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1.
GIS-based proximity models are one of the key tools for the assessment of exposure to air pollution when the density of spatial monitoring stations is sparse. Central to exposure assessment that utilizes proximity models is the ‘exposure intensity–distance’ hypothesis. A major weakness in the application of this hypothesis is that it does not account for the Gaussian processes that are at the core of the physical mechanisms inherent in the dispersion of air pollutants.

Building upon the utility of spatial proximity models and the theoretical reliability of Gaussian dispersion processes of air pollutants, this study puts forward a novel Gaussian weighting function-aided proximity model (GWFPM). The study area and data set for this work consisted of transport-related emission sources of PM2.5 in the Houston-Baytown-Sugar Land metropolitan area. Performance of the GWFPM was validated by comparing on-site observed PM2.5 concentrations with results from classical ordinary kriging (OK) interpolation and a robust emission-weighted proximity model (EWPM). Results show that the fitting R2 between possible exposure intensity calculated by GWFPM and observed PM2.5 concentrations was 0.67. A variety of statistical evidence (i.e., bias, root mean square error [RMSE], mean absolute error [MAE], and correlation coefficient) confirmed that GWFPM outperformed OK and EWPM in estimating annual PM2.5 concentrations for all monitoring sites. These results indicate that a GWFPM utilizing the physical dispersing mechanisms integrated may more effectively characterize annual-scale exposure than traditional models. Using GWFPM, receptors’ exposure to air pollution can be assessed with sufficient accuracy, even in those areas with a low density of monitoring sites. These results may be of use to public health and planning officials in a more accurate assessment of the annual exposure risk to a population, especially in areas where monitoring sites are sparse.  相似文献   


2.
ABSTRACT

This paper discusses characteristics of the seasonal variation in phthalate acid esters (PAEs) in the PM2.5 in the city of Changji, which is located an arid area of Xinjiang Province, northwest China. Samples were collected using a Laoying 2030 median discharge intelligent total suspended particulate (TSP) sampler and analyzed by a Shimadzu GC-2010 gas chromatograph. The results showed that PAEs in PM2.5 were mainly composed of phthalic acid dibutyl phthalate (DBP) and phthalic acid (2-)ethyl hexyl ester (DEHP). DBP and DEHP are the most commonly used plasticizers, accounting for the majority of plasticizers used, and have large environmental emissions. Compared with the proportions of TSPs, proportions of DBP and DEHP in the PM2.5 were lower, while the proportions of DMP and DEP were higher. A correlation exists between the distribution of PAEs and the particle size and concentration of atmospheric particulates. Seasonal variations in DBP and DEHP were the same, with lowest concentrations in the summer. Although seasonal variation in DMP was not the same as those of DBP and DEHP, the general trend was similar. Seasonal variation in DEP was different from those of other PAEs. This pattern is related to PAE characteristics and seasonal variations in their sources.  相似文献   

3.
Haze pollution has become a severe environmental problem in the daily life of the people in China. PM2.5 makes a significant contribution to poor air quality. The spatio-temporal features of China’s PM2.5 concentrations should be investigated. This paper, based on observed data from 945 newly located monitoring sites in 2014 and industrial working population data obtained from International Standard Industrial Classification (ISIC), reveals the spatio-temporal variations of PM2.5 concentrations in China and the correlations among different industries. We tested the spatial autocorrelation of PM2.5 concentrations in the cities of China with the spatial autocorrelation model. A correlation coefficient to examine the correlativity of PM2.5 concentrations and 23 characteristic variables for 190 cities in China in 2014, from which the most important ones were chosen, and then a regression model was built to further reveal the social and economic factors affecting PM2.5 concentrations. Results: (1) The Hu Huanyong Line and the Yangtze River were the E-W divide and S-N divide between high and low values of China. (2) The PM2.5 concentrations shows great seasonal variation, which is high in autumn and winter but low in spring and summer. The monthly average shows a U-shaped pattern, and daily average presents a periodic and impulse-shaped change. (3) PM2.5 concentrations had a distinct characteristic of spatial agglomeration. The North China Plain was the predominant region of agglomeration, and the southeastern coastal area had stable good air quality.  相似文献   

4.
ABSTRACT

One of the major challenges in conducting epidemiological studies of air pollution and health is the difficulty of estimating the degree of exposure accurately. Fine particulate matter (PM2.5) concentrations vary in space and time, which are difficult to estimate in rural, suburban and smaller urban areas due to the sparsity of the ground monitoring network. Satellite retrieved aerosol optical depth (AOD) has been increasingly used as a proxy of ground PM2.5 observations, although it suffers from non-trivial missing data problems. To address these issues, we developed a multi-stage statistical model in which daily PM2.5 concentrations can be obtained with complete spatial coverage. The model consists of three stages – an inverse probability weighting scheme to correct non-random missing patterns of AOD values, a spatio-temporal linear mixed effect model to account for the spatially and temporally varying PM2.5-AOD relationships, and a gap-filling model based on the integrated nested Laplace approximation-stochastic partial differential equations (INLA-SPDE). Good model performance was achieved from out-of-sample validation as shown in R2 of 0.93 and root mean square error of 9.64 μg/m3. The results indicated that the multi-stage PM2.5 prediction model proposed in the present study yielded highly accurate predictions, while gaining computational efficiency from the INLA-SPDE.  相似文献   

5.
Air quality was improved considerably and the so-called "Lanzhou Blue" appeared frequently in Lanzhou due to implementation of some strict emission-control measures in recent years. To better understand whether the concentration of each air pollutant had decreased significantly and then give some suggestions as to urban air-quality improvement in the near future, the variations of the Air Quality Index (AQI) and six criterion air pollutants (PM2.5, PM10, CO, SO2, NO2, and O3) at five state-controlled monitoring sites of Lanzhou were studied from 2013 to 2016. The AQI, PM2.5, PM10, and SO2 gradually decreased from 2013 to 2016, while CO and NO2 concentrations had slightly increasing trends, especially in urban areas, due to the large number of motor vehicles, which had an annual growth rate of 30.87%. The variations of the air pollutants in the no-domestic-heating season were more significant than those in the domestic-heating season. The increase of ozone concentration for the domestic-heating season at a background station was the most significant among the five monitoring sites. The vehicle-exhaust and ozone pollution was increasingly severe with the rapid increase in the number of motor vehicles. The particulate-matter pollution became slight in the formerly highly polluted Lanzhou City. Some synergetic measures in urban and rural areas of Lanzhou should be taken by the local government in the near future to control fine particulate-matter (PM2.5) and ozone pollution.  相似文献   

6.
Human health effects have been linked to airborne concentrations of fine particulate matter. One source of fine particulate matter in the atmosphere is resuspended soil dust from a variety of activities, including agricultural operations. We have established a method to measure the potential of soil to emit fugitive dust in the PM10 or PM2.5 size range. The method is repeatable, and provides an index of PM10 or PM2.5 dust that is highly correlated to the soil texture. The ratio of the PM2.5 Index to the PM10 Index produced by this method is similar to field observations of ambient PM2.5 and PM10 concentrations downwind of agricultural operations in the San Joaquin Valley of California. The PM2.5 or PM10 Index will be a more useful parameter to estimate the potential of a soil to emit fugitive dust than the currently used dry silt content of soil. Research is currently underway to relate the PM10 and PM2.5 Index to measured emission factors, accounting for soil moisture and type of agricultural operation, so that a more reliable predictive equation can be developed for agricultural practices.  相似文献   

7.
Zhou  Liang  Zhou  Chenghu  Yang  Fan  Che  Lei  Wang  Bo  Sun  Dongqi 《地理学报(英文版)》2019,29(2):253-270

High concentrations of PM2.5 are universally considered as a main cause for haze formation. Therefore, it is important to identify the spatial heterogeneity and influencing factors of PM2.5 concentrations for regional air quality control and management. In this study, PM2.5 data from 2000 to 2015 was determined from an inversion of NASA atmospheric remote sensing images. Using geo-statistics, geographic detectors, and geo-spatial analysis methods, the spatio-temporal evolution patterns and driving factors of PM2.5 concentration in China were evaluated. The main results are as follows. (1) In general, the average concentration of PM2.5 in China increased quickly and reached its peak value in 2006; subsequently, concentrations remained between 21.84 and 35.08 μg/m3. (2) PM2.5 is strikingly heterogeneous in China, with higher concentrations in the north and east than in the south and west. In particular, areas with relatively high PM2.5 concentrations are primarily in four regions, the Huang-Huai-Hai Plain, Lower Yangtze River Delta Plain, Sichuan Basin, and Taklimakan Desert. Among them, Beijing-Tianjin-Hebei Region has the highest concentration of PM2.5. (3) The center of gravity of PM2.5 has generally moved northeastward, which indicates an increasingly serious haze in eastern China. High-value PM2.5 concentrations have moved eastward, while low-value PM2.5 has moved westward. (4) Spatial autocorrelation analysis indicates a significantly positive spatial correlation. The “High-High” PM2.5 agglomeration areas are distributed in the Huang-Huai-Hai Plain, Fenhe-Weihe River Basin, Sichuan Basin, and Jianghan Plain regions. The “Low-Low” PM2.5 agglomeration areas include Inner Mongolia and Heilongjiang, north of the Great Wall, Qinghai-Tibet Plateau, and Taiwan, Hainan, and Fujian and other southeast coastal cities and islands. (5) Geographic detection analysis indicates that both natural and anthropogenic factors account for spatial variations in PM2.5 concentration. Geographical location, population density, automobile quantity, industrial discharge, and straw burning are the main driving forces of PM2.5 concentration in China.

  相似文献   

8.
针对区域大气污染物排放量与空气质量在时空分布上存在不完全协同、匹配的现象,论文选择SO2、NOX、PM2.5、CO和VOCs作为大气污染物指标,选择气溶胶光学厚度(Aerosol Optical Depth, AOD)表征颗粒物环境空气质量,以武汉市为例,综合应用耦合模型和空间错位指数模型研究2类指标之间的空间非协同耦合规律。主要结论如下:① 武汉市大气污染物排放量与颗粒物空气质量具有不同空间分布特征,大气污染物排放量呈现由城市中心城区向远城区递减的趋势,其中SO2、PM2.5和VOCs的排放具有明显的中心聚集现象,而NOX和CO聚集现象不显著,且与道路分布明显相关;AOD分布具有明显的空间差异性,总体上呈由西北向东南依次递减的趋势。② 武汉市大气污染物排放与颗粒物空气质量的空间非协同耦合规律:越靠近城市中心城区,空间协同耦合现象越显著,空间错位现象越弱;越远离主城区,空间非协同耦合现象越显著,空间错位现象越显著;SO2排放量与AOD在武汉市远城区的空间错位指数均大于0.7,且耦合度指数小于0.3,呈现较强的非协同耦合特征,NOX、VOCs、PM2.5的排放量与AOD在武汉中心城区的空间错位指数均小于0.5,且耦合度指数大于0.5,协同耦合现象较为显著。③ 基于时空非协同耦合分析城市大气环境污染治理建议:针对污染物与AOD空间错位不显著的城市中心城区,以本地减排治理为主;针对污染物与AOD空间错位显著的远城区,应在污染溯源分析的基础上进行区域协调综合治理。  相似文献   

9.
This research analyzes the relationship between tropical cyclones and fine particulate matter (PM2.5) for landfalling Atlantic tropical cyclones from 2000 to 2015. Daily mean PM2.5 concentrations were collected from the United States Environmental Protection Agency. Tropical cyclone data were acquired from Tropical Prediction Center Best Track Reanalysis in Unisys weather. GRIdded Binary (GRIB formatted) data were downloaded from the Data Support Section of the Computational and Information Systems Laboratory at the National Center for Atmospheric Research (NCAR). Tracks of tropical cyclones were overlaid with the interpolated daily mean PM2.5 concentration value. Results suggest that, in general, tracks are distant from areas with the largest PM2.5 concentrations. To examine the cause-effect nature of this relationship, simulation using the Weather Research and Forecasting (WRF) model suggests that the intensity of Hurricane Lili was weakened only after passing the most PM2.5-polluted area in Louisiana. This result suggests that aerosol loading may weaken the intensity of tropical cyclones, at least in some cases.  相似文献   

10.
In this article we explore the relationships between urban form and air pollution among 86 U.S. metropolitan areas. Urban form was quantified using preexisting sprawl indexes and spatial metrics applied to remotely sensed land cover data. Air pollution data included the nonpoint source emission of the ozone (O3) precursors nitrogen oxides (NOx) and volatile organic compounds (VOCs), the concentration of O3, the concentration and nonpoint source emission of fine particulate matter (PM2.5), and the emission of carbon dioxide (CO2) from on-road sources. Metropolitan areas that exhibited higher levels of urban sprawl, or sprawl-like urban morphologies, generally exhibited higher concentrations and emissions of air pollution and CO2 when controlling for population, land area, and climate.  相似文献   

11.
ABSTRACT

Spatiotemporal association pattern mining can discover interesting interdependent relationships among various types of geospatial data. However, existing mining methods for spatiotemporal association patterns usually model geographic phenomena as simple spatiotemporal point events. Therefore, they cannot be applied to complex geographic phenomena, which continuously change their properties, shapes or locations, such as storms and air pollution. The most salient feature of such complex geographic phenomena is the geographic dynamic. To fully reveal dynamic characteristics of complex geographic phenomena and discover their associated factors, this research proposes a novel complex event-based spatiotemporal association pattern mining framework. First, a complex geographic event was hierarchically modeled and represented by a new data structure named directed spatiotemporal routes. Then, sequence mining technique was applied to discover the spatiotemporal spread pattern of the complex geographic events. An adaptive spatiotemporal episode pattern mining algorithm was proposed to discover the candidate driving factors for the occurrence of complex geographic events. Finally, the proposed approach was evaluated by analyzing the air pollution in the region of Beijing-Tianjin-Hebei. The experimental results showed that the proposed approach can well address the geographic dynamic of complex geographic phenomena, such as the spatial spreading pattern and spatiotemporal interaction with candidate driving factors.  相似文献   

12.
ABSTRACT

Air pollution has become a serious environmental problem causing severe consequences in our ecology, climate, health, and urban development. Effective and efficient monitoring and mitigation of air pollution require a comprehensive understanding of the air pollution process through a reliable database carrying important information about the spatiotemporal variations of air pollutant concentrations at various spatial and temporal scales. Traditional analysis suffers from the severe insufficiency of data collected by only a few stations. In this study, we propose a rigorous framework for the integration of air pollutant concentration data coming from the ground-based stations, which are spatially sparse but temporally dense, and mobile sensors, which are spatially dense but temporally sparse. Based on the integrated database which is relatively dense in space and time, we then estimate air pollutant concentrations for given location and time by applying a two-step local regression model to the data. This study advances the frontier of basic research in air pollution monitoring via the integration of station and mobile sensors and sets up the stage for further research on other spatiotemporal problems involving multi-source and multi-scale information.  相似文献   

13.
基于绿色出行理念的合肥市区空气污染分区调控研究   总被引:1,自引:1,他引:0  
顾康康  朱鹏祥  宁杨  汪斐 《地理科学》2019,39(8):1312-1320
空气污染是城市主要的环境问题之一,严重影响到城市人类健康,而交通尾气排放是空气污染的重要原因。绿色出行是基于城市可持续发展的要求,通过发展低碳、绿色、环保的出行方式,缓解城市交通拥堵、城市污染等问题的一种交通理念。基于绿色出行理念的城市空气污染分区调控研究,对于改善城市环境质量、提升人居环境品质具有重大意义。以合肥市区为例,构建基于绿色出行理念的城市空气污染评估框架,提出公共交通、步行及自行车的3类绿色出行评价指标,运用大数据分析绿色出行方式降低空气污染物排放的潜力。结果表明:合肥市区公共交通出行呈现东西、南北2条带状分布,步行及自行车出行集中于路网密度较高的城市二环内,“一核两轴”地区的绿色出行条件较好,改善空气污染物排放的潜力较强;城市空气污染空间呈现城市一环、滨湖新区核心区2个凹地;探讨绿色出行与城市空气污染的空间关系,发现两者存在一定的空间权衡关系;最后,基于绿色出行与城市空气污染的空间分布关系,将合肥市区分为绿色出行区、优化建设区、潜力提升区、出行限制区4类区域,并对不同区域提出城市空气污染优化策略。  相似文献   

14.
In this study, PM10, PM2.5, and PM1 concentrations were measured from April through September 2010. These measurements were made every six days and on days with dust events using a Grimm Model 1.177 aerosol spectrometer. Meteorological data were also collected. Overall mean values of 319.6 ± 407.07, 69.5 ± 83.2, and 37.02 ± 34.9 μg/m3 were obtained for PM10, PM2.5, and PM1, respectively, with corresponding maximum values of 5337.6, 910.9, and 495 μg/m3. The presence of the westerly prevailing wind implied that Iraq is the major source of dust events in this area. A total of 72 dust days and 711 dust hours occurred in the study area. The dust events occurred primarily during July. The longest dust event during the study period occurred in July, lasted five days, and had a peak concentration of 2028 μg/m3. These high concentrations produced AQI values of up to 500. A total estimated mortality and morbidity of 1131 and 8157 cases, respectively, can be attributed to these concentrations. The results of this study indicated the importance of dust events in Ahvaz and their possible health impacts. The study also demonstrated the need to design and implement intergovernmental management schemes to effectively mitigate such events.  相似文献   

15.
中国公路交通的重金属排放及其对土地污染的初步估算   总被引:24,自引:3,他引:21  
本文研究了全国各省市机动车Pb、Cu、Zn、Cd排放总量和公路两侧土壤中Pb含量的分布及其面积。结果表明,东部发达省份机动车的重金属排放量较西部地区大。使用含铅汽油的1990~1996年期间,北京市公路两侧土壤中Pb的年输入量为2.48~3.17 mg/ (kg · a)、累积量为11.4 mg/kg;1997~2003年使用无铅汽油后,两者分别下降到0.26~0.29 mg/(kg · a)和1.30 mg/kg。公路两侧的土壤中Pb含量随垂直距离的外延呈指数形式下降。公路交通对道路两侧土壤产生严重和轻度Pb污染的范围分别为距公路0~10 m和10~65 m。2003年北京市和全国受公路交通Pb污染的土地面积为2310 km2和28900 km2。公路交通的重金属排放是导致我国土地污染的重要原因之一。  相似文献   

16.
基于空气污染监测与问卷调查数据,研究了广州中心城区33个社区公园空气污染暴露特征、影响因素及其居民对空气污染感知。主要结论为:1)各区社区公园空气污染暴露风险及其空间格局分布差异较大,低暴露风险公园所占比例较小。2)空气质量指数(AQI)、PM1.0和PM10与社区公园面积呈显著负相关;AQI、PM1.0、PM10和PM2.5与斑块形状指数呈显著正相关关系;二氧化碳(CO2)与离城市主干道距离呈显著负相关,但社区公园1 km缓冲区范围内城市道路密度与其空气污染关系不大。3)超过1/3的居民对社区公园空气污染程度的主观感知优于客观测度的空气污染水平。4)可替代活动空间以及社区公园可达性影响居民空气污染暴露风险。由于社区公园面积规模较小,对空气污染减缓作用有限,未来应尽可能规划面积规模较大、可达性较高、形状更饱满且远离交通主干道的社区公园。  相似文献   

17.
采用便携式空气污染监测设备对广州市环城高速内的中心城区PM2.5污染情况进行移动监测,获取225.7万条频率为1 Hz的PM2.5监测数据,基于此对研究区进行10 m×10 m高时空分辨率的PM2.5污染模拟,并分析移动采集的可靠性及城市中心区PM2.5污染时空模式。结果显示:天气状况稳定条件下移动监测的城市PM2.5数据在时间维度与固定监测站点数据呈现较显著相关性(R 2为0.72~0.86);广州市中心城区的PM2.5污染时空分布在短时间内具有显著的时空分异特征:时间上,干、湿季的平均逐时极差分别为27和11 μg/m3,质量浓度最高值和最低值出现的时段与当天的背景质量浓度值有关;空间上,交通枢纽、商业中心、工业园和大型商贸市场附近PM2.5污染风险高,公园绿地、高校、高级住宅区等风险相对较低,且呈干季西高东低、南高北低,湿季东高西低的空间分异特征。  相似文献   

18.
饶婧雯  马静  柴彦威 《地理研究》2022,41(4):1183-1193
已有关于空气污染与幸福感的文献主要使用空气质量监测点的数据探讨基于居住地的静态污染暴露与居民长期幸福感的关系,缺乏考虑时空行为视角下的实时动态空气污染暴露对日常活动满意度的影响机理。根据2017年北京居民日常活动与环境健康调查数据,探讨不同活动属性的主客观空气污染暴露及活动满意度的时空差异,分析基于实时空气污染暴露的社会分异,并利用结构方程模型挖掘个人社会经济属性、居民日常活动特征、以及不同活动地点实时测度和主观感知的空气污染水平对活动满意度的影响机制及作用路径。结果表明:不同社会经济属性群体由于日常活动所处的微观环境不同,承受的实时空气污染暴露存在显著的社会分异;客观空气污染对活动满意度的直接影响并不显著,但能显著影响主观空气污染评价,而主观空气污染评价则能显著降低活动满意度,因此客观空气污染主要通过影响主观污染评价进而对活动满意度产生显著的间接效应。此外,空气污染会调节社会经济属性对活动满意度的影响效应。  相似文献   

19.
利用2011年秋冬季榆林大气成分站黑碳浓度、颗粒物质量浓度、大气能见度、地面气象资料,计算边界层高度、气溶胶吸收系数、大气消光系数,导出单次散射反照率,并对其进行分析讨论。结果表明:(1) 榆林秋冬季平均黑碳浓度为2.6 μg·m-3。(2)黑碳占颗粒物质量浓度PM1.0比值为10.6%,黑碳与颗粒物质量浓度PM1.0、PM2.5、PM10相关系数分别为0.91、0.91、0.72。(3)黑碳浓度受边界层高度影响,沙漠风场对黑碳的堆积输送起主导作用。(4) 榆林地区气溶胶吸收系数与大气消光系数比值为16.8%。(5)单次散射反照率平均值为0.72。  相似文献   

20.
Greenhouse-gas (GHG) emissions in China have aroused much interest, and not least in recent evidence of their reduction. Our intent is to place that reduction in a larger context, that of the process of industrialization. A lengthy time perspective is combined with a cross-sectional approachChina plus five other countries-and addressed through two general models. The findings are salutary. First, they suggest that a diversified economic structure is consistent with diminished intensity in energy use. Secondly, and the obverse of the first, they imply that a diversified energy structure promotes reductions in CO2 emissions. Finally, one is led inevitably to the conclusion that, together, the findings point to a path for countries to transform their economies while at the same time undertaking to drastically moderate their energy use, switching from a pattern of heavy carbon emissions to one in which lighter carbon emissions prevail. The implications of such findings for environmental management are enormous.  相似文献   

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