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1.
通过资料分析和数值模拟开展了2015年8月1日—10日台风“苏迪罗”对珠三角地区臭氧(O3)污染影响的机理研究。结果表明,2015年8月5—8日,在台风接近登陆点的过程中,台风外围天气导致了高温、高辐射和静小风等气象条件,促进了光化学反应的进行和污染物的局地积累。同时,高温、高辐射等气象条件加剧了植被源区生物源挥发性有机物(BVOCs)的排放。采用化学传输模式模拟发现,植被BVOCs对O3污染的贡献最高可达24×10-9。结合拉格朗日粒子扩散模式(LPDM)探索了影响珠三角地区的主导气团,发现珠三角城市地区和高BVOCs源区存在交互传输的现象。污染期间,高BVOCs源区的一次排放产物(BVOCs)和二次产物(O3)经区域输送加剧了珠三角地区O3的污染。此外,研究发现台风外围条件下珠三角内陆盛行的偏北风与海陆热力差异引起的海风在沿海地区辐合,造成污染物局地积累,加剧并延长了O3污染。研究有利于加强对O3污染机理的认识,进而更好地采取针对性措施,有助于减小O3污染带来的危害。  相似文献   

2.
大气污染对城市绿化植物叶片叶绿素含量的影响   总被引:8,自引:0,他引:8  
研究了南阳市城市大气对该市5种常见城市绿化植物叶片叶绿素(a、b)含量比例(Ca/Cb)以及叶片叶绿素总含量(Ct)的影响。通过研究发现,污染严重的南阳卷烟厂区域植物叶片叶绿素Ca/Cb值相对较高,叶绿素总含量(Ct)相对较低;无污染的对照区域(南阳师范学院院内绿化区)植物叶片叶绿素Ca/Cb值相对较低,叶片叶绿素总含量(Ct)相对较高。通过数据分析,进一步得出了5种常见城市绿化植物抗大气污染能力的大小:女贞>大叶黄杨>月季>金叶女贞>三叶草。  相似文献   

3.
  1. The Air Polluttion Monitoring System has got a significant development of late, which is in direct relation with a considerable extention and improvement of the observation network in cities and industrial areas, with creation of a new network for assessing regional and global background of the atmosphere pollution, as well as with the wide involvement of meteorologists to monitoring organization.
  2. While developing a new global monitoring system, it is necessary to take into account its relationship with the local monitoring within the region of air pollution sources, i.e. at the \lsimpact\rs level. The need in such an account is dictated first of all by the physics of pollutant spreading that states: changes in air pollution over large territories must be in a certain agreement with greater changes in the vicinity of emission sources. Methods applied in the global and local monitoring have also a number of common peculiarities. White organizing regional network for observations of the background pollution of the atmosphere twin stations (one of the pair of stations located outside the city boundaries in a small community, and the other, in the nearest city with the population of 200–400 thousand inhabitants) were established in the U.S.S.R. and in a number of socialist countries in Europe.
  3. Implementation of the twin-station principles in the U.S.S.R. has contributed to data interpretation and representativity assessment as well as to correction of the station location. Observation results from the Soviet background stations and those abroad have been compared by now according to a number of indices.
  4. The correlation of monitoring systems of various scales tells positively both on mutual improvement and completion of observational methods. The methods of obtaining integral characteristics of air pollution were used for the global monitoring, in particular spectral actinometric observations and chemical analysis of the precipitation composition. Now they find still wider employment. Thus methods of spectral actinometric measurements and data processing were used to estimate the degree of aerosol pollution of a number of industrial centres. The theory of solar radiation spreading and aerosol contents determination in urban atmosphere has also been developed. It is a generalization of an earlier developed theory, used to estimate global atmosphere pollution basing on actinometric data. The organization of precipitation collection and analysis on a network of stations around Leningrad and in Donbass area enables us to compare the admixture content in precipitations falling in industrial and agricultural areas.
  5. A considerable increase of possibilities to measure microconcentrations of sulphur dioxide, nitrogen oxides and of a number of other pollutants is connected with the use of solid solvents for sampling. Their use will allow to avoid establishment of special laboratories at background stations and only send samples by post for their analysis in centralized laboratories.
They will also allow to considerably increase precision and accuracy of measurements. The international comparisons of methods of air pollution measurements on the background level allow to judge about the effiency of these methods.  相似文献   

4.
The morphology, microstructure, and chemical composition of a variety of particles emitted from coal-fired power plants, steel plants, and vehicle exhausts, which are possible sources of particulate matter (PM) in the atmosphere, were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and compared with particle samples collected from urban atmosphere to identify the best footprint or the suitable indicator relating the existence of studied particles and their possible emitters by the morphology, microstructure, and chemical composition of the particles. The investigation indicated that the particles from these three sources are different in morphology, microstructure, and chemical composition. Sphere aggregates were generally the most abundant components, with silicon and aluminum as major elements. The urban air particulate contained particles similar to those observed in the power plant, steel plant, and vehicle exhaust samples suggesting that all three sources are contributing to the pollution in the city.  相似文献   

5.
南京市一次连续空气污染过程的气象条件分析   总被引:1,自引:0,他引:1  
利用空气污染资料、常规气象观测资料、NCEP每6h一次2.5°×2.5°再分析资料及NOAA(美国国家海洋和大气管理局)的GDAS(全球同化数据)资料,对2009年10月16日—30日南京市出现一次连续15d的空气污染过程的天气特征进行诊断分析,同时使用HYSPLIT-4后向轨迹模式对污染物来源进行模拟。结果表明:不利于污染物扩散的大气环流形势和气象要素是造成此次污染的主要原因。南京污染物的来源可以大致分为3类:一类是海上来源;一类是南京本地的局地污染来源;还有一类是北方污染物的输送。这为进一步研究长三角地区城市的空气污染来源和成因提供理论依据。  相似文献   

6.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October-December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   

7.
A field study was carried out at six locations in the Lazio region (Central Italy) aimed at characterising atmospheric particulate matter (PM10 and PM2.5) from the point of view of the chemical composition and grain size distribution of the particles, the mixing properties of the atmosphere, the frequency and relevance of natural events. The combination of four different analytical techniques (ion chromatography, X-ray fluorescence and ICP for inorganic components, thermo-optical analysis for carbon compounds) yielded sound results in terms of characterisation of the air masses. During the first three months of the study (October–December 2004), many pollution events of natural (sea-salt or desert dust episodes) or anthropogenic nature were identified and characterised. More than 90% of the collected mass was identified by chemical analysis. The central role played by the mixing properties of the lower atmosphere when pollution events occurred was highlighted. The results show a major impact of primary anthropogenic pollutants on traffic stations and a homogeneous distribution of secondary pollutants over the regional area. An evaluation of the sources of PM and an identification of possible reliable tracers were obtained using a chemical fractionation procedure.  相似文献   

8.
为了解石家庄市2016年春季大气颗粒物的铅污染特征及来源,利用单颗粒气溶胶质谱仪(SPAMS),分析了大气中含铅颗粒的化学成分。结果表明: 研究期间大气环境中含铅颗粒数浓度共出现11次跳跃式升高,跳跃时间段内石家庄均处于轻度污染过程。从成分分析来看,含铅颗粒分为纯铅颗粒、Pb与K(Pb-K)、OC(Pb-OC)、Cl(Pb-Cl)、混合颗粒等八大类。观测结果表明:Pb-K颗粒最多,占到含铅颗粒的84.4%;其次为纯铅颗粒,占比为13.0%。与石家庄市污染源谱库比对进行来源解析,得到Pb-K颗粒主要来自生活垃圾焚烧源, 纯铅颗粒主要来自工业源。结合石家庄市大气污染源排放清单和后向气流轨迹分析,推测含铅颗粒可能来自市区西南方向某区县的生活垃圾焚烧企业。  相似文献   

9.
The air pollution due to anthropogenic activities seriously affected human life, vegetation, and heritage as well. The vegetation cover in and around the city mitigates the air pollution by acting as a sink for pollution. An attempt was made to evaluate biochemical changes occurred in four selected plant species, namely Azadirachta indica, Mangifera indica, Delonix regia, and Cassia fistula of residential, commercial, and industrial areas of Nagpur city in India. It was observed that the correlated values of air pollutants and plant leaves characteristics alter foliar biochemical features (i.e., chlorophyll and ascorbic acid content, pH and relative water content) of plants due to air pollution. The changes in air pollution tolerance index of plants was also estimated which revealed that these plants can be used as a biomarker of air pollution.  相似文献   

10.
Integrated pollution evaluation of the Tagus River in Central Spain   总被引:1,自引:0,他引:1  
The aim of this study was to integrate hydrochemical and sediment data in order to obtain a picture of the pollution state of the Tagus River along central Spain. This area is of special interest because tributaries from the Madrid region are discharged and no previous data were available. Waters and sediments were sampled between 2002 and 2004 from selected sites before and after Jarama River confluence (Madrid city input). The samples were analysed for more than 50 parameters, including those of physico-chemical nature and those reporting the pollution caused by both metals and organic compounds. The quality of waters for different uses has been tested and statistical quality indexes of both global and partial type has also been established. Sediments pollution state was evaluated by comparison with general quality standards. A high degree of pollution and general degradation was observed in the Tagus River downstream the Jarama River input. The pollution of waters is mainly related to parameters indicators of organic pollution from urban sewage. In sediments, a dramatic increase in the concentration of trace metals was found in different points, exceeding toxicological threshold. Further studies would be necessary for organic pollutants and also to evaluate the remobilization potential.  相似文献   

11.
洛阳市大气污染特征与相关气象要素24小时变化分析   总被引:10,自引:0,他引:10  
通过对洛阳市环境空气监测资料的统计,归纳出洛阳市区日内24小时环境空气污染变化特征,并结合同步气象观测资料综合分析,找出了二者之间的联系特征。引入气温日较差这一便于观测、预报的气象要素表征空气污染物垂直扩散特征,为今后进行污染预报提供了新的思路。  相似文献   

12.
研究SO_2与硫酸盐化速率的相关关系,以GB3095-82(大气环境质量标准)中的SO2标准为基础,并借鉴国外先进国家的标准和硫酸盐化速率植物试验的成果,结合南京市大气环境质量现状,制定适合于南京地区的大气硫酸盐化速率建议标准.  相似文献   

13.
Seasonal Variation of Toxic Benzene Emissions in Petroleum Refinery   总被引:1,自引:0,他引:1  
Petroleum refineries are largest chemical industries that are responsible for the emission of several pollutants into the atmosphere. Benzene is among the most important air pollutants that are emitted by petroleum refineries, since they are involved in almost every refinery process. Volatile organic compounds (VOCs) are a major group of air pollutants, which play a critical role in atmospheric chemistry. These contribute to toxic oxidants, which are harmful to ecosystem, human health and atmosphere. The variability of pollutants is an important factor in determining human exposure to these chemicals. The ambient air concentrations of benzene were measured in several sites around the Digboi petroleum refinery, near the city of Gowahati in northeast India, during winter and summer 2004. The seasonal and spatial variations of the ambient air concentrations of this benzene were investigated and analyzed. An estimation of the contribution of the refinery to the measured atmospheric levels of benzene was also performed. The ambient air mixing ratios of benzene in a large area outside the refinery was generally low, in ppbv range, much lower than the ambient air quality standards. This article presents the temporal and spatial variation of air pollution in and around petroleum refinery and showed that no health risk due to benzene is present in the areas adjacent to the refinery.  相似文献   

14.
博乐市空气质量变化趋势分析   总被引:2,自引:0,他引:2  
分析了博乐市2001-2005年空气质量监测数据在不同月份、不同年份、不同污染因子的变化趋势,并结合当地能源结构、地理位置、气候特征、城市环境综合发展水平。指出影响博乐市空气质量的主要因素,为防治或减轻博乐地区的空气污染提供了科学依据。  相似文献   

15.
The Tamsui River basin is located in Northern Taiwan and encompasses the most metropolitan city in Taiwan, Taipei City. The Taiwan Environmental Protection Administration (EPA) has established 38 water quality monitoring stations in the Tamsui River basin and performed regular river water quality monitoring for the past two decades. Because of the limited budget of the Taiwan EPA, adjusting the monitoring program while maintaining water quality data is critical. Multivariate analysis methods, such as cluster analysis (CA), factor analysis (FA), and discriminate analysis (DA), are useful tools for the statistically spatial assessment of surface water quality. This study integrated CA, FA, and DA to evaluate the spatial variance of water quality in the metropolitan city of Taipei. Performing CA involved categorizing monitoring stations into three groups: high-, moderate-, and low-pollution areas. In addition, this categorization of monitoring stations was in agreement with that of the assessment that involved using the simple river pollution index. Four latent factors that predominantly influence the river water quality of the Tamsui River basin are assessed using FA: anthropogenic pollution, the nitrification process, seawater intrusion, and geological and weathering processes. We plotted a spatial pattern using the four latent factor scores and identified ten redundant monitoring stations near each upstream station with the same score pattern. We extracted five significant parameters by using DA: total organic carbon, total phosphorus, As, Cu, and nitrate, with spatial variance to differentiate them from the polluted condition of the group obtained by using CA. Finally, this study suggests that the Taiwan EPA can adjust the surface water-monitoring program of the Tamsui River by reducing the monitoring stations to 28 and the measured chemical parameters to five to lower monitoring costs.  相似文献   

16.
Epidemiological studies typically use monitored air pollution data from a single station or as averaged data from several stations to estimate population exposure. In industrialized urban areas, this approach may present critical issues due to the spatial complexities of air pollutants which are emitted by different sources. This study focused on the city of Taranto, which is one of the most highly industrialized cities in southern Italy. Epidemiological studies have revealed several critical situations in this area, in terms of mortality excess and short-term health effects of air pollution. The aims of this paper are to study the variability of air pollutants in the city of Taranto and to interpret the results in relation to the applicability of the data in assessing population exposure. Meteorological and pollution data (SO2, NO2, PM10), measured simultaneously and continuously during the period 2006–2010 in five air quality stations, were analyzed. Relative and absolute spatial concentration variations were investigated by means of statistical indexes. Results show significant differences among stations. The highest correlation between stations was observed for PM10 concentrations, while critical values were found for NO2. The worst values were observed for the SO2 series. The high values of 90th percentile of differences between pairs of monitoring sites for the three pollutants index suggest that mean concentrations differ by large amounts from site to site. The overall analysis supports the hypothesis that various parts of the city are differently affected by the different emission sources, depending on meteorological conditions. In particular, analysis revealed that the influence of the industrial site may be primarily identified with the series of SO2 data which exhibit higher mean concentration values and positive correlations with wind intensity when the monitoring station is downwind from the industrial site. Results suggest evaluating the population exposure to air pollutants in industrialized cities by taking into account the possible zones of influence of different emission sources. More research is needed to identify an indicator, which ought to be a synthesis of several pollutants, and take into account the meteorological variables.  相似文献   

17.
根据丹江口库区及其上游河流5个区域42个断面2012-2013年的水质监测数据,采用主成分分析法确定主要污染因子及权重,对不同流域的水质进行综合评价。第一主成分包括总氮、溶解氧、五日生化需氧量、总磷、氨氮、高锰酸盐指数,第二主成分为氟化物、粪大肠菌群,第三主成分为化学需氧量;其权重分别为5.022,2.256,1.508。评价结果表明,湖北十堰市和丹江口市流域水环境污染相对较重,其次为河南南阳市、陕西商洛市、陕西安康市以及陕西汉中市流域。  相似文献   

18.
The Bormida River Basin, located in the northwestern region of Italy, has been strongly contaminated by the ACNA chemical factory. This factory was in operation from 1892 to 1998, and contamination from the factory has had deleterious consequences on the water quality, agriculture, natural ecosystems and human health. Attempts have been made to remediate the site. The aims of this study were to use high-resolution satellite images combined with a classical remote sensing methodology to monitor vegetation conditions along the Bormida River, both upstream and downstream of the ACNA chemical factory site, and to compare the results obtained at different times before and after the remediation process. The trends of the Normalised Difference Vegetation Index (NDVI) and the Enhanced Vegetation Index (EVI) along the riverbanks are used to assess the effect of water pollution on vegetation. NDVI and EVI values show that the contamination produced by the ACNA factory had less severe effects in the year 2007, when most of the remediation activities were concluded, than in 2006 and 2003. In 2007, the contamination effects were noticeable up to 6 km downstream of the factory, whereas in 2003 and 2006 the influence range was up to about 12 km downstream of the factory. The results of this study show the effectiveness of remediation activities that have been taking place in this area. In addition, the comparison between NDVI and EVI shows that the EVI is more suitable to characterise the vegetation health and can be considered an additional tool to assess vegetation health and to monitor restoration activities.  相似文献   

19.
三明市酸、碱降水成因研究   总被引:4,自引:0,他引:4  
三明市属福建省内陆山区,在东、西相差仅四公里的两个测点,常常一边下硫酸盐型酸雨,一边下钙盐型碱雨这一特殊降水过程。从离子成分、离子浓度比进行分析,并从局地污染源、气象等因素就其成因作了探索性研究,将影响降水pH值的污染因子进行灰色关联优势分析。结果表明,三明市降水污染相当严重,在重视酸性降水污染的同时,也不应忽视污染更为严重的碱性降水  相似文献   

20.
近年来,随着城市化进程推,城市生态环境正逐步恶化。徐州作为老矿业城市,情况尤其不为乐观,以徐州市区为例作生态评价分析。按照代表性、可操作性、适应性、可比性和方便性原则,选取了植被覆盖度、生物丰度、水网密度、人均绿地面积、城市环境污染负荷指数和环境质量综合指数作为评价指标来进行生态环境质量指数的计算。根据评价指标,选用1994年、2000年和2007年三个时相徐州市TM影像,对土地利用、河流水库、植被、人均绿地等方面进行遥感动态监测,然后对该地区13年来生态环境演变做了定量评价分析。评价结果表明,徐州市区生态环境质量由1994年的良好水平退化为一般水平,且有逐年下降恶化趋势,这与该区城市化进程一致。  相似文献   

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