Seasonal variations and source apportionment of carbonaceous aerosol in PM2.5 from a coal mining city in the North China Plain

Handan is one of the most polluted coal mining cities in the North China Plain (NCP). There is a lack of research on the pollution characteristics and sources of carbonaceous components in PM2.5 in Handan city. Atmospheric PM2.5 samples were collected from Handan City during 2018 and the organic carbon (OC) and elemental carbon (EC) in PM2.5 were analyzed with a carbon analyzer. The annual average mass concentrations of PM2.5 and total carbon (TC = OC + EC) in Handan were (101.88 ± 79.01) μg/m3 and (28.03 ± 23.28) μg/m3, respectively. The annual average ratio of TC/PM2.5 was (28.29% ± 7.95%), indicating that carbonaceous components made a major contribution to PM2.5. The seasonal variations of OC and EC concentrations in PM2.5 were consistent with PM2.5, which was higher in winter and lower in summer. The annual average OC/EC ratio was (10.33 ± 5.83), and the (OC/EC)min ratio for each season was greater than 2, suggesting that there was probably secondary organic carbon (SOC) formation all around the year. The correlations between OC and EC during spring and winter were much more significant than during summer and autumn, which indicated that the sources of OC and EC in summer and autumn were more complex. Principal component analysis (PCA) displayed that the main sources of carbonaceous components in PM2.5 were coal combustion emission, road dust and vehicle exhaust, which may be related to coal-fired power generation and steelmaking, and coal transportation in Handan city. The potential source contribution function (PSCF) analysis demonstrated that PM2.5 and carbonaceous components in Handan city were significantly influenced by both local emissions and regional transport during the observation period.

Source Apportionment and Health Risk Assessment of Heavy Metals in PM2.5 in Handan: A Typical Heavily Polluted City in North China

In order to determine the pollution sources and human health risks of metal elements in PM2.5, samples were collected by a large flow particulate matter sampler in the four seasons in 2013, 2015, and 2017 (January, April, July, and October). The mass concentrations of 10 metals (Ti, V, Cr, Mn, Ni, Cu, Zn, As, Cd, and Pb) were analyzed. The sources of heavy metals were identified by Unmix, and the potential non-carcinogenic/carcinogenic risk was evaluated. The influences of local and regional sources were also explored during the high-carcinogenic risk period (HCRP). The wind field and 72 h backward trajectories were performed to identify the potential local and regional sources in HCRP. The results showed that the average annual concentrations of PM2.5 in the urban area of Handan city were 105.14, 91.18, and 65.85 μg/m3 in 2013, 2015, and 2017, respectively. The average daily concentrations of the metals in PM2.5 in January were higher than that of April, July, and October. The average mass concentrations of the 10 heavy metal elements in PM2.5 were 698.26, 486.92, and 456.94 ng·m−3 in 2013, 2015, and 2017, respectively. The main sources of the metals in PM2.5 were soil dust sources, vehicular emissions, coal burning, and industrial activities. The carcinogenic risks of Cr and As were above 1 × 10−6 over the three years. Wind direction analysis showed that the potential local sources were heavy industry enterprises and the economic development zone. The backward trajectory analysis indicated that PM2.5 long transported from Shandong, Henan, and the surrounding cities of Handan had quite an impact on the heavy metals contained in the atmosphere of the studied area. The health risk assessment results demonstrated that the trend for non-carcinogenic risk declined, and there was no non-carcinogenic risk in 2017. However, the carcinogenic risk levels were high over the three years, particularly in January.

Contributions of Land Utilization Differences and Changes in Zhongyuan Urban Agglomeration to Regional Thermal Environment

Accelerated urbanization has given rise to sharp environmental changes in urban underlying surfaces, thus changing the regional thermal environment and endangering the ecosystem balance. The thermal environment is complex, and the influence laws of land utilization differences and changes in the thermal environment in different seasons and under different daytime and nighttime conditions are unclear. In this regard, effective measures should be implemented to reduce the regional thermal environmental effect and determine the influence laws of land utilization differences and changes in the regional thermal environment. Zhongyuan urban agglomeration was applied as the study area. Two-year MODIS eight-day synthesized surface temperature product and land utilization monitoring data were obtained by remote sensing and used to analyze the influencing characteristics of different cities and land utilization types on the thermal environment of urban agglomeration from the angles of interannual differences and seasonal differences. During 2010-2018, the area changes in different land utilization types in the study area are significant with decreasing farmland area and increasing forest land and construction land. The farmland and forest land have the most significant influences on the regional thermal environment, where the farmland exerts a warming effect on the regional thermal environment and the forest land exerts a cooling effect. In different seasons and under different daytime and nighttime conditions, the construction land shows a strong warming effect on the regional thermal environment. The contribution indices of Changzhi city and Jincheng city to the thermal environment of the urban agglomeration are negative, so they exert the cooling effect. The warming or cooling role played by Handan city, Liaocheng city, and Xingtai city in the thermal environment is transited under different daytime and nighttime conditions, namely, they exert the warming effect in the day

Analysis of Epidemiological Changes and Elimination Effects for Malaria in North China

Backgroud: The elimination of malaria requires high-quality surveillance data in order to detect and respond quickly to individual cases. In the 1960s and 1970s, Handan city in North China experienced widespread malaria outbreaks, which was in line with the provincial and national epidemic patterns. Methods: Case-level data for the period 2011-2018 were extracted from China's National Infectious Diseases Information system and the rest cases were recorded municipal surveillance system from 1956-2010.Results: The incidence, accuracy and timeliness of case diagnosis, reporting and investigation in malaria were evaluated at elimination stage (2011-2018) in Handan city, China. From 2011 to 2018, 81 malaria cases were reported in Handan city, all of which were imported from abroad. The annual average incidence decreased to 0.11/100 000 in the elimination stage, while all malaria cases were male. Since the initiation of the National Malaria Elimination Programme in 2010, malaria cases were consistent with the increase in overseas export channels and personnel of labor services.Conclusions: The case-based malaria surveillance system in North China worked well at the malaria elimination stage. This ensured that malaria cases could be diagnosed, reported and timely investigated at local level.

Seasonal variations and risk assessment of heavy metals in PM2.5 from Handan, China

Purpose This study aims to acquire a better understanding on the characteristics and risks of heavy metals (HMs) in PM2.5 from an industrial city – Handan, China. Design/methodology/approach PM2.5 samples were collected on the basis of daytime and nighttime at the state controlling air sampling site in Handan city. Ten metal elements (V, Cr, Mn, Fe, Ni, Cu, Rb, Sr, Cd and Ba) in PM2.5 were determined with an inductively coupled plasma mass spectrometry. The pollution levels of metals were characterized by enrichment factors, and the sources of metals were identified with principle component analysis and cluster analysis. The ecological and health risks of metals were assessed using ecological and health risk indexes. Findings Results showed that the highest and lowest PM2.5 concentration appeared in winter and summer, respectively. The concentration of PM2.5 at night was higher than in the daytime in winter, yet it is the opposite in other seasons. The total mass concentration of detected metals was the highest in winter, and the total mass concentration in the daytime was higher than at night in all four seasons. The elements V, Rb, Sr and Ba exhibited a deficient contamination level; Cr, Ni and Cu exhibited a moderate contamination level; while Fe and Cd were at an extreme contamination level. The metals in PM2.5 originated from a mixture source of fossil fuel combustion and manufacture and use of metallic substances (34.04%), natural source (26.01%) and construction and traffic-related road dust (17.58%). Results from the ecological risk model showed that the ecological risk of metals was very high, especially risks related to Cd. Health risk model presented that both the non-carcinogenic and carcinogenic risk coefficients of metals were above the tolerance level of the human body. Originality/value The significance of the study is to further know the pollution characteristics of PM2.5 and related HMs in Handan city, and to provide references for ensuring local resident health and ecological environment.

Analysis of epidemiological changes and elimination effects for malaria in Handan city, China

Backgroud: The elimination of malaria requires high-quality surveillance data in order to detect and respond quickly to individual cases. In the 1960s and 1970s, Handan city experienced widespread malaria outbreaks, which was in line with the provincial and national epidemic patterns. Methods: Case-level data for the period 2011-2018 were extracted from China's National Infectious Diseases Information system and the rest cases were recorded municipal surveillance system from 1956-2010. Results: The incidence, accuracy and timeliness of case diagnosis, reporting and investigation in malaria were evaluated at elimination stage (2011-2018) in Handan city, China. From 2011 to 2018, 81 malaria cases were reported in Handan city, all of which were imported from abroad. The annual average incidence decreased to 0.11/100 000 in the elimination stage, while all malaria cases were male. Since the initiation of the National Malaria Elimination Programme in 2010, malaria cases were consistent with the increase in overseas export channels and personnel of labor services. Conclusions: The case-based malaria surveillance system in Handan worked well at the malaria elimination stage. This ensured that malaria cases could be diagnosed, reported and timely investigated at local level.

Analysis of Epidemiological Changes and Elimination Effects for Malaria in Handan City, China

Background: The elimination of malaria requires high-quality surveillance data in order to detect and respond quickly to individual cases. In the 1960s and 1970s, Handan city experienced widespread malaria outbreaks, which was in line with the provincial and national epidemic patterns. Methods: Case-level data for the period 2011-2018 were extracted from China's National Infectious Diseases Information system and the rest cases were recorded municipal surveillance system from 1956-2010. Results: The incidence, accuracy and timeliness of case diagnosis, reporting and investigation in malaria were evaluated at elimination stage (2011-2018) in Handan city, China. From 2011 to 2018, 81 malaria cases were reported in Handan city, all of which were imported from abroad. The annual average incidence decreased to 0.11/100 000 in the elimination stage, while all malaria cases were male. Since the initiation of the National Malaria Elimination Programme in 2010, malaria cases were consistent with the increase in overseas export channels and personnel of labor services. Conclusions: The case-based malaria surveillance system in Handan worked well at the malaria elimination stage. This ensured that malaria cases could be diagnosed, reported and timely investigated at local level.

Economic, Social, and Ecological Impact Evaluation of Traffic Network in Beijing–Tianjin–Hebei Urban Agglomeration Based on the Entropy Weight TOPSIS Method

In recent years, with the rapid development of urban transportation network in China, many problems have been exposed, especially in the Beijing–Tianjin–Hebei (BTH) region. Under the call of sustainable development, it is of great significance to evaluate the economic, social, and ecological (ESE) impact of transportation network in BTH urban agglomeration for promoting the sustainable development of transportation ESE in BTH urban agglomeration. In this paper, 12 indicators in the field of transportation are selected to build the evaluation index system of ESE effects of transportation network in BTH urban agglomeration. By using entropy weight TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) model and the Jenks natural breaks classification method, the ESE impacts of transportation network in 13 cities of BTH from 2013 to 2017 are analyzed from the temporal and spatial dimensions. The research shows that: (1) From 2013 to 2017, the economic impact degree of traffic network shows an annual fluctuation trend, the social impact degree increases year by year, and the ecological impact degree decreases year by year; (2) For the cities of BTH, the ESE impact assessment results of transportation network from 2013 to 2017 can be divided into seven clusters. Except Handan City, the ESE impact assessment categories of other cities’ transportation network have been improved, but the proportion of cities in the transition period is still large, especially the “Low-Low-Low” cities. The types of cities in the transitional period need to be focused. It is still a heavy burden to realize the ESE coordination and sustainable development of BTH urban agglomeration transportation network.