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Source contributions and regional transport of primary particulate matter in China
2015
Hu, Jianlin | Wu, Li | Zheng, Bo | Zhang, Qiang | He, Kebin | Chang, Qing | Li, Xinghua | Yang, Fumo | Ying, Qi | Zhang, Hongliang
A source-oriented CMAQ was applied to determine source sector/region contributions to primary particulate matter (PPM) in China. Four months were simulated with emissions grouped to eight regions and six sectors. Predicted elemental carbon (EC), primary organic carbon (POC), and PPM concentrations and source contributions agree with measurements and have significant spatiotemporal variations. Residential is a major contributor to spring/winter EC (50–80%), POC (60%–90%), and PPM (30–70%). For summer/fall, industrial contributes 30–50% for EC/POC and 40–60% for PPM. Transportation is more important for EC (20–30%) than POC/PPM (<5%). Open burning is important in summer/fall of Guangzhou and Chongqing. Dust contributes to 1/3–1/2 in spring/fall of Beijing, Xi'an and Chongqing. Based on sector–region combination, local residential/transportation and residential/industrial from Heibei are major contributors to spring PPM in Beijing. In summer/fall, local industrial is the largest. In winter, residential/industrial from local and Hebei account for >90% in Beijing.
Show more [+] Less [-]Contrasts in spatial and temporal variability of oxidative capacity and elemental composition in moxibustion, indoor and outdoor environments in Beijing
2015
Huang, Jian | Lim, Min Yee | Hwang, Chaxi | Zhao, Baixiao | Shao, Longyi
Moxibustion is a traditional Chinese medicine therapy that burns moxa floss which produces a substantial amount of PM10 into the environment, thus spawning safety concerns about health impacts of the smoke. We compared the oxidative capacity and elemental composition of moxibustion-derived and ambient PM10 in summer and winter to provide a source-, spatial- and temporal-comparison of PM10 biological responses. The PM10 oxidative capacity was 2.04 and 1.45 fold lower, and dose-dependent slope gradient was 2.36 and 1.76 fold lower in moxibustion environment than indoor or outdoor. Oxidative damage was highly correlated with iron, cesium, aluminum and cobalt in indoor, but moxibustion environment displayed low associations. The total elemental concentration was also lower in moxibustion environment than indoor (2.28 fold) or outdoor (2.79 fold). The source-to-dose modeling and slope gradient analysis in this study can be used as a model for future source-, spatial- and temporal-related moxibustion safety evaluation studies.
Show more [+] Less [-]Polychlorinated naphthalenes (PCNs) in Chinese forest soil: Will combustion become a major source?
2015
Xu, Yue | Li, Jun | Zheng, Qian | Pan, Suhong | Luo, Chunling | Zhu, Haolin | Nizzetto, Luca | Zhang, Gan
We collected O- and A-horizon soil samples in 26 Chinese mountainous forests to investigate the content, spatial pattern, and potential sources of polychlorinated naphthalenes (PCNs). Spatial patterns were influenced mainly by the approximation to sources and soil organic contents. High concentrations often occurred close to populated or industrialized areas. Combustion-related activities contributed to PCN pollution. Relatively high proportions of CN-73 in northern China may be attributed to coke consumption, while CN-51 could be an indicator of biomass burning in Southwest China. There are evidences that PCNs may largely derived from unintentional production. If uncontrolled, UP-PCN (unintentionally produced PCNs) emissions could increase with industrial development. The abnormally high concentrations at Gongga and Changbai Mountains appear to be associated with the high efficient of forest filter of atmospheric contaminants at these densely forested sites. We question whether this is caused by ecotones between forests, and raise additional questions for future analyses.
Show more [+] Less [-]Daily variations of size-segregated ambient particulate matter in Beijing
2015
Zhou, Bangtian | Shen, Huizhong | Huang, Ye | Li, Wei | Chen, Han | Zhang, Yanyan | Su, Shu | Chen, Yuanchen | Lin, Nan | Zhuo, Shaojie | Zhong, Qirui | Liu, Junfeng | Li, Bengang | Tao, Shu
Daily, size-segregated particulate matter (PM) samples were collected at Peking University from March 2012 to April 2013. Seventeen indoor air samples were also collected over this period. Winter PM concentrations decreased compared with those reported a decade ago, but summer PM concentrations increased over the same time period. Increasing summer PM concentrations likely resulted from a shift in the major source of PM from primary coal burning to vehicle-associated secondary particle formation. A multiple regression model explained 62% of daily PM concentration variations, and wind direction was the most important factor controlling PM concentrations. Severe pollution was often associated with southeasterly winds, while westerly and northwesterly winds brought relatively clean air. Temperature, precipitation and relative humidity also affected PM concentrations. PM concentrations indoors were generally lower than, but significantly correlated with ambient concentrations. Indoor PM concentrations were also affected by wind speed and temperature.
Show more [+] Less [-]Distribution and source apportionment of polycyclic aromatic hydrocarbons in surface sediments from Zhoushan Archipelago and Xiangshan Harbor, East China Sea
2015
Wang, Xiaoyan | Xu, Huanzhi | Zhou, Yongdong | Wu, Changwen | Kanchanopas-Barnette, Praparsiri
Zhoushan Archipelago and the adjacent Xiangshan Harbor are important commercial, tourism, fishing, and mariculture areas. Considering the concern on the effects of anthropogenic activities on the environment, the level and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in surface sediments were investigated. The sum of 16 PAH (∑16 PAH) concentrations in the Zhoushan Archipelago ranged from 3.67 to 31.30ngg−1 d.w., with a mean of 15.01±1.21ngg−1 d.w., and that in Xiangshan Harbor varied from 11.58 to 481.44ngg−1 d.w., with a mean of 62.52±32.85ngg−1 d.w. Diagnostic ratios and factor analysis were performed to identify PAH sources. Results show that PAHs have mixed origins (i.e., traffic-related sources, coal combustion, petrogenic sources, and biomass burning), with pyrolytic-related pollution as the dominant source. This study provided a baseline to promote environmental protection and pollution episode monitoring in the East China Sea.
Show more [+] Less [-]Particulate matter sources and long-term trends in a small New Zealand city
2015
Ancelet, Travis | Davy, P. K. (Perry K.) | Trompetter, William J.
Particulate matter samples (PM10 and PM2.5) in downtown Nelson, New Zealand were collected from 2006 to 2012. These samples were used to investigate sources of PM10 and PM2.5, and to evaluate long-term trends in PM10 and BC concentrations. Five PM10 and PM2.5 sources were identified using positive matrix factorization: biomass combustion, motor vehicles, secondary sulfate, marine aerosol and soil. Overall, biomass combustion was the dominant contributor to PM10 (48%) and PM2.5 (77%) mass. The biomass combustion factor profile featured arsenic, suggesting that locals were burning copper chrome arsenate-treated timber, an activity that appears to occur throughout New Zealand.Trend analyses on PM10 and black carbon concentrations revealed that both were decreasing year-on-year, at an average rate of 0.5 μg m−3 per year and 100 ng m−3 per year, respectively. This study provides important information for Nelson City Council, who are responsible for managing air quality in Nelson, to effectively manage air quality. This study also shows that relatively simple mitigation measures can instigate decreases in PM and BC concentrations.
Show more [+] Less [-]Residents’ perception of air quality, pollution sources, and air pollution control in Nanchang, China
2015
Liao, Xiong | Tu, Hong | Maddock, Jay E. | Fan, Si | Lan, Guilin | Wu, Yanyan | Yuan, Zhao Kang | Lu, Yuanan
To assess the public's understanding of the main sources of air pollution in Nanchang and factors influencing their perceptions of Nanchang's air quality status, a face–to–face survey data was collected at the provincial children's hospital and four kindergarten classes in Nanchang. A total of 989 parents with children between the ages of 2 to 10 years old participated in the survey. Among which 69% of respondents believed that the current air quality was worse than three years ago. This study reveals that parents who were under 40 years old of age with higher education level and international travel experience, had higher level awareness of air pollution. Men tend to have lower knowledge of air pollution as compared to women. The top three selected sources of air pollution were motor vehicles (78.5%), waste burning (56.3%) and industrial facilities (53.7%). In addition, 79.8% of respondents believed that the government did not spend enough on environmental protection and 96.8% suggested to increase government funding to improve air quality. The majority of respondents (>90%) strongly urges the Nanchang government to prioritize environmental protection. The findings from this study suggest the need for the government to improve the awareness of the main sources of air pollution, especially to residents of rural areas with lower levels of education, to more effectively and efficiently control air pollution in Nanchang.
Show more [+] Less [-]Biomass burning emissions contaminate winter snowfalls in urban Beijing: A case study in 2012
2015
You, Chao | Gao, Shaopeng | Xu, Chao
Three monosaccharide anhydrides levoglucosan, mannosan and galactosan were detected in winter snowfall samples of 2012 in urban Beijing. Concentrations of three isomers vary from 0.15 to 54.43ngmL−1, with an average value of 10.49ngmL−1. Levoglucosan is the most abundant component. Winter snowfalls are contaminated by biomass burning emissions seriously in urban Beijing. The main sources are softwood and crop residue burnings around Beijing from late autumn to early winter, while long-range transport of biomass burning emissions contribute more during the late winter. Concentrations of monosaccharide anhydrides in snowfall samples may be affected by both topography and the meteorological conditions around urban Beijing.
Show more [+] Less [-]Air Quality in a Cleaner Energy World
2015
Wuebbles, Donald J. | Sanyal, Swarnali
Two major environmental issues, air quality and climate change, are interlinked because of their large dependence on atmospheric emissions from human activities, especially from the burning of fossil fuels. Emission of air pollutants and heat trapping gases have greatly increased over the last five decades from our dependence throughout the world on conventional fossil fuel sources in production of electricity and in transportation systems, resulting in significant environmental issues with air quality and climate change throughout our planet. Future emissions of pollutants will depend on the choices made about our use of energy and transportation. The purpose of this study is to examine for now and into the future the relationship between energy production, the associated use of fossil fuels, and resulting effects on air pollution. In the process, we examine a clean energy future, imagined in this case for 2050, and then consider the resulting potential effects on air quality.
Show more [+] Less [-]Celebration-induced air quality over a tropical urban station, Pune, India
2015
Devara, Panuganti C.S. | Vijayakumar, Katta | Safai, Pramod D. | Made, P Raju | Rao, Pasumarti S.P.
In this paper, we studied the regional aerosol and air quality over an urban location, Pune, India during the period from 8 to 18 November 2012, encompassing a major Indian celebration, namely, Diwali Festival (12–14 November 2012) and also a clean (control) day (9 November 2012). A suit of ground–based measurements, employing solar radiometers (Microtops II and Cimel Sun–sky radiometer), Nephelometer, and satellite observations carried out over the study region have been applied for these investigations. The study revealed many interesting results which include (i) almost four–fold enhancement in AOD and fine mode dominated aerosol size distribution (ASD) during Diwali compared to clean day conditions; (ii) higher columnar water vapor (H2O), nitrogen dioxide (NO2), and lower ozone (O3) during Diwali period; (iii) higher cooling at bottom (–117W m−2) and top of the atmosphere (–33W m−2) and warming (+82W m−2) in the atmosphere during the festival period, (iv) abundance of fine mode anthropogenic scattering particles associated with greater real part and smaller imaginary part of refractive index, and higher single scattering albedo, (v) higher backscattering coefficient revealing intrusion of more aerosol particles, higher depolarization ratio indicating particles of non–spherical nature, presence of water–phase particles, more polluted smoke and dust particles, (vi) greater attenuation and poor horizontal/vertical visibility, and (vii) dominance of urban industrial/biomass burning aerosols among other aerosol types. These results have been compared with concurrent satellite products and found to be consistent. The results have been further explained with local meteorology, back–trajectory analysis and satellite rapid response images.
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