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The complexity and heterogeneity of urban land surfaces result in inconsistencies in near-surface winds, which in turn influence the diffusion and dispersion of air pollutants. In this study, we classified urban surface wind fields, quantified their steadiness, duration, and influence on air quality using hourly wind observations from 50 meteorological stations, as well as hourly PM 2.5 and NO 2 concentrations from 18 monitoring stations during 2017-2018 in Shenzhen, a mega city in southern China. We found that the K-means clustering technique was reliable for distinguishing surface wind patterns within the city. Urban surface-wind patterns greatly affected pollutant concentrations. When dominated by calm, northerly wind, high PM 2.5 /NO 2 concentration episodes occurred more frequently than those during other surface wind patterns. The urban surface transport index (USTI) was used to quantify the steadiness of surface wind classes. High pollutant concentrations were present during both high wind speed periods with a large USTI, indicating external pollutant transport, and during low wind speed periods with a small USTI, indicating pollutant accumulation. The threshold durations for surface wind fields (TDSWF) was proposed to quantify the impacts of surface wind persistence on air quality. We found that poor air quality occurred during the first several hours of a dominant wind pattern, indicating that transitions between wind patterns should be a particular focus when assessing air-quality deterioration. USTI and TDSWF are potentially applicable to other urban areas, owing to their clear definitions and simple calculation. In combination with wind speeds, these indices are likely to improve air quality forecasting and strategic decisions on air pollution emergencies, based on long time series of multiple wind and pollutant concentration observations., 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 © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Land resources are foundational for human survival and development. In contrast, land use/land cover (LULC) dynamics drive considerable changes in ecosystem services. Recently, China witnessed a new stage of rapid urbanization. Therefore, investigating the relationships between ecosystem services value (ESV) and LULC in these areas is highly relevant. Based on the data of land use and socioeconomic development in Shanghai from 2000 to 2020, we adopted a land use/land cover dynamics analysis method and established the ESV per unit area at the city scale, discussed the impact of LULC on ESV spatially and quantitatively, and tested the research process based on the sensitivity analysis of the ESV coefficient. The results show that from 2000 to 2020, the LULC pattern in Shanghai rapidly changed. In particular, the area of cultivated land has shrunk by 123.96 thousand hm 2 , while the construction land has expanded by 141.26 thousand hm 2 , which has led to a decline in ESV of the entire city (especially regarding hydrological adjustment and biodiversity). Nevertheless, although the area of trench and lakes only occupies 1.67-3.16% of the total area of land, its ecological value accounts for an astonishing 23.80-50.70% of the total ESV. At the district level, the primary decline in eco-system services value was noted in the Chongming District in the north and Pudong New Area in the east of Shanghai. However, due to the overall planning of the city and the advantages of its resource endowment, Qingpu District and its surrounding areas in western Shanghai have witnessed improvements in terms of the values of hydrological adjustment, water supply, and environmental purification. This study presents a deeper and more comprehensive understanding of issues regarding ESV in rapidly urbanized areas, thereby providing an important reference for decision-makers regarding the rational layout of cities, sustainable use of land, and management of natural ecosystems.

In this paper, panel data from nineteen key cities in the Sichuan-Chongqing urban agglomeration from 2003 to 2016 were used as the study sample. Using the stochastic impacts by regression on population, affluence, and technology (STIRPAT) model, the effect of foreign direct investment (FDI) on particulate matter (PM 2.5 ) pollution and its action mechanism in the Sichuan-Chongqing urban agglomeration were considered for both socioeconomic and natural factors. The results showed that the "pollution halo" hypothesis of FDI in the Sichuan-Chongqing urban agglomeration has been supported. There are significant positive spatial spillover effects of PM 2.5 pollution in this urban agglomeration, and the introduction of FDI is conducive to alleviating PM 2.5 pollution in the urban agglomeration. Similar to the "inverted U" curve proposed by the environmental Kuznets curve (EKC) hypothesis, there was a significant "inverted U" curve relationship between PM 2.5 pollution and economic growth in the Sichuan-Chongqing urban agglomeration. However, there was a significant "U"-type curve relationship between the urbanization degree and the PM 2.5 concentration, which indicates that the current urbanization mode may aggravate the pollution degree of PM 2.5 in the urban agglomeration in the long term. Furthermore, the two natural factors of annual average temperature and annual precipitation play an important role in PM 2.5 pollution and spatial spillover effect in the Sichuan-Chongqing urban agglomeration. Economic development and rationalization of the industrial structure are the main ways by which FDI affects PM 2.5 pollution in the urban agglomeration. The research conclusions of this study can be of great practical significance to optimize the regional industrial layout, control PM 2.5 pollution, and establish a sustainable development policy system in the Sichuan-Chongqing urban agglomeration.

China's rapid urbanization and industrialization process has triggered serious air pollution. As a main air pollutant, PM 2.5 is affected not only by meteorological conditions, but also by land use in urban area. The impacts of urban landscape on PM 2.5 become more complicated from a three-dimensional (3D) and land function zone point of view. Taking the urban area of Nanchang city, China, as a case and, on the basis of the identification of urban land function zones, this study firstly constructed a three-dimensional landscape index system to express the characteristics of 3D landscape pattern. Then, the land-use regression (LUR) model was applied to simulate PM 2.5 distribution with high precision, and a geographically weighted regression model was established. The results are as follows: (1) the constructed 3D landscape indices could reflect the 3D characteristics of urban landscape, and the overall 3D landscape indices of different urban land function zones were significantly different; (2) the effects of 3D landscape spatial pattern on PM 2.5 varied significantly with land function zone type; (3) the effects of 3D characteristics of landscapes on PM 2.5 in different land function zones are expressed in different ways and exhibit a significant spatial heterogeneity. This study provides a new idea for reducing air pollution by optimizing the urban landscape pattern.

As a typical example of an innovative governance environment, innovative city has become the focus of political and academic circles. Discussing the green innovation effect of this policy is beneficial in providing decision support for enhancing urban green innovation capability and solving the dilemma of urban resources. Based on data from 241 cities in China from 2005 to 2017, this paper takes innovative city construction as a "quasi-natural experiment" and uses the difference-in-differences method to empirically study the impact of China's innovative city construction on urban green innovation. The results show that innovative urban construction: has a positive effect on improving urban green innovation, and that this effect will gradually increase with time; promotes urban green innovation by expanding the scope of technology application, improving the efficiency of resource allocation and promoting the adjustment of industrial structure; and presents heterogeneity in cities' location, size and hierarchy. Finally, this paper proposes that the government should promote innovative policies in an orderly manner on the basis of following the principle of adapting measures to local conditions, as well as incorporating green innovation performance into the evaluation system for innovative city construction., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Sound ecological environment is an important foundation for promoting high-quality urban development, as it determines the level and quality of urban construction and human settlements. Taking Xi'an as the study area, we used remote sensing ecological index (RSEI) to evaluate the urban ecological environment. The evaluation index system of high-quality urban development was constructed and the entire-array-polygon was used to evaluate the urban development quality. The coupling coordination degree model was used to analyze the temporal variations of the coupling coordination degree of those two factors. The results showed that the urban ecological condition of Xi'an showed a pattern of high in the south and low in the north, and that the level of RSEI had an upward trend in 2010-2020. The RESI of the six inner districts of Xi'an decreased, but the RESI of the surrounding districts of Xi'an was stable or improved. The urban development quality of Xi'an was improved in 2010-2020, though the quality level was still at the low level. The improvement of the three major subsystems of urban development was uneven, and the increase range of three subsystems from largest to smallest was ranked as ecological subsystem > economic subsystem > social subsystem. The coupling coordination of the two kinds of index increased in 2010-2020, and the coordination level had been prompted from barely coordinated to primary.

Energy-saving reconstruction of old residential buildings is a vital way to achieve sustainable development, but the potential of rooftop photovoltaic (PV) energy-saving in old residential buildings has not been studied. This study established a basic framework for the estimation of rooftop PV technical, economic and environmental potential in the old residential buildings of Nanjing City, and provide the prediction results for the development of rooftop PV development plan in Nanjing. We estimated the available area, maximum electricity generation, environmental and economic benefits of rooftop PV in five districts of Nanjing by using building roof profile data, calculation method of maximum solar radiation at optimal tilt angle and GIS method. We find that the electricity generation potential of installing rooftop PV in the old residential buildings in the study area would meet about 17.7-20% of the residential electricity demand under three scenarios of the PV performance ratios (PR). Additionally, the carbon reduction potential of the life cycle rooftop PV reaches 13912874.12t (PR = 0.85), 13094469.76t (PR = 0.8), and 12276065.4t (PR = 0.75), respectively; and the result of economic potential shows that the life cycle of rooftop PV cannot generate economic benefits with an NPV value less than 0. The feasibility analysis framework provided in this paper can be applied to the assessment of rooftop PV potential in other cities in China, and provide valuable advice for the rational planning of rooftop PV., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The inability to quantify the difference between ambient temperature (AT) and personal exposure temperature (PET) is a common limitation in environmental health research. The actual exposure variability is underestimated when we used measurements from fixed monitoring stations to estimate PET. The study aims to explore a more reasonable temperature exposure calculation method to relate PET to AT and links heat exposure to adverse health events. We measured hourly PET of 129 participants from July 8th to July 13th, 2021 in Xinyi City, China. The linear mixed-effects model was used to build the relationship between hourly PET and AT in rural and town. Several calculation methods that can capture the intensity, frequency and duration of daily exposure were used to calculate the daily PET and AT and establish the relationship between the two factors. A generalized linear model was used to establish the relationship between city-scale AT indicators and health endpoints from January 1st, 2013 to December 31st, 2015 in Shanghai, China. The result showed that the hourly PET was significantly related to AT, wind speed, air pressure, precipitation, outside time, and air-conditioning use. Among several daily temperature indicators, we found that AT DHAT (Degree Hours Above Threshold (27.4 °C)) was tight with the PET DHAT in different regions (R 2  > 0.99). DHAT strengthened the relationship between daily AT and health endpoint in the urban-scale heat-related health impact study, especially in respiratory diseases. The method proposed in this study can improve the accuracy of future epidemiological studies on the effects of heat exposure., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Rural landscapes offer a variety of cultural ecosystem services (CESs). However, the relationship between rural landscape characteristics and different CESs is still poorly understood. Therefore, this study explored the rural areas of Huzhou city, China, as a case study to assess the main rural landscape characteristics of different CESs based on public preferences. First, 148 scenic spots were classified into four CESs (physical, experiential, intellectual and inspirational), and the public preferences for each scenic spot were determined by combining tourists' scores obtained from social media and government assessment scores. Then, the landscape characteristic indicators were constructed from the natural, infrastructural and sensory perspectives by combining geographic and social media data. Finally, the random forest model was used to evaluate the public preferences for rural landscape characteristics overall and for different CESs. The word frequency analysis showed that, in addition to the nature landscape, infrastructure and service had a strong influence on public preferences. The relationship with rural landscape characteristics varied across different CESs. For physical CESs, the convenience of infrastructure played a greater role than natural landscape characteristics. Experiential CESs, on the other hand, were affected by natural landscape characteristics themselves. Intellectual CESs had higher requirements for both infrastructure and nature. Inspirational CESs included sensory evaluation indicators, in addition to their focus on natural landscape characteristics and infrastructure, indicating that this category of CESs was more concerned with inner experience. The use of social media data has enriched the dimensions of sensory elements and provided new ideas and information supplements for comprehensively understanding different CESs, thus better supporting the management, planning and protection of rural landscapes., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

This study uses behavioral observation, interviews, and questionnaire research to investigate the residential environment. It also evaluates the elderly in four representative ancient towns of Xiangxi, namely, Liye Ancient Town, Furong Ancient Town, Liexi Ancient Town, and Xichehe Ancient Town. It includes indoor air (CO 2 , PM 2.5 , PM 10 ) and light intensity monitoring for the residential environment. The results showed that the elderly had a significant sense of frustration and loneliness. Of the elderyly, 70% believed the current living environment had an impact on healthy living, and 45% believed the safety and convenience of the living environment should be improved. More than 80% of the elderly were dissatisfied with their indoor acoustic environment, and more than 70% were dissatisfied with their home transportation. More than 85% of the elderly considered traditional wooden components and spaces to be the source of cultural identity. Furthermore, the average indoor PM 2.5 concentration during the fire pit fire was 350-600 µg/m 3 , about 4.7-8 times the Chinese standard value. The average concentration of PM 10 in all rooms was more than 400 µg/m 3 , approximately three times the Chinese standard value. Also, targeted environmental improvement strategies were proposed. The study results provided actual information to develop a systematic approach and a targeted design based on the needs to improve the residential environment of the elderly in ancient cities.

We quantify the meteorological influences on daily variations and trends of maximum daily 8-h average ozone (MDA8 O 3 ) concentrations by using multiple linear regression (MLR) and Lindeman, Merenda, and Gold (LMG) approaches. Different from previous region-based studies, we pay special attention to meteorological influences at city scale. Over 2015-2019, daily changes in key meteorological parameters could explain 47%-74% of the observed daily variations in summertime MDA8 O 3 concentrations in Yangtze River Delta (YRD) and four cities (Shanghai, Nanjing, Hangzhou, and Hefei), with RH being the top driver. Over years of 2015-2020, daily concentrations of MDA8 O 3 obtained from MLR equations (MDA8O 3 _MLR) of the local cities always had better performance than those of YRD. Compared with the observed daily MDA8 O 3 in June-July-August (JJA) over the studied period, daily MDA8O 3 _MLR of the local cities (of YRD) had correlation coefficients of 0.73 (0.63), 0.75 (0.74), 0.79 (0.78), and 0.76 (0.73) in Shanghai, Nanjing, Hangzhou, and Hefei, respectively, and the MDA8O 3 _MLR of the local cities (of YRD) captured 54% (17%), 63% (51%), 52% (27%) of the observed O 3 -polluted days (days with MDA8 O 3 concentration exceeding 160 μg m -3 ) in Shanghai, Nanjing, and Hangzhou, respectively. The meteorologically driven trends (Trend_Met) in MDA8 O 3 were calculated using the established MLR equations. Over 2015-2019, the observed trends (Trend_Obs) and Trend_Met in MDA8 O 3 were mostly positive in YRD, Nanjing, Hangzhou, and Hefei. In Shanghai, Trend_Obs, Trend_Met, and anthropogenically driven trend (estimated as Trend_Obs minus Trend_Met) of MDA8 O 3 in JJA over 2015-2019 were -1.3, +1.0, and -2.3 μg m -3 y -1 , respectively, indicating that the emission control measures alleviated O 3 pollution in this city. Our results suggest that it is necessary to establish MLR equations at city scale to account for the role of meteorology in the actions of O 3 pollution control., 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 © 2022 Elsevier B.V. All rights reserved.)

Ambient ozone pollution has been becoming severe and attributed to considerable health impacts in China. Nitrogen dioxide (NO 2 ) is involved in atmospheric ozone production while also affecting public health directly. Joint control ozone and NO 2 pollution would be of significance. This study quantitatively assessed the health impact attributed to ambient ozone and NO 2 pollution in 338 Chinese cities from 2015 to 2020. The results reveal the generally opposite trends of ozone- and NO 2 -related health impacts in China. From 2015-2020, respiratory and chronic obstructive pulmonary disease (COPD) health impacts attributed to ozone in 338 cities increased by 65.30% and 63.98%. The NO 2 -attributed health impacts decreased by 24.80% and 24.62%. In 2020, the ozone- and NO 2 -related respiratory health impacts were 3.96 million DALYs (disability-adjusted life years) and 1.47 million DALYs. High health impacts are concentrated in big cities and city clusters. In 2020, the sum of ozone- and NO 2 -related respiratory health impacts in the top 20 cities was 0.98 million DALYs and 0.44 million DALYs, accounting for 24.70% and 30.24% of the 338 cities. The population attribution fraction analysis identified the increasing distributional consistency of ozone and NO 2 -related health impacts, emphasizing the necessity and possible efficiency of ozone-NO 2 joint control. Emission source analysis based on gridded data provided a reference for understanding health impacts and developing targeted strategies., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

With the advent of the information technology revolution and the Internet era, information technology is gradually occupying an important position and becoming an important strategic factor in economic development. As an emerging technology that has been developing continuously in recent years, big data is becoming an important industry to improve the innovation and development of the urban economy. Like AI technology, cloud computing, and the Internet, big data has become an important application technology for economic growth and economic efficiency improvement in today's world. It is an effective means of progress and development in a region and an important strategic resource. As a new technology, big data has attracted more and more attention from all walks of life. Many companies have turned their attention to developing big data for economic benefits. "Enjoy your old age" is the yearning of every old man and his family. In recent years, the national level has been committed to "creating an urban built environment for the elderly to achieve healthy aging." From the perspective of promoting the physical and mental health of the elderly, this paper analyzes the impact of the urban built environment on the physical and mental health of the elderly based on the needs of the elderly and puts forward countermeasures and suggestions based on the current status and existing problems of the urban built environment for the elderly. Based on the combined data analysis method and technology in big data, this paper conducted a field questionnaire survey on a total of 4,000 elderly people in urban and rural areas by means of the questionnaire survey. It is found that the existing problems of the built environment in the old cities include scattered content, one-sided understanding, and rigid design. According to the problems, the solutions of building consensus, paying attention to planning, combining urban characteristics, and the joint efforts of all sectors of society are put forward. And programming tools are used to combine formulas and analyze related data in detail. The analysis results show that the physical and mental health index of the elderly is highly correlated with factors such as changes in the consensus degree of the urban built environment, urban built environment planning, urban built environment policy support, and multiparty efforts in the urban built environment. Changes show a positive change., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Shuting Yan et al.)

Based on the panel data of 279 cities in China from 2003 to 2017, this paper regards the new energy demonstration cities (NEDC) construction as a quasi-natural experiment, using the double-fixed effect model and the difference-in-differences (DID) method to test its local carbon emission reduction effect and transmission mechanisms and further explores the impact of NEDC on neighboring carbon emissions. Results show that (1) NEDC reduces carbon emission intensity and per capita carbon emission significantly and shows dynamic sustainability. The policy effect has shown a trend of increasing year by year. Moreover, there is significant heterogeneity in the carbon emission reduction effect of NEDC, which produces more significant policy effect in large-scale and non-resource-based cities. (2) NEDC construction reduces carbon emission through green technology innovation effect, innovative elements agglomeration effect, and total factor productivity improvement effect. In terms of the contribution of reducing carbon emission intensity and per capita carbon emission, total factor productivity accounts for 36.7% and 21.5%, respectively, green technology innovation accounts for 18.6% and 23.9%, respectively, the contribution of R&D personnel agglomeration is 7.5% and 8.3%, respectively, and the contribution of R&D capital agglomeration is 5.9% and 9.5%, respectively. (3) From the perspective of spatial effect, the impact of NEDC on carbon emissions presents a "siphon" effect; that is, although NEDC reduces local carbon emissions, it has produced the phenomenon of transfer to neighboring areas, accelerating the increase in the carbon emission intensity of neighboring areas., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

To achieve urban sustainability, it is critical to enhance the environment, economy, and society simultaneously. This study adopted the revised genuine progress indicator (GPI) and ecological footprint (EF) to evaluate the ecological efficiency and economic sustainability of the Yangtze River Delta from 2000 to 2018. Spatial analysis was utilized to identify spatial autocorrelation. A total of 27 cities were then partitioned through k-means cluster analysis. The results showed that GPI and ecological efficiency improved rapidly, but economic sustainability showed a downward trend. GPI and GDP had a high degree of spatial correlation, especially in Suzhou-Wuxi-Changzhou Metropolitan Area. However, no spatial correlation existed between GPI and EF. The city with high GEE can reach 3000 $/gha, indicating the city consumed 1 global hectare to create $3000 of genuine economic growth. Shanghai, Hangzhou, and Taizhou were cities with the highest level of economic sustainability and ecological efficiency. The spatiotemporal characteristics of economic sustainability and ecological efficiency revealed in this study will provide theoretical guidance for alleviating ecological pressure and promoting economic sustainable development., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A multiscale analysis of meteorological trends was carried out to investigate the impacts of the large-scale circulation types as well as the local-scale key weather elements on the complex air pollutants, i.e., PM 2.5 and O 3 in China. Following an accompanying paper on synoptic circulation impact (Gong et al., 2022), using a multi-linear regression model, the trends of key meteorological elements at local scale, i.e., temperature, relative humidity, solar radiation, PBL height, precipitation and wind speed, are analyzed and correlated with the trends of PM 2.5 and O 3 levels to identify significantly influencing factors in seven Chinese cities. Furthermore, with additional emission surrogates introduced in the regression model, the impacts on the trends by meteorology and emission were separated and quantified. Results show that the increasing trends of O 3 at most Chinese cities were largely attributed to the trends of meteorological elements of temperature and solar radiation, while the trends of PM 2.5 are mostly contributed by the emission reduction measures of PM 2.5 and its precursors. The meteorology alone can explain approximately 57-80% of the O 3 variations and only 20-33% of the PM 2.5 variations. With the addition of emission surrogates, this explanation percentage is increased to about 57-82% for O 3 but significantly enhanced to 71-83% for PM 2.5 ., 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 © 2022 Elsevier B.V. All rights reserved.)

Background: Women are vulnerable to depression during postpartum period. While several studies have shown associations between ambient air pollution exposure and depression in general population, there was few studies focused on the effect of various air pollutants on postpartum depression (PPD)., Objective: This study is designed to explore the association between prenatal exposure to air pollutants and PPD, and to reveal the potential vulnerable exposure time point., Methods: The study enrolled 10,209 pregnant women who delivered between October 2019 and February 2021 in 5 participating hospitals from 3 cities in China. Edinburgh Postnatal Depression Scale (EPDS) was administered at 6 weeks postpartum to identify PPD symptoms. Associations between PPD symptoms and exposure levels in PM 2.5 , PM 10, SO 2 , CO, NO 2 , and O 3 averaged over the whole pregnancy and each trimester were estimated using logistic regression models after adjusting for potential confounding factors. Distributed lag models (DLMs) were used to determine the relevant associations in each gestational week., Results: The risk for developing PPD symptoms was significant following a 10 μg/m 3 increase in PM 10 (aOR = 1.47, 95%CI:1.36-1.59), NO 2 (aOR = 1.63, 95%CI:1.44-1.85), and 0.1 mg/m 3 increase in CO (aOR = 2.31, 95%CI: 1.99-2.69) during the whole pregnancy. Similar results were also found in exposure during each trimester of pregnancy. Besides, SO 2 exposure during the second trimester was a major risk factor for developing PPD symptoms (aOR = 1.10, 95%CI:1.03-1.18). Consistent effects were also observed in DLMs, except for PM 2.5 and O 3 , which showed no significant sensitive windows throughout pregnancy period., Conclusion: Exposure to PM 10 , CO, NO 2 , and SO 2 in pregnancy is associated with increased risks of developing depression at 6 weeks postpartum. Our findings reveal the importance of air pollution control for preventing maternal mental health disorders among the public., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The Beijing-Tianjin-Hebei region is an important economic growth pole in China and achieving carbon emission reduction in the region is of great practical significance. Studying the heterogeneity of the influencing factors of carbon emission in this region contributes to formulating targeted regional carbon emission reduction policies. Therefore, this paper adopted thirteen cities as individuals of cross-section and conducted spatial and temporal heterogeneity analysis of the influencing factors of converted carbon emissions in the region with panel data from 2013 to 2018 based on the PGTWR model. From a space-time perspective, the regression coefficient of each influencing factor in this region has obvious heterogeneity, which is mainly reflected in the time dimension. In the study period, the impact of industrial structure, the level of urbanization, energy intensity, and the level of economic growth on carbon emission showed a decline curve, while the impact of the level of opening up and the size of population was on the rise, indicating that more attention should be paid to the latter two factors for the time to come. In terms of space, the differences in the influence of industrial structure and energy intensity on carbon emission vary significantly.

Using surface air temperature observations from 1901 to 2020, this study compared the warming trends of Shanghai and Hong Kong over a period of 120 years. The statistical results reveal the following: (1) The average temperatures of the two cities underwent fluctuating increases during the past 120 years, with linear warming rates of 0.23 °C/decade in Shanghai and 0.13 °C/decade in Hong Kong. (2) The fluctuation ranges of maximum temperature in the two cities were considerably higher than those of mean temperature. Moreover, in both cities, the annual mean maximum temperature decreased during a phase of more than a decade. The fluctuation ranges of minimum temperature were smaller, whereas the linear increases were higher than those for the mean temperature. (3) The diurnal temperature ranges (DTRs) of the two cities decreased; a certain phase of the decreases in DTR in the two cities was caused by decreases in the maximum temperature. (4) At a certain stage of urban development, owing to the shading effect of new high-rise buildings, the solar shortwave radiation reaching the Earth's surface decreased, and anthropogenic heat generated by the energy consumption of buildings and urban human activities at that time was not sufficient to make up for the reduced shortwave radiation. This result may have led to the declines in the maximum temperature experienced by both cities. (5) Currently, the number of hot days and extremely hot days in the two cities has increased significantly compared with that a century ago, indicating that climate warming has an adverse impact on human settlements.

Traditional settlements have received increasing attention because of China’s rural revitalization. Traditional settlements with excellent thermal comfort in rural areas can attract urban residents, so it is vital to explore the thermal comfort of traditional settlements. For this paper, we studied Linpan settlements, which are scattered traditional settlements that are mainly composed of buildings and trees. Firstly, we visually interpreted Linpan settlements by ArcGIS. A total of 1194 Linpan settlements were classified to obtain the spatial components. The statistical results of Linpan were used in the subsequent experimental design. Then ENVI-met was used to simulate 25 different spatial forms of Linpan obtained by statistical results and orthogonal experiment to explore the most comfortable Linpan layout. The results showed the following: (1) Linpan could improve thermal comfort in both winter and summer. Adjusting the spatial arrangement could maximally increase the mean physiological equivalent temperature (PET) of the whole Linpan area by 1.03 °C in winter and reduce it by 3.02 °C in the summer. (2) At different time points, the influence of different space factors on thermal comfort was also different. The overall significance of each factor on thermal comfort was addressed as follows: vegetation coverage (highly significant) > building number (highly significant) > building form (highly significant) > vegetation distribution (significant), but the building distribution was not significant. (3) The best spatial arrangement scheme was high vegetation coverage, a large number of buildings, tri-courtyard buildings, surrounding vegetation distribution, and surrounding building distribution. The innovation of this paper lies in introduced thermal comfort into the traditional Linpan settlement, extracted spatial features of buildings and vegetation by visual interpretation combined with GIS software, and the fact that we conducted the experimental design of microclimate and thermal comfort based on spatial features. The research results can guide the outdoor thermal environment renewal design of Linpan and other traditional settlements.

Water-saving scientifically proved measures are crucial to reduce the use of decreasing fresh water resources. In this study, we investigate the current situation of residents' domestic water use, analyze the current situation of residents' water-saving measures, the current situation of residents' water-saving consciousness and its influencing factors. We performed a questionnaire survey and data obtained by relevant water supply departments, this paper used SPSS 19.0 and Excel 2020 software to conduct statistical analysis of survey data. Our results show that: (1) overall, the water consumption of urban residents in the central plains suburb is 18% higher than that of the original urban residents. (2) Among the residential water structures, washing, washing clothes and flushing toilets are the most frequent tasks, accounting for 87.3% of the total water consumption. (3) The implementation of water-saving measures by the original urban residents is better than that of the original suburban residents. (4) It is necessary to increase effective water-saving facilities and measures for urban water use.

With the acceleration of urbanization, the proportion of surface imperviousness is increasing continuously in cities, resulting in frequent waterlogging disasters. In this context, storm water management, based on the low-impact development (LID) concept, offers an effective measure for the management of urban storm waters. First, the storm water management model (SWMM) was built for a typical cold climate city (Changchun) in China. Next, the two-stage calibrated model was employed to explore the surface runoff and storm sewer control effects of four LID combination plans. Finally, these plans were put through a "cost-benefit" evaluation through an analytic hierarchy process. According to the results, after using four LID plans, the reduction rates of peak runoff exceeded 40% and the problem of overflow load of the storm sewage was significantly mitigated. The infiltration-oriented Plan I proved to be the optimal plan, with the lowest proportions of the overflow nodes and full-load pipe sections in each return period, as well as with maximum overall performance. This study offers technical and conformed methodological support to cold cities for the prevention and control of waterlogging disasters and recycling of rainwater resources., (Copyright © 2021. Published by Elsevier Inc.)

Urban scaling law provides a quantitative understanding of the fundamental nonlinear properties of how cities work. Addressing this, this study intended to examine the potential scaling law that may lie in urban air pollution. With ground-monitored PM2.5 data and statistical socioeconomic factors in 265 Chinese cities (2015-2019), a targeted analysis, based on the scaling power-law model and scale-adjusted metropolitan indicator (SAMI) was conducted. The main findings of this study were summarized as follows: (1) A significant sublinear scaling relationship between PM2.5 and urban population size indicated that air quality degradation significantly lagged behind urban growth, affirming the remarkable effectiveness of national efforts on atmospheric environment improvement. (2) SAMI analysis expressed the relative conflict risk between PM2.5 pollution and urbanization and showed significant spatial cluster characteristics. Cities in central China showed higher potential risk than other regions, and there was a clear southward tendency for the city clusters with increasing SAMIs during the study period. (3) During the study period, urbanization was not the reason affecting the human-land conflict in terms of air pollution. This study is significant in that it marked the first innovative incorporation of the scaling law model into an urban environmental risk study. It also offered a new perspective from which to reframe the urban PM2.5 pollution risk, along with the nationwide air environmental effort in China, which will benefit future research on multi-types of urban environmental issues.

Global climate change results in an increased risk of high urban temperatures, making it crucial to conduct a comprehensive assessment of the high-temperature risk of urban areas. Based on the data of 194 meteorological stations in China from 1986 to 2015 and statistical yearbooks and statistical bulletins from 2015, we used GIS technology and mathematical statistics to evaluate high-temperature spatial and temporal characteristics, high-temperature risk, and high-temperature vulnerability of 31 cities across China. Over the past 30 years, most Chinese cities experienced 5-8 significant oscillation cycles of high-temperature days. A 15-year interval analysis of high-temperature characteristics found that 87% of the cities had an average of 5.44 more high-temperature days in the 15-year period from 2001 to 2015 compared to the period from 1986 to 2000. We developed five high-temperature risk levels and six vulnerability levels. Against the background of a warming climate, we discuss risk mitigation strategies and the importance of early warning systems.

The development of urban agglomeration further deteriorates the air pollution status arising from urbanization. However, disparities in the urbanization process across different urban agglomerations may shape unique regional air pollution characters, and further complicate its driving mechanism. In this study, 11 urban agglomerations with different urbanization levels in China thus were chosen as the case study areas, to explore the spatiotemporal heterogeneity of PM2.5 and its potential driving difference related to the urbanization process from a multi-urban agglomeration perspective. The ground-monitored PM2.5 data and socioeconomic panel data (2015-2018) were processed using multiple statistical analysis methods, and the main findings of this study can be generated as followed: (1) significant spatial heterogeneity characteristics of PM2.5 pollution were recognized across the study area. And even though obvious improvement in the air quality during the study period, PM2.5 concentration remains at a high level for most of the urban agglomerations. (2) Urbanization process has a substantial contribution to regional PM2.5 pollution, and significant differences of the urbanization factors on PM2.5 concentration across the urban agglomerations assigned with various urbanization levels were emphasized. The significance of this study is to provide insight into the relationship of the urbanization process on PM2.5 pollution in different urban agglomerations and to offer a scientific basis for regional cooperation for air pollution regulation among multiple urban agglomerations., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Both innovation-driven development and green development are important ways to achieve regional sustainable development. This study considers the innovation-driven development and green development evaluation systems of 130 cities in the Yangtze River Economic Belt. The entropy TOPSIS method is used to measure the innovation-driven development index and the green development index of 130 cities in the Yangtze River Economic Belt. Then, a coupling coordination evaluation model and a spatiotemporal heterogeneity analysis model are constructed to discuss the coupling coordination index of regional innovation-driven development and green development in the Yangtze River Economic Belt and to determine its temporal and spatial distribution characteristics. Finally, we choose a spatial panel regression model to explore the relationship between the innovation-driven development index and the green development index of the Yangtze River Economic Belt. The research results show that there is a significant difference between the innovation-driven development index and the green development index of the 130 cities in the Yangtze River Economic Belt in terms of the temporal and spatial distribution. The level of innovation-driven development lags behind the level of green development on the whole, and the two fail to form a good spatial matching degree. The coordination index of the two has an imbalanced distribution feature, and there is a significant direct or indirect relationship between the two structural indicators in a mathematical sense. This study improves the academic community's understanding of the interaction between innovation-driven development and green development, provides scientifically based support for green development, and offers guidance for the implementation of innovation capabilities., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Traffic emission is one of the main sources of haze pollution, but few studies have evaluated the dynamic impact and mechanism of transportation infrastructure on haze pollution based on a spatial perspective. This study selects the annual data of 30 provinces in China from 2000 to 2017 and uses a dynamic spatial Durbin model to study the dynamic impact of transportation infrastructure on haze pollution. The results show that transportation infrastructure has a significant spatial spillover effect on haze pollution, and the spatial spillover effect has regional heterogeneity. Specifically, whether long term or short term, highway traffic has a boosting effect on haze pollution, while railway traffic has an inhibitory effect on haze pollution. In addition, transportation infrastructure can affect haze pollution through three paths: expanding economic scale, promoting transformation of industrial structure, and promoting technological progress. At the regional level, the improvement of highway traffic density in eastern, central, and western regions will significantly increase haze pollution. The enhancement of railway traffic density has a significant inhibitory and boosting effect on haze pollution in central and western regions, respectively. For the eastern region, railway traffic construction can only restrain local haze pollution, but cannot exert the spatial spillover effect of railway traffic to reduce haze. The conclusions of this paper provide policy inspirations for giving full play to the haze reduction effect of transportation infrastructure and the development of green transportation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Having high spatio-temporal resolution data of pollutants is critical to understand environmental pollution patterns and their mechanisms. Our research employs the hourly average concentration data on the air quality index (AQI) and its six component pollutants (PM 2.5 , PM 10 , SO 2 , NO 2 , CO, and O 3 ) in 336 Chinese cities from 2014 to 2019. We analyze annual, seasonal, monthly, hourly, and spatial variations of different air pollutants and their socioeconomic factors. The results are as follows. (1) Air pollutants' concentration in Chinese cities decreased year by year during 2014-2019. Among the primary pollutants, PM 2.5 dominated pollution days, accounting for 38.46%, followed by PM 10 . Monthly concentration curves of AQI, PM 2.5 , NO 2 , SO 2 , and CO showed a U-shaped trend from January to December, while that of O 3 presented an inverted U-shaped unimodal pattern. Regarding daily variation, urban air quality tended to be worse around sunrise compared with sunset. (2) Chinese cities' air quality decreased from north to south and from inland to coastal areas. Recently, air quality has improved, and polluted areas have shrunk. The six pollutant types showed different spatial agglomeration characteristics. (3) Industrial pollution emissions were the main source of urban air pollutants. Energy-intensive industries, dominated by coal combustion, had the greatest impact on SO 2 concentration. A "pollution shelter" was established in China because foreign investment introduced more pollution-intensive industries. Thus, China has crossed the Kuznets U-curve inflection point. In addition, population agglomeration contributed the most to PM 2.5 concentration, increasing the PM 2.5 exposure risk and causing disease, and vehicle exhaust aggravated the pollution of NO 2 and CO. The higher China's per capita gross domestic product, the more significant the effect of economic development is on reducing pollutant concentration., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

To improve the accuracy of dietary risk assessment of arsenic (As) from aquatic products, toxic As species (As(III), As(V), monomethylarsonic acid [MMA], and dimethylarsinic acid [DMA]) and total As were analyzed in 124 marketed aquatic products from eight coastal cities in China. Distribution characteristics of Toxic As (the sum of the four toxic As species) in the samples and associated risk of human dietary exposure were emphatically investigated. The impact of cooccurrence of As and other chemical elements in the aquatic products was assessed based on our former results of mercury (Hg) and selenium (Se). Toxic As contents (maximum value 0.358 mg kg -1 wet weight) in the samples accounted for at most 14.1% of total As. DMA was the major component (mean proportion 50.8% for shellfish, 100% for fish) of Toxic As in aquatic products. Shellfish contained more Toxic As than fish did. Mean estimated daily intakes of Toxic As for the residents with aquatic product consumption rates of 46.1-235 g day -1 ranged from 0.034 to 0.290 μg kg -1 day -1 . Potential health risk was indicated among those who greatly consumed aquatic products, as their target hazard quotient (THQ) and target cancer risk (TR) values exceeded safety thresholds (1 for THQ, 10 -4 for TR). DMA and MMA exposure contributed to 3.42-7.72% of the THQ Toxic As . Positive correlations between concentrations of As and Hg (Fish: r = 0.47, p < 0.01; Shellfish: r = 0.60, p < 0.01), as well as between that of As and Se (Fish: r = 0.69, p < 0.01; Shellfish: r = 0.37, p < 0.01) were found in the samples. It requires attentions urgently that As and Hg coexposure through aquatic product consumption rose the sum THQ of Toxic As and methylmercury (MeHg) to approximately two to eight times as high as the THQ Toxic As ., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

As one of the most concerned issues in modern society, air quality has received extensive attentions from the public and the government, which promotes the continuous development and progress of air quality forecasting technology. In this study, an automated air quality forecasting system based on machine learning has been developed and applied for daily forecasts of six common pollutants (PM 2.5 , PM 10, SO 2 , NO 2 , O 3 , and CO) and pollution levels, which can automatically find the best "Model + Hyperparameters" without human intervention. Five machine learning models and an ensemble model (Stacked Generalization) were integrated into the system, supported by a knowledge base containing the meteorological observed data, pollutant concentrations, pollutant emissions, and model reanalysis data. Then five-year data (2015-2019) of Beijing, Shanghai, Guangzhou, Chengdu, Xi'an, Wuhan, and Changchun in China, were used as an application case to study the effectiveness of the automated forecasting system. Based on the analysis of seven evaluation criteria and pollution level forecasts, combined with the forecasting results for the next 3-days, it is found that the automated system can achieve satisfactory forecasting performance, better than most of numerical model results. This implied that the developed system unveils a good application prospect in the field of environmental meteorology., 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 © 2021 Elsevier B.V. All rights reserved.)

With the rapid development of urban agglomerations, urban water use and wastewater environments have gradually constrained sustainable development and caused increasing concern. In this paper, we selected the urban agglomeration on the middle reaches of the Yangtze River (UAMRYZ) as a typical area. We proposed an integrated urban water use and wastewater treatment (UWUWT) system and its urban water use (UWU) subsystem and urban wastewater treatment (UWT) subsystem. Moreover, an integrated two-stage slacks-based measure (SBM) data envelopment analysis (DEA) model was used to evaluate the efficiency of the UWUWT system and its subsystem during 2010 to 2017. Additionally, the multiscale geographically weighted regression (MGWR) model was adopted to analyze the influence mechanism of each factor on the defined system. The results indicated that the tendency of UWU efficiency and UWUWT efficiency were similar and mainly showed the same trend with an 'N' shape in a time-dependent manner for the UAMRYZ and provinces, respectively. Furthermore, the UWU efficiency and UWUWT efficiency of each city showed strong spatiotemporal heterogeneity. The UWT efficiency of the UAMRYZ and its representative cities was stable in the region and always had a higher value. With continuous economic development and increased interregional foreign trade, the UWU subsystem efficiency and the UWUWT system efficiency had a significant increase for cities along the entire river in the Yangtze Basin. The regional differences of the overall UWU efficiency, UWT efficiency and UWUWT efficiency gradually decreased and the efficiency has gradually improved from 2010 to 2017. Attribution analysis showed that the secondary industry was the main constraining factor, while the water resource was the most acceleration factor for the UWUWT system in most areas and the UWT subsystem for all cities. Our study evaluated the specific insufficiencies of the defined system and supported regulatory policies., 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 © 2021. Published by Elsevier B.V.)

The field of rapid urbanization has recently paid more attention to the relationship between tourism development and liveable city construction. Previous studies have mainly focused on the experiences of tourists in tourist cities and seldom paid attention to the perceptions of local residents. Based on survey data of nearly 10,000 permanent residents in 40 key tourist cities in China, this study uses a multilevel model to quantitatively analyse the natural environment characteristics, sociocultural environment characteristics and comprehensive attraction of tourism in different tourist cities to explore their impact on urban liveability satisfaction. Results show that the developed tourist cities do not exactly correspond to the cities with a high liveability evaluation. The objective evaluation of both the natural environment and the sociocultural environment has an important influence on the liveability of cities, but the influence of the natural environment is stronger than that of the sociocultural environment. An intermediary effect exists in the subjective evaluation of the natural environment and environments for liveability perception. Simultaneously, residents' liveability satisfaction varies according to their age, education level, annual household income and other social and economic conditions. These findings provide insights for developing countries to further improve residents' living quality and urban construction under the condition of the rapid development of tourism.

In order to clarify the evolution characteristics and direction of urban energy performance concepts, reveal the research dimensions, determine the performance results and differences, and clarify the reference benchmark, this study depicts the main systems involved in the process of urban energy utilization, demonstrates their relevance guided by the system view, and proposes the measurement indicators in the economic, environmental, and well-being dimensions. The measurement model of each dimension is constructed using the corresponding models of Data Envelopment Analysis. Taking 142 prefecture level cities in China as examples, the energy performance in different dimensions is measured and compared. The energy performance levels are close in the economic and environmental dimensions. However, the results of the well-being dimension are different from these first two dimensions, and the performance levels among cities differ more. In the economic, environmental, and well-being dimension, 22, 28 and 16 cities have reached the effective frontier, respectively, and the performance benchmark cities of 15, 15 and 5 provinces are non-provincial capital cities, respectively. Based on the above analysis, the "chain" framework evolution direction of concept and measurement is proposed, and this study provides benchmarks and policy suggestions to improve energy performance.

Global climate change and local urban heat islands enhance urban heat stress. Studies focused at the urban neighborhood scale are limited. Wet-bulb temperature represents the combined effects of both temperature and humidity, and therefore can more accurately reflect human thermal comfort. In this study, air temperature, relative humidity and geographic information of different times, seasons, and sky conditions of the Nanjing Jiangbei New Area were obtained based on mobile measurements. The spatiotemporal variation of wet-bulb temperature at the urban neighborhood scale and the effects of sky conditions, land cover and urban morphology (sky view factor, SVF) were further analyzed. The results showed that: 1) the spatiotemporal variations of wet-bulb temperature at the Nanjing urban neighborhood scale were consistent with that of air temperature. Compared with vapor pressure, air temperature played a dominant role. The extremely high values of wet-bulb temperature in this area were mostly caused by the synergy between air temperature and vapor pressure. 2) The correlation between SVF and wet-bulb temperature was significantly positive in the daytime and negative at night. An increase in the vegetation fraction could reduce wet-bulb temperature, while impervious surfaces had the opposite effect. The wet-bulb temperature significantly decreased and its spatial distribution was much more homogeneous under overcast sky conditions. 3) The horizontal scale effect showed diurnal and seasonal differences and was more sensitive to sky conditions during nighttime than during daytime. Compared with vegetation, the horizontal effect of impervious surfaces was much larger in winter than in the other two seasons. The horizontal scale effects of vege-tation and impervious surfaces on wet-bulb temperature were similar to those of air temperature. These results could provide effective scientific support and a theoretical basis for improving and optimizing the thermal environment of urban neighborhoods, as well as alleviating urban heat stress.

Improving air quality is an urgent task for the Beijing-Tianjin-Hebei (BTH) region in China. In 2018, utilizing 365 days' daily concentration data of six air pollutants (including PM 2.5 , PM 10 , SO 2 , NO 2 , CO and O 3 ) at 947 air quality grid monitoring points of 13 cities in the BTH region and controlling the meteorological factors, this paper takes the implementation of the Blue Sky Defense War (BSDW) policy as a quasi-natural experiment to examine the emission reduction effect of the policy in the BTH region by applying the difference-in-difference method. Results show that the policy leads to the significant reduction of the daily average concentration of PM 2.5 , PM 10 , SO 2 , O 3 by -1.951 μg/m 3 , -3.872 μg/m 3 , -1.902 μg/m 3 , -7.882 μg/m 3 and CO by -0.014 mg/m 3 , respectively. The results of the robustness test support the aforementioned conclusions. However, this paper finds that the concentration of NO 2 increases significantly (1.865 μg/m 3 ). In winter heating seasons, the concentration of SO 2 , CO and O 3 decrease but PM 2.5 , PM 10 and NO 2 increase significantly. Besides, resource intensive cities, non-key environmental protection cities and cities in the north of the region have great potential for air pollutant emission reduction. Finally, policy suggestions are recommended; these include setting specific goals at the city level, incorporating more cities into the list of key environmental protection cities, refining the concrete indicators of domestic solid fuel, and encouraging and enforcing clean heating diffusion.

Understanding the balance between supply and demand of ecosystem services (ESs) is helpful for sustainable urban management. However, the interactions among multiple ESs supplies and demands remain under-researched, and ESs supply and demand spatial heterogeneity and correlation characteristics at the city level are rarely studied, especially in arid areas. To fill this gap, we established a comprehensive assessment framework of ESs supply and demand through integrating multi-source remote sensing data, social economy, and policy objectives, for the oasis city of Urumqi, China. The ESs supply-demand mismatches were revealed at the city level, and the spatial relationship between the ESs supply and demand was analyzed using spatial statistics. The results demonstrated that: (1) The total quantity of supply and demand of food provision, carbon sequestration, PM 10 removal, and recreation services in Urumqi revealed that the demand was greater than the supply, the deficits being 16.10 × 10 7  kcal/ha, 6.88 × 10 4  t/ha, 155.86 kg/ha, and 697.26, respectively. (2) The supply and demand assessment of ESs revealed spatial differences from the city center to the suburbs, which further indicated that there are neighborhood similarities between the supply and demand of ESs. (3) The matching types of ESs supply and demand present obvious spatial heterogeneity, which can be divided into four types: High-high, high-low, low-high, and low-low. Owing to rapid urban development in the inner city, the city center is dominated by low-high, whereas the urban-rural ecotone is characterized by high-low, owing to the higher elevation and water resource advantages in the suburbs. Based on the analysis of the supply, demand, and matching of ESs, economic development and sustainable management policies are proposed for different ecological spaces. Integr Environ Assess Manag 2021;17:1293-1304. © 2021 SETAC., (© 2021 SETAC.)

Spatial planning is crucial for sponge city (SC) construction; however, prioritizing SC sites at the watershed scale has not been fully explored. In this study, a multi-criteria decision model, considering demand and suitability of SC construction, was established by monitoring, model simulation, and index calculation. This new model was then tested in a rapidly urbanizing watershed, Beijing, China, and the priority of SC construction at both grid scale (1km×1km) and subwatershed scale was ranked. The results showed that the highest priority was found in emerging regions where urbanization is ongoing and followed by urban core areas. In addition, six indexes were identified by clustering heatmaps as key factors affecting the priority of SC planning, including topographic index, water pollution index, pollution rate based on the state standard of surface water environment quality, urbanization planning, urban levels, and vegetation index, which could guide SC planning in data-lacking regions. The approach and findings in this study cannot only provide helpful references for watershed managers and urban planners but also can be easily used in other regions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Tourism is crucial for promoting industrial development and is an important driver of China's new type of urbanization. A tourism urbanization index system was constructed in three dimensions: the tourism industry, urbanization, and the ecological environment. The spatial-temporal differentiation characteristics and influencing factors of tourism urbanization in 35 major tourist cities in China from 2009 to 2018 were analyzed using the state space method, standard deviation ellipse, and spatial autocorrelation analysis. The results show the following. (1) Over time, the tourism industry index displays an upward trend, the urbanization index exhibits a more obvious upward trend, and the ecological environment index fluctuates strongly. Under the influence of all three factors, the tourism urbanization index shows a fluctuating rising trend. (2) Regarding the spatial distribution pattern, the development center of tourism urbanization shifts to the southeast, and the distribution direction is northeast-southwest. There is a significant agglomeration in global spatial autocorrelation. The local spatial correlation pattern is dominated by correlation characteristics and supplemented by different characteristics. (3) In terms of influencing factors, policy and regional development strategy, tourism resource endowment, economic development level, and traffic conditions are listed in descending order of influencing degree. Finally, we put forward some suggestions.

Achieving accurate prediction of the Municipal Solid Waste (MSW) generation is essential for the sustainable development of the city. This paper selects Beijing as the research object, building a neural network model based on Grey Relational Analysis and Long and Short-Term Memory (GRA-LSTM), and choosing 14 influencing factors of MSW generation as the input indicators, to realize the effective prediction of MSW generation. Then this study obtains the landfill area in Beijing by using the aforementioned prediction results and the calculation formula of the landfill. Firstly, the GRA method is used to sort the influencing factors of the MSW generation for obtain the key influencing indexes. Secondly, the LSTM model is used to learn features of the key influencing indexes. Finally, the area of Beijing landfill is estimated by the calculation formula of landfill area. The results show that, first of all, the MAPE value of the GRA-LSTM combined model established in this paper is 7.3, and the prediction performance of this model is better than the other seven structural methods. Secondly, the area demand for landfills in Beijing shows an upward trend. At last, this paper put forward relevant suggestions to achieve sustainable urban development and deal with the increase in the MSW generation and the demand for landfills., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Environmental degradation, often evidenced by haze, has not only increased the cost of China's economic development, but its unfair distribution among regional development, social hierarchy, and generations has also reduced quality of life. Hence, this study uses cross-sectional data from Didi, a Chinese ridesourcing service company, from 2017 to study the impact mechanism of shared mobility on haze. First, it applies the generalized spatial two-stage least squares model after controlling for urban economic, geographic, transportation, meteorological, and policy variables. We then use urbanization depth (urban agglomeration) and breadth (urban sprawl) variables, which represent the intensity and scope of human activities, respectively, as mediators to test the transmission mechanism from shared mobility to haze. Finally, differences based on urban heterogeneity were tested in the end. The study finds that the scale of ridesourcing and haze show a significant U-shaped relationship: the initial development of ridesourcing has a significant effect on reducing haze, but will then intensify haze as it develops to scales such as those of Beijing and Shenzhen. Moreover, the depth of urbanization is the main transmission mechanism of haze. This conclusion is verified in Tier 3 cities and above; however, the transmission mechanism in Tier 4 and Tier 5 cities is not obvious, indicating that the scale of ridesourcing should be compatible with the scale of urban development. Therefore, the design of emission reduction policies should be considered from the perspective of urban agglomeration., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Public participation in environmental management (PPEM) in China has become increasingly prominent; thus, investigating the factors that underlie participation by the Chinese public in environmental management is important. To this end, we adopted unique data for PPEM, which was measured based on environmental complaints logged by the telephone hotline set up by the Ministry of Ecology and Environment of China. We observed that PPEM greatly varied from one city to another, indicating significant spatial heterogeneity. In addition, complaints were mainly concentrated in four large regions, namely, the North China Plain, the Yangtze River Delta, the Pearl River Delta, and the Chengdu-Chongqing urban agglomeration. Next, a newly developed spatial heterogeneity analysis method, namely, geographical detector, was applied to investigate the driving factors of PPEM. From the factor detector analysis results, we confirmed that the economic level, energy consumption, urban population, college-educated population, wastewater, environmental risk, SO 2 emissions, and PM 2.5 concentrations were the dominant factors that caused citizens to voice environmental complaints. In addition, we noticed that moderately developed cities were the leading risk areas, which indicated that these cities had serious environmental pollution problems and their citizens actively voiced complaints. As economies continue to grow, the populations in these cities are projected to become more aware of environmental quality and will implement stricter regulations to protect the environment and lower complaints. Moreover, the interaction detector analysis results revealed that the interaction of urban and college-educated populations with other factors played more important roles in affecting PPEM., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

With the rapid growth of foreign direct investment (FDI), PM 2.5 pollution in Chinese cities is increasing. Based on panel data for 271 Chinese cities from 2003 to 2016, this paper uses the dynamic spatial fixed-effects Durbin model to analyze the correlation between FDI and PM 2.5 pollution and the effect of FDI on urban PM 2.5 concentrations, as mediated by industrial structure transformation, which is clarified using Stata/SE 16.0. The results showed that PM 2.5 pollution in China has significant spatial spillover effects, and the pollution haven hypothesis is applicable to Chinese cities. The industrial structure partially mediates the relationship between FDI and PM 2.5 . This paper proposes that local governments should promote the market-oriented reform of FDI to create a more convenient, legalized, and international environment for FDI and innovate the governance philosophy of only reducing the existing emissions. A top-level design and sound market supervision system of PM 2.5 control are also needed.

In this study, the rainfall, pH, conductivity, and ionic component data for Guilin from 2015 to 2017 were analyzed. Specifically, the relationship between the pH value of the rainfall, the change of each ion in the rainfall, and the primary ion sources was examined. The main results obtained were as follows. During the 3-year study period, the average annual pH value of Guilin was 5.45 and exhibited a downward trend. The seasonal variation of rainfall acidity was pronounced, with high pH values and low frequencies of acid rain in summer, and low pH values and high frequencies of acid rain in winter. From 2015 to 2017, the relative order of the average concentrations of the ionic components in the rainfall was SO 4 2-  > NO 3 -  > Ca 2+  > Cl -  > NH 4 +  > Na +  > K +  > Mg 2+  > F - , the annual average concentration of each ionic component displayed a downward trend, and seasonal changes were obvious. Only NH 4 + showed an upward trend in rainfall. The (SO 4 2- )/(NO 3 - ) ratio was basically < 3 and manifested a downward trend; (Ca 2+ )/(NH 4 + ) rose sharply in August and September each year. Using correlation analysis and enrichment factor analysis, it was concluded that the rainfall in Guilin is mainly affected by SO 2 , NO x , and NH 3 , with the geological conditions in the karst area also contributing a certain amount to the rainfall acidity. Calculating the enrichment factor revealed that most of the Ca 2+ came from a crustal source; half the Mg 2+ came from the ocean and half came from the crust; and most of K + and Cl - originated from the ocean. Human activities contributed most of the SO 4 2- and NO 3 - in the rainfall., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The total amount of drug waste is expanding significantly as populations age and societies become wealthier. Drug waste is becoming a problem for health and the environment. Thus, how to reduce and effectively dispose of drug waste is increasingly becoming an issue for society. This study focuses on household drug management, which involves five sub-practices: selection, purchasing, using, storing, and disposing of drugs. A questionnaire survey was conducted in a second-tier Chinese city that reveals both problems and opportunities in these five sub-practices. The results show that consumers are aware of significant issues with regard to the safe and effective use of drugs as well as with regard to proper ways of disposing of and recycling drugs. Moreover, our analysis reveals promising opportunities for addressing these issues by developing novel services based on the idea of connecting the five involved sub-practices of household drug management. Connecting and adjusting practices in this manner can be seen as an important factor in reducing drug waste and pharmaceutical pollutants.

The US Environmental Protection Agency has listed 16 polycyclic aromatic hydrocarbons (PAHs) for priority control. Soil samples from Xiangxi Bay in the Three Gorges Reservoir Area (the water fluctuation zone, WLFZ; upper edge of water fluctuation zone, UEWLFZ; sediments) were analyzed for the concentration of these PAHs, using high performance liquid chromatography (HPLC). The results showed that the soil samples of Xiangxi Bay could be ranked, based on the concentration of PAHs, in the following order:UEWLFZ>WLFZ>sediment. The composition of PAHs varied from the three regions, with 3- and 4-ring PAHs dominating in sediments and 4- and 5-ring PAHs dominating in soil from the WLFZ and UEWLFZ. The composition of PAHs in soil from the WLFZ exhibited a higher coefficient of variation and a weaker correlation with the composition of PAHs in soil from the UEWLFZ and sediment. Soil from the three regions showed varying seasonal distributions of PAHs, which is closely related to the quantity and types of energy consumption in each season. PAHs in sediment from sites at the same altitude showed no evident differences, whereas WLFZ and UEWLFZ soil had higher levels of PAHs at the sites near Xiakou Town and the Yangtze River Estuary. Isomer ratio analysis showed that the sources of PAHs in Xiangxi Bay vary between seasons and regions, with incomplete combustion of fossil fuels and biomass forming the main sources in the soil of Xiangxi Bay. The lifetime carcinogenic risk assessment shows that PAHs in sediment, WLFZ, and UEWLFZ have a potential risk to human through ingestion and dermal contact, with PAHs in the soil of UEWLFZ posing the highest carcinogenic risk. The results provide a theoretical reference for the prevention and control of contamination by PAHs in Xiangxi Bay of the Three Gorges Reservoir area.

Understanding the impact on the thermal effect by urbanization is of great significance for urban thermal regulation and is essential for determining the relationship between the urban heat island (UHI) effect and the complexities of urban function and landscape structure. For this purpose, we conducted case research in the metropolitan region of Beijing, China, and nearly 5000 urban blocks assigned different urban function zones (UFZs) were identified as the basic spatial analysis units. The seasonal land surface temperature (LST) retrieved from remote sensing data was used to represent the UHI characteristics of the study area, and the surface biophysical parameters, building forms, and filtered landscape pattern metrics were selected as the urban landscape factors. Then, the effects of urban function and landscape structure on the UHI effect were examined based on the optimal results of the ordinary least squares and geographically weighted regression models. The results indicated that (1) Significant spatiotemporal heterogeneity of the LST was found in the study area, and there was an obvious temperature gradient with "working-living-resting" UFZs. (2) All types of urban landscape factors showed a significant contribution to the seasonal LST, in the order of surface biophysical factors > building forms > landscape factors; however, their contributions varied in different seasons. (3) The major contributing factors showed a certain difference due to the variation of urban function and landscape complexity. This study expands the understanding on the complex relationship among urban landscape, function, and thermal environment, which could benefit urban landscape planning for UHI alleviation., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Extensive urbanization leads to the degradation of vegetation, which aggravates the deterioration of many ecological environments. However, the research on the impact of urbanization on vegetation change mainly focuses on cities. But the research on urban agglomeration is relatively scarce. The impact of urbanization on vegetation is explored by quantifying the changes in construction land and normalized difference vegetation index (NDVI) in China's urban agglomerations from 2000 to 2018. Results showed that in China, 72.73% of the regional NDVI presented a significant increasing trend, and 2.05% of the regional NDVI presented a significant downward trend. Vegetation degradation occurred in urban areas, but there was an improvement in vegetation in the urban centers of 2000. In urban agglomerations, the shift of the center of gravity of construction land can affect the direction of the transfer of NDVI cold spots or hot spots. Urbanization intensity in most urban agglomerations was negatively correlated with vegetation cover and showed a downward trend along the intensity gradient. However, NDVI in areas covered by complete vegetation showed an upward trend. Based on these findings, we suggest that vegetation protection and restoration should be strengthened, and effective urban landscape planning should be carried out to promote vegetation greening., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Though a definitive link between small colony variants (SCVs) and implant-related staphylococcal infections has been well-established, the specific underlying mechanism remains an ill-explored field. The present study analyzes the role SCVs play in catheter infection by performing genomic and metabolic analyses, as well as analyzing biofilm formation and impacts of glycine on growth and peptidoglycan-linking rate, on a clinically typical Staphylococcus epidermidis case harboring stable SCV, normal counterpart (NC) and nonstable SCV. Our findings reveal that S. epidermidis stable SCV carries mutations involved in various metabolic processes. Metabolome analyses demonstrate that two biosynthetic pathways are apparently disturbed in SCV. One is glycine biosynthesis, which contributes to remarkable glycine shortage, and supplementation of glycine restores growth and peptidoglycan-linking rate of SCV. The other is overflow of pyruvic acid and acetyl-CoA, leading to excessive acetate. SCV demonstrates higher biofilm-forming ability due to rapid autolysis and subsequent eDNA release. Despite a remarkable decline in cell viability, SCV can facilitate in vitro biofilm formation and in vivo survival of NC when co-infected with its normal counterparts. This work illustrates an intriguing strategy utilized by a glycine-auxotrophic clinical S. epidermidis SCV isolate to facilitate biofilm-related infections, and casts a new light on the role of SCV in persistent infections., (© 2021. The Author(s).)

Waste classification is regarded as one of the most important strategies for waste management, and its success depends on the active participation of the public. Based on the theory of planned behavior (TPB) and attitude-behavior-condition (A-B-C) theory, this research investigated the key factors affecting residents' domestic waste classification intention (WCI) and waste classification behavior (WCB), and explored the moderating effects of three external factors including infrastructure (INF), government publicity (GP), and incentive measures (IM) on the intention-behavior relationship. The valid data were collected from 584 residents via conducting a face-to-face interview in Chengdu, a pilot city of waste classification in China, and analyzed by using the structural equation model (SEM). Results showed that residents' WCI and WCB had a significant discrepancy with the average values of 4.07 and 2.81, respectively. Attitude (AT), perceived behavior control (PBC) and classification knowledge (CK) were significantly related to residents' WCI, with AT (β = 0.65, P < 0.001) having the greatest direct impact. Meanwhile, CK and INF had a stronger impact on the WCB than WCI. GP indirectly affected WCB through the intermediary effect of CK. In addition, INF and GP had a positively moderating effect on residents' waste classification intention-behavior relationship and can facilitate the intention-behavior conversion. By contrast, IM failed to promote the conversion of residents' classification intention into behavior, and had no direct significant influence on residents' WCB. Finally, some relevant policy suggestions were put forward for the new pilot cities of waste classification in China., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Increasing urban heat island and global warming have aroused serious thermal environmental problems and even harm people's thermal health. Because of the importance in people's daily life, a commercial pedestrianized block represents a symbol of a city or metropolis; therefore, focusing the attention on the thermal environment in such regions is very necessary. Most of the researches on the urban thermal environment are calculated by remote sensing data; limited by the low spatial resolution of remote sensing image, it may not obviously reflect the true thermal environment of the research site, especially in some microscale regions. Based on this, the new software ENVI-met is developed to research the thermal environment and forecast people's thermal sensation in a microscale region. Therefore, the objective of this study aims at conducting field measurement and numerical simulation to assess the thermal environment of a typical commercial pedestrianized space in southern China and assess the different urban design parameters in ameliorating the urban heat island effect. Our final results demonstrate a quantitative evidence for establishing a comprehensive standard for improving the thermal environment in a microscale region, and this study also can be a supplementary in the research field about improving thermal health., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)