Provincial Capital Cities In China Research Articles

How urbanization shapes the ecosystem carbon sink of vegetation in China: A spatiotemporal analysis of direct and indirect effects

Rapid urbanization has led to extensive effects on the spatio-temporal patterns of the carbon sources and sinks in ecosystems. However, due to the lack of long-term continuous land use/cover change (LUCC) data, there has been limited discussion on the spatio-temporal impacts of urbanization on carbon sources/sinks and the non-linear characteristics of urban changes over time. This study focused on the impact of urbanization on vegetation net ecosystem productivity (NEP) in 31 provincial capital cities in China from 1990 to 2019, using land use change data and NEP indicators, to analyze the change patterns and response modes of urbanization intensity and NEP. The study found that: (1) During the period of 1990–1995, almost all cities in China experienced a turning point of urbanization rate from decreasing to increasing, while after 2000, the urbanization rate declined significantly; (2) Climate background affects the negative impact of urbanization on NEP, especially in warm and humid climate background, while the direct impact of urbanization on vegetation is more significant; (3) Overall, urbanization in China aggravated the negative impact of urbanization on NEP from 1990 to 2019, especially in cold and arid climate background, which would further exacerbate the negative impact of urbanization. This study helps us better understand the impact of Chinese urbanization on ecosystem carbon sinks and mitigating the carbon emissions pressure of urban environments.

A Spatiotemporal Hierarchical Analysis Method for Urban Traffic Congestion Optimization Based on Calculation of Road Carrying Capacity in Spatial Grids

Traffic congestion is a globally widespread problem that causes significant economic losses, delays, and environmental impacts. Monitoring traffic conditions and analyzing congestion factors are the first, challenging steps in optimizing traffic congestion, one of the main causes of which is regional spatiotemporal imbalance. In this article, we propose an improved spatiotemporal hierarchical analysis method whose steps include calculating road carrying capacity based on geospatial data, extracting vehicle information from remote sensing images to reflect instantaneous traffic demand, and analyzing the spatiotemporal matching degree between roads and vehicles in theory and in practice. First, we defined and calculated the ratio of carrying capacity in a regional road network using a nine-cell-grid model composed of nested grids of different sizes. By the conservation law of flow, we determined unbalanced areas in the road network configuration using the ratio of the carrying capacity of the central cell to that of the nine grid cells. Then, we designed a spatiotemporal analysis method for traffic congestion using real-time traffic data as the dependent variables and five selected spatial indicators relative to the spatial grids as the independent variables. The proposed spatiotemporal analysis method was applied to Chengdu, a typical provincial capital city in China. The relationships among regional traffic, impact factors, and spatial heterogeneity were analyzed. The proposed method effectively integrates GIS, remote sensing, and deep learning technologies. It was further demonstrated that our method is reliable and effective and enhances the coordination of congested areas by virtue of a fast calculation speed and an efficient local balance adjustment.

The improved analytical stochastic model of infiltration trenches for stormwater quantity control

As one of the infiltration-based low-impact development (LID) measures, infiltration trenches are widely used to reduce runoff and improve water quality. The conventional analytical stochastic approach developed for use in the hydrologic design of infiltration trenches often overestimates the trench's runoff reduction performance when the infiltration rate at the bottom of the trench exceeds some high level or when the size of the trench is smaller than some threshold level. Furthermore, the appropriateness of using kernel density estimation (KDE) for rainfall event separation and frequency analysis has not been examined yet in the actual hydrologic design of LIDs. To overcome these deficiencies, an improved analytical stochastic model (ASM) was developed in this study incorporating the KDE-based rainfall event characterization and a modified formula for estimating the effective storage capacity of trenches. The calibration, verification and application of the improved ASM were systematically presented and their results were discussed. The accuracy of the improved ASM were verified by comparing the analytical results against the corresponding continuous simulation results. A large number of design cases in nine provincial capital cities of China were analyzed using the improved ASM and considering the effects of soil types, trench's storage reservoir depth, area ratio, and climate conditions. The improved ASM of infiltration trenches is useful for quickly and accurately assessing their water quantity control performances. The results indicated that the accuracy of improved ASM improved by up to 71 % in terms of R-square among the 9 study areas compared to conventional ASM. The improved ASM can be used to directly and quickly calculate the useful hydrologic performance indices for a given trench size, soil condition, area ratio and local climate condition, it can thus provide scientific guidance for the Sponge City construction in China and sustainable urban stormwater management.

The impact of fireworks burning on air quality and their health effects in China during Spring Festivals of 2015–2022

Ambient monitoring online data of six criteria air pollutants (PM2.5, PM10, SO2, NO2, O3 and CO) in 31 provincial capital cities in China during Spring Festivals from 2015 to 2022 were analyzed to estimate contributions of fireworks burning to PM2.5 and their health effects. It shows that daily average concentrations of PM2.5, PM10, SO2, NO2, and CO during Spring Festivals of 2015-2022 dropped remarkably by 36.5%, 48.9%, 70.6%, 29.7%, and 36.8%, respectively, while 8h O3 concentrations increased significantly by 21.6%. Average contributions of fireworks burning to PM2.5 during intensive fireworks burning periods from 2015 to 2022 were 44.8 ± 14.7 %, 56.2 ± 16.9 %, 50.1 ± 16.2 %, 46.0 ± 16.8 %, 44.3 ± 14.9 %, 33.2 ± 20.7 %, 44.5 ± 15.5 % and 35.2 ± 23.3 %, respectively. The total excess health risk (ERtotal) based on Chinese Ambient Air Quality Standards (CAAQS) and World Health Organization (WHO) air quality guidelines, and health-risk based air quality index values (HAQI) were estimated. Annual average values of ERtotal based on the WHO standard were 1.5–4.7 times as many as those estimated by CAAQS standards and annual average values of HAQI based on CAAQS Grade Ⅰ standard were higher than those based on CAAQS Grade Ⅱ standard. Main health risk factors were different under different air quality standards. It is necessary to further improve air quality to protect human health during Spring Festivals in China in the future.

Health Care–Seeking Behaviors, Disease Progression, Medications, Knowledge of, and Attitudes Toward Systemic Lupus Erythematosus in China: Cross-sectional Survey Study

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease involving multiple organs throughout the body. The health care-seeking behaviors, disease progression of SLE, and patients' knowledge of and attitudes toward SLE have not been characterized in China. The aim of this study was to depict the health care-seeking behaviors, disease progression, and medications in patients with SLE and to examine the factors associated with their disease flares, knowledge, and attitudes toward SLE in China. We conducted a cross-sectional survey in 27 provinces in China. Descriptive statistical methods were used to depict the demographic characteristics, health care-seeking behaviors, medications, and health status. Multivariable logistic regression models were used to identify the factors associated with disease flares, medication changes, and attitudes toward SLE. An ordinal regression model was used to examine the factors associated with the knowledge of the treatment guidelines. We recruited 1509 patients with SLE, and 715 had lupus nephritis (LN). Approximately 39.96% (603/1509) of the patients with SLE were primarily diagnosed with LN, and 12.4% (112/906) developed LN (mean time 5.2 years) from non-LN. Patients whose registered permanent residences or workplaces in other cities from the same province and adjacent provinces seeking health care accounted for 66.9% (569/850) and 48.8% (479/981) of the patients with SLE in the provincial capital cities, respectively. Mycophenolate mofetil was the most commonly used immunosuppressive drug in patients without LN (185/794, 23.3%) and patients with LN (307/715, 42.9%). Femoral head necrosis (71/228, 31.1%) and hypertension (99/229, 43.2%) were the most common adverse event (AE) and chronic disease during treatment, respectively. Change of hospitals for medical consultation (odds ratio [OR] 1.90, 95% CI 1.24-2.90) and development of 1 chronic disease (OR 3.60, 95% CI 2.04-6.24) and AE (OR 2.06, 95% CI 1.46-2.92) and more were associated with disease flares. A pregnancy plan (OR 1.58, 95% CI 1.18-2.13) was associated with changes in medication. Only 242 (16.03%) patients with SLE were familiar with the treatment guidelines, and patients with LN tended to be more familiar with the disease (OR 2.20, 95% CI 1.81-2.68). After receiving treatment, 891 (59.04%) patients changed their attitudes toward SLE from fear to acceptance, and patients with college education or higher (OR 2.09, 95% CI 1.10-4.04) were associated with a positive attitude toward SLE. A large proportion of patients seeking health care in the provincial capital cities of China migrated from other cities. Persistent monitoring of potential AEs and chronic diseases during SLE treatment and managing patients who changed hospitals for medical consultation are essential for controlling disease flares. Patients had insufficient knowledge about SLE treatment guidelines and would benefit from health education to maintain a positive attitude toward SLE.

Feasibility of condensate water recycle of split air handling unit in Chinese University buildings

Recycling the condensate water of the air conditioner could be explored as an alternative water source to contribute to building the green campus. This paper explored the condensate water production through actual measurement based on a split air handling unit (SAHU) in a university building. Then, the statistical analysis was used to analyze the recycling feasibility and the impact factors of the condensate water production in 31 Chinese provincial capital cities to obtain the recycling potential map of the condensate water generated from a SAHU. Results showed that: (1) In the measurement, the amount of condensate water produced by a single split air conditioner was 1.6 kg from 12:40 to 13:40. Therefore, the daily output of condensate water of the air conditioner with the university operation schedule could reach 52.99 kg during the main air-conditioning season. (2) Among the 31 provincial capital cities in China, the largest condensate water outputs could be found in the Hot Summer and Warm Winter zone and the Hot Summer and Cold Winter zone, with an average monthly output of 1600 kg and 1100 kg, respectively. (3) Regression analysis showed that the dry-bulb temperature and dew point temperature of outdoor air had the highest positive and significant influence on condensate water production. The objective of this study is to provide theoretical guidance for the design and energy conservation evaluation of the feasibility of SAHU condensate water recycling in universities.

Exposure and Inequality of PM2.5 Pollution to Chinese Population: A Case Study of 31 Provincial Capital Cities from 2000 to 2016.

Fine particulate matter (PM2.5) exposure has been linked to numerous adverse health effects, with some disadvantaged subgroups bearing a disproportionate exposure burden. Few studies have been conducted to estimate the exposure and inequality of different subgroups due to a lack of adequate characterization of disparities in exposure to air pollutants in urban areas, and a mechanistic understanding of the causes of these exposure inequalities. Based on a long-term series of PM2.5 concentrations, this study analyzed the spatial and temporal characteristics of PM2.5 in 31 provincial capital cities of China from 2000 to 2016 using the coefficient of variation and trend analyses. A health risk assessment of human exposure to PM2.5 from 2000 to 2016 was then undertaken. A cumulative population-weighted average concentration method was applied to investigate exposures and inequality for education level, job category, age, gender and income population subgroups. The relationships between socioeconomic factors and PM2.5 exposure concentrations were quantified using the geographically and temporally weighted regression model (GTWR). Results indicate that the PM2.5 concentrations in most of the capital cities in the study experienced an increasing trend at a rate of 0.98 μg m−3 per year from 2000 to 2016. The proportion of the population exposed to high PM2.5 (above 35 μg m−3) increased annually, mainly due to the increase of population migrating into north, east, south and central China. The higher educated, older, higher income and urban secondary industry share (SIS) subgroups suffered from the most significant environmental inequality, respectively. The per capita GDP, population size, and the share of the secondary industry played an essential role in unequal exposure to PM2.5.

The Spatial Interaction Effect of Green Spaces on Urban Economic Growth: Empirical Evidence from China.

This paper measures the impact of urban green space construction rate on urban economic growth from the perspective of spatial interaction. To this end, we collect panel data of 31 provincial capital cities in China from 2001 to 2020 and use spatial economics models for empirical testing. The research results are summarized as follows: the level of green space construction can attract talents and investment by improving the environmental level of the city, and these financial expenditures, foreign investment, and talents are conducive to urbanization, thus having a significant positive impact on urban economic development. In addition, it also has a significant positive spatial spillover effect. In addition, the construction of urban green space will also stimulate the environmental protection of neighboring cities, which has a significant positive spatial dependence. At this time, talents and investment are affected by the environmental construction of neighboring cities, and the economic development of the city has also been significantly improved. The spatial spillover effect of green space construction on the economic level of surrounding cities is also positive. The empirical conclusions provide references for implementing green development strategies and promoting high-quality economic development.

Patch-Based Local Climate Zones Mapping and Population Distribution Pattern in Provincial Capital Cities of China

Accurate urban morphology provided by Local Climate Zones (LCZ), a universal surface classification scheme, offers opportunities for studies of urban heat risk, urban ventilation, and transport planning. In recent years, researchers have attempted to generate LCZ maps worldwide with the World Urban Database and Access Portal Tools (WUDAPT). However, the accuracy of LCZ mapping is not satisfactory and cannot fulfill the quality demands of practical usage. Here, we constructed a high-quality sample dataset from Chinese cities and presented a patch-based classification framework that employs chessboard segmentation and multi-seasonal images for LCZ mapping. Compared with the latest WUDAPT method, the overall accuracy for all LCZ types (OA) and urban LCZ types (OAu) of our framework increased by about 10% and 9%, respectively. Furthermore, based on the analysis of population distribution, we first gave the population density of different built-up LCZs of Chinese cities and found a hierarchical effect of population density among built-up LCZs in different size cities. In summary, this study could serve as a valuable reference for producing high-quality LCZ maps and understanding population distribution patterns in built-up LCZ types.

National-scale urinary phthalate metabolites in the general urban residents involving 26 provincial capital cities in China and the influencing factors as well as non-carcinogenic risks

Phthalates (PAEs) are widely used in daily products but can cause a variety of adverse effects in humans. Few studies have been carried out on human internal exposure levels of PAEs on a large-scale, especially in developing countries. In the present study, 1161 urine samples collected from residents of 26 provincial capitals in China were analyzed for nine phthalate metabolites (mPAEs). The chemicals were widely detected, and the median specific gravity adjusted urinary concentration of Σ9mPAEs was 278 μg/L. Di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DnBP) were the main parent PAEs that the residents were exposed to. Demographic characteristics, such as age and educational level, were significantly associated with PAE exposure. Children and the elderly had higher mPAE levels. Subjects with lower educational levels were more frequently exposed to DnBP and DEHP. However, mono-ethyl phthalate showed the opposite trend, i.e., higher concentrations in subjects aged 18–59 years and with higher educational levels. Geographic differences were detected at the national scale. Residents in northeastern and western China had higher levels of mPAEs than those in central China, most likely because of different industrial usage of the chemicals and different living habits and living conditions of the residents. Health risk assessment showed that hazard indices of PAEs ranged from 0.07 to 9.34, with 20.0% of the subjects being concern for potential non-carcinogenic risk as assessed by Monte Carlo simulation. DEHP and DnBP were the primary contributors, representing 96.7% of total risk. This first large-scale study on PAE human internal exposure in China provides useful information on residents' health in a developing country, which could be used for chemical management and health protection.

Human health risk assessment of heavy metals from PM2.5 in China's 29 provincial capital cities.

After years of governance, China's PM2.5 pollution has improved significantly, but some problems remain. PM2.5 is the carrier of many heavy metals, and it has a stronger capacity to carry heavy metals, causing more significant harm to public health. At present, most of the studies on PM2.5-bound heavy metals in China are based on individual cities, and there are few studies from China's provincial capital cities. Given the above reasons, this paper described the pollution characteristics of PM2.5-bound heavy metal (Hg, Pb, Cd, As, Cr(VI), Ni) in 29 provincial capital cities in China (except Hohhot and Lhasa). Furthermore, the human health risk assessment recommended by US EPA was used to evaluate the carcinogenic and non-carcinogenic risks of the male adults, the female adults, and the children. The results indicated that (1) the children were facing a higher risk value of PM2.5-bound heavy metals than the adults; (2) Cr, As, and Pb were the top three elements that contributed to the average non-carcinogenic risk, while Cr(VI), As, and Cd were the three elements with the highest carcinogenic risk; and (3) the concentrations of PM2.5-bound heavy metals in the provincial capital cities of northern China were worse than those in the South. In response to the above conclusions, this paper put forward: (1) the government should strengthen the management of metallurgical industry and coal-burning industrial enterprises; (2) establish a real-time monitoring system for toxic and harmful heavy metal pollutants carried in the atmosphere as soon as possible; (3) concern on the regional synergies to form pollution control metropolitan areas.

Contribution of Urban Destinations to Physical Activity

Past studies have investigated the association between the built environment and active lifestyle, but the environmental exposure in most of these studies was measured in residential settings with predefined boundaries. In this study, we investigated the relationship between destinations in cities and walking behaviors in national and provincial capital cities in China based on a nationwide smartphone dataset. We identified destinations that were strongly and consistently associated with walking behaviors based on geographic information systems (GIS) spatial analysis. Results from this study suggest that certain components, especially parks, rivers, running tracks, of the built environment were positively associated with walking behaviors. Parks were consistently associated with more frequent walking behaviors while rivers were associated with longer walking trajectories. Findings from this study help better understand to what extent urban destinations influence physical activities and support evidence-based urban planning and health promotion in cities.

Comparisons of Combined Oxidant Capacity and Redox-Weighted Oxidant Capacity in Their Association with Increasing Levels of COVID-19 Infection

Background: Ozone (O3) and nitrogen dioxide (NO2) are substances with oxidizing ability in the atmosphere. Only considering the impact of a single substance is not comprehensive. However, people’s understanding of “total oxidation capacity” (Ox) and “weighted average oxidation” (Oxwt) is limited. Objectives: This investigation aims to assess the impact of Ox and Oxwt on the novel coronavirus disease (COVID-19). We also compared the relationship between the different calculation methods of Ox and Oxwt and the COVID-19 infection rate. Method: We recorded confirmed COVID-19 cases and daily pollutant concentrations (O3 and NO2) in 34 provincial capital cities in China. The generalized additive model (GAM) was used to analyze the nonlinear relationship between confirmed COVID-19 cases and Ox and Oxwt. Result: Our results indicated that the correlation between Ox and COVID-19 was more sensitive than Oxwt. The hysteresis effect of Ox and Oxwt decreased with time. The most obvious statistical data was observed in Central China and South China. A 10 µg m−3 increase in mean Ox concentrations were related to a 23.1% (95%CI: 11.4%, 36.2%) increase, and a 10 µg m−3 increase in average Oxwt concentration was related to 10.7% (95%CI: 5.2%, 16.8%) increase in COVID-19. In conclusion, our research results show that Ox and Oxwt can better replace the single pollutant research on O3 and NO2, which is used as a new idea for future epidemiological research.

Big data-based urban greenness in Chinese megalopolises and possible contribution to air quality control

Urban greenness is essential for people's daily lives, while its contribution to air quality control is unclear. In this study, Streetview big data of urban greenness and air quality data (Air Quality Index, PM2.5, PM10, SO2, NO2, O3, CO) from 206 monitoring stations from 27 provincial capital cities in China were analyzed. The national averages for the sky, ground and middle-level (shrub and short trees) view greenness were 5.4%, 5.5%, and 15.4%, respectively, and the sky:ground:middle ratio was 2:2:6. Street-view/bird-view greenness ratio averaged at 1.1. Large inter-city variations were observed in all the greenness parameters, and the weak associations between all street-view parameters and bird-eye greenspace percentage (21%–73%) indicate their representatives of different aspects of green infrastructures. All air quality parameters were higher in winter than in summer, except O3. Over 90% of air quality variation could be explained by socioeconomics and geoclimates, suggesting that air quality control in China should first reduce efflux from social economics, while geoclimatic-oriented ventilation facilitation design is also critical. For different air quality components, greenness had most significant associations with NO2, O3 and CO, and street-view/bird-view ratio was the most powerful indicator of all greenness parameters. Pooled-data analysis at national level showed that street-view greenness was responsible for 2.3% of the air quality variations in the summer and 3.6% in the winter; however, when separated into different regions (North-South China; East-West China), the explaining power increased up to 16.2%. Increased NO2 was accompanied with decreased O3, indicating NO titration effect. The higher O3 aligned with the higher street-view greenness, showing the greenness-related precursor risk for O3 pollution. Our study manifested that big internet data could identify the association of greenness and air pollution from street view scale, which can favor urban greenness management and evaluation in other regions where street-view data are available.

Urinary monohydroxylated polycyclic aromatic hydrocarbons in the general population from 26 provincial capital cities in China: Levels, influencing factors, and health risks.

Polycyclic aromatic hydrocarbons (PAHs) derived from the incomplete combustion of organic materials are associated with adverse health effects. However, little is known about PAH exposure levels and their influencing factors on a large scale in developing countries. In this study, urinary monohydroxylated metabolites of PAHs (OH-PAHs), including the metabolites of naphthalene, fluorene, phenanthrene, pyrene, chrysene, and benzo[a]pyrene, were measured in 1154 samples in the general population nationwide from 26 provincial capitals in China. Concentrations of OH-PAHs ranged from 1.39 to 228μg/L. OH-Nap, metabolite of naphthalene, was the predominant compound, accounting for 65.1% of totals. People in eastern, southwest and northeast China, such as Shanghai, Kunming, Nanning, and Changchun, suffered more PAH exposure than other regions which might associate with sampling time, living habits of the subjects, and the imbalance of economic development and energy consumption across regions. Urinary OH-PAH concentrations were associated with body mass index, gender, and age, and smoking was the main correlating factor. Inhalation and diet might be the main exposure route of human exposure to PAHs, especially for smokers by inhalation. Hazard indices showed that no subject was exposed to PAHs with potential non-carcinogenic risk. Furthermore, the carcinogenic risk was the most significant health effects, with almost all subjects having carcinogenic risk values higher than the acceptable level of 10-6. Naphthalene and phenanthrene were the main contributors. The results also suggested a possible relationship between PAH exposure and lung cancer in the Chinese population. This first nationwide study on human internal exposure to PAHs provides a large body of scientific information for governmental decision-making about associated human health and the prevention of human exposure to PAHs.

National-Scale Urinary Phthalate Metabolites in the General Urban Residents Involving 26 Provincial Capital Cities in China and the Influencing Factors as Well as Non-Carcinogenic Risks

National-Scale Urinary Phthalate Metabolites in the General Urban Residents Involving 26 Provincial Capital Cities in China and the Influencing Factors as Well as Non-Carcinogenic Risks

Government responsiveness and public acceptance of big-data technology in urban governance: Evidence from China during the COVID-19 pandemic

The COVID-19 global pandemic has posed unprecedented challenges to nations and cities worldwide. Governments have adopted Information and Communication Technologies (ICTs) to rapidly control the spread of a novel coronavirus. As an innovative but controversial ICT-based tool, health QR code plays a vital role by assisting rapid contact tracing. Yet, whether and how citizens accept this policy tool remains an unknown theoretical and empirical question. In this paper, we study the sources that determine citizens' acceptance of health QR code in city governance. Based on a nation-wide online survey covering 28 major provincial-capital cities in China, we find that individual experiences and political identities affect citizens' acceptance of QR code. Even though public opinion regarding this issue is diverse, the government's responses to citizens' requests play a critical role in enhancing their acceptance of using QR code both in the current and future stages. Specifically, as the citizens perceive a higher level of city government responsiveness, they are less worried about privacy leaks and more likely to perceive the effectiveness of health QR code in improving public health, thus resulting in a higher acceptance. The results offer broad policy implications for smart cities and urban governance.

Outdoor PM2.5 concentration and rate of change in COVID-19 infection in provincial capital cities in China

This study investigates thoroughly whether acute exposure to outdoor PM2.5 concentration, P, modifies the rate of change in the daily number of COVID-19 infections (R) across 18 high infection provincial capitals in China, including Wuhan. A best-fit multiple linear regression model was constructed to model the relationship between P and R, from 1 January to 20 March 2020, after accounting for meteorology, net move-in mobility (NM), time trend (T), co-morbidity (CM), and the time-lag effects. Regression analysis shows that P (β = 0.4309, p < 0.001) is the most significant determinant of R. In addition, T (β = −0.3870, p < 0.001), absolute humidity (AH) (β = 0.2476, p = 0.002), P × AH (β = −0.2237, p < 0.001), and NM (β = 0.1383, p = 0.003) are more significant determinants of R, as compared to GDP per capita (β = 0.1115, p = 0.015) and CM (Asthma) (β = 0.1273, p = 0.005). A matching technique was adopted to demonstrate a possible causal relationship between P and R across 18 provincial capital cities. A 10 µg/m3 increase in P gives a 1.5% increase in R (p < 0.001). Interaction analysis also reveals that P × AH and R are negatively correlated (β = −0.2237, p < 0.001). Given that P exacerbates R, we recommend the installation of air purifiers and improved air ventilation to reduce the effect of P on R. Given the increasing observation that COVID-19 is airborne, measures that reduce P, plus mandatory masking that reduces the risks of COVID-19 associated with viral-particulate transmission, are strongly recommended. Our study is distinguished by the focus on the rate of change instead of the individual cases of COVID-19 when modelling the statistical relationship between R and P in China; causal instead of correlation analysis via the matching analysis, while taking into account the key confounders, and the individual plus the interaction effects of P and AH on R.

Financial Agglomeration, Energy Efficiency, and Sustainable Development of China’s Regional Economy: Evidence from Provincial Panel Data

Ecological deterioration, air pollution, and resource depletion have shrouded the vast regions of China, raising widespread concerns about the sustainable development of the domestic economy. Although financial agglomeration has become a pivotal approach for China to realize green transformation, there is a lack of evidence against the causal correlation between financial agglomeration and sustainable development of the regional economy. To fill this gap, using the data of 29 provincial capital cities in China spanning from 2009 to 2019 and adopting individual time bidirectional fixed effect model, IV-GMM approach, and alternative modeling techniques, this paper investigates the impact of financial agglomeration on sustainable development of the regional economy for the first time. The results indicate that there is a significant positive correlation between financial agglomeration and the sustainable development of the regional economy. Financial agglomeration facilitates the improvement of regional energy efficiency, and the latter further mediates the relationship between financial agglomeration and sustainable development of the regional economy. In addition, the empirical results also demonstrate that the higher the economic policy uncertainty, the weaker the positive relationship between financial agglomeration and energy efficiency. The present study is of great significance for China to implement energy-saving and emission-reduction tasks and achieve sustainable urban construction.

An Outlier-Robust Point and Interval Forecasting System for Daily PM2.5 Concentration

Air pollution forecasting, particularly of PM2.5 levels, can be used not only to deliver effective warning information to the public but also to provide support for decisions regarding the control and treatment of air pollution problems. However, there are still some challenging issues in air pollution forecasting that urgently need to be solved, such as how to handle and model outliers, improve forecasting stability, and correct forecasting results. In this context, this study proposes an outlier-robust forecasting system to attempt to tackle the abovementioned issues and bridge the gap in the current research. Specifically, the system developed consists of two parts that deal with point and interval forecasting, respectively. For point forecasting, a data preprocessing module is proposed based on outlier handling and data decomposition to mitigate the negative influences of outliers and noise, which can also help the model capture the main characteristics of the original time series. Meanwhile, an outlier-robust forecasting module is designed for better modeling of the preprocessed data. For the model to further improve its accuracy, a nonlinear correction module based on an error ensemble strategy is developed that can provide more accurate forecasting results. Finally, the interval forecasting part of the system is based on a newly proposed artificial intelligence–based distribution evaluation and the results of the point forecasting part to present the range of future changes. Experimental results and analysis utilizing daily PM2.5 concentration from two provincial capital cities in China are discussed to verify the superiority and effectiveness of the system developed, which can be considered an effective technique for point and interval forecasting of daily PM2.5 concentration.