As the world's most populous country,China has witnessed rapid urbanization in recent decades,with population migration from rural to urban(RU)regions as the major driving force.Due to the large gap between rural ...As the world's most populous country,China has witnessed rapid urbanization in recent decades,with population migration from rural to urban(RU)regions as the major driving force.Due to the large gap between rural and urban consumption and investment level,large-scale RU migration impacts air pollutant emissions and creates extra uncertainties for air quality improvement.Here,we integrated population migration assessment,an environmentally extended inputeoutput model and structural decomposition analysis to evaluate the NOx,SO2 and primary PM2.5 emissions induced by RU migration during China's urbanization from 2005 to 2015.The results show that RU migration increased air pollutant emissions,while the increases in NOx and SO2 emissions peaked in approximately 2010 at 2.4 Mt and 2.2 Mt,accounting for 9.2%and 8.7%of the national emissions,respectively.The primary PM2.5 emissions induced by RU migration also peaked in approximately 2012 at 0.3 Mt,accounting for 2.8%of the national emissions.The indirect emissions embodied in consumption and investment increased,while household direct emissions decreased.The widening gap between urban and rural investment and consumption exerted a major increasing effect on migration-induced emissions;in contrast,the falling emission intensity contributed the most to the decreasing effect benefitting from end-of-pipe control technology applications as well as improving energy efficiency.The peak of air pollutant emissions induced by RU migration indicates that although urbanization currently creates extra environmental pressure in China,it is possible to reconcile urbanization and air quality improvement in the future with updating urbanization and air pollution control policies.展开更多
The high-speed rail(HSR)network in China has experienced rapid development since the 2000s.In 2016,the State Council of the People’s Republic of China issued a revised version of the“Mid-and Long-term Railway Networ...The high-speed rail(HSR)network in China has experienced rapid development since the 2000s.In 2016,the State Council of the People’s Republic of China issued a revised version of the“Mid-and Long-term Railway Network Plan”,detailing the expansion of the railway network and construction of an HSR system.In the future,the HSR construction efforts in China will further increase,which is considered to impact regional development and air pollutant emissions.Therefore,in this paper,we apply a transportation network-multiregional computable general equilibrium(CGE)model to estimate the dynamic effects of HSR projects on economic growth,regional disparities,and air pollutant emissions in China.The results indicate that HSR system improvement could generate a positive economic impact but could also increase emissions.The gross domestic product(GDP)growth per unit investment cost stimulated by HSR investment is found to be the largest in eastern China but the smallest in the northwest regions.Conversely,HSR investment in Northwest China contributes to a substantial reduction in regional disparities in terms of the GDP per capita.In regard to air pollution emissions,HSR construction in South-Central China results in the largest increase in CO_(2) and NO_(X) emissions,while for CO,SO_(2),and fine particulate matter(PM_(2.5))emissions,the largest increase occurs due to HSR construction in Northwest China.At the regional level,the provinces with large changes in accessibility also experience large changes in their air pollutant emissions.展开更多
Air pollution is a major issue related to national economy and people's livelihood.At present,the researches on air pollution mostly focus on the pollutant emissions in a specific industry or region as a whole,and...Air pollution is a major issue related to national economy and people's livelihood.At present,the researches on air pollution mostly focus on the pollutant emissions in a specific industry or region as a whole,and is a lack of attention to enterprise pollutant emissions from the micro level.Limited by the amount and time granularity of data from enterprises,enterprise pollutant emissions are stll understudied.Driven by big data of air pollution emissions of industrial enterprises monitored in Beijing-Tianjin-Hebei,the data mining of enterprises pollution emissions is carried out in the paper,including the association analysis between different features based on grey association,the association mining between different data based on association rule and the outlier detection based on clustering.The results show that:(1)The industries affecting NOx and SO2 mainly are electric power,heat production and supply industry,metal smelting and processing industries in Beijing-Tianjin-Hebei;(2)These districts nearby Hengshui and Shijiazhuang city in Hebei province form strong association rules;(3)The industrial enterprises in Beijing-Tianjin-Hebei are divided into six clusters,of which three categories belong to outliers with excessive emissions of total vOCs,PM and NH3 respectively.展开更多
Biomass is considered a renewable and cleaner energy source alternative to fossil fuels.In recent years,industrial biomass boilers have been rapidly developed and widely used in the industrial field.This work makes a ...Biomass is considered a renewable and cleaner energy source alternative to fossil fuels.In recent years,industrial biomass boilers have been rapidly developed and widely used in the industrial field.This work makes a review on the fuel types used in industrial biomass boilers,the fuel characteristics and the characteristics of air pollutants emitted from the combustion of industrial biomass boilers and other contents in different studies.However,the existing research still has many deficiencies.In the future,further research on biomass fuel,industrial biomass boiler combustion process and the pollutants emitted by industrial biomass boiler combustion,especially the carbonaceous aerosol emitted by in-dustrial biomass boiler and carbonaceous aerosol optical properties still need to be made.At the same time,the potential harm of carbonaceous aerosols emitted from industrial biomass boiler sources to human health and climate change needs to be studied in depth.This review provides a scientific basis for the accurate evaluation of industrial biomass boilers and the effective prevention and control of various pollutants of industrial biomass boilers.展开更多
Residential low efficient fuel burning is a major source of many air pollutants produced during incomplete combustions, and household air pollution has been identified as one of the top environmental risk factors. Her...Residential low efficient fuel burning is a major source of many air pollutants produced during incomplete combustions, and household air pollution has been identified as one of the top environmental risk factors. Here we compiled literature-reported emission factors of pollutants including carbon monoxide(CO), total suspended particles(TSPs), PM2.5, organic carbon(OC),elemental carbon(EC) and polycyclic aromatic hydrocarbons(PAHs) for different household energy sources, and quantified the potential for emission reduction by clean fuel adoption. The burning of crop straws, firewood and coal chunks in residential stoves had high emissions per unit fuel mass but lower thermal efficiencies, resulting in high levels of pollution emissions per unit of useful energy, whereas pelletized biofuels and coal briquettes had lower pollutant emissions and higher thermal efficiencies. Briquetting coal may lead to 82%–88% CO, 74%–99%TSP, 73%–76% PM2.5, 64%–98% OC, 92%–99% EC and 80%–83% PAH reductions compared to raw chunk coal. Biomass pelletizing technology would achieve 88%–97% CO, 73%–87% TSP, 79%–88%PM2.5, 94%–96% OC, 91%–99% EC and 63%–96% PAH reduction compared to biomass burning. The adoption of gas fuels(i.e., liquid petroleum gas, natural gas) would achieve significant pollutant reduction, nearly 96% for targeted pollutants. The reduction is related not only to fuel change, but also to the usage of high efficiency stoves.展开更多
‘Co-control',or synergistically reducing CO_(2)and local air polluta nt emissions,is an important strategy for cities to achieve'low carb on'and'blue sky'simultaneously.However,there were few stud...‘Co-control',or synergistically reducing CO_(2)and local air polluta nt emissions,is an important strategy for cities to achieve'low carb on'and'blue sky'simultaneously.However,there were few studies to evaluate and compare the level of co-control of CO_(2) and local air pollutants in cities year.The present study proposed qualitative and quantitative methods to evaluate the level of co-control of CO_(2)and three local air pollutant(SO_(2).NOX,and particulate matter PM)emissions in key environmental protection cities in China over two periods(2012-2015 and 2015-2018).Statistical analysis found that,though three local air pollutant emissions positively correlated with CO_(2) emission,no significantly positive correlation was found between local air pollutants emission reductions and CO_(2) emission reductions,indicating that co-control effects were poor in general.By using the co-control effect coordinate system,qualitative evaluation showed that less than half of the sample cities could achieve co-control of the total amount of CO_(2) and local air pollutants.By employing the indicator of emission reduction equivalence(EReq),quantitative evaluation showed that the co-control level of the sample cities improved in 2015-2018 compared with 2012-2015.Further regression analysis showed that,reducing coal consumption and economic development significantly enhanced the co-control performance of the observed cities.The present case study proved that the proposed methods for evaluation and comparison of the city co-control performance works well,and can be used in other countries and regions to promote global cities racing to carbon and local air pollutants co-control.展开更多
The national Air Pollution Prevention and Control Action Plan required significant decreases in PM_(2.5) levels over China.To explore more effective emission abatement strategies in industrial cities,a case study wa...The national Air Pollution Prevention and Control Action Plan required significant decreases in PM_(2.5) levels over China.To explore more effective emission abatement strategies in industrial cities,a case study was conducted in Baotou to evaluate the current national control measures.The total emissions of SO_2,NO_X,PM_(2.5) and NMVOC(non-methane volatile organic compounds) in Baotou were 211.2 Gg,156.1 Gg,28.8 Gg,and 48.5 Gg,respectively in 2013,and they would experience a reduction of 30.4%,26.6%,15.1%,and 8.7%,respectively in 2017 and 39.0%,32.0%,24.4%,and 12.9%,respectively in2020.The SO_2,NO_Xand PM_(2.5) emissions from the industrial sector would experience a greater decrease,with reductions of 37%,32.7 and 24.3%,respectively.From 2013 to 2020,the concentrations of SO_2,NO_2,and PM_(2.5) are expected to decline by approximately 30%,10% and 14.5%,respectively.The reduction rate of SNA(sulfate,nitrate and ammonium)concentrations was significantly higher than that of PM_(2.5) in 2017,implying that the current key strategy toward controlling air pollutants from the industrial sector is more powerful for SNA.Although air pollution control measures implemented in the industrial sector could greatly reduce total emissions,constraining the emissions from lower sources such as residential coal combustion would be more effective in decreasing the concentration of PM_(2.5) from 2017 to 2020.These results suggest that even for a typical industrial city,the reduction of PM_(2.5) concentrations not only requires decreases in emissions from the industrial sector,but also from the low emission sources.The seasonal variation in sulfate concentration also showed that emission from coal-burning is the key factor to control during the heating season.展开更多
Emissions of mineral dust and its mixing with anthropogenic air pollutants affect both regional and global climates. Our fieldwork in late spring 2007(April 25-June 15) measured the physical and optical properties o...Emissions of mineral dust and its mixing with anthropogenic air pollutants affect both regional and global climates. Our fieldwork in late spring 2007(April 25-June 15) measured the physical and optical properties of dust storms mixed with local air pollutants at a rural site about 48 km southeast of central Lanzhou. Levels of air pollutants and aerosol optical properties were observed during the experiment, with concentrations of NOx(6.8 ± 3.3 ppb, average ± standard deviation), CO(694 ± 486 ppb), SO2(6.2 ±10 ppb), O3(50.7 ± 13.1 ppb), and PM10(172 ± 180 μg m-3), and aerosol scattering coefficient(164 ±89 Mm-1; 1 Mm = 106m) and absorption coefficient(11.7 ± 6.6 Mm-1), all much lower than the values observed during air pollution episodes in urban areas. During a major dust storm, the mass concentration of PM10 reached 4072 μg m-3, approximately 21-fold higher than in non-dust storm periods. The mixing ratios of trace gases declined noticeably after a cold front passed through. The observed CO/SO2 and CO/NOx ratios during air pollution episodes were 4.2-18.3 and 13.7-80.5, respectively, compared with the corresponding ratios of 38.1-255.7 and 18.0-245.9 during non-pollution periods. Our investigations suggest that dust storms have a significant influence on air quality in areas far from their source, and this large-scale transport of dust and air pollutants produces major uncertainties in the quantification of the global effects of emissions over Northwest China.展开更多
Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Comm...Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.展开更多
A three-year sampling campaign was conducted at a roadside air pollution monitoring station in the urban area of Kanazawa, Japan. Due to a new emission regulation, PAHs levels decreased over the sampling campaign, exh...A three-year sampling campaign was conducted at a roadside air pollution monitoring station in the urban area of Kanazawa, Japan. Due to a new emission regulation, PAHs levels decreased over the sampling campaign, exhibiting values of 706 ± 413 pg/m^(3) in 2017, 559 ±384 pg/m^(3) in 2018, and 473 ± 234 pg/m^(3) in 2019. In each year, similar seasonal variations in PAHs levels were observed, with higher levels observed in winter and lower levels in summer. Among the PAHs isomer ratios, we observed that the ratio of benzo[b]fluoranthene(BbF) and benzo[k]fluoranthene(BkF), [Bb F]/([BbF] + [BkF]), and the ratio of indeno[1,2,3-cd]pyrene(IDP) and benzo[ghi]perylene(BgPe), [IDP]/([BgPe] + [IDP]), showed stability over the sampling campaign and were less affected by the new emission regulation, seasonal variations, and regional characteristics. When using the combined ratio ranges of 0.66-0.80([Bb F]/[BbF] + [BkF]) and 0.26-0.49([IDP]/[Bg Pe] + [IDP]), traffic emissions were clearly distinguished from other PAHs emission sources. Principal component analysis(PCA) and positive matrix factorization(PMF) were also performed to further analyse the characteristics of traffic-related PAHs. Overall, this study affirmed the effectiveness of the new emission regulation in the reduction of PAHs emissions and provided a combined range for identifying PAHs traffic emission sources.展开更多
We investigated variations of PM_(2.5)and water-soluble inorganic ions chemical characteristics at nine urban and rural sites in China using ground-based observations.From 2015 to 2019,mean PM_(2.5)concentration acros...We investigated variations of PM_(2.5)and water-soluble inorganic ions chemical characteristics at nine urban and rural sites in China using ground-based observations.From 2015 to 2019,mean PM_(2.5)concentration across all sites decreased by 41.9μg/m~3with a decline of 46%at urban sites and 28%at rural sites,where secondary inorganic aerosol(SIAs)contributed to 21%(urban sites)and 17%(rural sites)of the decreased PM_(2.5).SIAs concentrations underwent a decline at urban locations,while sulfate(SO_(4)^(2–)),nitrate(NO_(3)^(–)),and ammonium(NH_(4)^(+))decreased by 49.5%,31.3%and 31.6%,respectively.However,only SO_(4)^(2–)decreased at rural sites,NO_(3)^(–)increased by 21%and NH_(4)^(+)decreased slightly.Those changes contributed to an overall SIAs increase in 2019.Higher molar ratios of NO_(3)^(–)to SO_(4)^(2–)and NH_(4)^(+)to SO_(4)^(2–)were observed at urban sites than rural sites,being highest in the heavily polluted days.Mean molar ratios of NH_(3)/NH_xwere higher in 2019 than 2015 at both urban and rural sites,implying increasing NH_xremained as free NH_(3).Our observations indicated a slower transition from sulfate-driven to nitrate-driven aerosol pollution and less efficient control of NO_(x)than SO_(2)related aerosol formation in rural regions than urban regions.Moreover,the common factor at urban and rural sites appears to be a combination of lower SO_(4)^(2–)levels and an increasing fraction of NO_(3)^(–)to PM_(2.5)under NH_(4)^(+)-rich conditions.Our findings imply that synchronous reduction in NO_(x)and NH_(3)emissions especially rural areas would be effective to mitigate NO_(3)^(–)-driven aerosol pollution.展开更多
基金the National Natural Science Foundation of China(No.72025401,71974108,and 71690244)the Tsinghua University-Inditex Sustainable Development Fund.
文摘As the world's most populous country,China has witnessed rapid urbanization in recent decades,with population migration from rural to urban(RU)regions as the major driving force.Due to the large gap between rural and urban consumption and investment level,large-scale RU migration impacts air pollutant emissions and creates extra uncertainties for air quality improvement.Here,we integrated population migration assessment,an environmentally extended inputeoutput model and structural decomposition analysis to evaluate the NOx,SO2 and primary PM2.5 emissions induced by RU migration during China's urbanization from 2005 to 2015.The results show that RU migration increased air pollutant emissions,while the increases in NOx and SO2 emissions peaked in approximately 2010 at 2.4 Mt and 2.2 Mt,accounting for 9.2%and 8.7%of the national emissions,respectively.The primary PM2.5 emissions induced by RU migration also peaked in approximately 2012 at 0.3 Mt,accounting for 2.8%of the national emissions.The indirect emissions embodied in consumption and investment increased,while household direct emissions decreased.The widening gap between urban and rural investment and consumption exerted a major increasing effect on migration-induced emissions;in contrast,the falling emission intensity contributed the most to the decreasing effect benefitting from end-of-pipe control technology applications as well as improving energy efficiency.The peak of air pollutant emissions induced by RU migration indicates that although urbanization currently creates extra environmental pressure in China,it is possible to reconcile urbanization and air quality improvement in the future with updating urbanization and air pollution control policies.
基金supported by funding from the National Natural Science Foundation of China(Nos.41821005 and 42077196).
文摘The high-speed rail(HSR)network in China has experienced rapid development since the 2000s.In 2016,the State Council of the People’s Republic of China issued a revised version of the“Mid-and Long-term Railway Network Plan”,detailing the expansion of the railway network and construction of an HSR system.In the future,the HSR construction efforts in China will further increase,which is considered to impact regional development and air pollutant emissions.Therefore,in this paper,we apply a transportation network-multiregional computable general equilibrium(CGE)model to estimate the dynamic effects of HSR projects on economic growth,regional disparities,and air pollutant emissions in China.The results indicate that HSR system improvement could generate a positive economic impact but could also increase emissions.The gross domestic product(GDP)growth per unit investment cost stimulated by HSR investment is found to be the largest in eastern China but the smallest in the northwest regions.Conversely,HSR investment in Northwest China contributes to a substantial reduction in regional disparities in terms of the GDP per capita.In regard to air pollution emissions,HSR construction in South-Central China results in the largest increase in CO_(2) and NO_(X) emissions,while for CO,SO_(2),and fine particulate matter(PM_(2.5))emissions,the largest increase occurs due to HSR construction in Northwest China.At the regional level,the provinces with large changes in accessibility also experience large changes in their air pollutant emissions.
基金supported by the National Natural Science Foundation of China[grant number 72271033]the Beijing Municipal Education Commission and Beijing Natural Science Foundation[grant number KZ202110017025]the National Undergraduate Innovation and Entrepreneurship Plan Project(2022J00244).
文摘Air pollution is a major issue related to national economy and people's livelihood.At present,the researches on air pollution mostly focus on the pollutant emissions in a specific industry or region as a whole,and is a lack of attention to enterprise pollutant emissions from the micro level.Limited by the amount and time granularity of data from enterprises,enterprise pollutant emissions are stll understudied.Driven by big data of air pollution emissions of industrial enterprises monitored in Beijing-Tianjin-Hebei,the data mining of enterprises pollution emissions is carried out in the paper,including the association analysis between different features based on grey association,the association mining between different data based on association rule and the outlier detection based on clustering.The results show that:(1)The industries affecting NOx and SO2 mainly are electric power,heat production and supply industry,metal smelting and processing industries in Beijing-Tianjin-Hebei;(2)These districts nearby Hengshui and Shijiazhuang city in Hebei province form strong association rules;(3)The industrial enterprises in Beijing-Tianjin-Hebei are divided into six clusters,of which three categories belong to outliers with excessive emissions of total vOCs,PM and NH3 respectively.
基金supported by the National Natural Science Foundation of China(grant Nos.42265011,41765009,and 52064037)the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province,China(grant No.20212BCJL23054)。
文摘Biomass is considered a renewable and cleaner energy source alternative to fossil fuels.In recent years,industrial biomass boilers have been rapidly developed and widely used in the industrial field.This work makes a review on the fuel types used in industrial biomass boilers,the fuel characteristics and the characteristics of air pollutants emitted from the combustion of industrial biomass boilers and other contents in different studies.However,the existing research still has many deficiencies.In the future,further research on biomass fuel,industrial biomass boiler combustion process and the pollutants emitted by industrial biomass boiler combustion,especially the carbonaceous aerosol emitted by in-dustrial biomass boiler and carbonaceous aerosol optical properties still need to be made.At the same time,the potential harm of carbonaceous aerosols emitted from industrial biomass boiler sources to human health and climate change needs to be studied in depth.This review provides a scientific basis for the accurate evaluation of industrial biomass boilers and the effective prevention and control of various pollutants of industrial biomass boilers.
基金Funding for the study was supported by the United Nation Foundation (No. RFP 13-1)the National Natural Science Foundation (No. 41301554)Jiangsu Natural Science Foundation (No. BK20131031)
文摘Residential low efficient fuel burning is a major source of many air pollutants produced during incomplete combustions, and household air pollution has been identified as one of the top environmental risk factors. Here we compiled literature-reported emission factors of pollutants including carbon monoxide(CO), total suspended particles(TSPs), PM2.5, organic carbon(OC),elemental carbon(EC) and polycyclic aromatic hydrocarbons(PAHs) for different household energy sources, and quantified the potential for emission reduction by clean fuel adoption. The burning of crop straws, firewood and coal chunks in residential stoves had high emissions per unit fuel mass but lower thermal efficiencies, resulting in high levels of pollution emissions per unit of useful energy, whereas pelletized biofuels and coal briquettes had lower pollutant emissions and higher thermal efficiencies. Briquetting coal may lead to 82%–88% CO, 74%–99%TSP, 73%–76% PM2.5, 64%–98% OC, 92%–99% EC and 80%–83% PAH reductions compared to raw chunk coal. Biomass pelletizing technology would achieve 88%–97% CO, 73%–87% TSP, 79%–88%PM2.5, 94%–96% OC, 91%–99% EC and 63%–96% PAH reduction compared to biomass burning. The adoption of gas fuels(i.e., liquid petroleum gas, natural gas) would achieve significant pollutant reduction, nearly 96% for targeted pollutants. The reduction is related not only to fuel change, but also to the usage of high efficiency stoves.
基金This work was co-supported by The Energy Foundation project‘Co-control effect assessment of deep decarbonization measures and the co-control path way in China'(G-1809-28536)the Major Projects of the National Social Science Foundation‘Study on action plan for peaking carbon emissions by 2030 in China'(21ZDA085).
文摘‘Co-control',or synergistically reducing CO_(2)and local air polluta nt emissions,is an important strategy for cities to achieve'low carb on'and'blue sky'simultaneously.However,there were few studies to evaluate and compare the level of co-control of CO_(2) and local air pollutants in cities year.The present study proposed qualitative and quantitative methods to evaluate the level of co-control of CO_(2)and three local air pollutant(SO_(2).NOX,and particulate matter PM)emissions in key environmental protection cities in China over two periods(2012-2015 and 2015-2018).Statistical analysis found that,though three local air pollutant emissions positively correlated with CO_(2) emission,no significantly positive correlation was found between local air pollutants emission reductions and CO_(2) emission reductions,indicating that co-control effects were poor in general.By using the co-control effect coordinate system,qualitative evaluation showed that less than half of the sample cities could achieve co-control of the total amount of CO_(2) and local air pollutants.By employing the indicator of emission reduction equivalence(EReq),quantitative evaluation showed that the co-control level of the sample cities improved in 2015-2018 compared with 2012-2015.Further regression analysis showed that,reducing coal consumption and economic development significantly enhanced the co-control performance of the observed cities.The present case study proved that the proposed methods for evaluation and comparison of the city co-control performance works well,and can be used in other countries and regions to promote global cities racing to carbon and local air pollutants co-control.
基金supported by the Special Scientific Research Fund of the Environmental Protection Commonwealth Section(Nos.201409003,201509020)
文摘The national Air Pollution Prevention and Control Action Plan required significant decreases in PM_(2.5) levels over China.To explore more effective emission abatement strategies in industrial cities,a case study was conducted in Baotou to evaluate the current national control measures.The total emissions of SO_2,NO_X,PM_(2.5) and NMVOC(non-methane volatile organic compounds) in Baotou were 211.2 Gg,156.1 Gg,28.8 Gg,and 48.5 Gg,respectively in 2013,and they would experience a reduction of 30.4%,26.6%,15.1%,and 8.7%,respectively in 2017 and 39.0%,32.0%,24.4%,and 12.9%,respectively in2020.The SO_2,NO_Xand PM_(2.5) emissions from the industrial sector would experience a greater decrease,with reductions of 37%,32.7 and 24.3%,respectively.From 2013 to 2020,the concentrations of SO_2,NO_2,and PM_(2.5) are expected to decline by approximately 30%,10% and 14.5%,respectively.The reduction rate of SNA(sulfate,nitrate and ammonium)concentrations was significantly higher than that of PM_(2.5) in 2017,implying that the current key strategy toward controlling air pollutants from the industrial sector is more powerful for SNA.Although air pollution control measures implemented in the industrial sector could greatly reduce total emissions,constraining the emissions from lower sources such as residential coal combustion would be more effective in decreasing the concentration of PM_(2.5) from 2017 to 2020.These results suggest that even for a typical industrial city,the reduction of PM_(2.5) concentrations not only requires decreases in emissions from the industrial sector,but also from the low emission sources.The seasonal variation in sulfate concentration also showed that emission from coal-burning is the key factor to control during the heating season.
基金Supported by the National Nature Science Foundation of China(41175134,41105110,and 41305025)Fundamental Research Funds for Central Universities of China(LZUJBKY-2014-110)China 111 Project(B13045)
文摘Emissions of mineral dust and its mixing with anthropogenic air pollutants affect both regional and global climates. Our fieldwork in late spring 2007(April 25-June 15) measured the physical and optical properties of dust storms mixed with local air pollutants at a rural site about 48 km southeast of central Lanzhou. Levels of air pollutants and aerosol optical properties were observed during the experiment, with concentrations of NOx(6.8 ± 3.3 ppb, average ± standard deviation), CO(694 ± 486 ppb), SO2(6.2 ±10 ppb), O3(50.7 ± 13.1 ppb), and PM10(172 ± 180 μg m-3), and aerosol scattering coefficient(164 ±89 Mm-1; 1 Mm = 106m) and absorption coefficient(11.7 ± 6.6 Mm-1), all much lower than the values observed during air pollution episodes in urban areas. During a major dust storm, the mass concentration of PM10 reached 4072 μg m-3, approximately 21-fold higher than in non-dust storm periods. The mixing ratios of trace gases declined noticeably after a cold front passed through. The observed CO/SO2 and CO/NOx ratios during air pollution episodes were 4.2-18.3 and 13.7-80.5, respectively, compared with the corresponding ratios of 38.1-255.7 and 18.0-245.9 during non-pollution periods. Our investigations suggest that dust storms have a significant influence on air quality in areas far from their source, and this large-scale transport of dust and air pollutants produces major uncertainties in the quantification of the global effects of emissions over Northwest China.
基金provided by the U.S. Environmental Protection Agency (Subcontract Number OR13810-001.04 A10-0223-S001-A04)partly supported by the funding of Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control (No. 2011A060901011)+1 种基金the funding of State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex (No. SCAPC201308)the project of Atmospheric Haze Collaborative Control System Design (No. XDB05030400) from Chinese Academy of Sciences
文摘Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test-Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.
基金supported by the Bilateral Open Partnership Joint Research Projects of the Japan Society for the Promotion of Science, Japan (JPJSBP120219914)the Environment Research and Technology Development Fund (5-1951) of the Environmental Restoration and Conservation Agency of Japan+1 种基金the CHOZEN Project of Kanazawa University, Japanthe cooperative research programs of Institute of Nature and Environmental Technology, Kanazawa University, Japan (21001)。
文摘A three-year sampling campaign was conducted at a roadside air pollution monitoring station in the urban area of Kanazawa, Japan. Due to a new emission regulation, PAHs levels decreased over the sampling campaign, exhibiting values of 706 ± 413 pg/m^(3) in 2017, 559 ±384 pg/m^(3) in 2018, and 473 ± 234 pg/m^(3) in 2019. In each year, similar seasonal variations in PAHs levels were observed, with higher levels observed in winter and lower levels in summer. Among the PAHs isomer ratios, we observed that the ratio of benzo[b]fluoranthene(BbF) and benzo[k]fluoranthene(BkF), [Bb F]/([BbF] + [BkF]), and the ratio of indeno[1,2,3-cd]pyrene(IDP) and benzo[ghi]perylene(BgPe), [IDP]/([BgPe] + [IDP]), showed stability over the sampling campaign and were less affected by the new emission regulation, seasonal variations, and regional characteristics. When using the combined ratio ranges of 0.66-0.80([Bb F]/[BbF] + [BkF]) and 0.26-0.49([IDP]/[Bg Pe] + [IDP]), traffic emissions were clearly distinguished from other PAHs emission sources. Principal component analysis(PCA) and positive matrix factorization(PMF) were also performed to further analyse the characteristics of traffic-related PAHs. Overall, this study affirmed the effectiveness of the new emission regulation in the reduction of PAHs emissions and provided a combined range for identifying PAHs traffic emission sources.
基金supported by the Chinese Key Research and Development Programme(Nos.2018YFC0213301,2017YFC0210101)the National Research Program for Key Issues in Air Pollution Control(No.DQGG0208)+2 种基金the major project of Inner Mongolian Natural Science Foundation(No.2019ZD02)the special contract for science and technology project of Fujian Branch of China Tobacco Corporation(Minyansi Document No.[2014]2 and Minyan Contract No.(2014)185)the Deutsche Forschungsgemeinschaft(DFG,German Research Foundation)-328017493/GRK 2366(Sino-German IRTG AMAIZE-P)。
文摘We investigated variations of PM_(2.5)and water-soluble inorganic ions chemical characteristics at nine urban and rural sites in China using ground-based observations.From 2015 to 2019,mean PM_(2.5)concentration across all sites decreased by 41.9μg/m~3with a decline of 46%at urban sites and 28%at rural sites,where secondary inorganic aerosol(SIAs)contributed to 21%(urban sites)and 17%(rural sites)of the decreased PM_(2.5).SIAs concentrations underwent a decline at urban locations,while sulfate(SO_(4)^(2–)),nitrate(NO_(3)^(–)),and ammonium(NH_(4)^(+))decreased by 49.5%,31.3%and 31.6%,respectively.However,only SO_(4)^(2–)decreased at rural sites,NO_(3)^(–)increased by 21%and NH_(4)^(+)decreased slightly.Those changes contributed to an overall SIAs increase in 2019.Higher molar ratios of NO_(3)^(–)to SO_(4)^(2–)and NH_(4)^(+)to SO_(4)^(2–)were observed at urban sites than rural sites,being highest in the heavily polluted days.Mean molar ratios of NH_(3)/NH_xwere higher in 2019 than 2015 at both urban and rural sites,implying increasing NH_xremained as free NH_(3).Our observations indicated a slower transition from sulfate-driven to nitrate-driven aerosol pollution and less efficient control of NO_(x)than SO_(2)related aerosol formation in rural regions than urban regions.Moreover,the common factor at urban and rural sites appears to be a combination of lower SO_(4)^(2–)levels and an increasing fraction of NO_(3)^(–)to PM_(2.5)under NH_(4)^(+)-rich conditions.Our findings imply that synchronous reduction in NO_(x)and NH_(3)emissions especially rural areas would be effective to mitigate NO_(3)^(–)-driven aerosol pollution.