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With the rapid development of ports in the world today, the ecological environment pollution of port cities is becoming more and more serious. How to coordinate the port industry and the urban environment is an urgent problem to be solved. This article proposes a system to evaluate the coordination between port industry chain development and the urban ecological environment by taking Shanghai Port as an example. The Principal Component Analysis (PCA) method was applied to calculate the weights of various indexes, then the Coupling Coordination Degree Model (CCDM) was adopted to systematically study the coordination relationship between port industry development and the urban ecological environment. Our research finds the coupling coordination degree between Shanghai Port's economic development and the urban ecological environment shows an overall upward trend, changing from severely misaligned in 2000 (0.125) to barely coordinated in 2019 (0.691). Shanghai has achieved some results in constructing the ecological environment and green port, but there is still much room for improvement. Shanghai port needs to strengthen container transportation, enhance energy conservation and emission reduction, and vigorously promote the development of a green port. This study will provide a basis and reference for relevant institutions, government departments, and policymakers to formulate scientific and effective green port industry chain development strategies., 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.)

The world is undergoing an unprecedented trend of fast urbanization, which causes a range of socio-environmental consequences, one of which is shrinking cities and towns (SCT). SCT refer to the cities or towns that are experiencing population decline and economic downturn. In the existing literature, there have been numerous studies on SCT; however, there is a lack of study which investigates its knowledge domains. Therefore, this paper aims to conduct a scientometric analysis to achieve an outline of the SCT research status. Through the procedures of literature search and screening, a total of 716 SCT-related studies were extracted from the Scopus. The VOSviewer software system program was then utilized to visualize the present SCT-related studies. The visualization results revealed that the journal of Sustainability made significant contributions to the SCT research in terms of relevant publications. In addition, Haase, Annegret received the most co-citations, and was also the most productive author in this field. Furthermore, it was identified that current SCT research is mainly conducted in developed countries. Through the analysis of keywords, the emerging research topics were revealed. Discussions were further made from the perspectives of prevailing research methods, evaluation criteria, and solutions for SCT problems.

With the continuous improvement in the integration of urban agglomeration, a multi-functional, socialized, and complex dynamic system, effective prevention and control of emergent public health events have become increasingly important. Based on the Public-Health Vulnerability-Assessment-System of Urban Agglomeration (PVUA), the temporal and spatial differentiation characteristics of vulnerability in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) for the period of 2015-2019 are explored, and the vulnerable cities to public health events are identified in this area. The results can be summarized as follows: (1) The overall vulnerability to public health events in GBA decreases in the investigated period. (2) In the temporal dimension, accompanied by social and economic development, the sensitivity to public health events increases in GBA, and the coping capacity change from stable fluctuation to rapid improvement. (3) From the spatial dimension, the sensitivity level in GBA is low in the west, relatively high in the middle, and high in the southeast; the coping capacity is high in the southeast and low in the northwest; the collaborative governance capacity presents a spatial pattern of being low in the south and high in the north. (4) In the period of study, the vulnerability to public health events in Guangzhou and Jiangmen is stable at the lowest level, while that in Zhaoqing, Foshan, and Hong Kong SAR (Special Administrative Region) gradually reduces; the vulnerability in Shenzhen, Zhuhai, and Dongguan is fluctuating, and that in Huizhou, Zhongshan, and Macao SAR is continually maintained at a higher and the highest level., 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 © 2022 Cui, Chen, Shen, Zhang, Liu and Zhou.)

Spatial conflicts are formed in the process of urbanization and become the primary drivers of urban ecological and environmental problems. The defining trait of a spatial conflict is the occupation of ecological or agricultural spaces by construction spaces. This work presents a classification scheme for spatial conflicts in China, including source-area conflicts, corridor conflicts, safety conflicts, and farmland conflicts. Also, it constructs a model for the determination of spatial conflicts and conflict intensity using diagrammatic method. Based on a case study performed using our methods on Shenzhen, we proposed a timeline and policy roadmap for the resolution of spatial conflicts in Shenzhen according to the severity and characteristics of spatial conflicts in the city. The results show that the total spatially conflicted area of Shenzhen is 10.57 km 2 , and the percentage of construction land-use in these areas is 1.37%. The spatial conflicts are mainly source-area or corridor conflicts, and minor conflicts account for approximately 60% of the total conflicted area. Most of the spatial conflicts are either "easy to resolve" or "moderately easy to resolve". Overall, in terms of the severity of spatial conflict, Shenzhen remains at the "stable and under control" level. Considering the primary aim of spatial conflict resolution is to revert built-up lands into urban green spaces, we proposed a timeline for the resolution of spatial conflicts in Shenzhen over the next 15 years, as well as a system of supporting policies. The results of this study shall serve as a guide for the optimization of urban spatial structures and the promotion of sustainable urban development., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Exposure to green spaces contributes to residents' physical and mental health and well-being. The equitable allocation of green space has also become an increasingly important issue for society and the government. This study takes 3281 communities in Shenzhen as the analysis units. Using web crawlers, semantic segmentation based on deep learning, web map path planning and entropy weighting methods, four types of residents' daily green exposure indicators are calculated, including community green space ratio, green view index (GVI), park accessibility, and the weighted composite green exposure index. The results reveal inequalities in the level of green exposure in Shenzhen's communities across economic classes, mainly in GVI and comprehensive green exposure. We also found that the level of composite green exposure is relatively stable; however, green space ratio attainment levels for newer communities are increasing and GVI and park accessibility attainment levels are decreasing. Finally, among the newly built communities: compared to the low-income level communities, the high-income level communities have a significant advantage in green space, but the mid-income level communities do not have such an advantage. The main findings of this study can provide policy implications for urban green space planning, including the need to prioritize the addition of public green space near older communities with poor levels of green exposure, the addition of street greenery near communities with poor levels of composite green exposure, and ensuring that parks have entrances in all four directions as far as possible.

Exposure to inhalable particulate matter pollution is a hazard to human health. Many studies have examined the in-transit particulate matter pollution across multiple travel modes. However, limited information is available on the comparison of in-transit exposure among cities that experience different climates and weather patterns. This study aimed to examine the variations in in-cabin particle concentrations during taxi, bus, and metro commutes among four megacities located in the inland and coastal areas of China. To this end, we employed a portable monitoring approach to measure in-transit particle concentrations and the corresponding transit conditions using spatiotemporal information. The results highlighted significant differences in in-cabin particle concentrations among the four cities, indicating that PM concentrations varied in an ascending order of, and the ratios of different-sized particle concentrations varied in a descending order of CS, SZ, GZ, and WH. Variations in in-cabin particle concentrations during bus and metro transits between cities were mainly positively associated with urban background particle concentrations. Unlike those in bus and metro transit, in-cabin PM concentrations in taxi transit were negatively associated with urban precipitation and wind speed. The variations in particle concentrations during the trip were significantly associated with passenger density, posture, the in-cabin location of investigators, and window condition, some of which showed interactive effects. Our findings suggest that improving the urban background environment is essential for reducing particulate pollution in public transport microenvironments. Moreover, optimizing the scheduling of buses and the distribution of bus stops might contribute to mitigating the in-cabin exposure levels in transit. With reference to our methods and insights, policymakers and other researchers may further explore in-transit exposure to particle pollution in different cities.

This study investigated atmospheric changes that occurred due to changes in energy production and consumption before and during the COVID-19 pandemic. We analyzed nitrogen dioxide (NO 2 ), aerosol optical depth (AOD), and rainfall patterns to understand the associated changes in emissions, especially from the power generation sector, before (2018 and 2019) and during the lockdown of 2020 across Pakistan. Regression analysis indicated a strong association between energy production by thermal power plants and tropospheric NO 2 concentrations. Notably, a comparison between emission sources showed that the NO 2 emissions from a single thermal power plant were equivalent to the emissions from a major city. During the lockdown, we observed a 40% reduction in NO 2 emissions from coal-based power plants and a 30% reduction in mega- and major cities compared to the same retro in 2019. We also observed an approximate 25% decrease in AOD in the industrial and energy sectors, although no major decrease was obvious in the cities. Rainfall contributed to reducing the NO 2 concentrations during monsoon season across all power plants in Pakistan, whereas it did not significantly correlate with AOD. The findings highlight the need for appropriate management and use of renewable energy in the industrial sector and transportation systems. Future research could estimate the environmental and public health costs linked to pollution originating from thermal energy production and poor transportation infrastructure., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Individual, meteorological, and environmental factors are associated with cognitive function in older age. However, little is known about how meteorological and environmental factors interact with individual factors in affecting cognitive function in older adults. In the current study, we used mixed effects models to assess the association of individual, meteorological, and environmental factors with cognitive function among older adults in urban areas. Data from 2623 adults aged 60 to 91 years from 25 provinces (or autonomous regions/municipalities) from the China Family Panel Studies (CFPS) were used. We used the memory test in CFPS to measure memory function, while meteorological data from the daily climate data set of China's surface international exchange stations, and the traffic and greening data compiled by the National Bureau of Statistics (NBS) of China, were used to assess meteorological and environmental factors. The ICC of the empty model indicated that 7.7% of the variation in memory test scores for the older adults was caused by provincial characteristics. Results showed that the temperature and relative humidity of provinces moderated the effect of gender on the memory function for the older urban adults. Specifically, in the high temperature areas, memory scores for females were higher than those of males, and in the middle humidity areas, memory scores were also higher for the females than those of males. This study explained how meteorological and environmental factors played roles in influencing demographic factors on memory function among older adults. Further research is needed to better define the role and potential mechanism of this moderation.

To optimize the accessibility algorithm and quantify the potential relationship between human development index and traffic comprehensive accessibility system, this paper analyzed the spatial distribution pattern of urban accessibility and human development index of highway, railway, and aviation transportation systems using data on highway, railway, and aviation schedules based on GIS spatial analysis method. Furthermore, the coupling degree between human development index and accessibility and its influence mechanism on the city level in China were explored based on the super-efficiency data envelopment analysis model. Results showed as follows: (1) Spatial distribution of human development index from high to low was gradually changing from east to west. The spatial distribution of urban accessibility of the three traffic systems had an evident "Hu Huanyong Line" effect. (2) The coordination degree of urban accessibility and human development index spread in a ladder mode. High coordination of cities in North and East China and the central Yangtze River region forms the spatial distribution of urban development circles connecting an urban development belt. (3) Railway connectivity and control value were highly sensitive to human development index in cities where serious imbalance between accessibility and human development index. Highway connectivity and control value were highly sensitive to human development index in cities where high coordination between accessibility and human development index. The results would provide scientific references for spatial planning of transportation, economic, and social development of cities and coordinated development of urban agglomeration in China., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction and Objective: Vaccinations programs on 3-17 years aged children in China have been launched in some cities since July 2021; and comparative evaluations are important to push the programs forward. Therefore, this study is conducted to explore the COVID-19 vaccine hesitancy and it predictors among Chinese parents of 3-17 years aged children; and their willingness to vaccinate their child/children., Material and Methods: A cross-sectional study was conducted based on the online survey; and 3484 participants were recruited in health centers of Shenzhen, China., Results: The prevalence of COVID-19 vaccine hesitancy was 20.7% among Chinese parents of 3-17 years aged children; and 2976 participants (89.0%) were reported to be willing or very willing to accept a COVID-19 vaccine for their child/children. Perceived trust degree of a COVID-19 vaccine (OR: 0.766), and perceived effectiveness of a COVID-19 vaccine (OR: 0.455) were negatively associated with vaccine hesitancy. Perceived risk degree of a COVID-19 vaccine (OR: 1.485) positively predicted vaccine hesitancy. Parents with a higher educational level (OR: 0.518) and working in public institution (OR: 0.741) had a lower level of vaccine hesitancy; whereas, parents with liberal professionals had a higher level of vaccine hesitancy (OR: 1.378)., Conclusions: These findings indicated that Chinese parents of 3-17 years aged children in Shenzhen City had a higher level of COVID-19 vaccine acceptability, compared with adults in Western counties. The significant factors of perceived trust degree, effectiveness, and risk degree of a COVID-19 vaccine, parents' educational level and occupation could predict COVID-19 vaccine hesitancy. The research results can be useful in supporting the development of effective and targeted children COVID-19 vaccination campaigns in China and worldwide.

Background: Motivated by the need for precise epidemic control and epidemic-resilient urban design, this study aims to reveal the joint and interactive associations between urban socioeconomic, density, connectivity, and functionality characteristics and the COVID-19 spread within a high-density city. Many studies have been made on the associations between urban characteristics and the COVID-19 spread, but there is a scarcity of such studies in the intra-city scale and as regards complex joint and interactive associations by using advanced machine learning approaches., Methods: Differential-evolution-based association rule mining was used to investigate the joint and interactive associations between the urban characteristics and the spatiotemporal distribution of COVID-19 confirmed cases, at the neighborhood scale in Hong Kong. The associations were comparatively studied for the distribution of the cases in four waves of COVID-19 transmission: before Jun 2020 (wave 1 and 2), Jul-Oct 2020 (wave 3), and Nov 2020-Feb 2021 (wave 4), and for local and imported confirmed cases., Results: The first two waves of COVID-19 were found mainly characterized by higher-socioeconomic-status (SES) imported cases. The third-wave outbreak concentrated in densely populated and usually lower-SES neighborhoods, showing a high risk of within-neighborhood virus transmissions jointly contributed by high density and unfavorable SES. Starting with a super-spread which considerably involved high-SES population, the fourth-wave outbreak showed a stronger link to cross-neighborhood transmissions driven by urban functionality. Then the outbreak diffused to lower-SES neighborhoods and interactively aggravated the within-neighborhood pandemic transmissions. Association was also found between a higher SES and a slightly longer waiting period (i.e., the period from symptom onset to diagnosis of symptomatic cases), which further indicated the potential contribution of higher-SES population to the pandemic transmission., Conclusions: The results of this study may provide references to developing precise anti-pandemic measures for specific neighborhoods and virus transmission routes. The study also highlights the essentiality of reliving co-locating overcrowdedness and unfavorable SES for developing epidemic-resilient compact cities, and the higher obligation of higher-SES population to conform anti-pandemic policies., (© 2022. The Author(s).)

The availability of environmental emission data is critical in evaluation of countries' ecological security and the implementation of environmental management. However, access to environmental emission data at the county level is not provided by statistical publications and bulletins. Therefore, in this paper, we develop two novel data downscaling models, an environmental Kuznets curve downscaling model (EKCDM) and a scale model (SM), to obtain county-level environmental emission data. The EKCDM relies on the EKC hypothesis and the assumption that the same model applies across scales, whereas the SM depends on the assumption that the share of a region's environmental pollution is equivalent to its share of economic output. Subsequently, environmental emission data above the county scale can be obtained through model transformation and simple calculations. By verifying and analyzing the official data with the one obtained through downscaling at municipal level and above, we verify the feasibility of the models, after which we apply the models to extrapolate information on the industrial waste of the counties of Dongguan city in Guangdong Province, China. We find that the EKCDM should be given priority in most cases, especially for the quadratic parameter model, and that the SM can be adopted when per capita gross domestic product differs greatly between adjacent levels of administrative units. In general, scholars can synthesize the characteristics of these two models, and obtain more accurate data by supplementing and verifying one with the other. Compared with other downscaling methods, our methods require far less data and the concepts are easily understood, which makes them more feasible and increases applicability. This study provides scholars with powerful tools to explore the relationship between industrial pollution and economic development in depth by obtaining industrial waste data at the county scale, thereby supporting scientific research and policy design., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Empirical studies of urban expansion have increased rapidly in recent decades worldwide. Previous studies mainly focused on cities in China, the United States or African countries, with Brazilian cities receiving less attention. Moreover, such studies are rare in purpose-built cities. Taking the urban expansion from scratch (1960) to urban agglomeration (2015) in the Federal District of Brazil (FDB) as an example, this study aims to quantify the magnitude, patterns, modes, types and efficiency of urban land expansion and attempts to reveal some implications within sustainable urban expansion thinking. Annual expansion, landscape metrics, local Moran's I index, area weighted mean expansion index, and land-use efficiency were computed. The suitability of diffusion-coalescence theory and the impact of population growth and urban development policies on urban expansion were discussed. Urban land continuously expanded and became more fragmented during 1960-2015, which mainly occurred in SSW and WSW directions. Urban land evolved in a polycentric way. Edge expansion was identified as the stable contributor, and the importance of infilling and spontaneous growth alternated. Urban expansion in this region supported the diffusion-coalescence theory. Population growth promoted urban expansion, and the creation of peripheral urban nuclei and their development were associated with the urban expansion and the changes in urban land structure. This study adds new empirical evidence of urban expansion to Brazil urbanization, and compact urbanization, population control, and efficient urban land use should be considered in the future.

Continuing urbanization and significant improvement of lifestyle have ushered in high demand for building floor area, inevitably leading to a rapid increase of interior decoration and renovation activities, which in turn produce a massive quantity of decoration and renovation waste (DRW). However, like many other countries with unremitting demand for building space and infrastructure, China has failed to attach adequate attention to DRW management. Using the yield-per-area method and life cycle assessment approach, this study aims to characterize the generation, flows, management and environmental impacts of DRW from commercial housing in nine cities in the Greater Bay Area (GBA), a highly developed economic zone in China. The results show that the production of DRW in the GBA increased from 0.16 million metric tons (Mt) in 1999 to 2.6 (±10%) Mt in 2018, with an annual growth rate of 16%. Ninety-five percent of the DRW is directly disposed of via simple landfilling. Although the recycling rate is relatively low, it still generated a benefit of 119,000 tons CO 2 eq mitigation in 2018. According to scenario-based analysis, improving the recycling rate and encouraging the use of prefabricated decoration could go a long way toward tackling the DRW problem. These findings can help reveal the full impacts of DRW in the GBA, and also provide a reference for other cities to take action., 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.)

Objective measurement of the supply-demand of ecosystem services (ESs) has received increasing attention from recent studies. It reflects the relationship between green spaces and human society. However, these studies rarely assess the mountainous cities. To fill this gap, this study takes a typical mountainous city as a research case to reveal the supply-demand relationship of ecosystem services, then development and management strategies are proposed for different districts according to their spatial differentiation characteristics. Results shows that: (1) there are differences of ESs supply between each district, and supply from Banan District is significantly higher than others. (2) The demands for ES also vary widely, which are higher in the core urban areas. (3) There are different degrees of imbalance between supply and demand in each district. We classified green spaces into four types based on their supply-demand characteristics, and optimization strategies are proposed. We found that most of the districts are lack of ES supply while there is a relatively high demand for ES in Chongqing, and the balance of supply and demand between different districts varies greatly. Our study indicates that targeted urban green spaces strategies for different districts must be considered to adequately optimize ES in mountainous cities.

This study investigated the environmental spatial heterogeneity of novel coronavirus (COVID-19) and spatial and temporal changes among the top-20 metropolitan cities of the Asia-Pacific. Remote sensing-based assessment is performed to analyze before and during the lockdown amid COVID-19 lockdown in the cities. Air pollution and mobility data of each city (Bangkok, Beijing, Busan, Dhaka, Delhi, Ho Chi Minh, Hong Kong, Karachi, Mumbai, Seoul, Shanghai, Singapore, Tokyo, Wuhan, and few others) have been collected and analyzed for 2019 and 2020. Results indicated that almost every city was impacted positively regarding environmental emissions and visible reduction were found in Aerosol Optical Depth (AOD), sulfur dioxide (SO 2 ), carbon monoxide (CO), and nitrogen dioxide (NO 2 ) concentrations before and during lockdown periods of 2020 as compared to those of 2019. The highest NO 2 emission reduction (~ 50%) was recorded in Wuhan city during the lockdown of 2020. AOD was highest in Beijing and lowest in Colombo (< 10%). Overall, 90% movement was reduced till mid-April, 2020. A 98% reduction in mobility was recorded in Delhi, Seoul, and Wuhan. This analysis suggests that smart mobility and partial shutdown policies could be developed to reduce environmental pollutions in the region. Wuhan city is one of the benchmarks and can be replicated for the rest of the Asian cities wherever applicable., (© 2021. The Author(s).)

Wastewater-based epidemiology (WBE) has been used extensively around the globe to provide information on illicit drug consumption. In China, most WBE studies to date only include a limited number of samples per catchment, making it difficult to derive any temporal consumption patterns. This study addresses this knowledge gap by identifying the temporal consumption trends of nine drugs in a Chinese megacity using WBE over a one-year period. Daily influent samples (n = 279) were collected from a wastewater treatment plant serving ~500,000 residents. All target drugs showed similar levels of consumption throughout the week. These findings were different to previous WBE studies in developed countries, where amphetamine-type drugs have shown higher consumption on weekends than during the week. Such a difference could be due to the users' demographics and behaviors as reported in previous surveys and warrant more research to help formulate appropriate drug control policies in China. Our study also observed that declining methamphetamine and ketamine consumption between 2012 and 2018, while consumption of MDMA and methadone were stable over the same period., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Construction and demolition waste (C&DW) has become part of the largest waste stream globally and many cities are facing the shortage of management capability to treat C&DW. These cities seek to transport their C&DW to their neighbor cities for recycling or landfilling, which is recognized as the cross-regional management of C&DW. However, there were few studies to investigate the mechanism of cross-regional mobility in C&DW field. This study developed a model to evaluate the self-fulfillment degree of C&DW management capability at regional level based on the Triple-balance theory. Guangdong-Hong Kong-Macao Greater Bay Area (GBA) was selected as the study case, and the data was collected through on-site surveys, expert interviews, and desktop surveys. The results showed that the self-fulfillment degree of C&DW management capability of the cities, such as Guangzhou, Zhuhai, Foshan, Dongguan, Jiangmen, and Zhaoqing was high, which meant these cities could well manage the C&DW generated within the regions under current situation. The self-fulfillment degree of management capability of Macao, Huizhou, and Zhongshan was evaluated as medium; while the indicators of Hong Kong and Shenzhen fell into low category, which meant they needed to transport surplus C&DW to other cities for further treatment. The research is significant as it provides an innovative evaluation model considering the cross-regional mobility for C&DW management performance assessment. Besides, the findings could assist the waste management sectors to plan the C&DW treatment facilities in GBA, while other cities could also benefit from this study regarding to the cross-regional mobility management of C&DW., (Copyright © 2021. Published by Elsevier Ltd.)

China produced and consumed a large amount of per- and polyfluoroalkyl substances (PFASs). whose persistency and possible toxicity to organisms have raised public health concerns. Analyzing influent wastewater could help to assess the composition and mass load of PFASs discharged into a wastewater treatment plant (WWTP) from its catchment. In this study, we analyzed 27 PFASs in wastewater samples collected from 42 WWTPs across China in 2014 and 2016. Results indicated that perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS) were the most common PFASs in wastewater. Population normalized mass loads of PFOA and PFOS were higher in Eastern China than in the other three regions, possibly due to their higher usage. Although the concentrations of PFASs in Central and West areas were showed lower than in East area, Wuhan (in Central area) and Lanzhou (in West area) were hotspots of PFASs pollution because of their industry structure. Population density and per capita Gross Domestic Product (GDP) have positive correlations with the concentration of PFBA, PFOA, PFHxA, and ∑PFASs in wastewater. The estimated annual release of PFASs to WWTPs in our study is much lower than the total emission to the environment. Our results suggest that although there was some reduction in the production volume, certain legacy PFASs were still released into wastewater and their composition and concentration vary among WWTPs., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The first human infected with the Covid-19 virus was traced to a seafood market in Wuhan, China. Research shows that there are comparable types of viruses found in different and mutually distant areas. This raises several questions: what if the virus originated in another location? How will future waves of epidemics behave if they originate from different locations with a smaller/larger population than Wuhan? To explore these questions, we implement an agent-based model within fractal cities. Cities radiate gravitational social attraction based on their Zipfian population. The probability and predictability of contagion events are analyzed by examining fractal dimensions and lacunarity. Results show that weak gravitational forces of small locations help dissipate infections across country quicker if the pathogen had originated from that location. Gravitational forces of large cities help contain infections within them if they are the starting locations for the pathogen. Greater connectedness and symmetry allow for a more predictable epidemic outcome since there are no obstructions to spreading. To test our hypothesis, we implement datasets from two countries, Sierra Leone and Liberia, and two diseases, Ebola and Covid-19, and obtain the same results., (© 2021. The Author(s).)

Storm surge is a natural disaster, often causing economic damage and loss of human life in the coastal communities. In recent decades, with more people attracted to coastal areas, the potential economic losses resulted from storm surges are increasing. Therefore, it is important to make risk assessments to identify areas at risk and design risk reduction strategies. However, the quantitative risk assessment of storm surge for coastal cities in China is often difficult due to the lack of adequate data regarding the building footprint and vulnerability curves. This paper aims to provide a methodology for conducting the quantitative risk assessment of storm surge, estimating direct tangible damage, by using Geographical Information System (GIS) techniques and open data. The proposed methodology was applied to a coastal area with a high concentration of petroleum industries in the Daya Bay zone. At first, five individual typhoon scenarios with different return periods (1000, 100, 50, 20, and 10 years) were defined. Then, the Advanced Circulation model and the Simulating Waves Nearshore model were utilized to simulate storm surge. The model outputs were imported into GIS software, transformed into inundation area and inundation depth. Subsequently, the building footprint data were extracted by the use of GIS techniques, including spatial analysis and image analysis. The layer containing building footprints was superimposed on the inundation area layer to identify and quantify the exposed elements to storm surge hazard. Combining the exposed elements with their related depth-damage functions, the quantitative risk assessment translates the spatial extent and depth of storm surge into the estimation of economic losses. The quantitative risk assessment and zonation maps for sub-zones in the study area can help local decision-makers to prioritize the sub-zones that are more likely to be affected by storm surge, make risk mitigation strategies, and develop long-term urban plans., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Increasing amounts of municipal solid waste (MSW) has gained widely concern on reduction, utilization and minimizing environmental impacts associated with waste management. Life cycle assessment (LCA) has been used to evaluate total environmental impact of municipal waste management (MSWM) options in strategy-planning and decision-making process. The exiting LCA studies have covered a large range of detailed focus from waste treatment technology to applied modelling methods in LCA of MSWM, yet an important concern for stakeholders, the relationship between practical management strategies and their LCA results, has not been comprehensively summarized. This paper reviews recent LCA studies focusing on MSWM system in 45 cases from both developing and developed regions to promote evolution of the MSWM system through modification of waste management strategies. Selected literatures conducted LCA with system boundary covering the whole MSWM system rather than single treatment process or specific type of waste. This review has explored distribution and evolution of LCA studies in waste management field and summarized critical parameters (system boundary, functional unit, assessment approach and data uncertainty) for conducting LCA of MSWM system. Comparison results from 45 worldwide cases indicated 33%-154% environmental benefit in Global warming potential (GWP) impact with implement of integrated solid waste management system to replace single landfill, incineration, or open dumping treatment. Key issues with upgrading of MSWM system have been highlighted to raise concern, i.e., the importance of targeted management strategy on organic and recyclable waste, the growing contribution of waste collection and transportation to the total environmental impact, as well as promoting multi-impacts assessment for MSWM system to achieve environmentally effective, economically affordable, and socially acceptable. Rather than focus on technical factors, results from this study indicated the key influences from understanding local limitation, environmental concern, management chain and comprehensive impact, providing useful strategies on improving MSWM with generalization results of LCA studies., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Emerging evidence has confirmed meteorological factors and air pollutants affect novel coronavirus disease 2019 (COVID-19). However, no studies to date have considered the impact of interactions between meteorological factors and air pollutants on COVID-19 transmission. This study explores the association between ambient air pollutants (PM 2.5 , NO 2 , SO 2 , CO, and O 3 ), meteorological factors (average temperature, diurnal temperature range, relative humidity, wind velocity, air pressure, precipitation, and hours of sunshine), and their interaction on confirmed case counts of COVID-19 in 120 Chinese cities. We modeled total confirmed cases of COVID-19 as the dependent variable with meteorological factors, air pollutants, and their interactions as the independent variables. To account for potential migration effects, we included the migration scale index (MSI) from Wuhan to each of the 120 cities included in the model, using data from 15 Jan. to 18 Mar. 2020. As an important confounding factor, MSI was considered in a negative binomial regression analysis. Positive associations were found between the number of confirmed cases of COVID-19 and CO, PM 2.5 , relative humidity, and O 3 , with and without MSI-adjustment. Negative associations were also found for SO 2 and wind velocity both with and without controlling for population migration. In addition, air pollutants and meteorological factors had interactive effects on COVID-19 after controlling for MSI. In conclusion, air pollutants, meteorological factors, and their interactions all affect COVID-19 cases.

Urban agglomerations are a primary spatial focus of socioeconomic activity and inherently include large volumes of embodied water. We have applied the concept of water metabolism health to comprehensively evaluate the overall operation of water systems in urban agglomerations and propose an innovative assessment framework. In particular, we constructed a water metabolism network (WMN) model to simulate a water system in which different cities and sectors are integrated, combining a newly compiled multiregional input-output (MRIO) table of water flow with ecological network analysis (ENA). A case study considering the Pearl River Delta (PRD) urban agglomeration in 2015 demonstrates that its network is well synergic but highly dependent, with considerable negative effects. Highly developed cities in southeastern of the PRD exhibit higher embodied water productivity and robustness but impose considerable negative effects on the water system. We found the agricultural sector to be a dominant controller of the network; the construction and service sectors represent the primary beneficiaries with strong competition. We suggest measures at various scales to improve water utilization efficiency and promote positive interactions between components, thus improving water metabolism system health for urban agglomerations.

Road traffic crashes cause fatalities and injuries of both drivers/passengers in vehicles and pedestrians outside, thus challenge public health especially in big cities in developing countries like China. Previous efforts mainly focus on a specific crash type or causation to examine the crash characteristics in China while lacking the characteristics of various crash types, factors, and the interplay between them. This study investigated the crash characteristics in Shenzhen, one of the biggest four cities in China, based on the police-reported crashes from 2014 to 2016. The descriptive characteristics were reported in detail with respect to each of the crash attributes. Based on the recorded crash locations, the land-use pattern was obtained as one of the attributes for each crash. Then, the relationship between the attributes in motor-vehicle-involved crashes was examined using the Bayesian network analysis. We revealed the distinct crash characteristics observed between the examined levels of each attribute, as well the interplay between the attributes. This study provides an insight into the crash characteristics in Shenzhen, which would help understand the driving behavior of Chinese drivers, identify the traffic safety problems, guide the research focuses on advanced driver assistance systems (ADASs) and traffic management countermeasures in China.

It is important to forecast the risk of COVID-19 symptom onset and thereby evaluate how effectively the city lockdown measure could reduce this risk. This study is a first comprehensive, high-resolution investigation of spatiotemporal heterogeneities on the effect of the Wuhan lockdown on the risk of COVID-19 symptom onset in all 347 Chinese cities. An extended Weight Kernel Density Estimation model was developed to predict the COVID-19 onset risk under two scenarios (i.e., with and without the Wuhan lockdown). The Wuhan lockdown, compared with the scenario without lockdown implementation, in general, delayed the arrival of the COVID-19 onset risk peak for 1-2 days and lowered risk peak values among all cities. The decrease of the onset risk attributed to the lockdown was more than 8% in over 40% of Chinese cities, and up to 21.3% in some cities. Lockdown was the most effective in areas with medium risk before lockdown.

Despite the extensive attention paid to emissions trading scheme (ETS) approaches, few studies have examined whether such ETS policies can lead to sustainable development in China. Drawing on the ideas of coupling and synergistic development, this study views sustainable development as the result of the interactions between the economy and the environment and constructs an index system to measure economic development and environmental quality. The system coupling model is used to reflect the synergistic interactions between the economy and the environment systems. The coordination degree model is then used to assess the economic-environmental coupling coordination degree in order to measure sustainable development. The empirical results show that the ETS can help in achieving economic-environmental sustainable development in the pilot cities. Moreover, the better the socioeconomic development of a city, the better effects of the ETS on sustainable development. However, it is more difficult to achieve economic-environmental coordinated development in industrially developed areas (e.g., Guangdong). These findings provide empirical evidence that the market-based ETS could alleviate the conflict between economic development and environmental pollution and could help in achieving sustainable development in emerging economies.

Sediment samples in this study were taken from five typical sites near the outlet of Shekou industrial district of Shenzhen City, China. The concentrations of seven elements including Cr, Cu, Cd, Pb, Hg, Zn, and As were determined respectively by atomic absorption spectrometry or atomic fluorescence spectrometry. The pollution degrees of the seven elements were assessed with the contamination factor and potential ecological risk index respectively, and their different sources were identified using multivariate statistical methods. The calculated contamination factors of these elements indicated that the sediments were at least moderately polluted by all the surveyed elements except As. The values of potential ecological risk indexes obtained decreased as the following order: Cd > Hg > Cu > As > Pb > Zn > Cr, and suggested that Cd and Hg were respectively at high and considerable environmental health risks. In addition, multivariate statistical analyses indicated that Cd, Hg, Cu, and Zn were most likely from the waste of electroplating, metal, and battery industries at Shekou industrial district, while Pb and As originated from both natural processes and anthropogenic activities along the bank of Pear River such as coal transportation and combustion, glass manufacturing, and painting, and Cr came mostly from Cr-related industries especially leather tanning within Shenzhen City. This study provided useful reference information about heavy metal contamination in the sediments in the estuarine and coastal areas with rapid urbanization and industrialization, and should be very helpful for the local governments to make relevant policies and strategies of heavy metal contamination control and management in developing countries.

Controversies on food delivery services environmental impacts have been sparked due to the growth of this economic sector. This study focuses on the environmental impacts generated by packaging waste related to urban food delivery services. In particular, the Python based web-crawling and sample survey methods are used for big data mining, and LCA-based environmental impacts evaluation and Kernel density analysis methods are combined to determine the positioning trend of food delivery service providers and expansion direction of environmental pollution load in Jing-Jin-Ji region (North China). Results indicate that (1) food delivery service packages presently account for a very small proportion (<0.1%) of municipal solid waste (MSW). However, this study also evidences that food packaging accounts for 15.7% of the total MSW generated in this region. Even if this growing market sector might have a relatively low impact, households' lifestyle might affect the results. (2) In terms of consumption quantity, plastic bags are the most used packages, accounting for 35.08%; wooden chopsticks account for 32.21% and plastic boxes account for 27.43%. Among all environmental impact categories resulting from the process of production of packages, greenhouse effect is the most distinct one. Paper boxes generate the most serious environmental pollution. (3) The distribution of environmental pollution loads resulting from food delivery service packages positively correlates with the distribution of food delivery service providers in Jing-Jin-Ji. Shijiazhuang has the highest degree of pollution resulting from food delivery service packages with the interrupt value ratio of 80%, followed by Baoding City and Chengde City, which have the interrupt value ratios of 65.1% and 48.6%, respectively. Finally, as bridges between food delivery service providers and consumers, food delivery service platforms should improve their environmental protection mechanisms. Meanwhile, the government should define a standard concerning food delivery service packages to consolidate the concept of environmental protection in the society to change the ways people consume, in order to achieve a harmonious co-existence between resource utilization and environmental protection., 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 © 2020 Elsevier Ltd. All rights reserved.)

Most previous studies on comprehensive urban carrying capacity (UCC) have estimated UCC levels and comparatively analyzed the heterogeneity of the sample cities. Very few researchers have focused on the interaction effects between different categories of UCC based on synergetic theory. To fill this gap, we constructed a panel vector autoregressive (PVAR) model to study 11 cities in the Guangdong-Hong Kong-Macao Greater Bay Area from 2000 to 2016. The ultimate goal of this study is to improve comprehensive UCC levels by forming a virtuous circle of mutual reinforcement between the four types of carrying capacity. To do so, the interaction mechanisms of the four subsystems are examined. Results show that (a) only transportation and social carrying capacity had causality between them as per the Granger causality test; (b) all four carrying capacities can support themselves (i.e., the development of economic conditions helps to improve social carrying capacity and the improvement of social carrying capacity helps to improve environmental carrying capacity); and (c) both the four carrying capacities are mostly affected by their own fluctuations. Overall transportation carrying capacity is the most important driving force among the four subsystems that interact with each other; followed by economic carrying capacity, which has promotion effect on the social and environmental aspects; social carrying capacity poses impact on the environmental dimension but not vice versa. Policy suggestions and future research directions are highlighted in the final section., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The widespread human exposure to perfluoroalkyl acids (PFAAs) has led to increasing public concern. In this study, we present a comprehensive measurement of total fluorine (TF), extractable organic fluorine (EOF), identified organic fluorine (IOF, total concentration of identified PFAAs quantified as fluorine) and 11 target PFAAs in human serum (n = 60), hair (n = 49) and nails (n = 39) collected from non-occupation exposed volunteers in 10 cities of Guangdong Province, China. The results indicated that EOF was the major form of fluorine in serum, accounting for 70-80% of TF. The levels of IOF contributed less than 10% of EOF. Perfluorooctane sulfonic acid (PFOS) was found to be the dominant PFAA with mean concentration of 23 ng·mL -1 in serum, 35 ng·g -1 in hair and 33 ng·g -1 in nail, respectively. Short-chain PFAAs (C ≤ 10) were the predominant PFAAs in three matrices. Levels of PFOS, perfluorohexane sulfonic acid (PFHxS), perfluoroundecanoic acid (PFUdA) and perfluorotridecanoic acid (PFTrDA) in males are significantly higher than those in females (p < 0.01). Significant positive correlations were observed between nail and serum for PFOS (p < 0.01), perfluorooctanoic acid (PFOA) (p < 0.05) and PFHxS (p < 0.01), suggesting that human nails, a noninvasive sample, are a promising bio-indicator for PFAA risk assessment.

Emissions of major reactive nitrogen compounds, including nitric oxide (NO), nitrogen dioxide (NO 2 ) and ammonia (NH 3 ), from heavy-duty diesel vehicles (HDDVs) place substantial pressure on air quality for many large cities in China. To control nitrogen oxide (NO X ) emissions from HDDVs, selective catalytic reduction (SCR) systems have been widely used since the China IV standards. To investigate the impacts of aftertreatment technologies and driving conditions on real-world emissions of reactive nitrogen compounds, a portable emissions measurement system was employed to test eighteen heavy-duty diesel trucks in China. The results showed that the China IV and China V HDDVs with appropriate SCR functionality could reduce NO X emissions by 36% and 53%, respectively, compared to the China III results, although their real-world emissions were still higher than the corresponding emission limits for regulatory engine tests. For these HDDVs, five samples were tested with NH 3 emissions, ranging from 1.67 ppm to 51.49 ppm. The NH 3 emission rates tended to significantly increase under high-speed driving conditions. The results indicate that the current SCR technology may have certain risks in exceeding the future China VI NH 3 limit. However, five China IV/V HDDVs were found to have SCR temperature sensors that were intentionally tampered with, resulting in comparable or even higher NO X emissions and zero NH 3 emissions. Increased NO 2 emissions due to the adoption of diesel oxidation catalysts and diesel particulate filters were also found from our experiments. This study highlights the importance of enhancing in-use compliance requirements and eliminating aftertreatment tampering for China IV and China V HDDVs., 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 © 2020 Elsevier Ltd. All rights reserved.)

An evaluation indexing system based on the theory of coordination was constructed to estimate the urban carrying capacity (UCC) of the Beijing-Tianjin-Hebei (BTH) region with four subsystems: social, economic, environmental, and transportation. This indexing system revealed the interactions between "supply" and "demand." The improved entropy method was adopted to calculate the weight of 17 indicators and evaluate the comprehensive UCC of 13 cities in the BTH region using data covering the period 1990-2018. The results showed that two cities, Tangshan (UCC of - 0.0021) and Handan (UCC of - 0.0009), were "overloaded" in 2018, while the other 11 cities were "loadable." The social and transportation subsystems played the most crucial roles in the evaluation. Based on the results, Baoding achieved the highest UCC, while that of Tangshan was the lowest. The results could play a significant role in decision-making relating to the sustainable development of the BTH region. Three policy implications are proposed based on these findings: (i) the efficiency of resource utilization and scientific allocation should be enhanced and industrial optimization and upgrading should be promoted, (ii) the coordinated development of urbanization and environment in the region should be improved, and (iii) the integration of traffic decongestion measures should be faster, and industrial docking systems should be enhanced.

The Guangdong-Hong Kong-Macao Greater Bay Area (GBA) is the most prominent urban agglomeration in China, with plans for further development. Using the regional collaboration theoretical framework for assessing urban comprehensive carrying capacity (UCC), the improved entropy method is applied to establish an index system based on a social, economic, environment, and transportation perspective to compare UCCs of the GBA's 11 cities for 2000-2016. Results show that the social subsystem is central to the evaluation system. Cities' performances vary significantly, with six becoming overloaded in 2016 and the other five remaining loadable. Guangzhou performed best, with a rising UCC; Shenzhen rebounded after a long period of decline; Hong Kong's capacity rose slightly, with some fluctuation; and Macao performed worse and continues to slide, with no signs of improvement. Overall, the UCC of the urban agglomeration showed a downward trend, with only a few cities continuing to improve. The spatial distribution for UCC was high in the north and low in the south, showing scope for improvement. The study enriches regional collaboration theory and proposes policy implications for GBA development.

There is a growing need to recycle construction and demolition waste (CDW) in order to treat the huge amount of CDW in many metropolises of China. However, the CDW recycling industry is still in its initial stage and developed unevenly across various areas of China. In spite of some qualitative discussions, the quantitative analysis of crucial policies to the development of CDW recycling industry was overlooked. Through literature review, nine influential policy instruments were identified in term of three categories, i.e. control and command policy, market-based policy and information-based policy. The stepwise regression analysis was employed to explore the relationships between the influential policies and the development level of CDW recycling industry in 52 sample Chinese cities. The results demonstrated that Green Product Label, Charge and Tax and Technical Standards had statistically significant association with the development of CDW recycling industry in sample cities. In the surveyed cities, Charge or Tax was the most common policy tool (84.6%), but Green Product Label (7.7%) and Technological standards (11.5%) were rather less frequently employed. According to the results, Green Product Label and Technical Standards should be given higher priority. In addition, landfill charge should be introduced as a fundamental impetus. These results provide directions for other cities to facilitate the development of their CDW recycling industry., 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 © 2020 Elsevier Ltd. All rights reserved.)

Background: Ambient PM 2.5 has been identified as the top leading cause of risk-attributable deaths worldwide, particularly in China. Evidence suggested that PM 1 contributed the most majority of PM 2.5 concentrations in Chinese cities. However, epidemiologic knowledge to date is of wide lack regarding PM 1 -associated health effects., Methods: We collected daily records of all-cause emergency department visits (EDVs) and ground measurements of ambient air pollutants and meteorological factors in Guangzhou and Shenzhen, China, 2015-2016. Case-crossover design and conditional logistic regression models were used to comparatively assess the short-term effects of ambient PM 1 , PM 2.5 , and PM 10 on EDVs. Stratified analyses by gender, age and season were performed to identify vulnerable groups and periods., Results: PM 1 , PM 2.5 and PM 10 were all significantly associated with increased EDVs in both cities. Population risks for EDVs increased by 2.2% [95% confidence interval, 1.8 to 2.6] in Guangzhou and 1.7% [1.0 to 2.4] in Shenzhen, for a 10 μg/m 3 rise in PM 1 at lag 0-1 days and lag 0-4 days, respectively. Relatively lower risks were found to be associated with PM 2.5 and PM 10 . PM-EDVs associations exhibited no gender differences, but varied across age groups. Compared with adults and the elderly, children under 14 years-of-age suffered higher PM-induced risks. Results from both cities suggested greatly significant effect modification by season, with consistently stronger PM-EDVs associations during cold months., Conclusions: Our study added comparative evidence for increased EDVs risks associated with short-term exposures to ambient PM 1 , PM 2.5 and PM 10 . Besides, PM-associated effects were significantly stronger among children and during cold months., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Purpose: The purpose of this study was to investigate the influence of natural environmental factors on the spatial distribution of marathon events in China, and to identify the suitable natural environmental factors for the marathon events., Methods: Geographic information system (GIS) spatial analysis tools were used to perform coupling analysis, e.g. overlap, neighborhood, intersection and buffer for terrain, climate, air quality, mountains and water resources with 342 marathon events held in China in 2018., Results: The results indicate that the spatial distribution of marathon events in China is negatively correlated with the elevation of the terrain (plain > hill > plateau > mountain > basin); climate (subtropical monsoon climate > temperate monsoon climate > temperate continental climate > tropical monsoon climate > plateau alpine climate), air quality (level 3 > level 2 > level 4 > level 1). Results indicate that buffer zones can protect water resources: there are 24 items in the buffer zone of river 0.5 km and lake 1 km, 131 items in the buffer zone of river 3 km and lake 5 km, 191 items in the buffer zone of river 5 km and lake 10 km, 298 items in the buffer zone of river 10 km and lake 20 km. Results indicate for mountain range buffer: 13 items in the 20 km buffer and 39 items in the 50 km buffer., Conclusions: Marathon events are more likely to be held on the third rung of China's topography where a city has a typical landform (plains, basins, hills, or mountain) with good climate and air quality. Meanwhile a city with water and mountain resources for recreational events such as cross-country or obstacle course are essential. The contribution of this study is to systematically and intuitively reflect the influence of natural environment factors on the distribution of marathon events in China, and to provide evidence for the medium and long-term planning of marathon events in China, the selection of venues for different types of marathon events and how to attract participants., Competing Interests: The authors declare no conflict of interest.

Monitoring the use of alcohol and tobacco in the population is important for public health planning and evaluating the efficacy of intervention strategies. The aim of this study was to use wastewater-based epidemiology (WBE) to estimate alcohol and tobacco consumption in a number of major cities across China and compare WBE estimates with other data sources. Daily composite influent wastewater samples were collected from wastewater treatment plants (WWTPs) across China in 2014 (n = 53) and 2016 (n = 45). The population-normalized daily consumption estimated by WBE were compared with other data sources where available. The average consumption of alcohol was 8.1 ± 7.0 mL ethanol/person aged 15+/day (EPD) in the investigated cities of 2016 while those involved in 2014 had an average consumption of 4.7 ± 3.0 EPD. The average tobacco consumption was estimated to be 3.7 ± 2.2 cigarettes/person aged 15+/day (CPD) in 2016 and 3.1 ± 1.9 CPD in 2014. The changes in the average consumption in those cities from 2014 to 2016 were supported by the results from a limited number of WWTPs where samples were collected in both years. Consumption of alcohol and tobacco in urban China is at a medium level compared with other countries on a per capita basis. WBE estimates of tobacco consumption were relatively comparable with results of traditional surveys and sales statistics. WBE estimates of alcohol consumption were lower than WHO survey results, probably due to EtS degradation and uncertainty in the EtS excretion factor., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

With the unprecedented urbanization during the past three decades, air quality in many Chinese cities has been a serious issue which poses great challenges for urban sustainability. This study examines the health consequences of development patterns in China by establishing the linkage between urban form, air pollution level, and cardiorespiratory mortality rate. We assembled a dataset by compiling a series of variables from multiple sources, including China's Disease Surveillance Points (DSP) system, which forms a nationally representative sample of mortality for the year 2005, Chinese census, satellite imagery, and the Chinese National Land Use Database. After controlling for local climate, demography, socioeconomics, and other pollution factors, this study finds that urban form elements (e.g., urban density, fragmentation level, forest/green space ratio) have significant influences on PM 2.5 (atmospheric particulate matter with a diameter of less than 2.5 micrometers) concentration, thus influencing the incidence of cardiorespiratory mortality at the county level. These results may help explain how the type and pattern of development shape public health by influencing air quality and form an evidence-based land use policy to improve environmental quality and public health.

Objectives: Plenty of studies have shown that wind velocity has an influence on airborne diseases. There is, however, no consistent conclusion found on the relationship between wind velocity and mumps, and the regional heterogeneity has been largely neglected in previous studies. This study aims to explore the association between wind velocity and mumps in Shenzhen., Study Design: Ecological study., Methods: Sixteen subdistricts with the highest incidence rates of mumps were selected from Shenzhen city, and the multilevel distributed lag-nonlinear model was conducted to explore the relationship between mumps cases and wind velocity via the dlnm and lme4 packages of the software R 3.4.3., Results: In Shenzhen, a total of 16,997 mumps cases were reported between 2013 and 2016, and the means of daily rainfall, temperature, relative humidity, and 10 min wind velocity were 5.74 mm, 23.27 °C, 76.31% and 1.87 m/s, respectively. Obvious nonlinear correlation relationships of wind velocity and mumps risk were found, where a reverse-V curved shape was shown in the exposure dimension with the logRR value of mumps peaking at 2 m/s, and the type of nonlinear correlation varying with the levels of wind velocity in lag dimension with a peak at two lag weeks., Conclusions: The lag and nonlinear association between wind velocity and number of mumps cases were examined, while there was no statistically significant associations for other meteorological factors accounting for the regional heterogeneity. Results from this study indicated that public health administrators could strengthen health education in schools on ventilation management to prevent and control mumps outbreaks., (Copyright © 2019 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.)

This study investigated the levels, spatial distribution, sources, and ecological risks of 16 perfluorinated compounds (PFCs) in 68 surface soil samples (0-20 cm) from 7 cities in the Pearl River Delta (PRD), China. Sixteen target PFCs, including perfluoroalkyl carboxylic acids (PFCAs, C 5 -C 14 , C 16 , and C 18 ) and perfluoroalkyl sulfonic acids (PFSAs, C 4 , C 6 , C 8 , and C 10 ), were analyzed by high-performance liquid chromatography-negative electrospray ionization-tandem mass spectrometry (HPLC/ESI-MS/MS). Concentrations of total PFCs (∑PFCs) ranged from 2.19 to 98.5 μg kg -1 (dry weight, dw), with an average of 5.97 μg kg -1  dw. Perfluorooctane sulfonate (PFOS) was the dominant PFC, accounting for 23.9% of ∑PFCs. The highest ∑PFCs was found in the soil sample collected from Dongguan with a large number of manufacturing industries. There were no significant differences of ∑PFCs among unban, industrial, and agricultural soils, indicating similar pollution sources in soil of the PRD. More than 70% of ∑PFCs in soil of the PRD could be attributed to the four principal components, represented by PFOS and perfluorooctanoic acid (PFOA), perfluoropentanoic acid (PFPeA) and perfluorohexanoic acid (PFHxA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUdA). Ecological risk assessment indicated that PFOA had low risk to soil plants and animals. However, the risk of PFOS to soil plants was relatively high in some studied regions.

The purpose of this study is to explore the spatial distribution pattern and influencing factors of the Chinese marathon. Geographic Information System (GIS) related spatial analysis tools were used to calculate the following-averaged nearest neighbor index, nuclear density analysis and hot spot analysis among others. The spatial distribution evolution characteristics and the influencing factors of eighteen Chinese marathon events in 2010, 129 in 2015 and 342 in 2018 were analyzed. The results show that (a) in 2010 the nearest neighbor ratio was 1.164714, Moran's I was -0.010165 (type: Random), in 2015 it was 0.502146, Moran's I was 0.066267 (type: Clustered) and in 2018 it was 0.531149 and Moran's I was 0.083485 (type: Clustered); (b) in 2010 there was a 333.6 km search radius; the core circle of the Yangtze River Delta was adopted. In 2015 and 2018, a search radius of 556 km was adopted, which was respectively obtained from the core circle of the Yangtze River Delta, the core circle of Beijing-Tianjin-Hebei and the core circle of East China; (c) according to the Z -value data, East China and North China in 2015 passed 95% confidence in five provinces and municipal hot spots, passed 90% confidence in three hot spots and passed 95% confidence in Chongqing Cold Point. In 2018, East China, North China, Central Region and eight other provinces and cities' hot spots passed 95% confidence, four hot spots passed 90% confidence, the Tibet Autonomous Region cold spot passed 90% confidence. Conclusion: The overall distribution of marathon events is greater in the eastern region than the western region, greater in the southern region than the northern region and greater in coastal regions than the inland regions; the nuclear density distribution has spread from the Yangtze River Delta mononuclear circle in 2010 to the core circle of the entire East China region. Moreover, it spread to North China, Central China and South China; the distribution of hot spots spread from Shanghai, Jiangsu and Zhejiang to the entire North China and East China regions. During the past thirty-eight years of development of the Chinese marathon, it has been divided into three stages due to different political, economic and social environments.

Background: Temperature variability (TV) is closely associated with climate change, but there is no unified TV definition worldwide. Two novel composite TV indexes were developed recently by calculating the standard deviations of several days' daily maximum and minimum temperatures (TV daily ), or hourly mean temperatures (TV hourly )., Objectives: This study aimed to compare the mortality risks and burden associated with TV daily and TV hourly using large time-series datasets collected from multiple locations in China, United Kingdom and United States., Methods: We collected daily mortality and hourly temperature data through 1987 to 2012 from 63 locations in China (8 communities, 2006-2012), United Kingdom (10 regions, 1990-2012), and USA (45 cities, 1987-2000). TV-mortality associations were investigated using a three-stage analytic approach separately for China, UK, and USA. First, we applied a time-series regression for each location to derive location-specific TV-mortality curves. A second-stage meta-analysis was then performed to pool these estimated associations for each country. Finally, we calculated mortality fraction attributable to TV based on above-described location-specific and pooled estimates., Results: Our dataset totally consisted of 23, 089, 328 all-cause death cases, including 93, 750 from China, 7,573,716 from UK and 15, 421, 862 from USA, respectively. In despite of a relatively wide uncertainty in China, approximately linear relationships were consistently identified for TV daily and TV hourly . In the three countries, generally similar lag patterns of TV effects were consistently observed for TV daily and TV hourly . A 1 °C rise in TV daily and TV hourly at lag 0-7 days was associated with mortality increases of 0.93% (95% confidence interval [CI]: 0.12, 1.74) and 0.97% (0.18, 1.77) in China, 0.33% (0.15, 0.51) and 0.41% (0.21, 0.60) in UK, and 0.55% (0.41, 0.70) and 0.51% (0.35, 0.66) in USA, respectively. Larger attributable fractions were estimated using TV daily than those using TV hourly , with estimates at 0-10 days of 3.69% (0.51, 6.75) vs. 2.59% (0.10, 5.01) in China, 1.14% (0.54, 1.74) vs. 0.98% (0.55, 1.42) in UK, and 2.57% (1.97, 3.16) vs. 1.67% (1.15, 2.18) in USA, respectively. Our meta-regression analyses indicated higher vulnerability to TV-induced mortality risks in warmer locations., Conclusions: Our study added multi-country evidence for increased mortality risk associated with short-term exposure to large temperature variability. Daily and hourly TV exposure metrics produced generally comparable risk effects, but the attributable mortality burden tended to be higher using TV daily instead of TV hourly ., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The high pollutant loads discharged from cities pose risks to urban waterways, and in turn the estuarine environments, making it challenging to improve urban liveability. Past studies on the behaviour of pollutants in rivers have largely investigated their transport along the waterway, primarily focusing on the movement of water and sediment. However, the current approaches in pollutant transport modelling provide limited insights into how pollutant transfer between water and sediment phases influences their transport from the upstream towards the estuarine environment. This research study firstly identified typical patterns of metal loads along an urban river in a highly populated city in China. The outcomes were then used to conceptualise metal transfer between water and sediment phases. It was noted that physico-chemical characteristics of water and sediments play a key role in metal transfer between the two phases, and the dominant transfer path (sediment to water/water to sediment) is different between different metals, independent of their origin (crustal, anthropogenic or marine-related). Several scenarios were derived from the conceptualisation of metal behaviour. These in turn were then used to develop real-world scenarios of metal transport in rivers based on the field data. The conceptualisation of metal behaviour confirmed that each metal is likely to have a dominant phase of transport (sediment/water), which is influenced by the dominant transfer path of that metal between water and sediments., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Numerous studies have examined the correlation between economic growth and air pollution, but few focuses on the nexus between environmental regulation and <2.5 μm (PM 2.5 ) fine particle matter. Using Spatial Durbin Model (SDM) and Spatial Two-stage Least Squares (2SLS) methods to analyze 277 Chinese cities over the period 2002-2010, this paper finds inverted U-shaped relationships between PM 2.5 concentration and formal/informal environmental regulations for the whole and eastern and western regions. By removing the depression year of 2008, regulation effect on pollution strengthened, indicating that the main task for local governments in crisis is to avoid GDP decline rather than official promotion. Further, green technological innovation and industrial structure optimization induced by environmental regulation is shown to be beneficial for haze pollution mitigation. Some policy recommendations are proposed in conclusion., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

As China and other developing countries continue to urbanize over the next decades, construction and demolition waste (CDW) management has been becoming a significant challenge for urban sustainability in terms of the environment, economy, and safety. However, accurate estimations or statistics of CDW generation are absent from the official national report in spite of their importance to devise sensible interventions to tackle CDW-related problems. This paper examines and compares the applications of three prevailing methods for estimating CDW, including the weight-per-construction-area method (WAM), buildings' life span-based method, and weight-per-capita method. Specifically, China has been chosen as the case study. This study implies that the weight-per-construction-area method is more appropriate because of the data availability and accuracy at a city or national level. The results of WAM indicate that a total of 4.1 billion metric tons (Bt) of CDW were generated in China in 2016, mainly from demolition waste (85%). Taking the changes of buildings' life span into account, a projection analysis reveals that the cumulative CDW generation will be 50 Bt between 2017 and 2040 in China (equal to approximately 38 years cumulative generation of global municipal solid waste). Overall, the findings provide some methodological options for scholars, practitioners, and decision-makers to more accurately estimate the amount of the CDW and to develop a more environmentally sound management strategy.

Concentrations, sources and risk of 16 priority polycyclic aromatic hydrocarbons (PAHs) were investigated in surface sediments from 19 representative tributaries in a regional scale of Chongqing City. The total concentration of 16 PAHs (ΣPAHs) ranged from 221 to 3205 ng g -1 with a mean of 1055 ng g -1 . Most tributaries of the Jialing River exhibited significantly higher ΣPAHs concentrations (mean 1864 ng g -1 ) compared to those flowing into the Yangtze River (mean 787 ng g -1 ). Isomeric ratio and hierarchical clustering analysis showed combustion may impact sedimentary PAHs at most center sites of the City, while PAHs at most sites were mixed of petrogenic and pyrogenic sources. Toxicity equivalency concentration for carcinogenic PAH were 2-4 times more than the Dutch limit. More comprehensive assessment of safety is suggested to reduce environmental risk of PAHs in sediments.

The paper reviews the existing applications of sensing technologies for measuring construction off-road vehicle emissions (COVE) such as earthmoving equipment. The current literature presented different measurement methods and reported the results of utilisation of new technologies for measuring COVE. However, previous papers used different technology applications covering only a part of the monitoring process with its own limitations. Since technologies are advancing and offering novel solutions, there is an urgent need to identify the gaps, re-evaluate the current methods, and develop a critical agenda for automating the entire process of collecting emissions data from construction sites, and monitoring the emission contributors across cities. This paper systematically identifies relevant papers through a search of three key databases-Web of Science, Engineering Valley and Scopus-covering the publications in the last decade from 2008 to 2017. An innovative robust research method was designed to select and analyse the relevant papers. The identified papers were stored in a data set, and a thematic algorithm employed to find the clusters of papers which might be potentially relevant. The selected papers were used for further micro-thematic analysis to find key relevant papers on COVE, and the gap in the literature. A sample of relevant papers was found relevant to COVE and critically reviewed by coding and content analysis. This paper critically reviews the selected papers and also shows that there is a considerable gap in the applications of new technologies for measuring in-use COVE in real time based on real activities toward automated methods. This review enables practitioners and scholars to gain a concrete understanding of the gap in measuring COVE and to provide a significant agenda for future technology applications.

The rapid urbanization in China since the 1970s has led to an exponential growth of metal stocks (MS) in use in cities. A retrospect on the quantity, quality, and patterns of these MS is a prerequisite for projecting future metal demand, identifying urban mining potentials of metals, and informing sustainable urbanization strategies. Here, we deployed a bottom-up stock accounting method to estimate stocks of iron, copper, and aluminum embodied in 51 categories of products and infrastructure across 10 Chinese megacities from 1980 to 2016. We found that the MS in Chinese megacities had reached a level of 2.6-6.3 t/cap (on average 3.7 t/cap for iron, 58 kg/cap for copper, and 151 kg/cap for aluminum) in 2016, which still remained behind the level of western cities or potential saturation level on the country level (e.g., approximately 13 t/cap for iron). Economic development was identified as the most powerful driver for MS growth based on an IPAT decomposition analysis, indicating further increase in MS as China's urbanization and economic growth continues in the next decades. The latecomer cities should therefore explore a wide range of strategies, from urban planning to economy structure to regulations, for a transition toward more "metal-efficient" urbanization pathways.

How can growing cities be expanded in a sustainable way? Huge waste generation has become a major challenge in many growing cities, particularly in developing countries. China's annual C&D waste generation was and estimated 2.4 billion tonnes in the past decade, which is 15 times more than municipal solid waste generation. India has less C&D waste generation than China, yet still is as high as 530 million tons in 2013. However, only around 5% of C&D waste was reused in these countries and the rest largely ends up in dumping sites for disposal. As China and other developing countries continue to urbanize in the next decades, C&D waste management will continue to be a significant challenge for urban sustainability in terms of the environment, economics, and safety. We therefore critically reviewed the C&D waste generation, management, and challenges faced by the fast expanding cities in China and other developing countries. We also compared the current characteristics of key C&D waste systems in developing and developed countries. Recommendations for swift action are made for policy makers in growing cities., (Copyright © 2018 Elsevier Ltd. All rights reserved.)