In the autumn of 2008, the vertical profiles of ozone and meteorological parameters in the low troposphere （0-1000 m） were observed at two sites around Beijing, specifically urban Nanjiao and rural Shangdianzi. At n...In the autumn of 2008, the vertical profiles of ozone and meteorological parameters in the low troposphere （0-1000 m） were observed at two sites around Beijing, specifically urban Nanjiao and rural Shangdianzi. At night and early morning, the lower troposphere divided into two stratified layers due to temperature inversion. Ozone in the lower layer showed a large gradient due to the titration of NO. Air flow from the southwest brought ozone-rich air to Beijing, and the ozone profiles were marked by a continuous increase in the residual layer at night. The accumulated ozone in the upper layer played an important role in the next day＇s surface peak ozone concentration, and caused a rapid increase in surface ozone in the morning. Wind direction shear and wind speed shear exhibited different influences on ozone profiles and resulted in different surface ozone concentrations in Beijing.展开更多
The sensitivity of Chinese soybean cultivars to ambient ozone（O3） in the field is unknown,although soybean is a major staple food in China. Using ethylenediurea（EDU） as an O3 protectant, we tested the gas exchange...The sensitivity of Chinese soybean cultivars to ambient ozone（O3） in the field is unknown,although soybean is a major staple food in China. Using ethylenediurea（EDU） as an O3 protectant, we tested the gas exchange, pigments, antioxidants and biomass of 19 cultivars exposed to 28 ppm·hr AOT40（accumulated O3 over an hourly concentration threshold of40 ppb） over the growing season at a field site in China. By comparing the average biomass with and without EDU, we estimated the cultivar-specific sensitivity to O3 and ranked the cultivars from very tolerant（〈 10% change） to highly sensitive（〉 45% change）, which helps in choosing the best-suited cultivars for local cultivation. Higher lipid peroxidation and activity of the ascorbate peroxidase enzyme were major responses to O3 damage, which eventually translated into lower biomass production. The constitutional level of total ascorbate in the leaves was the most important parameter explaining O3 sensitivity among these cultivars. Surprisingly, the role of stomatal conductance was insignificant. These results will guide future breeding efforts towards more O3-tolerant cultivars in China, while strategies for implementing control measures of regional O3 pollution are being implemented. Overall, these results suggest that present ambient O3 pollution is a serious concern for soybean in China, which highlights the urgent need for policy-making actions to protect this critical staple food.展开更多
To investigate the characteristics of ground level ozone(O3)for Henan Province,the ambient air quality monitoring data of 2015 and 2016 were analyzed.The result showed that the 8 h-max-O3 concentrations displayed a di...To investigate the characteristics of ground level ozone(O3)for Henan Province,the ambient air quality monitoring data of 2015 and 2016 were analyzed.The result showed that the 8 h-max-O3 concentrations displayed a distinct seasonality,where the maximum and minimum values,averaging 140.41,54.19μg/m3,occurred in summer and winter,respectively.There is a significant correlation between meteorological factors and O3 concentration.The Voronoi neighborhood averaging analysis indic ated that O3,temperature,and ultraviolet radiation in Henan province were decreased from northwest to southeast,while relative humidity and precipitation displayed the opposite trend.Besides meteorological factors,the chemical processes play an essential role in ozone formation.Reactions of NO,NO2 and O3 form a closed system,and the partitioning point of the OX-component(O3+NO2)was at 40 and 80μg/m3 for nitrogen oxide(NOx)in winter and summer,respectively,with NO2 dominating at higher NOx pollution and O3 being the m ajor component at lower levels.The relationship between oxidant(OX=O3+NO2)and NOx concentrations were evaluated to understand the regional and local contribution of OX.It showed that high regional contribution occurred in the spring,whereas the highest local contribution lead to the summer peak of O3 observed in Zhengzhou.This present study reveals important environment impacts from the photochemical process and the meteorological conditions in the region with better understanding on the O3 characterization.展开更多
Ethylenediurea(EDU)has been used as a chemical protectant against ozone(O3).However,its protective effect and physiological mechanisms are still uncertain.The present study aimed to investigate the changes of foliar v...Ethylenediurea(EDU)has been used as a chemical protectant against ozone(O3).However,its protective effect and physiological mechanisms are still uncertain.The present study aimed to investigate the changes of foliar visible injury,physiological characteristics and emission rates of volatile organic compounds(VOCs)in one-year-old Populus alba"Berolinensis"saplings pretreated with EDU and exposed to elevated O3(EO,120μg/m3).The results showed that foliar visible injury symptoms under EO were significantly alleviated in plants with EDU application(p<0.05).Under EO,net photosynthetic rate,the maximum photochemical efficiency of PSII and the photochemical efficiency of PSII of plants pretreated with 300 and600 mg/L EDU were similar to unexposed controls and significantly higher compared to EOstressed plants without EDU pretreatment,respectively.Malondialdehyde content was highest in EO without EDU and decreased significantly by 14.9%and 21.3%with 300 and600 mg/L EDU pretreatment,respectively.EDU pretreatment alone increased superoxide dismutase activity by 10-fold in unexposed plants with further increases of 88.4%and 37.5%in EO plants pretreated with 300 and 600 mg/L EDU pretreatment,respectively(p<0.05).Abscisic acid content declined under EO relative to unexposed controls with the effect partially reversed by EDU pretreatments.Similarly,VOCs emission rate declined under EO relative to unexposed plants with a recovery of emission rate observed with 300 and 600 mg/L EDU pretreatment.These findings provided significant evidence that EDU exerted a beneficial effect and protection on the tested plants against O3 stress.展开更多
Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a c...Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a cost-effective basis. This paper identi-fies and assesses a range of options for addressing this problem. We apply the Ambient Least Cost Model and compare the eco-nomic costs of control options, then recommend the most effective sequence to realize pollution control at the lowest cost. The study finds that installing of Stage II gasoline vapor recovery system at Beijing's 1446 gasoline stations would be the most cost-effective option. Overall, options to reduce ozone pollution by cutting ve-hicular emissions are much more cost-effective than options to "clean up" coal-fired power plants.展开更多
A modified Gauss-Markov model with weighted constraints was constructed by combining satellite altimeter and tide gauge records. Vertical motion rates of nine tide gauge stations around the Bohal Sea and Yellow Sea ar...A modified Gauss-Markov model with weighted constraints was constructed by combining satellite altimeter and tide gauge records. Vertical motion rates of nine tide gauge stations around the Bohal Sea and Yellow Sea are estimated. This is the first time systematic estimates have been derived in this region. Downward trends were seen at the six tide gauge stations located at Tanggu, Longkou, Laohutan, Bayuquan, Xiaochangshan, and Yantai; with vertical motion rates of-1.82±0.50, -1.65±0.46, -0.88±0.42, -0.58±0.62, -0.13±0.43, and -0.01±0.43 mm/yr, respectively. Upward trends were seen at the three tide gauge stations located at Qinhuangdao, Huludao and Chengshantou; with vertical motion rates of 1.12±0.46, 0.55±0.49 and 0.26±0.44 mm/yr, respectively. There was significant subsidence in Tanggu and Longkou, and a rising trend in Qinhuangdao. According to our results, the rate of sea level rise calculated from these tide gauge records can be improved using a more accurate measurement of the land elevation accounting for lifting or subsidence. The model derived can be used to estimate vertical motions of tide gauge stations, and can be widely applied to revise the benchmark levels of tide gauges.展开更多
As in many parts of the world, long-term excessive extraction of groundwater has caused significant land-surface sub- sidence in the residential areas of Datun coal mining district in East China. The recorded maximum ...As in many parts of the world, long-term excessive extraction of groundwater has caused significant land-surface sub- sidence in the residential areas of Datun coal mining district in East China. The recorded maximum level of subsidence in the area since 1976 to 2006 is 863 mm, and the area with an accumulative subsidence more than 200 mm has reached 33.1 km2 by the end of 2006. Over ten cases of building crack due to ground subsidence have already been observed. Spatial variation in ground subsi- dence often leads to a corresponding pattern of ground deformation. Buildings and underground infrastructures have been under a higher risk of damage in locations with greater differential ground deformation. Governmental guideline in China classifies build- ing damages into four different levels, based on the observable measures such as the width of wall crack, the degree of door and window deformation, the degree of wall inclination and the degree of structural destruction. Building damage level (BDL) is esti- mated by means of ground deformation analysis in terms of variations in slope gradient and curvature. Ground deformation analysis in terms of variations in slope gradient has shown that the areas of BDL III and BDL II sites account for about 0.013 km2 and 0.284 km2 respectively in 2006, and the predicted areas of BDL (define this first) III and II sites will be about 0.029 km2 and 0.423 km2 respectively by 2010. The situation is getting worse as subsidence continues. That calls for effective strategies for subsidence miti- gation and damage reduction, in terms of sustainable groundwater extraction, enhanced monitoring and the establishment of early warning systems.展开更多
基金supported by the Beijing Natural Science Foundation (No. 8082012,8092010)the Special Fund for Meteorological Research in the Public Interest (No. GYHY200806027)
文摘In the autumn of 2008, the vertical profiles of ozone and meteorological parameters in the low troposphere （0-1000 m） were observed at two sites around Beijing, specifically urban Nanjiao and rural Shangdianzi. At night and early morning, the lower troposphere divided into two stratified layers due to temperature inversion. Ozone in the lower layer showed a large gradient due to the titration of NO. Air flow from the southwest brought ozone-rich air to Beijing, and the ozone profiles were marked by a continuous increase in the residual layer at night. The accumulated ozone in the upper layer played an important role in the next day＇s surface peak ozone concentration, and caused a rapid increase in surface ozone in the morning. Wind direction shear and wind speed shear exhibited different influences on ozone profiles and resulted in different surface ozone concentrations in Beijing.
基金supported by State Key Laboratory of Soil and Sustainable Agriculture(No.Y20160030)the Hundred Talents Program,Chinese Academy of Sciences,Chinese Academy of Sciences President's International Fellowship Initiative(PIFI)for Senior Scientists(Grant Number 2016VBA057)CNR-CAS bilateral agreement 2017–2019(Ozone impacts on plant ecosystems in China and Italy)
文摘The sensitivity of Chinese soybean cultivars to ambient ozone（O3） in the field is unknown,although soybean is a major staple food in China. Using ethylenediurea（EDU） as an O3 protectant, we tested the gas exchange, pigments, antioxidants and biomass of 19 cultivars exposed to 28 ppm·hr AOT40（accumulated O3 over an hourly concentration threshold of40 ppb） over the growing season at a field site in China. By comparing the average biomass with and without EDU, we estimated the cultivar-specific sensitivity to O3 and ranked the cultivars from very tolerant（〈 10% change） to highly sensitive（〉 45% change）, which helps in choosing the best-suited cultivars for local cultivation. Higher lipid peroxidation and activity of the ascorbate peroxidase enzyme were major responses to O3 damage, which eventually translated into lower biomass production. The constitutional level of total ascorbate in the leaves was the most important parameter explaining O3 sensitivity among these cultivars. Surprisingly, the role of stomatal conductance was insignificant. These results will guide future breeding efforts towards more O3-tolerant cultivars in China, while strategies for implementing control measures of regional O3 pollution are being implemented. Overall, these results suggest that present ambient O3 pollution is a serious concern for soybean in China, which highlights the urgent need for policy-making actions to protect this critical staple food.
基金supported by the National Key Research and Development Program of China(No.2017YFC0212403)
文摘To investigate the characteristics of ground level ozone(O3)for Henan Province,the ambient air quality monitoring data of 2015 and 2016 were analyzed.The result showed that the 8 h-max-O3 concentrations displayed a distinct seasonality,where the maximum and minimum values,averaging 140.41,54.19μg/m3,occurred in summer and winter,respectively.There is a significant correlation between meteorological factors and O3 concentration.The Voronoi neighborhood averaging analysis indic ated that O3,temperature,and ultraviolet radiation in Henan province were decreased from northwest to southeast,while relative humidity and precipitation displayed the opposite trend.Besides meteorological factors,the chemical processes play an essential role in ozone formation.Reactions of NO,NO2 and O3 form a closed system,and the partitioning point of the OX-component(O3+NO2)was at 40 and 80μg/m3 for nitrogen oxide(NOx)in winter and summer,respectively,with NO2 dominating at higher NOx pollution and O3 being the m ajor component at lower levels.The relationship between oxidant(OX=O3+NO2)and NOx concentrations were evaluated to understand the regional and local contribution of OX.It showed that high regional contribution occurred in the spring,whereas the highest local contribution lead to the summer peak of O3 observed in Zhengzhou.This present study reveals important environment impacts from the photochemical process and the meteorological conditions in the region with better understanding on the O3 characterization.
基金supported by the National Natural Science Foundation of China (Nos. 41675153, 31870458, 31270518, 31170573, 31670412)
文摘Ethylenediurea(EDU)has been used as a chemical protectant against ozone(O3).However,its protective effect and physiological mechanisms are still uncertain.The present study aimed to investigate the changes of foliar visible injury,physiological characteristics and emission rates of volatile organic compounds(VOCs)in one-year-old Populus alba"Berolinensis"saplings pretreated with EDU and exposed to elevated O3(EO,120μg/m3).The results showed that foliar visible injury symptoms under EO were significantly alleviated in plants with EDU application(p<0.05).Under EO,net photosynthetic rate,the maximum photochemical efficiency of PSII and the photochemical efficiency of PSII of plants pretreated with 300 and600 mg/L EDU were similar to unexposed controls and significantly higher compared to EOstressed plants without EDU pretreatment,respectively.Malondialdehyde content was highest in EO without EDU and decreased significantly by 14.9%and 21.3%with 300 and600 mg/L EDU pretreatment,respectively.EDU pretreatment alone increased superoxide dismutase activity by 10-fold in unexposed plants with further increases of 88.4%and 37.5%in EO plants pretreated with 300 and 600 mg/L EDU pretreatment,respectively(p<0.05).Abscisic acid content declined under EO relative to unexposed controls with the effect partially reversed by EDU pretreatments.Similarly,VOCs emission rate declined under EO relative to unexposed plants with a recovery of emission rate observed with 300 and 600 mg/L EDU pretreatment.These findings provided significant evidence that EDU exerted a beneficial effect and protection on the tested plants against O3 stress.
基金supported by the Economyand Environment Program for Southeast Asia (EEPSEA)Beijing Science and Technology Commission (GrantNo.D09040903670905)+1 种基金Study on the Regional Air PollutionControl Strategy and PolicyShanghai Tongji Gao Tingyao Environmental Science and Technology Development Foundation
文摘Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a cost-effective basis. This paper identi-fies and assesses a range of options for addressing this problem. We apply the Ambient Least Cost Model and compare the eco-nomic costs of control options, then recommend the most effective sequence to realize pollution control at the lowest cost. The study finds that installing of Stage II gasoline vapor recovery system at Beijing's 1446 gasoline stations would be the most cost-effective option. Overall, options to reduce ozone pollution by cutting ve-hicular emissions are much more cost-effective than options to "clean up" coal-fired power plants.
基金supported by the National Natural Science Foundation of China(Grant Nos.4140603241206021&41376014)+4 种基金the National Basic Research Program of China(Grant No.2012CB955601)the National Key Technology R&D Program of China(Grant No.2014BAB12B02)the Key Technology R&D Program of Tianjin(Grant No.14ZCZDSF00012)the Open Fund of the State Key Laboratory of Satellite Ocean Environment Dynamics at the Second Institute of OceanographySOA(Grant No.SOED1305)
文摘A modified Gauss-Markov model with weighted constraints was constructed by combining satellite altimeter and tide gauge records. Vertical motion rates of nine tide gauge stations around the Bohal Sea and Yellow Sea are estimated. This is the first time systematic estimates have been derived in this region. Downward trends were seen at the six tide gauge stations located at Tanggu, Longkou, Laohutan, Bayuquan, Xiaochangshan, and Yantai; with vertical motion rates of-1.82±0.50, -1.65±0.46, -0.88±0.42, -0.58±0.62, -0.13±0.43, and -0.01±0.43 mm/yr, respectively. Upward trends were seen at the three tide gauge stations located at Qinhuangdao, Huludao and Chengshantou; with vertical motion rates of 1.12±0.46, 0.55±0.49 and 0.26±0.44 mm/yr, respectively. There was significant subsidence in Tanggu and Longkou, and a rising trend in Qinhuangdao. According to our results, the rate of sea level rise calculated from these tide gauge records can be improved using a more accurate measurement of the land elevation accounting for lifting or subsidence. The model derived can be used to estimate vertical motions of tide gauge stations, and can be widely applied to revise the benchmark levels of tide gauges.
文摘As in many parts of the world, long-term excessive extraction of groundwater has caused significant land-surface sub- sidence in the residential areas of Datun coal mining district in East China. The recorded maximum level of subsidence in the area since 1976 to 2006 is 863 mm, and the area with an accumulative subsidence more than 200 mm has reached 33.1 km2 by the end of 2006. Over ten cases of building crack due to ground subsidence have already been observed. Spatial variation in ground subsi- dence often leads to a corresponding pattern of ground deformation. Buildings and underground infrastructures have been under a higher risk of damage in locations with greater differential ground deformation. Governmental guideline in China classifies build- ing damages into four different levels, based on the observable measures such as the width of wall crack, the degree of door and window deformation, the degree of wall inclination and the degree of structural destruction. Building damage level (BDL) is esti- mated by means of ground deformation analysis in terms of variations in slope gradient and curvature. Ground deformation analysis in terms of variations in slope gradient has shown that the areas of BDL III and BDL II sites account for about 0.013 km2 and 0.284 km2 respectively in 2006, and the predicted areas of BDL (define this first) III and II sites will be about 0.029 km2 and 0.423 km2 respectively by 2010. The situation is getting worse as subsidence continues. That calls for effective strategies for subsidence miti- gation and damage reduction, in terms of sustainable groundwater extraction, enhanced monitoring and the establishment of early warning systems.
