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1.
In the year 2000, the elemental composition of mosses collected from 528 French sites has been studied as part of the 2000 European Moss Survey. Five moss species were collected: Scleropodium purum (56%), Pleurozium schreberi (18%), Hypnum cupressiforme (18%), Thuidium tamariscinum (4.5%.) and Hylocomium splendens (3.5%). Mosses were kept whole for analysis, including green and brownish parts. Summary statistics on element concentrations (Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Li, Mg, Mn, Na, Ni, P, Pb, Rb, Sr, V and Zn), and comparisons made with data from the other 27 participating European countries are shown here. The sources of these elements are identified using calculations of enrichment factors (EF) and principal component analysis (PCA). Finally, the spatial distribution in France of 10 elements is also shown, using maps underscoring areas showing highest concentration levels for each metal.  相似文献   

2.
Total suspended particulates(TSP)samples were collected using low pressure impactors(Andersen Series 20-800,USA)on typical clear,hazy and foggy days in Beijing in order to investigate the characteristics of size distributions and elemental compositions of particulate matter(PM)in different weather conditions. The concentrations of sixteen elements,including Na,Mg,Al,K,Ca,Mn,Fe,Ni,Cu,Zn,As,Se,Cd,Ba,Tl and Pb were detected using inductively coupled plasma mass spectrometry(ICP-MS).The results showed that Ca,Al,Fe,Mg and Ba on foggy days were 2.0-2.6 times higher than on clear days,and 2.3-2.9 times higher than on hazy days.Concentrations of Cu,Zn,As,Se and Pb on foggy days were 163.5,1186.7,65.9,32.0 and 708.2 ng m-3,respectively,in fine particles,and 68.1,289.5,19.8,1.6 and 103.8 ng m-3,respectively,in coarse particles.This was 1.0-8.4 times higher and 1.4-7.4 times higher than on clear and hazy days,respectively.It is then shown that Mg,Al,Fe,Ca and Ba were mainly associated with coarse particles,peaking at 4.7-5.8μm;that Cd,Se,Zn,As,Tl and Pb were most dominant in fine particles,peaking at 0.43-1.1μm;and that Na,K,Ni,Cu and Mn had a multi-mode distribution,with peaks at 0.43-1.1μm and 4.7-5.8μm.The enrichment factors indicated that coal combustion along with vehicle and industry emissions may be the main sources of pollution elements.  相似文献   

3.
Concentrations of the elements Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn were measured in the moss Pleurozium schreberi from the Tatra National Park, one of the most protected regions in Poland. The moss samples were collected at different elevations between 860 and 2220 m a.s.l. P. schreberi was used as bioindicator for long range transported atmospheric pollution investigating the hypothesis that elevation influences the concentrations of elements in this moss. Principal component and classification analysis (PCCA) distinguished between mosses from the highest and the lowest elevations and mosses from West/East oriented valleys. P. schreberi from the highest elevations contained the highest concentrations of Cd, Cu, Cr, Fe, Mn, Pb, V and Zn. P. schreberi from the lowest elevation contained the highest concentration of K. P. schreberi from West/East oriented valleys contained the highest concentrations of Ni and Co. P. schreberi from the Tatra National Park, one of the most protected areas in Poland, receives metals originating from long distance aerial transport.  相似文献   

4.
大气气溶胶虚折射指数及其与元素的相关性   总被引:7,自引:1,他引:7       下载免费PDF全文
在西安、南京采集111个气溶胶样品,测定了虚折射率ni和分析了粒子中Si、Al、Ca、Fe、K、Mg、Mn、Na、Ti、S、P、Pb和Zn的含量。统计分析表明,ni与S和Pb的相关系数r最高,分别为0.36和0.30,统计检验也表明,这一相关性是显著的。其它11种元素与ni的相关性较差,且并不显著。西安气溶胶S含量明显高于南京,它与ni之间的相关系数高出南京近一倍。这些结果表明,除碳C之外,气溶胶中的S和Pb及其化合物对辐射的吸收不能忽视。  相似文献   

5.
The data on deposition density of Ag, Al, As, B, Ba, Be, Bi, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, I, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Se, Si, Sn, Sr, Th, Tl, U, V, Zn, Cl?, F?, NO 3 ? , and SO 4 2? in atmospheric precipitation were derived at six stations in the Republic of Karelia. The structure and space-time distribution of five sets (factors) of chemical components of the first order and two factors of the second order are revealed with the help of hierarchical factor analysis. Factor analysis of the second order demonstrated that atmospheric precipitation chemistry at all stations considered differs greatly in the winter and summer, forming two independent sets of components. The first-order factors revealed chemical indicators characterizing specific features of the atmospheric precipitation chemistry in the Karelian regions studied.  相似文献   

6.
The chemistry of rainwater was studied in three sites of a metropolitan city of Turkey to determine the spatial variation, sources affecting composition and the extent of their influence. The acidity of rainwater, Ca, Co, Cr, Zn, Ba, V and Ni showed significant spatial variations. The most of measured species were moderately to extremely enriched compared to the local soil, which is likely arisen from the anthropogenic activities. SO4 2?, K and Ca were found to be predominantly non-sea origin. Two receptor models, Positive Matrix Factorization (PMF) and Chemical Mass Balance (CMB), agreed well on the source contribution estimations of Al, K, Zn, V, Pb and Cr. The PMF and CMB resolved very similar source contribution profiles to the elemental concentrations of Ca, Zn, V, Pb, K and Na, which the majority of those resulted from mineral industries, bell casting+steel industries, fossil fuel burning, biomass burning+sea salt and sea salt, respectively. The PMF resolved the source contributions of long-transported emissions, particularly for Ba, Sr and Mn, which could not be estimated by the CMB.  相似文献   

7.
In order to investigate the chemical characteristics of atmospheric aerosols in a regional background site, PM2.5 and PM10 were collected at Mount Gongga Station once a week in 2006. The concentrations of fifteen elements including Na, Mg, Al, K, Ca, V, Fe, Ni, Cu, Zn, As, Ag, Ba, Tl, and Pb were detected by Inductively Coupled Plasma Mass Spectrometer (ICP-MS). The results showed that Na, Mg, Al, K, Ca, Fe were the major components of elements detected in PM2.5 and PM10, occupied 89.5% and 91.3% of all the elements. Crustal enrichment factor (EF) calculation indicated that several anthropogenic heavy metals (Ni, Cu, Zn, As, Ag, Tl, Pb) were transported long distances atmospherically. The concentrations of all elements (except Na) measured in PM2.5 and PM10 in spring and winter were higher than those in summer and autumn. The backward air mass trajectory analysis suggests that northeast India may be the source region of those pollutants.  相似文献   

8.
The concentration of Si, Al, Mg, K, Ca, Na, Sr, and Ba in the subcolloidal fraction of sediments at the Razdol’naya River-Amur Bay cross-section is determined using the atomic emission spectroscopy method. Computed is the mean content of studied elements in the soil and river bottom sediments (to the mixing zone). Revealed are river bottom sediments with the high concentration of macroelements corresponding to the zone of mixing of fresh river water and salt sea water. It is demonstrated that the additional accumulation of macroelements (Ca, Na, and Sr) in these sediments is associated with the formation of hydroxides of Fe and Mn and processes of sorption (Mg, Ca, Na, K, Sr, and Ba) on clay minerals (hydromica and smectites).  相似文献   

9.
Data on deposition density of Ag, Al, As, B, Ba, Bi, Br, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Sb, Si, Sn, Sr, Th, Tl, U, V, Zn, Cl?, NO 3 ? , and SO4 4 2? in atmospheric precipitation were derived at 11 observation stations in the northern part of the European territory of Russia (ETR). Three sets (factors) of chemical indices that are mutually independent and determine the precipitation chemical content over that territory were revealed by using the hierarchical factor analysis of deposited density of chemical ingredients studied. These are two first-order factors: one is presented with the elements of a “marine” origin; the second is associated with biogenic elements. The second-order factor is formed by the ingredients characteristic of the combustion products of different fossil fuels. The structure and space-time distribution of factors are considered. The discriminant and cluster analyses allowed to classify the observation stations considered by the atmospheric precipitation chemistry and to show that Amderma, Vorkuta, Arkhangelsk, and Kargopol stations mostly differ from each other.  相似文献   

10.
A biomonitoring survey using the moss species Hypnum cupressiforme Hedw. was performed in the North of Navarra (Spain) in 2006. The levels of V, Cr, Mn, Ni, Cu, Zn, As, Zr, Cd, Hg and Pb, and the total nitrogen content were determined in the samples by means of ICP-MS, CV-AA, and the Kjeldahl method. PCA analysis showed a differentiation between lithogenic (V, Cr, Mn, Ni, As and Zr) and anthropogenic elements (Mn, Cu, Zn, Cd, Hg and Pb). Spatial distribution maps were drawn using the kriging method, in order to identify the most affected areas and the main pollution sources. A similar spatial distribution was observed for the elements belonging to each group separated by the PCA, showing an important contribution from metal industries located in the Basque Country, as well as influence of long-range transboundary pollution processes. Background levels were also determined for the study area, along with the contamination factor for the different elements analysed. Mosses seemed to be good biomonitors of N deposition in areas of accumulation.  相似文献   

11.
Mass size distribution of the crustal elements (Al, Ca, Fe, Mg, Si, Ti), anthropogenic elements (Zn, Mn, Cr, Cu, K, P, Pb) and sea elements (Na, Cl) were obtained from measurements carried out with an inertial cascade impactor in Sfax. A fitting procedure by data inversion was applied to those data. This procedure yields accurate size distributions of aerosols in the diameter range 0.1–25 μm in two different sites. In a coastal industrial site, the mass distribution of the aerosol showed a bimodal structure; and in urban area, the lower particle mode cannot be observed. The elemental dry deposition flux was calculated as a function of particle size. The element flux size distribution increased rapidly with particle size. The modelling results indicate that the majority of the crustal and anthropogenic elements flux (>90%) was due to particles larger than 3 μm in diameter.  相似文献   

12.
To test the ability of Hylocomium splendens segments to retain absorbed heavy metals (Fe, V and Pb) and some physiological elements (Ca, Mg and K) over a period of some years, moss turf was cross-transplanted between polluted and background sites. Thereby it was possible to determine how quickly the concentrations in moss can reach chemical equilibrium with the atmospheric inputs. At a particular site (background or polluted), the physiological elements in transplanted material quickly reached the levels in the non-transplanted moss. For the heavy metals, the concentrations remained stable over 3 years in moss cross-transplanted from a polluted to a background site. There appeared to be inherent differences between moss at the background and polluted sites in the ability to absorb and accumulate heavy metals.  相似文献   

13.
利用环境扫描电镜(SEM/EDS)分别对2009年四季在雷达站、卫星站、年轮实验室和白杨沟站采集的TSP样品进行微观形貌和能谱分析,结果表明:乌鲁木齐市TSP形貌具有明显的时空分布特征。春季TSP颗粒较大,形状不规则,可能来源沙尘;夏季TSP中颗粒少且小,可能含有土壤扬尘和植物花粉;秋季TSP颗粒多为蓬松链状,可能是烟尘聚集体;冬季TSP颗粒较大,形状规则的颗粒增多且多为圆形,是典型的燃煤飞灰形态。北郊、市区TSP中颗粒物数量高于南郊山区的白杨沟站,秋冬季燃煤对北郊和市区TSP形貌影响较大。TSP主要含Si、S、Ca、Al、Fe、Mg、Cl、Na,说明TSP来源广泛,并且由多种颗粒混合而成。春夏季乌市TSP中Si、Ca Al、Na、Mg含量较高,秋冬季Si、S、Ca、Al、Fe、Cl含量很高。市区TSP中S、Fe、Al较白杨沟同期所占比重大,白杨沟TSP中元素种类较少,S、Fe含量不高,表明燃煤、工业排放影响不大。  相似文献   

14.
To determine the effects of long-range transport of aerosols from an upwind area in East Asia to a downwind area in Japan, we chemically analyzed aerosols collected simultaneously on Tuoji Island (Shandong Province, China), Fukue Island (Nagasaki Prefecture, Japan), and Cape Hedo (Okinawa Prefecture, Japan). We focused on changes in the metallic composition of PM2.5 aerosols during long-range transport. The average mass concentrations of PM2.5 at the three sites decreased in the order Tuoji Island > Fukue Island ≈ Cape Hedo (48.3 ± 4.5, 13.9 ± 1.5, and 13.2 ± 0.9 μg/m3, respectively). The fraction of coarse particles in total suspended particles estimated by (1–PM2.5/TSP) was highest on Cape Hedo, indicating that the contribution of sea salts was increased by long-range transport of the aerosols over the ocean. Enrichment factor analysis revealed that at all three sites, Al, K, Ca, Mn, Fe, Co, Sr, and Ba originated from soil; whereas Cr, Ni, Cu, Zn, As, Mo, Ag, Cd, Sn, Sb, Tl, and P appeared to be of anthropogenic origin. Na was the most abundant element on Cape Hedo, indicating the addition of sea salts during aerosol transport. The V concentration was highest at Fukue Island, which was ascribed to V emission from ships. Sixty-one percent of the V on Fukue Island and 62% of the V on Cape Hedo were determined to have originated from ships, implicating of data obtained on dates during which backward trajectory analysis indicated that the same air mass passed over Tuoji Island, Fukue Island, and Cape Hedo in that order.  相似文献   

15.
Epidemiological studies initially considered the impact of total solid particles on human health, but according to the acquired knowledge about the worse effect of smaller particles, those studies turned to consider the impact of PM10. However, for the last decade PM2.5 began to be more important, once as they are smaller they can penetrate deeper in the lungs, being possible their trapping in alveoli and worse effects on human health. Therefore, more information on PM2.5 should be provided namely concerning the levels and elemental composition. Considering the relevance of traffic on the emission of particles of small sizes, this work included the detailed characterization of PM10 and PM2.5, sampled at two sites directly influenced by traffic, as well as at two reference sites, aiming a further evaluation of the influence of PM10 and PM2.5 on public health. The specific objectives were to study the influence of traffic emission on PM10 and PM2.5 characteristics, considering concentration, size distribution and elemental composition. PM10 and PM2.5 samples were collected using low-volume samplers; the element analyses were performed by particle induced X-ray emission (PIXE). At the sites influenced by traffic emissions PM10 and PM2.5 concentrations were 7–9 and 6–7 times higher than at the background sites. The presence of 17 elements (Mg, Al, Si, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb) was determined in both PM fractions; particle metal contents were 3–44 and 3–27 times higher for PM10 and PM2.5, respectively, than at the backgrounds sites. The elements originated mostly from anthropogenic activities (S, K, V, Mn, Ni, Zn and Pb) were predominantly present in PM2.5, while the elements mostly originated from crust (Mg, Al, Si and Ca) predominantly occurred in PM2.5–10. The results also showed that in coastal areas sea salt spray is an important source of particles, influencing PM concentration and distributions (PM10 increased by 46%, PM2.5/PM10 decreased by 26%), as well as PM compositions (Cl in PM10 was 11 times higher).  相似文献   

16.
The effects of growth of autoirrigated, shaded transplants of Pseudoscleropodium purum on the quantification of tissue concentrations of Cd, Cu, Hg, V and Zn, were investigated in 4 exposure periods, each of 56 days, at 7 sampling sites (contaminated and uncontaminated). Concentrations of the elements in the basal portions of the moss shoots were compared with the concentrations in the portions of the shoots that grew during the exposure period. Mercury and V were present at lower concentrations in the new portions of the shoots than in the basal portions, whereas the opposite was true for Cd, Cu and Zn. The magnitude of error introduced by growth was not negligible, and in some cases was higher than 40%, relative to the results obtained by analysis of the whole shoot. Devitalization of moss prior to its use as transplant material is recommended to avoid growth of the plant during the exposure period.  相似文献   

17.
Ambient suspended particles (TSP) were collected from January to June 2001 at seven sampling sites in western Macedonia, Greece, where four thermal power stations are located. TSP samples were chemically characterized for minerals (Fe, Al, Mg, Ca, K, Ti and Si), trace elements (P, Cd, Cr, Cu, Mn, Pb, V, Zn, Te, Co, Ni, Se, Sr, As, and Sb), water-soluble ions , carbonaceous compounds (OC/EC) and polycyclic aromatic hydrocarbons (PAHs). These classes of compounds were consequently compared with PM mass concentrations of TSP in order to perform mass closure. PM chemical compositions exhibited differences at the seven sites. Minerals were found to be more abundant at four sites, electrolytes dominated the composition at two of the sites while carbonaceous material was most abundant only at one site. The fraction unaccounted for ranged between 22 and 34%. Spatial variations of atmospheric concentrations showed significantly higher levels of minerals, some trace metals and TC at the site that was closest to the power plants. At the same site ions exhibited high correlations with minerals and the majority of trace elements.  相似文献   

18.
During the ANT VII/1 cruise of the RV Polarstern from Bremerhaven (Germany) to Rio Grande do Sul (Brazil), atmospheric particulate matter was collected by bulk filtration with a time step of 36 hours. Elemental analyses were performed in order to determine atmospheric aerosol concentrations of Al, Si, P, S, K, Ca, Ti, Mn, Fe, and Zn over the North Sea, the Channel, and the North and South Atlantic. The slight and continuous moving in latitude, associated with the large variability in concentration levels and chemical composition, allow us to point out the relative influence of the major sources of particulate matter: desert soil-dust in the tropical North Atlantic, anthropogenic emissions in the North Sea and the Channel, and biomass burning and continental biogenic activity in the tropical South Atlantic.  相似文献   

19.
The total suspended particulate (TSP) levels at Delhi (north India) were measured on 116 days between February and October 1980. The observations were stratified according to season and the values of cross-correlation of the TSP and its components were evaluated. High TSP (209 g m-3) levels were found during the summer period associated with hot and dry weather in the region and low TSP (109 g m-3) were found during the monsoon period. Most of the TSP mass was associated with natural soil elements, such as Fe, Al, Mn, Ca, and K. Only a fraction of the mass of the TSP was comprised of elements from anthropogenic sources, e.g., Pb, Ni, Cd, Sb, Cu, and Zn. The aerosols at Delhi were potentially basic in nature, unlike those in European countries which are acidic in nature and cause acid rainfall.  相似文献   

20.
电子显微镜分析北京雨雪中不可溶成分   总被引:2,自引:0,他引:2       下载免费PDF全文
张铮  朱川海 《大气科学》2003,27(2):223-235
1994~1995年的冬季和夏季,在北京大学共观测了11次不同类型的雨、雪过程,对每次降水过程进行连续取样和过滤,用电子显微镜分析全部28个降水过滤样品,测定不可溶成分中15种元素(Si、Fe、Al、K、Ca、Cu、Ti、Mg、Na、P、S、Cl、Ni、Mn、Cr)的重量百分比分布.通过平均值计算、聚类法分析和元素间的相关分析,讨论了降水中不可溶成分的物质组成和来源.  相似文献   

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