou (China) with 7,159 responses from London (UK) using the Monitoring of Natural Environment Engagement (MENE) survey data. The results highlighted the importance of knowing which park usage and preferences were more likely to exhibit large variations/similarities based on different socio-demographic and cultural backgrounds. For example, one difference was in the UK older people were more likely to spend less time in parks, while in Guangzhou duration increased up to the age of 50 years before declining. One similarity indicated that park users in both countries tended to spend longer times in parks if they walked longer times accessing these parks. These findings have implications for distinguishing international planning and designing principles in various social cultural contexts. [ABSTRACT FROM AUTHOR]

• Mechanisms by which UGS's economic benefit affects social equity are further demonstrated. • Analyzing the economic benefit of UGS in the housing price market. • Examining the perceptual evaluation of UGS by different social stratification groups. • Revealing the green residential segregation under the UGS housing price divergence effect. • Testing the green space paradox in developing country. Urban green space (UGS) plays a crucial role in socio-ecological systems and has been recognized as an important factor in promoting sustainable cities and communities. Although a few studies have proposed a paradox of the incompatibility of economic benefit and social equity in UGS, the mechanisms through which the economic benefits of UGS interact with social equity have not been adequately demonstrated in developing countries. Here, we employ multi-source geographic information and 1559 residents survey data to investigate not only the economic benefit of UGS in the housing prices market from a macro perspective, but also the social inequity issues resulting from the housing choices of different social classes under "UGS economic benefit" from a micro perspective. Results reveal that the economic value premium of UGS in the housing market triggered a differentiation effect in housing prices, subsequently influencing housing preferences among various social classes, thus intensifying social residential segregation. This phenomenon underscores the emergence of the green space paradox. Moreover, the phenomenon of the UGS paradox has emerged in megacities of developing countries, where UGS is gradually being occupied by social elites, while vulnerable groups remain marginalized. These findings provide valuable insights into the planning layout of UGS in global high-density built-up areas that a small and decentralized UGS layout will be more economically efficient and socially equitable than a large and centralized UGS layout. [ABSTRACT FROM AUTHOR]

The hot and humid feeling of the urban environment enhances residents' discomfort indices. Although the cooling and humidifying effects of plant communities in various urban parks are significant, there is still insufficient evidence for the effects of plant community characteristics on temperature and humidity. In this study, 36 typical plant communities in the Changchun Water Culture and Ecological Park in China were selected in the summer (21–23 August 2020) from 8:00 to 18:00 for three days when it was sunny and windless. We obtained plant community characteristics through field measurements and drone recordings to explore the relationship between plant community characteristics and the mechanism of temperature and humidity. The study observed that (1) the canopy density and three-dimensional green amount were significantly related to the benefits of cooling and humidification. When the canopy density is between 0.7 and 0.8 and the three-dimensional green volume is above 4 m³/m², the greatest benefit is achieved; (2) the discomfort index is between 0.6 and 0.8, and the three-dimensional green volume is 4 m³/m²–6 m³/m² minimum; and (3) the changes in temperature and humidity are different for different types of plant communities, which lead to differences in people's perceptions of environmental comfort. The tree–grassland and tree–shrub–grass types had the most apparent improvement effects on comfort. The results show that in the design process of urban park plants, emphasis is placed on plant community configuration with apparent cooling and humidification effects, which can improve the comfort of tourists in hot and humid environments. The research results provide theoretical support for sustainable urban green space development. [ABSTRACT FROM AUTHOR]

The urbanization process has contributed to the deterioration of the urban thermal environment and increased the frequency of heat waves in summer that damage public health. Urban green space is the space for the public to escape the summer heat. The cooling effect of urban green space (UGS) can encourage outdoor activities and enhance public health. Analysis of when and how the public utilizes UGS under summer heat can serve as a guide for UGS improvements. In this study, the Hot Spring Park in Fuzhou City, China was utilized as a case study to examine the characteristics of the public recreational behaviors and their influencing factors under summer heat. Results showed the following observations: (1) Canopy density and turf coverage played key roles in regulating the thermal environment. (2) UGS can accommodate multiple summertime behaviors with considerable spatiotemporal variations. (3) In the hot summer, the frequency of recreational activities in UGS was negatively correlated with temperature. Dynamic behaviors were significantly impacted by temperature. Older and younger groups were less heat-tolerant. Based on this, we propose countermeasures and suggestions that are tailored to the needs of urban residents and their behavior characteristics for the planning and management of urban parks in the summer heat. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization, the urban heat island (UHI) effect has intensified. Urban green space can retard the UHI effect. However, most existing studies have only focused on hot regions, while little attention has been given to cold regions that also have summer heat protection requirements. Furthermore, existing researc has not classified urban green spaces according to the presence or absence of water, which can lead to inaccurate results. This paper takes four cities in cold regions of China as examples and studies the cooling effects of two different types of urban green space. The results indicate that in cold regions of China, green spaces containing water bodies have a stronger cooling effect than those without water. For green spaces without water, the cooling intensity is related to the background temperature and green space areas, while for green spaces containing water bodies, the area of the internal water body is the key influencing factor. Specifically, there is a threshold value of efficiency (TVoE) for the green space areas without water in cold region cities of China, which is approximately 0.52 ha, while there is no TVoE for the green space areas containing water bodies. Additionally, there is a TVoE for the water/land ratio of the green spaces containing water bodies of approximately 0.5. The methods and results of this study can provide a reference for future research and for urban planners and managers designing urban green spaces. [ABSTRACT FROM AUTHOR]

Urban green spaces are the soil component in cities that interacts most closely with humans. This study investigated the residues of seven neonicotinoids (NEOs) in soils from urban green spaces within the Pearl River Delta (PRD) region and analyzed the correlation between the residue characteristics and the region's economic development. Notably, we introduced the Nemerow Index method, a comprehensive approach, to quantify the overall pollution level of NEOs in the soil of urban park green spaces and utilized this to assess the cumulative exposure probability risks for different populations in this scenario. We found that: (1) The soil of urban park green spaces exhibited varying degrees of NEOs contamination (Σ 7 NEOs: N.D.-137.31; 6.25 μg/kg), with imidacloprid and clothianidin constituting the highest proportions (89.46 % and 83.60 %); (2) The residual levels of NEOs in Children's Park were significantly higher than those in community parks within Guangzhou, with an average value of 13.30 μg/kg compared to 3.30 μg/kg; (3) The residual characteristics of NEOs exhibited a positive correlation with regional economic development; specifically, the per capita GDP well correlated with IMI RPF , a summation of seven NEOs in imidacloprid equivalents via relative potency factors (R 2 =0.86). Regions with higher economic development typically exhibited elevated IMI RPF levels; (4) The fitted cumulative probability distributions for average daily exposure doses revealed that children's exposure was an order of magnitude higher than adults'. Despite this, the exposure risks for both groups remained within acceptable limits., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Introduction: The importance of improving older adults' mental health is increasing worldwide with the rapid development of the aging process. Green space is an important part of the urban built environment, demonstrates a deep connection with the mental health of older adults, and its internal mechanisms have been widely studied. This study analyzed the influence of urban green spaces on the mental health of older adults via three factors: relative deprivation, physical activity, and social trust., Methods: Based on the 2018 China Labor Dynamics Survey, a multi-level structural equation model was used to explore the mediating roles of relative deprivation, physical activity, social trust in urban green spaces, and the mental health of older adults., Results: Urban green space was positively correlated with the mental health of older adults. Relative deprivation and physical activities played a mediating role between urban green space and the mental health of older adults., Discussion: An increase in urban green spaces can help increase the number of older adults obtaining green space resources, and help them maintain good mental health. Secondly, older adults with a relatively homogeneous environment have more equal opportunities to obtain urban green space resources, which helps to reduce the comparison of older adults in access to green space resources and reduce the adverse impact of relative deprivation on their mental health. Additionally, increasing urban green spaces can encourage older adults to engage in physical activities and improve their mental health. Finally, we suggest improving the accessibility, fairness, and quality of green spaces, paying attention to the psychological needs of older adults, encouraging older adults to engage in physical activities in green spaces, and taking various measures to enhance the positive role of green space on the mental health of older adults., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zuo, Cheng, Feng and Zhuang.)

Long-term population loss and economic downturns have led to shrinking cities generally lacking social vitality and losing public spaces, such as green spaces. Previous studies have demonstrated the importance of green spaces for the social capital and health of residents, but the impacts of green space usage on health inequalities in the context of urban shrinkage have not been fully explored. In addition, residents who live in shrinking cities in northeastern China are more likely to suffer health problems due to their location in a severely cold region. Therefore, we selected 17 urban green spaces in Hegang, a typical shrinking city, as the research objects. We collected a total of 544 valid questionnaires through random distribution. These data were used to evaluate four green space usage characteristics of residents comprising transportation costs, usage frequency, usage duration, and participation in activities, as well as two social capital dimensions that are directly related to health comprising social networks and reciprocity and trust. We conducted correlation analysis, multivariate analysis of variance, and analysis of covariance to explore the impacts of green space usage on two categories of social capital for residents with different attributes and the consequences of health inequalities. The results showed that: (1) women, middle-aged and elderly people, and the low- and middle-income classes were less able to access social capital through the usage of green spaces; (2) the frequency of green space usage and intensity of participation in social activities were key dimensions that affected inequality; and (3) the usage of green spaces reinforced inequalities in the level of reciprocity and trust among residents. Based on our findings, we recommend that local governments in shrinking cities pay more attention to green spaces and squares in inner city areas to improve the accessibility and usability of these open spaces. Governments should focus on regenerating green spaces located near older neighborhoods to increase opportunities for residents to make new social connections and reduce inequalities in public services and health, especially for improving the social well-being of older populations with a lower socioeconomic status. • Green space usage may exacerbate health inequalities among residents. • Women, middle-aged and elderly people, and the low- and middle-income classes were less likely to access social capital. • The usage frequency and intensity of social activities were key dimensions that contributed to health inequalities. • It is necessary to increase the attractiveness to different groups of people and the likelihood of social interaction. • Local governments should focus on regenerating green spaces around disadvantaged communities. [ABSTRACT FROM AUTHOR]

Seasonality is a typical feature of landscapes in temperate regions. Seasonality's effects on visual aesthetic quality (VAQ) are widely recognised but not well understood. To address this gap, 10 sample sites were selected to represent the diversity of urban green spaces in Xuzhou, eastern China, which has a typical temperate monsoon climate. Photographs of the 10 sites were acquired in eight typical months to capture seasonality. Online surveys were used to evaluate the VAQ of the photographs. The mean value of the coefficient of variation of 16 landscape characteristics of a site during the seasons was used to represent seasonal diversity. The results indicated that: (1) the autumn landscape was the most preferred, and the winter landscape was the least preferred; (2) there was a significantly inverted U-shaped relationship between year-round VAQ and seasonal diversity. This is the first study to define seasonal diversity and its effect on VAQ. [ABSTRACT FROM AUTHOR]

Urban trees perform various ecosystem services, and tree DBH (trunk diameter at breast height, 1.3 m above the ground) can act as a surrogate measure of these important functions. However, DBH has seldom been studied in relation to spatial variation, possible underlying drivers, and response to urbanization. Our field investigation collected data from tree species within Urban Function Units (UFUs) in south China's coastal city Zhanjiang, which has recently experienced rapid urbanization. The land cover of UFUs was determined by visual interpretation of satellite images. Trees with DBH > 2 cm were assessed, and vines were excluded. We recorded 12,434 trees in the green space belonging to 185 species, 137 genera, and 51 families. The dominant DBH range, 5‒15 cm, accounted for 43.72% of the total stems. The DBH of 33 individuals exceeded 90 cm, 20 of which were Ficus species. At 32.39 cm, the average DBH in commercial areas was the highest among the UFU types, while woodlands had the lowest at 7.11 cm. GLMM analysis showed that UFU types, landscape configuration, land cover, and construction age were all significantly associated with tree DBH. Tree DBH had a significant positive correlation with impervious surface area and a negative correlation with green space surface area. The largest trees were mainly distributed in urban villages, schools, parks, and transportation areas. Understanding urban tree DBH structure and its related factors can promote sustainable urban-forest development and management. [ABSTRACT FROM AUTHOR]

High-quality urban green space (UGS) is an integral part of a livable city. The scientific evaluation of UGS has great value for improving the quality and efficiency of green spaces. In this study, we integrated the water and walking networks into the existing green index model and proposed a new green index: the building blue–green index (BBGI). Using this method, we analyzed the quality of green spaces within 300 m of 2138 buildings located in 13 communities in the Mochou Lake subdistrict in Nanjing, China. The results revealed that the green-space quality of high-rise, low-density buildings was greater than that of low-rise, high-density buildings. In addition, buildings close to water had higher green-space quality, while impervious surfaces reduced green-space quality. Furthermore, the connectivity and orientation of the road network indicated that even if a community was close to large parks and water bodies, there would still be lower green-space quality. This study's findings highlight the usefulness of evaluation methods for green-space quality that combine blue and green spaces. We also propose feasible measures for improving neighborhood green-space planning and land management. [ABSTRACT FROM AUTHOR]

Previous studies have identified barriers to investment in good quality urban parks during the planning and design stage, particularly noting the ineffectiveness of planning instruments, a low political will to invest in urban green spaces and constraints in governance operation. The factors that influence the quality of urban parks in the planning and design stages of investment were investigated through interviews with technical professionals who have acted as consultants to local government across China on urban planning and landscape projects. A set of thematic characteristics were identified as shaping the planning and design of good quality urban parks in China: the reliance on quantitative metrics in the contemporary planning context; the linkage between local political will to invest in urban parks, local leaders' prestige and local administrators' enthusiasm in governance operation; and local administrators' equipment with knowledge and effectiveness in communicating with technical professionals. [ABSTRACT FROM AUTHOR]

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Urban green spaces play a crucial role in cities by providing near-natural environments that greatly impacts the health of residents. However, these green spaces have recently been scrutinized as potential reservoirs of antibiotic resistance genes (ARGs), posing significant ecological risks. Despite this concern, our understanding of the distribution, sources, and ecological risks associated with ARGs remains limited. In this study, we investigated the spatial distribution of soil ARGs using spatial interpolation and auto-correlation analysis. To apportion the source of soil ARGs in urban green spaces of Tianjin, Geo-detector method (GDM) was employed. Furthermore, we evaluated the ecological risk posed by ARGs employing risk quotients (RQ). The results of our study showed a significantly higher abundance of Quinolone resistance genes in the soil of urban green spaces in Tianjin. These genes were mainly found in the northwest, central, and eastern regions of the city. Our investigation identified three main factors contributing to the presence of soil ARGs: antibiotic production, precipitation, livestock breeding, and hospital. The results of ecological risk in RQ value showed a high risk associated with Quinolone resistance genes, followed by Aminoglycoside, Tetracycline, Multidrug, MLSB, Beta Lactam, Sulfonamide, and Chloramphenicol. Mantel-test and correlation analysis revealed that the ecological risk of ARGs was greatly influenced by soil properties and heavy metals. This study provides a new perspective on source apportionment and the ecological risk assessment of soil ARGs in urban green spaces., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

During the process of urbanization, many green spaces are fragmented for other uses. The key problems for researchers and planners are reducing the fragmentation of green spaces, constructing urban ecological networks, and maintaining sustainable environments to cope with the rapid urbanization process. This paper analyzes Fuzhou, China as a case study of the effects of urbanization, and reviews three epochs in Fuzhou: 2000, 2010, and 2021. First, the integration degree of landscape pattern index and spatial syntactic attribute value is used to quantify the urbanization situation of Fuzhou and the degree of green space fragmentation in the process of urbanization. Second, it adopts the network analysis method to construct an urban ecological network featuring "one city and two rings". Finally, urban green spaces are assessed by the corridor structure analysis, and the improvement of the urban green space ecological network is quantitatively evaluated by comparing the green space ecological network with the green space planning system. The results show that the urbanization of Fuzhou city center is apparent and the fragmentation of urban green space is a serious issue from 2000 to 2021. The green space planning in Fuzhou is ineffective in improving the existing green space. According to the results, the street integration of space syntax aptly reflects the process of urbanization. In conclusion, the planned ecological network increases the shape complexity of green patches and landscape connectivity and reduces landscape fragmentation, thus improving the urban ecological environment quality and facilitating the sustainability of urban green spaces. [ABSTRACT FROM AUTHOR]

Despite that the heavy metals in urban soils pose a threat to public health, the critical factors that influence their concentrations in urban soils are not well understood. In this study, we conducted a survey of surface soil samples from urban green spaces in Shanghai, to analyze the concentrations of the key heavy metals. The results showed that Zn was the most abundant metal with an average concentration of 122.99 mg kg−1, followed by Pb (32.72 mg kg−1) and Cd (0.23 mg kg−1). All concentrations were found to be below the risk screening values defined by the National Environmental Quality Standards for soils of development land in China (GB36600-2018), indicating no current risk in Shanghai. However, there was a clear accumulation of heavy metals, as the mean concentrations were significantly higher than the background values. Furthermore, we explored the relationships between key heavy metals with population density, GDP and green space area. Both Spearman correlation and Random Forest analysis indicated that per capita green space area (pGSA) and population density were the most crucial factors influencing the status of heavy metals in urban soils, unlike edaphic factors e.g. SOM content in farmland soils. Specifically, there was a significantly positive linear correlation between heavy metal concentrations and population density, with correlation coefficients ranging from 0.3 to 0.4. However, the correlation with pGSA was found to be non-linear. The nonlinear regression analysis revealed threshold values between heavy metals concentrations and pGSA (e.g Zn 22.22 m2, Pb 24.92 m2, and Cd 25.92 m2), with a sharp reduction in heavy metal concentrations below the threshold and a slow reduction above the threshold. It suggests that an increase in per capita green space area can mitigate the accumulation of heavy metals caused by growing population density, but the effect is limited after the threshold. Our findings not only provide insights into the distribution patterns of heavy metals in the urban soils at the local scale, but also contribute to the urban greening at the global scale and offer guidance for city planning in the face of increasing population densities over the coming decades. [Display omitted] • All concentrations of heavy metals in the surveyed urban green spaces met safety standards. • Per capita green space area was a critical factor influencing heavy metal concentrations in urban soils. • Heavy metal concentrations were positively correlated with population density. • Increasing green space area mitigated heavy metal accumulation but had a marginal effect. [ABSTRACT FROM AUTHOR]

The accurate identification and monitoring of urban green space is of great significance in urban planning and ecological management. In view of the complex background of urban green space, the traditional remote sensing classification technology is prone to the problem of misalignment and adhesion. Taking Yuhua District of Changsha City as the research area and Gaofen-2 (GF-2) remote sensing image as the data source, we proposed a remote sensing classification method for urban green space based on the LA-UNet model, which was based on the UNet model. We introduced the DWTCA channel attention mechanism module to improve the attention of the network to green space information, and used the CARAFE module to up sample the extracted features to achieve accurate classification of trees, shrubs and other land types in the complex background of the city. The results showed that the LA-UNet model had the best classification effect of urban green space when using standard false color remote sensing images. The overall accuracy and mean intersection over union were 96.3% and 90.9%, which were 2.8% and 6.1% higher than the UNet model, respectively. In the Potsdam public dataset, the overall accuracy and mean intersection over union of the LA-UNet model were also better than those of the UNet model, which increased by 0.9% and 1.8%, respectively, indicating that the LA-UNet model had good robustness and versatility. In summary, the proposed LA-UNet model could effectively alleviate the problems of misalignment and adhesion of urban green space, with advantages in the remote sensing classification of urban green space. The improved LA-UNet model had a smaller parameter volume than the UNet model, which could effectively improve the classification accuracy of urban green space. This study would provide a methodological reference for the accurate classification and understanding the spatial distribution of urban green space.

Old industrial areas have low quality and spatial differentiation of urban green space (UGS), which makes it difficult to meet the public's physical activity needs and leads to increased health risks. The purpose of this study is to explore the equity of UGS patterns in old industrial areas and its internal relationship with residents' health status. This study selecteds relevant indicators to evaluate the equity of UGS patterns in the Harbin area and used linear regression analysis to explore the correlation between attributes of old industrial areas and UGS patterns. Additionally, this study explored the spatial correlation of UGSs using Moran's index and hotspot analysis. Finally, a report on residents' health was generated through a questionnaire survey, using linear regression analysis to explore the factors affecting residents' self-rated health and the significance of their correlation. The results showed that there is an excess supply around the core industrial zone in the west, while the rural areas in the south face a serious shortage of supply. The significance between the factors representing age and income in industrial attributes and UGS pattern was less than 0.05. We observed that residents' self-rated health was positively affected by the intensity of physical activity (low intensity B = 2.073, medium intensity B = 2.359, high intensity B = 2.512) and the frequency of physical activity (B = 1.174). Ages (B = −0.597) and three generations living together (B = −3.191), which represent the industrial attributes, had a negative impact on residents' self-rated health. To a certain extent, industrial attributes aggravate the mismatch of UGS patterns, leading to abnormal areas in spatial clustering. The quality of UGS in the old industrial zone is low and the movement is not strong; thus, the population characteristics and income have become the important factors affecting the health of residents. • According to the industrial attributes of the study area, the selected green space objects are all UGSs with physical activity conditions. • A new UGS supply and demand pattern index system is constructed to evaluate the fairness of UGS patterns in terms of physical activity. • There is a serious imbalance between supply and demand of UGS in old industrial areas. The stronger the industrial property, the more unbalanced the supply pattern of UGS. • Industrial attributes have profoundly affected the pattern matching and spatial aggregation of UGS supply and demand in old industrial areas. • Demographic characteristics and physical activity status had a significant effect on residents' health, while UGS patterns were not significantly affected by age, income, etc., regarding self-rated health. [ABSTRACT FROM AUTHOR]

• Application of multi-source data in accessibility indicator evaluation. • Multilevel search radius is adopted. • The inverse distance weighting method is used for indicator visualization. • Suggestions for urban renewal based on accessibility indicators. Rapid urbanization in China results in an uneven distribution of Urban Green Space (UGS) resources. This study aims to provide a scientific basis for optimizing the layout of UGS during the urban renewal process. This study takes Qingdao City Center of China as an example. Using the expanded model of Gaussian Two-Step Floating Catchment Area Method, different search thresholds are set based on the service scale and radius of UGS. This analysis delves into the distribution characteristics of UGS accessibility by walking. The results show that the accessibility of UGS in the Qingdao City Center presents an obvious circular structure, with Badaguan Block and Jinmen Block as the high-value core of accessibility that gradually decrease toward the periphery. There is a significant gap between the supply of UGS and the actual demand of the residential population, and 65.49% of residential quarters in Shinan District have lower accessibility of UGS than the average level of the whole district. According to the results of accessibility analysis, the optimization strategies and spatial intentions are proposed from three aspects: the renewal of existing spaces, the integration and utilization of resources, and the improvement of the UGS system. [ABSTRACT FROM AUTHOR]

Urban green space (UGS) is susceptible to shocks from multiple sources, including the economy and governance. It is now a global policy challenge to ensure the sustainability and livability of cities. Nevertheless, available studies have reached contradictory conclusions regarding the economic impact on UGS. Using statistical data, empirical studies in the Chinese context failed to differentiate between built-up areas and municipalities and neglected data matching within the study area. To address these gaps, this study explored the relationship between the economy and UGS at various quantiles by constructing unconditional quantile regression (UQR) models using panel data from 283 Chinese cities (2001–2019). The relationship between economic growth and the total area of UGS in the municipal zone (ugs_area) and UGS coverage of built-up areas (ugs_rate) was generally positive and statistically significant, according to the analysis. Furthermore, the study observed heterogeneity in the relationship between the economy and ugs_area and ugs_rate across different quantiles, indicating a growing presence of UGS appearing in the periphery of built-up areas. Cities strived to increase ugs_area and ugs_rate to meet the National Garden City (NGC) standards. After NGC designation, ugs_area and ugs_rate decreased significantly. Moreover, the positive correlation coefficient between the economy and UGS in provincial capital cities was considerably greater than in non-provincial capital cities. This study contributes to UGS research by revealing the nonlinear impact of driving factors. In addition to distinguishing between UGS in municipal districts and those specifically in built-up areas, this study quantifies the impact of governance variables. The study provides a valuable resource for planning UGS in China and promoting harmonious integration of economic growth, governance, and UGS in rapidly developing cities. [Display omitted] • We explored the effect of multiple factors in shaping the UGS. • This study includes panel data of 283 cities (2001–2019) using econometric methods. • Economic growth is pushing UGS to the urban fringe, despite benefiting UGS growth. • Economic impact on ugs_area is stronger in provincial capitals. • Upon designating as an NGC, the citie's ugs_area and ugs_rate significantly decline. [ABSTRACT FROM AUTHOR]

Objective: To date, a comprehensive analysis of urban green space (UGS) visitors' emotional remains largely unexplored. In this study, we focus on how UGS environmental preferences, restorativeness, other physical factors (sound, air, and thermal environments), and individual characteristics affecting visitor emotions. Such a comprehensive analysis would allow relevant practitioners to check the environmental quality of UGSs and improve certain conditions to promote visitor emotions., Methods: A total of 904 questionnaire responses with concurrently monitored physical factors were analyzed by independent sample t -tests, one-way ANOVA and path analysis., Results: The thermal evaluation had the largest impact on positive emotions (β = 0.474), followed by perceived restorativeness (β = 0.297), which had β values of -0.120 and -0.158, respectively, on negative emotions. Air evaluation was more effective for increasing positive emotions (β = 0.293) than reducing negative emotions (β = -0.115). Sound evaluation also had similar results (β = 0.330 vs. β = -0.080). Environmental preference significantly influenced only positive emotions (β = 0.181) but could still indirectly impact negative emotions. Moreover, objective physical factors can indirectly affect visitors' emotions by enhancing their evaluations.., Conclusion: The influence of different UGS environmental factors on visitors' emotions vary, as does their impacts on positive versus negative emotions. Positive emotions were generally more affected than negative emotions by UGS. Visitor emotions were mainly influenced by physical and psychological factors. Corresponding suggestions are proposed for UGS design and management in this study., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wu, Liu, Quevedo, Cheng, Yu and Kohsaka.)

Introduction: Exposure to green space can bring many benefits to physical and mental health, but in China, the attractiveness of green space to youth groups seems to be not significant. The question of how to encourage young people to go out of the house to better perceive green space, enjoy nature, and promote physical and mental health is on our minds., Methods: This study combines young people's green space perception, green space use, and purpose of visit to explore its impact on the emotional health of youth groups, combined with the PANAS psychological data scale, an online questionnaire survey of 426 residents (18-35  years old) in three Chinese cities, and was used to construct a multiple regression model and AMOS structural equations., Results and Discussion: The results of the study showed that, firstly, environmental attractiveness, environmental odor, and number of facilities were the key factors influencing adolescents' landscape perception evaluation, while activity space, environmental odor, and environmental attractiveness had a greater impact on adolescents' emotional well-being. Second, among adolescents' visit purposes, socializing and fitness were more likely to help them generate positive emotions while resting and viewing activities were effective in helping them alleviate negative emotions. In addition, in terms of usage, residents who took public transportation as well as those who arrived on foot were the most emotionally healthy. The findings of this paper provide insights for public policymakers, urban planners, and landscape architects to better encourage youth participation in green spaces when they are installed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Liu, Zou, Guo and Chen.)

• Approach of characterizing the thermal environment effect. • Spatiotemporally varying analyzing on time series data. • Evaluation on the cooling effect of different UGS (Urban Green Space) types. • Scientific and rational UGS planning are urgently needed for estuarine watershed. Taking the main city of Fuzhou as the study area, the relationship between the spatiotemporal evolution of urban green space (UGS) and the urban thermal environment from 1993 to 2013 was investigated using a set of remote sensing images. The evolution of UGS is obvious in the study area, where UGS loss (42.83 km2) > UGS extension (4.99 km2) > UGS exchange (2.61 km2). UGS loss affects forest/grass > water > wetland. Furthermore, the area defined as high temperature zones increased by 23.11 km2 in 2013, twice as much as that in 1993. However, the influence of UGS on the urban thermal environment differs by type and evolution: water has the greatest cooling effect, followed by wetland and forest/grass, and UGS loss (8.67 ℃) > UGS exchange (4.00 ℃) > UGS extension (2.90 ℃) > UGS unchanged (2.45 ℃). Finally, the vegetation and cooling index classified the mechanism of temperature response induced by different types of UGS evolution. The evolution of UGS loss usually simulated the movement of the corresponding pixel from the low land surface temperature and high vegetation coverage to the opposite situation. Regression analyses demonstrated that the effect of elevated land surface temperature generated from the reduction of water and forest/grass reached 0.81 ℃ and 0.72 ℃, respectively, in 20 years, indicating that the loss of a significant amount of UGS during urbanization was the primary influence on the urban thermal environment. This study may provide more useful information for researchers and decision-makers engaged in urban planning, urban regeneration, and sustainable land development, especially focusing on the issues of climate adaption and the urban heat island (UHI) effect mitigation. [ABSTRACT FROM AUTHOR]

• Social was the most perceived while culture and rich in species the least. • Preferences are positively related to highly perceived sensory dimensions. • Type of green space strongly affects perceptions of the eight sensory dimensions. • Certain socioeconomic variables affect perceptions of the eight sensory dimensions. • Use variables have influence on perceptions of the eight sensory dimensions. Several evidence from the Nordic countries suggest that the eight perceived sensory dimensions , which are serene , nature , rich in species , space , prospect , refuge , social and culture , can be used as a reliable tool for urban green space assessment and planning, but whether or not this is the case for China is unknown. Using an onsite questionnaire distributed to green space users in Hefei, China, this study is the first to examine the representations of the eight sensory dimensions as perceived by Chinese people in different types of green space, and to identify the relationship between the eight sensory dimensions and preference, including the factors that most influenced their perceptions. The results showed that: (1) Social was common, while culture and rich in species the least common—which was not in line with the previous European studies; (2) The popularity of green space type was positively related to the number of highly perceived sensory dimensions ; (3) Type of green space was a key determinant of perceptions of the eight sensory dimensions , and certain socioeconomic and green space use variables also had a great impact on people's perceptions. The results grant potential to the method in assessment and planning of urban green space in China. [ABSTRACT FROM AUTHOR]

Ecosystem services of urban green spaces play an important role in the sustainable development of the urban ecosystem. How to quantify the ecological benefits of urban green spaces and evaluate their ecological services is a hot topic in related fields. Currently, with the advancement of science and technology, the assessment method has been developed from the traditional ones such as the Council of Tree and Landscape Appraisers (CTLA) method, afforestation cost method, and carbon tax method to CITYgreen and i-Tree. The latter two models have been widely used in countries of Europe and America, while the use of i-Tree has not been promoted in China. In this paper, i-Tree Eco (UFORE) was selected for research, and its application in the assessment of the ecosystem services of urban green spaces, including energy saving, air quality improvement, interception of rainwater, and aesthetic benefits, were analyzed. This study aims to provide a theoretical and scientific basis for the introduction and localization of i-Tree, as well as its generalization in the assessment of forest ecosystem services domestically. [ABSTRACT FROM AUTHOR]

Urban green space (UGS) was widely regarded as an effective nature-based solution to mitigate the urban heat island (UHI) effect, therefore, developing landscape strategies to enhance its cooling intensity (CI) is crucial. However, two main problems prevent the application of results to practical actions: one is the inconsistency of relationships between influencing factors of landscape and the thermal environment; another is the unfeasibility of some common conclusions such as simply increasing the amount of vegetation cover in highly-urbanized areas. This study compared the CIs of UGSs, investigated the influencing factors of CI and identified the absolute threshold of cooling (ToC abs ) of the influencing factors in four Chinese cities with very different climatic backgrounds (Hohhot, Beijing, Shanghai and Haikou). Results demonstrate that local climate condition affects the cooling effect of UGS. The CI of UGS is weaker in cities with humid and hot summer than in cities with dry and hot summer. Patch characteristics (area and shape), the percentage of water bodies within the UGS (Pland&#95;w) and neighboring greenspace (NGP), vegetation abundance (NDVI) and planting structure together can explain a significant proportion (R 2  = 0.403-0.672, p < 0.001) of the CI variations of UGS. The inclusion of water bodies can ensure effective cooling of UGS, except in the tropical city. Besides, ToC abs of area (Hohhot, 2.6 ha; Beijing, 5.9 ha; Shanghai, 4.0 and Haikou, 5.3 ha), and NGP (Hohhot, 8.5 %; Beijing, 21.6 %; and Shanghai, 23.5 %), NDVI (Hohhot, 0.31; Beijing, 0.33; and Shanghai, 0.39) were identified and related landscape strategies of cooling were proposed. The identification of ToC abs values can provide easy-to-use landscape recommendations to UHI mitigation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Urban parks and public transport are indispensable elements of a compact megacity for their environmental and social values. However, few measures of urban park accessibility have considered the public transport travel mode. Based on the framework of geographic information systems (GIS) network analysis, this study proposes an innovative method to incorporate public transport travel mode into urban park accessibility evaluations. Taking Shanghai, China, as the study area, we measured home to park and park from home travel times on multi-modal transport networks, calculated the accessibilities by multiple equations, and compared accessibilities for different districts. These methods extend current accessibility measures by calculating accessibility at a realistic level, and provide a measure of public transport service for urban parks. The results for Shanghai show that approximately 99.95% of home to park routes might include public transport. The distribution of home to park public transport accessibility of the city was uneven. The patches with best accessibility tend to be distributed in the built-up area in the city centre. Public transport access to urban parks is inhomogeneous for different districts, because of urban park locations, road network characteristics, and uneven public transport supply. The distribution of park from home public transport accessibility has no significant correlation with district development stage. Public transport service in Shanghai takes no account of the factors of park star rating or size. Positive actions are required to improve the equity of public transport access to the important public health resources of urban parks. [ABSTRACT FROM AUTHOR]

Urban heat island (UHI) often cause negative impact and has been linked to heart stroke rate, morality, human comfort, energy consumption and air pollution. Fortunately, urban green spaces have been considered as an effective element to mitigate UHI through their cooling effect. However, further empirical research is necessary in order to efficiently guide the design and planning of urban green space. We observed the impacts of urban park's tree, grass and waterbody on microclimate inside the Olympic park of Beijing during summer days. The results indicated that, on average, the park was 0.48–1.12 °C cooler during the day, as well as increased air humidity 2.39–3.74% and reduced human comfort index 1.02–2.43 to generate more comfortable thermal environment. Urban park's cluster trees with short ground vegetation generated higher cooling effect than single trees, grass and waterbodies; proper irrigation regime enhanced the cooling effect of grasses, even the irrigated grass have similar cooling effect with small waterbody on sunny, windless summer days. Therefore, we advise to increase undergrowth coverage and grass irrigation management in order to take advantage of cooling effect of urban parks. [ABSTRACT FROM AUTHOR]

Summary: In water‐scarce regions of China, wastewater reuse is increasingly considered as a potential component of China's future water resource management strategy. Currently, the percentage of wastewater reuse varies substantially across Chinese provinces, but conditions leading to a high rate of wastewater reuse have not been elucidated clearly. In this work, we use fuzzy‐set qualitative comparative analysis (fsQCA) to identify the drivers of high and low percentages of wastewater reuse in water‐stressed Chinese provinces in 2013. We find that among the five conditions studied (per capita water availability, urban population, access to sea, access to urban space, and access to agricultural land), a high percentage of wastewater reuse is primarily driven by water stress and access to urban green space. Consequently, policies should consider targeting provinces with these attributes where wastewater reuse is more likely to be successful. Further, our results show that there is asymmetry in the conditions that lead to high and low percentages of wastewater reuse, and that the drivers for and against reuse identified in this study are not completely analogous to those identified in previous studies. As such, the drivers for and against wastewater reuse should not be generalized without due consideration of the local context. [ABSTRACT FROM AUTHOR]

Urban green space, as an important component of an urban ecosystem, plays an important role in improving the urban living environment, maintaining ecological balance and reducing carbon dioxide concentration. Few studies are focused on carbon dioxide emissions in urban green spaces of cold regions. To thoroughly understand the temporal and spatial variation laws of carbon dioxide concentration and its influencing factors in urban green spaces in cold regions, a LI-COR LI-840 non-dispersive infrared gas analyser was used to explore the variations in the carbon dioxide concentrations of different plant community green spaces at the syringa Park in Qunli New District of Harbin and their influencing factors. Diurnal variation, seasonal variation, annual dynamics, and temporal and spatial distributions of carbon dioxide concentration in the growing season of four types of park green spaces, namely, larix, birch, syringa, and grassland communities, were observed through experiments. Air temperature, surface temperature, air humidity, and atmospheric pressure in the four types of green spaces were measured to further analyse the correlation among the diurnal variation of carbon dioxide concentration, seasonal variation of carbon dioxide concentration, and the corresponding factors of different vegetation types in parks. Moreover, the annual regression equation of carbon dioxide concentration was established. Results show that the carbon dioxide concentration in different community green spaces exhibits an obvious diurnal variation and a tendency of decreasing first and then increasing over time. The seasonal dynamics of carbon dioxide concentration in different types of park green spaces are different. The carbon dioxide concentration of the larix green space is the lowest (dynamics), whereas that of the grassland space is the highest (357.17±30.18 μmol/mol). The larix seasonal dynamics demonstrates the change with the seasons, from highest to lowest as autumn>spring>summer. Temperature is the main controlling factor that affects the variation in carbon dioxide concentration in the growing season. The carbon dioxide concentrations of larix, birch, syringa and grassland show a highly significant positive correlation with surface and air temperatures. A significantly positive correlation is also observed between atmospheric pressure and variation in carbon dioxide concentration in larix and birch. This study provides data reference and support for spatial ecological planning and layout and the selection of plants in urban park green spaces. [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]

The pace of urbanization in China has increased in recent decades. Accordingly, the urbanized area has expanded at a spectacular rate and the urban heat island (UHI) has intensified. Understanding the effects of the landscape pattern on the UHI is crucial for optimizing urban structure, which could mitigate the UHI. This study focused on green cover in an urban area. To investigate how the composition and configuration of urban green patches would affect their temperature in Beijing metropolitan region, China, especially the influence of the configuration of green patches on their cooling effect, the relationships between green surface temperature (GST), normalized difference vegetation index (NDVI), and normalized compactness index (NCI) were investigated by regression analyses, and a method to quantify the cooling effect of greens derived from the urban cool island and green space cool island was proposed. The image from the Landsat Thermal Infrared Sensor was used to estimate GST, and three images from the GF-2 Panchromatic & Multispectral Camera were used to obtain NDVI and calculate NCI. Our results showed that both NDVI and NCI had negative relationships to GST in summer, but only NCI strongly influenced the spatial cooling effect of greens. The further exploration of the influence of NCI on the cooling effect showed the NCI was negatively correlated to the cooling effect, which indicated that, for a given area, more compact green patches reduce the extent of the cooling effect. [ABSTRACT FROM AUTHOR]

The role of urban green space (UGS) in urban sustainability is attracting increasing attention from researchers. How to achieve greener cities in urban development is an urgent problem to be solved. In this study, we investigate the spatio-temporal variation of UGS and its relationship with urban growth in different socio-economic development phases based on an empirical analysis of cities in the Yangtze River Delta region in China during a period of rapid urban development (2001–2019). The remote sensing data reveal a changing UGS pattern that declined notably in the first decade and has increased slightly since 2012, with the green areas mainly clustered in urban centers. We use piecewise linear regression to investigate the impacts of urban growth on UGS from the perspective of growth in the economy, population, and land — in four socio-economic development phases. The results show that the growth of the economy and population reduced UGS in the initial stage of development. Recently, there is more awareness of the importance of environmental issues in socio-economic development. Further, the growth of the economy and population could promote UGS in recent years. Meanwhile, the expansion of urban land boundaries could provide more spaces for UGS. However, the growth of urban land is contrary to the sustainable and compact development of the city. Finally, we discuss the potential of urban growth to improve urban environment, and propose nature-based solutions to mitigate the conflicts between urban compactness and UGS layout. This study supplements the theory of urban growth and the environment with evidence from Chinese cities and offers insights into sustainable urban development in developing regions. • We tracked changing patterns of urban green space (UGS) in Yangtze River Delta (YRD) cities between 2001 and 2019. • The impacts of urban growth on UGS change along with socio-economic development. • Growth of the economy and population initially reduced UGS. • Recently, economic growth and population growth have been linked to improved UGS. • Nature-based solutions can mitigate the conflict between limited urban land boundaries and the demand for increasing UGS. [ABSTRACT FROM AUTHOR]

With the rapid urbanization in Beijing, the vegetated surfaces have been increasingly replaced by impervious built surfaces. A clear recognition on the changes in green spaces pattern is vital for urban administrators and planners to optimize the urban development areas and define the ecological protection red lines. Based on the SPOT images and field investigation data of urban green spaces within the sixth ring road of Beijing in 2000, 2005 and 2010, the study investigated the dynamic changes of urban green spaces in this area, by means of GIS techniques and landscape ecology methods. The results indicated that green spaces in Beijing have decreased by 207 km2 from 2000 to 2010 at the expense of agricultural lands and waters. Although there has been some increases in urban forests and grasslands, it cannot compensate the rapid decrease of urban green spaces. The land cover types conversion occurred mainly in the areas between the fifth and sixth ring roads while the zones encircled by the fourth ring road had a little change. In addition, landscape metrics such as number of patches (NP) and shape index (SHAPE) increased, but the mean neatest-neighbor distance (MNN), aggregation index (AI) and patch cohesion index (COHESION) decreased during the period of 2000-2010. Also green landscapes became considerably isolated and fragmented. The study disclosed the obvious changes of green space size, composition and layout in urban districts of Beijing City from 2000 to 2010 and highlighted that construction of urban green space should consider not only the geometric or aesthetic effect, but also the increase of vertical green volume and optimization of spatial layout to fully develop the ecological service functions of green spaces. [ABSTRACT FROM AUTHOR]

Urban green space (UGS), which plays an important role in reducing the problems associated with urbanization, needs to be evaluated by metrics. Three-dimension green quantity (3DGQ), a quantitative index that measures the crown space occupied by a growing plant, is often used to evaluate the extent, and the environmental and climatic benefits of UGS. The objective of this study was to measure the 3DGQ of Paotaiwan Wetland Park (PWP) in Shanghai, China. Implementation of the 3DGQ index was supported by remote sensing (RS) images taken by an unmanned aerial vehicle (UAV). The 3DGQ calculations for 100 species of trees were used to calculate the 3DGQ of the UGS in PWP. The environmental and climatic benefits of UGS in PWP were also evaluated. The 3DGQ for the whole PWP was 668,624.13 m 3 . The mixed woods in the PWP annually absorbed 1,635.57 t CO 2 , 2.03 kg SO 2 , 735.48 t dust, and 2,254.49 t of O 2 . There was 367.74 t of diurnal transpiration. The lowered temperature of the PWP in the transpiration scope at 100 m altitude was 1.8 °C. The use of a UAV to assess UGS could help planners and policy makers to improve the environmental and climatic benefits of UGS. [ABSTRACT FROM AUTHOR]

This study aimed to build urban green space with environmental functions (e.g., canopy interception of rainfall) and adjust hydrographic balance to some extent for forecasting the potential canopy rainfall interception capacity of landscape trees and the effects on rainfall distribution. The effects of urban green space on interception and runoff reduction have been conceptualized, but not quantified. Therefore, the leaf area index and the water storage abilities of 17 kinds of landscape trees in common use were measured, at Shanghai, and canopy rainfall interception capacity was calculated using the interception formula. The predicted rainfall interception capacity models were established choosing tree morphological characteristics (diameter at the breast height, height, and crown width) as variables. The model test showed that the errors of 12 models were less than 5% between the predicted and the measured data and the errors of four models were within 5 and 10%, with the error for only one model being between 10 and 11%. Also, the study indicated that conifer trees were able to hold more rainfall compared with broad-leaved trees per unit area ( k). The results showed that these models could effectively predict the potential capacity of canopy rainfall interception for landscape trees in Shanghai area and were beneficial for species selection in constructing plant communities, aiming to improve the rainfall interception capacity of urban green space. [ABSTRACT FROM AUTHOR]

Urban green space is widely acknowledged to promote public health through multiple pathways. However, there is limited understanding of how the spatial patterns of green space might play different roles in such a process. This study examined potential pathways through which spatial patterns of green space improved people's life satisfaction (LS) by reducing air pollution. A partial least squares structural equation model was adopted to explore these pathways in sampled urban areas (township) of China (n = 60). Green space spatial patterns were measured using landscape metrics of size, aggregation, fragmentation, and diversity. The results did not show that green space spatial pattern promoted LS by reducing air pollution. However, green space size and fragmentation were negatively associated with air pollution (mainly PM 2.5, PM 10, and NO 2). The pattern of highly densely distributed small green spaces was related to higher LS, as was high diversity of green space type. Simply adopting a fragmented green space pattern to reduce air pollution might be simultaneously associated with reduced LS. This alerts decision-makers and planners to the potential "double-edged sword" effect of optimizing green space structures to improve air quality, which may not yield strongly favorable results due to the impacts that hinder LS. • Green space structures cannot promote life satisfaction (LS) by reducing air pollution. • Green space size and fragmentation are negatively related to air pollution. • More fragmented green space distribution is associated with lower LS. • Higher diversity of green space is related to higher LS. • Fragmentation of green space affects LS more than diversity. [ABSTRACT FROM AUTHOR]

• Focus on the optimal scale of urban green space. • Comprehensively considering the ecological and socioeconomic benefits of urban green space and constructing an evaluation index system. • Calculating the optimal scale of urban green space in Xi'an under different benefit conditions. • Providing new perspectives and references for the future construction of Park Citiy and urban green space system planning. With the acceleration of urbanization in China, urban problems have become increasingly serious, and have led to the concept of the Park City. This concept involves a consideration of the comprehensive value of green space in order to give full play to the maximum benefit of that green space and, thus, realize the sustainable development of the city. Therefore, an exploration of the optimal scale of urban green space will have theoretical and practical significance for the construction of the Park City and the rational allocation of urban land resources. Taking Xi'an as an example, the present paper comprehensively considers the socioeconomic and ecological benefits of urban green space, and calculates its optimal scale. The results indicate that: (i) in terms of the socioeconomic benefits alone, the per capita amount of green area in Xi'an needs to be larger than 11.08 m2, and there is no theoretical optimal size; (ii) in terms of ecological benefits alone, the per capita amount of green area in Xi'an needs to be greater than 22.98 m2; (iii) in terms of the combined socioeconomic and ecological benefits, the per capita amount of green area of Xi'an needs to be greater than 24.89 m2; (iv) the optimal scale for any city is more siginficantly impacted by the ecological effects than by the socioeconomic effects; (v) to satisfy the development and construction needs of various cities, with their individual characteristics, the optimal urban green space scale should be explored according to the target city's developmental stage and land use situation. The methods and results of the present study are intended to provide a reference for the future construction of Park Cities in China, as well as the planning of green space systems in other cities globally, and to open new prospects for future research. [ABSTRACT FROM AUTHOR]

Rapid urbanization has led to a series of environmental problems that are harmful to the physical and mental health of residents. Not only can increasing urban tree canopy (UTC) improve sustainable city development, but it can also effectively promote the quality of life for residents; however, the uneven spatial distribution of UTC can also bring about social justice problems. Currently, there are few studies related to the justice of UTC distribution in China. Based on this, the paper adopts object-oriented image classification technology to interpret and extract UTC data from satellite images, and it uses house price to explore the justice of the spatial distribution of UTC in the main urban area of Guangzhou from the perspective of environmental justice by ANOVA, Pearson correlation coefficient, and bivariate local spatial autocorrelation. The results show that: (1) There is a significant positive correlation between UTC and house price in the main urban area of Guangzhou, and there are regional differences in the distribution of UTC, with the UTC in the "very high" house price group being significantly higher than that in other groups. (2) The spatial clustering of UTC and house price in the main urban area of Guangzhou is found to be "low-low" and "high-high"; thus, it can be concluded that the spatial distribution of UTC in the main urban area of Guangzhou is uneven. This is an environmental injustice, as the areas with low UTC are spatially clustered in old residential areas, while the areas with high UTC are spatially clustered in commercial housing estates with high house prices. The study shows that urban tree planting should not only focus on quantitative improvement but also on equitable spatial layouts to promote social equity and justice thereby improving the urban ecological environment and promoting healthy urban development.