The research aimed to study absorption and reduction of PM_(2.5)by different plant community structure,and explore which plant community can have better or best comprehensive absorption efficiency,thereby improving an...The research aimed to study absorption and reduction of PM_(2.5)by different plant community structure,and explore which plant community can have better or best comprehensive absorption efficiency,thereby improving and optimizing urban vegetation structure,further promoting improvement of urban air quality,improving people's quality of life,and ensuring a good living environment.In this paper,the method of quadrat survey commonly used in field survey was adopted to record the height,coverage,DBH and other indicators of statistical plants,and corresponding comprehensive value was calculated through these indexes.PM_(2.5)was measured at forest edge,4 and 8 m in the forest,with three repetitions.Subtraction amount of PM_(2.5)determined at different layers was analyzed,as well as its relationship with comprehensive value of community structure.The results showed that PM_(2.5)amount decreased significantly at forest edge,4 and 8 m in the forest,and better community structure had a positive effect on PM_(2.5)absorption.The higher the comprehensive indexes of community structure such as plant height,DBH(arbor),density and coverage,the better the ability of absorbing and reducing PM_(2.5).Therefore,it must pay attention to the diversity of plant species per unit area,to build a good plant community structure,which could better improve structure of local ecosystem,and play a good role in absorbing and reducing PM_(2.5)pollutants in the atmosphere.展开更多
The North China Plain(NCP)is troubled by severe haze pollution and the evolution of haze pollution is closely related to the atmospheric boundary layer(ABL).However,experimental and theoretical studies on the physical...The North China Plain(NCP)is troubled by severe haze pollution and the evolution of haze pollution is closely related to the atmospheric boundary layer(ABL).However,experimental and theoretical studies on the physical-chemical processes of the ABL in the NCP are lacking,with many scientific problems to be addressed.To solve these problems,the Comprehensive Observation on the Atmospheric boundary layer Three-dimensional Structure(COATS)during haze pollution was carried out in the NCP from 2016 to 2020.The COATS experiment adopted a"point-line-surface"spatial layout,obtaining both spatial-temporal profiles of the meteorological and environmental elements in the ABL and the turbulent transport data of fine particulate matter(PM_(2.5))in winter and summer.The research achievements are as follows.The spatial-temporal distribution characteristics of the ABL structure and PM_(2.5)concentrations in NCP were determined.The typical thermal structure of persistent heavy haze events and the pollutant removal mechanism by low-level jets were revealed.It was determined that the spatial structure of the ABL adjusted by the Taihang Mountains is responsible for the heterogeneous distribution of haze pollution in the NCP,and that mountain-induced vertical circulations can promote the formation of elevated pollution layers.The restraints of the atmospheric internal boundaries on horizontal diffusion of pollutants were emphasized.The contribution of the ABL to haze pollution in winter and summer was qualitatively compared and quantitatively estimated.The turbulent transport nature behind the relationship between the atmospheric boundary layer height(ABLH)and surface PM_(2.5)concentrations was analyzed.The concept of"aerosol accumulation layer"was defined,and the applicability of the material method in determining ABLH was clarified.A measurement system for obtaining the turbulent flux of PM_(2.5)concentrations was developed,and the turbulence characteristics of PM_(2.5)concentrations were demonstrated.The COATS experiment is of great theoretical significance for thoroughly understanding the physical mechanisms of the ABL during haze pollution and filling the knowledge gap on the impacts of the ABL three-dimensional structure on haze pollution.The results of this study are conducive to the improvement and development of ABL parameterization schemes and serve as a scientific basis for formulating regional pollution prevention and control measures.展开更多
In this paper, the characteristics of the atmospheric boundary layer(ABL) vertical structure over the North China Plain(NCP) during a comprehensive observation experiment conducted during 15–21 December 2018 were inv...In this paper, the characteristics of the atmospheric boundary layer(ABL) vertical structure over the North China Plain(NCP) during a comprehensive observation experiment conducted during 15–21 December 2018 were investigated. Observational data were obtained with a large tethered balloon, Doppler wind lidar, and ground-level instruments. The maximum concentration of PM_(2.5) exceeded 200 μg m^(-3), and the ratio of PM_(2.5)/PM_(10) was approximately 0.4(its maxi-mum was approximately 0.8) during the whole observation period, indicating the explosive growth of dominant fine-mode aerosols in the winter heating season. Elevated concentrations of pollutants decreased the solar irradiance received by the ground, resulting in lower temperature at ground level. Our results illustrate three distinct types of vertical profiles: Type 1(convective state)—the concentration of PM_(2.5) decreased nearly linearly with increase of the height below approximately 600 m;Type 2(stable state)—the PM_(2.5) concentration sharply decreased from the ground to approximately 200 m;and Type 3(multilayer structure)—some pollutants were suspended aloft in the upper air layer. Diurnal evolution of the vertical profiles of PM_(2.5) and their relationship with the changes in meteorological factors were identified. From daytime to nighttime, the vertical profiles evolved from Type 1 to Type 2 or Type 3. All the 33 vertical PM_(2.5) profiles that we obtained showed a strong relationship with elements of the ABL structure, such as the distributions of winds, the inversion layer, and turbulence activities. A light-wind layer and weak turbulence activity, especially within the inversion layer, contributed greatly to the accumulation of pollutants.Vertical PM_(2.5) concentration patterns were also greatly affected by local ground-level emission sources and regional transport processes.展开更多
In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter（PM_（2.5）） can cause cogn...In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter（PM_（2.5）） can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM_（2.5） inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM_（2.5） ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM_（2.5） inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.展开更多
基金Supported by the Project of Shenzhen Science and Technology Innovation Committee(JCYJ20150831190958804)the Project of Shenzhen Human Settlements Committee(B41620320).
文摘The research aimed to study absorption and reduction of PM_(2.5)by different plant community structure,and explore which plant community can have better or best comprehensive absorption efficiency,thereby improving and optimizing urban vegetation structure,further promoting improvement of urban air quality,improving people's quality of life,and ensuring a good living environment.In this paper,the method of quadrat survey commonly used in field survey was adopted to record the height,coverage,DBH and other indicators of statistical plants,and corresponding comprehensive value was calculated through these indexes.PM_(2.5)was measured at forest edge,4 and 8 m in the forest,with three repetitions.Subtraction amount of PM_(2.5)determined at different layers was analyzed,as well as its relationship with comprehensive value of community structure.The results showed that PM_(2.5)amount decreased significantly at forest edge,4 and 8 m in the forest,and better community structure had a positive effect on PM_(2.5)absorption.The higher the comprehensive indexes of community structure such as plant height,DBH(arbor),density and coverage,the better the ability of absorbing and reducing PM_(2.5).Therefore,it must pay attention to the diversity of plant species per unit area,to build a good plant community structure,which could better improve structure of local ecosystem,and play a good role in absorbing and reducing PM_(2.5)pollutants in the atmosphere.
基金supported by the National Natural Science Foundation of China(Grant Nos.42090031,42175092,92044301&91544216)the National Key R&D Program of China(Grant Nos.2016YFC0203306&2017YFC0209600)the National Research Program for Key Issues in Air Pollution Control(Grant Nos.DQGG0104&DQGG0106)。
文摘The North China Plain(NCP)is troubled by severe haze pollution and the evolution of haze pollution is closely related to the atmospheric boundary layer(ABL).However,experimental and theoretical studies on the physical-chemical processes of the ABL in the NCP are lacking,with many scientific problems to be addressed.To solve these problems,the Comprehensive Observation on the Atmospheric boundary layer Three-dimensional Structure(COATS)during haze pollution was carried out in the NCP from 2016 to 2020.The COATS experiment adopted a"point-line-surface"spatial layout,obtaining both spatial-temporal profiles of the meteorological and environmental elements in the ABL and the turbulent transport data of fine particulate matter(PM_(2.5))in winter and summer.The research achievements are as follows.The spatial-temporal distribution characteristics of the ABL structure and PM_(2.5)concentrations in NCP were determined.The typical thermal structure of persistent heavy haze events and the pollutant removal mechanism by low-level jets were revealed.It was determined that the spatial structure of the ABL adjusted by the Taihang Mountains is responsible for the heterogeneous distribution of haze pollution in the NCP,and that mountain-induced vertical circulations can promote the formation of elevated pollution layers.The restraints of the atmospheric internal boundaries on horizontal diffusion of pollutants were emphasized.The contribution of the ABL to haze pollution in winter and summer was qualitatively compared and quantitatively estimated.The turbulent transport nature behind the relationship between the atmospheric boundary layer height(ABLH)and surface PM_(2.5)concentrations was analyzed.The concept of"aerosol accumulation layer"was defined,and the applicability of the material method in determining ABLH was clarified.A measurement system for obtaining the turbulent flux of PM_(2.5)concentrations was developed,and the turbulence characteristics of PM_(2.5)concentrations were demonstrated.The COATS experiment is of great theoretical significance for thoroughly understanding the physical mechanisms of the ABL during haze pollution and filling the knowledge gap on the impacts of the ABL three-dimensional structure on haze pollution.The results of this study are conducive to the improvement and development of ABL parameterization schemes and serve as a scientific basis for formulating regional pollution prevention and control measures.
基金Supported by the National Key Research and Development Program of China (2017YFC0209605)National Natural Science Foundation of China (41975108)General Financial Grant from the China Postdoctoral Science Foundation (2020M670420)。
文摘In this paper, the characteristics of the atmospheric boundary layer(ABL) vertical structure over the North China Plain(NCP) during a comprehensive observation experiment conducted during 15–21 December 2018 were investigated. Observational data were obtained with a large tethered balloon, Doppler wind lidar, and ground-level instruments. The maximum concentration of PM_(2.5) exceeded 200 μg m^(-3), and the ratio of PM_(2.5)/PM_(10) was approximately 0.4(its maxi-mum was approximately 0.8) during the whole observation period, indicating the explosive growth of dominant fine-mode aerosols in the winter heating season. Elevated concentrations of pollutants decreased the solar irradiance received by the ground, resulting in lower temperature at ground level. Our results illustrate three distinct types of vertical profiles: Type 1(convective state)—the concentration of PM_(2.5) decreased nearly linearly with increase of the height below approximately 600 m;Type 2(stable state)—the PM_(2.5) concentration sharply decreased from the ground to approximately 200 m;and Type 3(multilayer structure)—some pollutants were suspended aloft in the upper air layer. Diurnal evolution of the vertical profiles of PM_(2.5) and their relationship with the changes in meteorological factors were identified. From daytime to nighttime, the vertical profiles evolved from Type 1 to Type 2 or Type 3. All the 33 vertical PM_(2.5) profiles that we obtained showed a strong relationship with elements of the ABL structure, such as the distributions of winds, the inversion layer, and turbulence activities. A light-wind layer and weak turbulence activity, especially within the inversion layer, contributed greatly to the accumulation of pollutants.Vertical PM_(2.5) concentration patterns were also greatly affected by local ground-level emission sources and regional transport processes.
基金supported by the National Science Foundation of China(Nos.21377076,91543203,21477070,21222701)Specialized Research Fund for the Doctoral Program of Higher Education of China(Nos.20121401110003,20131401110005)+1 种基金Project Supported by Shanxi Young Sanjin Scholarship of China,Program for the Outstanding Innovative Teams of Higher Learning Institutions of ShanxiResearch Project Supported by Shanxi Scholarship Council of China(No.2015-006)
文摘In light of the accelerated aging of the global population and the deterioration of the atmosphere pollution, we sought to clarify the potential mechanisms by which fine particulate matter（PM_（2.5）） can cause cognitive impairment and neurodegeneration through the alteration of mitochondrial structure and function. The results indicate that PM_（2.5） inhalation reduces ATP production by disrupting the aerobic tricarboxylic acid cycle and oxidative phosphorylation, thereby causing the hypophosphorylation of tau in the cortices of middle-aged mice. Furthermore, excessive reactive oxygen species generation was involved in the impairment. Interestingly, these alterations were partially reversed after exposure to PM_（2.5） ended. These findings clarify the mechanism involved in mitochondrial abnormality-related neuropathological dysfunction in response to atmospheric PM_（2.5） inhalation and provide an optimistic sight for alleviating the adverse health outcomes in polluted areas.
