Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SW...Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.展开更多
The Ili River is a typical transboundary river between China and Kazakhstan,with glaciers within its basin serving as a crucial solid water resource.Recently,we compiled the Chinese Glacier Inventory of Xinjiang in 20...The Ili River is a typical transboundary river between China and Kazakhstan,with glaciers within its basin serving as a crucial solid water resource.Recently,we compiled the Chinese Glacier Inventory of Xinjiang in 2020(CGI-XJ2020)using high-resolution satellite imagery(<2 m),based on visual interpretation.This study presented the state of glaciers in the Ili River Basin in 2020 by utilizing the data from CGI-XJ2020.It quantified glacier changes in 1960s–2020 based on CGI-XJ2020 and revised datasets from the First and Second Chinese Glacier Inventories.The results indicated that in 2020,the Ili River Basin contained 2,177 glaciers,totaling 1,433.19 km^(2)in area.Among them,213 glaciers were covered by 57.43 km^(2)of debris.The total uncertainty in glacier area was 46.43 km^(2),accounting for approximately 3.2%of the total area.Mapped glacier areas varied from 0.003 to 74.67 km^(2),with an average area of 0.66 km^(2)and a median area of 0.15 km^(2).Glaciers<0.5 km^(2)in size dominated in numbers,accounting for 75.1%of the total.Glaciers in the basin have undergone significant retreat during 1960s–2020,with their total area decreasing by 589.38 km^(2)(29.15%).A total of 495 glaciers(with an area of 49.67 km^(2))disappeared.The average annual glacier area retreat rates for 1960s-2007 and 2007–2020 were 10.86 km^(2)/a(0.54%/a)and 9.41 km^(2)/a(0.61%/a),respectively,showing a continued acceleration in glacier shrinkage,despite a slight decrease in absolute retreat rates.展开更多
[Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili r...[Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili region.[Methods] The pixel dichotomy model was used to process the MODIS data and analyze the change of vegetation coverage in the Ili River Basin from 2006 to 2020.[Results] (i)The vegetation coverage in the Ili River Basin increases gradually from west to east,and fluctuates greatly between years.(ii)By monitoring the change rate of the maximum vegetation coverage,it is found that the vegetation coverage of the basin has experienced a process of first decline and then recovery in the past 15 years.(iii)In spatial distribution,vegetation coverage has improved in some regions,while it has deteriorated in others,which may be related to regional climate change and human activities.[Conclusions] The vegetation coverage in the Ili River Basin showed significant spatial and temporal differences during the study period,and its changes were affected by both natural and human factors.展开更多
基金supported by the National Key R&D Program of China(No.2017YFC0212501)the Fundamental Research Funds for the Central Universities(No.2021YJSMT09)the research project on deep source apportionment of urban air pollution and pollution control strategies in the core area of the Ili River Valley。
文摘Polycyclic Aromatic Hydrocarbons(PAHs),along with their derivatives nitro-PAHs and oxy-PAHs,are globally recognized toxic pollutants.This research conducted daily PM_(2.5)sampling in winter 2021 at three urban(YNCE,SWP,and NG)and three suburban sites(HC,CTV,and YNE)in the Ili River Valley(IRV).For the first time in the IRV,a comprehensive study on 39 PAHs and derivatives was carried out.The results showed that the average∑_(16)PAHs concentration was 130.21±98.94 ng/m^(3),with 16PAHs constituting the dominant fraction(112.51±86.48 ng/m^(3)).The mean BaP and the total BaP equivalent quotient(TEQ)concentrations were 10.28±8.85 ng/m^(3)and 19.74±16.70 ng/m^(3),respectively.Approximately 88%of the daily BaP averages and 98%of the daily TEQ averages exceeded the national daily average standard of BaP(2.5 ng/m^(3)),indicating severe local BaP pollution.Urban sites had notably higher∑PAHs and TEQ concentrations than suburban sites,attributed to increased vehicular traffic and coal combustion in urban areas.PMF results showed that traffic emissions(32.7%-60.5%),coal combustion(13.9%-24.3%)and secondary formation(14.7%-22.7%)were the primary contributors to∑PAHs.Urban sites experienced a greater influence from traffic,while suburban sites were more impacted by coal and biomass burning.On polluted days,traffic sources’contributions increased significantly at HC,YNE,NG and YNCE sites,and secondary formation sources’contributions grew at CTV and YNCE sites.The sourcedependent BaPeq results underscored the role of secondary-formed PAH derivatives in TEQ.
基金supported by Third Xinjiang Scientific Expedition Program(Grant No.2022xjkk0101)Second Qinghai-Tibet Scientific Expedition Program(Grant No.2019 QZKK0201)+2 种基金Third Xinjiang Sci-entific Expedition Program(Grant No.2021xjkk0401)National Natural Science Foundation of China(Grant No.42301166)National Natural Science Foundation of China(Grant No.42371148)。
文摘The Ili River is a typical transboundary river between China and Kazakhstan,with glaciers within its basin serving as a crucial solid water resource.Recently,we compiled the Chinese Glacier Inventory of Xinjiang in 2020(CGI-XJ2020)using high-resolution satellite imagery(<2 m),based on visual interpretation.This study presented the state of glaciers in the Ili River Basin in 2020 by utilizing the data from CGI-XJ2020.It quantified glacier changes in 1960s–2020 based on CGI-XJ2020 and revised datasets from the First and Second Chinese Glacier Inventories.The results indicated that in 2020,the Ili River Basin contained 2,177 glaciers,totaling 1,433.19 km^(2)in area.Among them,213 glaciers were covered by 57.43 km^(2)of debris.The total uncertainty in glacier area was 46.43 km^(2),accounting for approximately 3.2%of the total area.Mapped glacier areas varied from 0.003 to 74.67 km^(2),with an average area of 0.66 km^(2)and a median area of 0.15 km^(2).Glaciers<0.5 km^(2)in size dominated in numbers,accounting for 75.1%of the total.Glaciers in the basin have undergone significant retreat during 1960s–2020,with their total area decreasing by 589.38 km^(2)(29.15%).A total of 495 glaciers(with an area of 49.67 km^(2))disappeared.The average annual glacier area retreat rates for 1960s-2007 and 2007–2020 were 10.86 km^(2)/a(0.54%/a)and 9.41 km^(2)/a(0.61%/a),respectively,showing a continued acceleration in glacier shrinkage,despite a slight decrease in absolute retreat rates.
基金General Program of Natural Science Foundation of Xinjiang Uygur Autonomous Region(2022D01A275)Project of Inner Mongolia M-Grass Ecology and Environment(Group)Co.,Ltd.(2022-NFGA-004).
文摘[Objectives] To analyze the dynamic changes of maximum vegetation coverage in Ili River Basin from 2006 to 2020,and to explore the vegetation change and its influencing factors in the forest-grassland ecotone of Ili region.[Methods] The pixel dichotomy model was used to process the MODIS data and analyze the change of vegetation coverage in the Ili River Basin from 2006 to 2020.[Results] (i)The vegetation coverage in the Ili River Basin increases gradually from west to east,and fluctuates greatly between years.(ii)By monitoring the change rate of the maximum vegetation coverage,it is found that the vegetation coverage of the basin has experienced a process of first decline and then recovery in the past 15 years.(iii)In spatial distribution,vegetation coverage has improved in some regions,while it has deteriorated in others,which may be related to regional climate change and human activities.[Conclusions] The vegetation coverage in the Ili River Basin showed significant spatial and temporal differences during the study period,and its changes were affected by both natural and human factors.
