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1.
泉州城市表层土壤中金属元素来源分析 总被引：4，自引：0，他引：4
采集了泉州市47个城市表层土壤样,用ICP-MS检测技术,研究了土壤中26种重金属元素的富集特征、环境风险及污染来源。富集因子结果显示,与泉州市土壤背景值相比,Li、Ni、Co、Cu、Zn、Sr、Cd、Sn、Sb、Pb、Ta在城市表层土壤中的富集因子大于1,而Ti、V、Cr、Fe、Mn、Ga、Ge、As、Rb、Y、Nb、Cs、Bi、Th、U的富集因子小于1。从功能区上看,工业区污染最为严重,其次依次为农业区、商住区、城市绿地、交通区。环境风险指数表明,泉州市城市表层土壤中重金属污染具有极高的环境风险,达到极高风险级别的样品占48.9%。采用多元统计分析方法对土壤样品中各金属元素来源进行解析,结果表明,研究区城市表层土壤中金属元素总体可分成5类：①交通运输类（Sn、Pb、Sb、Bi）;②工业因子类（Cr、Co、Ni、Fe、Mn）;③自然因子类别（Ga、Ge、Ti、V、Cu）;④混合因子类别（Zn、Cd、Sr、Th、U、Y、As、Cs、Nb、Ta、Rb）;⑤生活垃圾因子类别（Li）。 相似文献
2.
Zhongping Yang Wenxi Lu Yuqiao Long Xinhua Bao Qingchun Yang 《Journal of Geochemical Exploration》2011
Due to the rapid urbanization and industrialization that has occurred in China over the last few decades, metals have been continuously emitted into the urban environment and now pose a serious threat to human health. Indeed, there is a growing concern over the potential for pollution of urban soils with heavy metals. Therefore, an extensive soil survey was conducted in urban areas of Changchun, China, to evaluate the current status of heavy metal contamination in soils and to evaluate its potential sources. A total of 352 samples of urban soils were collected from urban areas of Changchun using a systematic sampling strategy in which one sample per km2 was taken (0 ~ 20 cm). The levels of Cu, Pb, Zn and the major elements (Mn, Al2O3, CaO, Fe2O3, MgO, SiO2, K2O and NaO) were then determined by X-Ray fluorescence spectrometry (XRF), while the level of Cd was determined by graphite furnace atomic absorption spectrometry (GF-AAS), and the Hg and As concentrations were determined by atomic fluorescence spectroscopy (AFS). The results indicated that, when compared with the background values of topsoil in the Changchun region, the topsoil in urban areas were enriched with metals, particularly Cu, Cd, Zn, Pb and Hg. The results of correlation coefficient analysis showed that Hg, As, Cd, Cu, Pb and Zn were significantly positive correlated with each other, while Cr and Mn formed another group. Moreover, significantly positive correlations were observed between pH and Zn, Pb, Cu, Cd, As and Hg, indicating that pH influences the distributions of these metals in urban soils in Changchun. Principal component analysis (PCA) was conducted to identify sources of heavy metals and the results revealed distinctly different associations among the trace metals and the major elements in the urban soils. The concentration of Cr appeared to be controlled by the parent material (natural sources), while Cu, Pb and Zn were mainly from vehicle emissions, with Zn primarily coming from vehicle tires. Additionally, Hg and As primarily originated from coal combustion, while Cd was mainly associated with industrial sources. According to the pollution index (PI) of each metal, the overall levels of metal pollution were not especially high, but there were clearly contaminated sites concentrated in the central and northeast portion of the studied region. The Nemerow integrated pollution index (NIPI) of the seven metals also indicated that urban soils in Changchun city were classified as having low level of pollution. 相似文献
3.
Spatial distribution and contamination assessment of heavy metals in urban topsoil from inside the Xi’an second ringroad, NW China 总被引：1，自引：1，他引：0
The paper reports the spatial distribution and contamination level of heavy metals (Co, Cr, Cu, Mn, Ni, Pb, Zn and V) in urban topsoil from the interior area of the second ringroad of Xi’an city, China, based on X-ray fluorescence spectroscopy measurements. Geostatistical analysis shows that Co, Cu, and Pb have similar spatial distribution patterns. Heavy traffic density mainly contributed to the high concentrations of Co, Cu and Pb. The spatial distribution of Cr coincides with the industrial activity, whereas the spatial distribution of Zn differs from other heavy metals. The high concentrations of Zn coincide with heavy traffic and high population density. For Mn, Ni and V, natural factors are important in controlling their distribution. The calculated geoaccumulation indices indicate that urban topsoil inside the Xi’an second ringroad was uncontaminated by Cr, V, Mn and Ni, while Pb, Cu, Co and Zn are classified as uncontaminated to moderately contaminated with means of 0.64, 0.46, 0.26 and 0.21, respectively. The Nemero synthesis pollution index of these heavy metals revealed that the topsoil inside Xi’an second ringroad has been heavily contaminated due to anthropogenic activity. 相似文献
4.
Wojciech Zgłobicki Małgorzata Telecka Sebastian Skupiński Aneta Pasierbińska Marcin Kozieł 《Environmental Earth Sciences》2018,77(23):774
Heavy metals are constantly emitted into the environment and pose a major threat to human health, particularly in urban areas. The threat is linked to the presence of Cd, Cr, Cu, Ni, Pb, and Zn in street dust, which consists of mineral and organic particles originating from the soil, industrial emitters, motor vehicles, and fuel consumption. The study objective was to determine the level of street dust contamination with trace metals in Lublin and to indicate their potential sources of origin. The analyses were carried out with an energy-dispersive X-ray fluorescence spectrometer. The sampling sites (49) were located within the city streets characterised by varying intensity of motor traffic. The following mean content values and their variation (SD) were determined: Cd: 5.1?±?1.7 mg kg?1, Cr: 86.4?±?23.3 mg kg?1, Cu: 81.6?±?69.2 mg kg?1, Ni: 16.5?±?3.9 mg kg?1, Pb: 44.1?±?16.4 mg kg?1, and Zn: 241.1?±?94.6 mg kg?1. The level of pollution was assessed with several widely used geochemical indices (geoaccumulation index, enrichment factor, pollution index, index of ecological risk, and potential ecological risk index). For most of the indices, the mean (median) values are arranged in the following manner: Zn?>?Cu(or Cd)?>?Pb?>?Ni?>?Cr. In general, street dust in Lublin does not show pollution with Cr, Ni, and Pb. Igeo and EF indices show moderate levels for Cu, Cd, and Zn; their presence in street dust is linked with anthropogenic factors (motor traffic). A significant threat is posed by Cd, and more than half of the samples show considerable pollution with cadmium (median for the index of ecological risk: 151). The spatial pattern of indices and the results of statistical analyses (CA, PCA) indicate three groups of elements: (1) Cr and Ni: natural origin; (2) Pb: mixed origin; and (3) Cd, Cu, and Zn: anthropogenic origin (mainly motor vehicle traffic). Higher content values for metals of anthropogenic origin in street dust indicate that it is a source of pollution of soil and air in the city. 相似文献
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6.
在济南市城区对大气降尘及不同污染端元样品进行采集,系统分析了大气降尘和污染端元元素含量特征,并对大气降尘空间分布及污染来源进行研究。结果表明:不同污染端元中元素含量差别明显,燃煤尘中As、Cd、F、Pb是汽车尾气尘的3倍以上,是交通尘、冶炼尘、建筑尘等其他端元尘的1.26~2.35倍,对环境影响较大;汽车尾气尘中Cr、Ni、S、Zn含量最高,冶炼尘中Co、Ni、Pb、F含量偏高,而建筑尘中多数元素含量为所有端元尘中最低。与土壤背景值相比,济南市大气降尘中Cr、Cu、Pb、Zn、Cd、F、S富集程度较高,受到不同程度人为污染;相关分析和因子分析结果表明,Cd、Cu、Hg、Pb、As主要来源于企业燃煤,大气降尘中这些元素高含量区与热电厂、冶炼厂、化工厂等燃煤污染源空间分布相一致;F、S可能与汽车尾气排放有关,而As、Cr主源于交通污染,这3种污染源是济南市大气降尘污染的主要来源,对降尘的贡献约占60.42%。研究表明,工业燃煤排放已逐渐代替汽车尾气成为大气降尘中Pb元素的主要来源。 相似文献
7.
Dongguan (东莞) City, located in the Pearl River Delta, South China, is famous for its rapid industrialization in the past 30 years. A total of 90 topsoil samples have been collected from agricultural fields, including vegetable and orchard soils in the city, and eight heavy metals (As, Cu, Cd,Cr, Hg, Ni, Pb, and Zn) and other items (pH values and organic matter) have been analyzed, to evaluate the influence of anthropie activities on the environmental quality of agricultural soils and to identify the spatial distribution of trace elements and possible sources of trace elements. The elements Hg, Pb, and Cd have accumulated remarkably here, incomparison with the soil background content of elements in Guangdong (广东) Province. Pollution is more serious in the western plain and the central region, which are heavily distributed with industries and rivers. Multivariate and geostatistical methods have been applied to differentiate the influences of natural processes and human activities on the pollution of heavy metals in topsoils in the study area. The results of cluster analysis (CA) and factor analysis (FA) show that Ni, Cr, Cu, Zn, and As are grouped in factor F1,Pb in F2, and Cd and Hg in F3, respectively. The spatial pattern of the three factors may be well demonstrated by geostatistical analysis. It is shown that the first factor could be considered as a natural source controlled by parent rocks. The second factor could be referred to as "industrial and traffic pollution sources". The source of the third factor is mainly controlled by long-term anthropic activities ,ad a consequence of agricultural fossil fuel consumption and atmospheric deposition. 相似文献
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A total of 31 topsoil samples were systematically collected from the Panzhihuaminingarea including steel smelting,coal mining ,urban and rural districts.A normalization procedure was adopted to establish the environmental geochemical baseline models for this area.By using the above baseline models,the regional geochemical baseline values of As,Cr,Cu,Ni,Pb and Zn were determined.On the basis of the baselines,the enrichment factors were used to analyze the mechanism of trace metal pollution in topsoil from anthropogenic sources,and the results showed that the serious trace metal pollution is caused by human activities in coal mine,iron mine,smelting factory,tailing dam and other industrial districts in the Panzhihua area. 相似文献
10.
Correlation between magnetic susceptibility and heavy metals in urban topsoil: a case study from the city of Xuzhou, China 总被引：7，自引：0，他引：7
Anthropogenic influence, mainly due to urban and industrial activities and traffic exhaust, may affect urban topsoil via atmospheric contamination and solid waste. Magnetic susceptibility measurements were conducted on 21 urban topsoil samples from the city of Xuzhou, China. High intensities of magnetic susceptibility were detected in the majority of the samples. SEM analysis shows that magnetic minerals are in the form of spherules and mainly due to anthropogenic inputs. The heavy metals Pb, Cu, Zn, Se, Sc, Mo, Fe, and Bi show strong correlations with magnetic susceptibility, and Ag, Ba, Cd, Ni, Cr, Sb, and Sn, on the other hand, show a weak correlation with magnetic susceptibility. Whereas, of these metals studied, only Hg has no significant correlation with the susceptibility. The Tomlinson pollution load index (PLI) also shows significant correlation with the susceptibility (χ). The present study shows that magnetic susceptibility is a fast, inexpensive, and non-destructive method for the detection and mapping of contaminated soils. 相似文献
11.
《Applied Geochemistry》2001,16(11-12):1361-1368
Due to rapid urbanisation and scarcity of land, most of the urban parks and recreational areas in Hong Kong are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. An extensive soil survey was conducted in urban parks of Hong Kong to study the current conditions of heavy metals contamination in soils. Soil samples and associated street dusts were collected from more than 60 parks and public amenity areas in old urban districts, industrial areas and New Towns of the territory. Soils were also sampled in the remote country parks to establish the baseline conditions. The total concentrations of heavy metals and major elements in the samples were determined. The results indicate that urban soils in Hong Kong have elevated concentrations of Cd, Cu, Pb and Zn. The parks with high metal concentrations are located in old urban commercial districts and industrial areas, indicating that the major contamination sources in these soils are traffic emissions and industrial activities. In addition, the application of Cd containing phosphate fertilizers may be an important source of Cd in urban park soils. The street dusts have highly elevated Zn concentration, particularly along the main trunk roads. The high Zn content in the street dusts may come from traffic sources, especially vehicle tyres. Selective soil and road dust samples were also analysed for potential chemical speciation by a sequential chemical extraction method. The chemical partitioning results show that Pb and Zn are mainly in the carbonate/adsorbed and Fe–Mn oxide phases, while Cu is largely associated with the organic and sulphide fractions. The high exchangeable Cd in urban soils and high concentration of Zn in street dusts need further investigation for their ecological and health implications. 相似文献
12.
Jurate Kumpiene Evelina Brännvall Ričardas Taraškevičius Česlovas Aksamitauskas Rimantė Zinkutė 《Journal of Geochemical Exploration》2011
An investigation of the spatial variability of topsoil contamination level was performed in 49 preschool playgrounds located in Vilnius city and correlated with urban (height and age of the preschools and height of surrounding buildings) and natural (altitude) factors. Composite samples, consisting of 20–30 sub-samples, were collected from 10 cm topsoil layer with a 3–5 m distance from each other. Sieved fraction (< 0.63 mm) was ashed at 400 °C, ground to < 1.0 μm and analysed for the real total concentrations of 22 trace elements (Ag, B, Ba, Co, Cr, Cu, Ga, Li, Mn, Mo, Nb, Ni, Pb, Sc, Sn, Sr, Ti, V, Y, Yb, Zn and Zr) using optical atomic emission spectrophotometry. Information on construction year and height (number of building stories) of preschool and surrounding buildings was acquired from the Centre of Registers of Lithuania. Out of 22 analysed elements, 13 to a greater extent exceeded the background values in several areas and were used to calculate the total contamination index (Zs13). Out of 49 analysed areas, 21 had moderately hazardous to hazardous levels of contamination as indicated by Zs13. The main contaminating elements, exceeding the permissible concentrations were Ag, Cu, Mo, Pb, Sn and Zn, the origins of which coincide with city industry and traffic. Topsoil around the newer preschool buildings, despite their location, contained lower concentrations of contaminants, while areas at higher altitudes were more contaminated than those located at lower altitudes. The latter causality is biased, as the city industry, and hence the highest contamination, is in districts located higher above sea level than the remaining studied sites. 相似文献
13.
Geochemical studies on urban soil from two sampling depths in Tampere Central Region,Finland 总被引：1，自引：0，他引：1
Preliminary geochemical mapping was carried out within urban areas in Tampere Central Region, Finland, to gain a better understanding of element concentrations in urban soil and to provide information on baselines in soil within urban centres for soil contamination assessment purposes. The soil samples were taken from central city parks, day-care centres and school yards, and residential areas. Various sampling depths have generally been used in urban geochemical surveys. The aim of this study was to compare the results from two commonly used sample types taken from the same sites in urban soil: single samples of minerogenic topsoil from the 0–25 cm layer and composite samples of minerogenic topsoil from a depth of 0–2 cm. The concentrations of most of the studied trace elements showed a significant correlation between samples from 0 to 2 and 0 to 25 cm, but element concentrations differed between the two studied sample depths. For most of the studied elements, the median concentrations were higher in the 0–25 cm samples, but anomalous concentrations were more often found in the 0–2 cm samples. Some elements had elevated concentrations when compared with the Finnish guideline values for soil contamination assessment. This study did not conclusively establish whether a sampling depth of 0–2 or 0–25 cm should be recommended for similar studies in the future. Selection of the sampling depth in geochemical studies greatly depends on the aim of the project. In order to determine the upper limits of geochemical baseline variation, the deeper sampling depth appears to be more feasible. However, for the preliminary health risk assessment of areas with sensitive land uses, e.g. children’s playgrounds, samples from 0–2 cm depth are considered informative. Such samples may also be used to indicate local sources of dusting creating site-specific hotspots of potentially harmful elements in urban topsoil. 相似文献
14.
S. Singh P. Bhattacharya N. C. Gupta 《International Journal of Environmental Science and Technology》2018,15(5):1061-1072
The present work is an attempt to investigate pollution effect on an ornamental tree species Thevetia peruviana (Pers.) K. Schum. The study was conducted in various green spaces of institutional, industrial, residential and near traffic site representing as different status of air pollution concentration depending on land-use type. The resistance index calculated for selected species had mean value of 14.57 ± 0.41 observed at study sites. The dust deposition was found in range of 5.14–7.74 mg cm?2 on foliar surface of 12 cm2. The examination of leaf structure with scanning electron microscope showed presence of airborne dust particles in coarse and fine sizes with higher deposition found in industrial and residential sites. The epicuticular wax layer on upper surface of foliar was found eroded at industrial and traffic regions. The equivalent diameter of particles was observed to range from 0.45 to 12.71 µm in Poisson distributional pattern. The density of number concentration of dust particles was observed 1411 and 3703 in institutional and industrial area deposited on 0.22 mm2 of foliar surface. The elemental distribution on leaves of Thevetia peruviana has revealed a mixture of carbonaceous and soil matrix elements such as C, O, Al, Na, Si, K and Mg observed in proportion of X-rays counts per second. The whole experiment gave a positive indication for plant species as a tolerant bio-indicator of air pollutants in Delhi. The diverse flora present in city provides an opportunity for reducing harmful concentration of PM10 and PM2.5 and improving quality of air for human health. 相似文献
15.
Contamination,chemical speciation and vertical distribution of heavy metals in soils of an old and large industrial zone in Northeast China 总被引：5，自引：0，他引：5
Fayun Li Zhiping Fan Pengfei Xiao Kokyo Oh Xiping Ma Wei Hou 《Environmental Geology》2009,57(8):1815-1823
Heavy metal pollution of soils has become a major concern in China as a consequence of rapid urbanization and industrialization
in recent years. However, the evaluation on soil heavy metal pollution in Shenyang, the largest heavy industrial base city
in China, has not yet been conducted. In this study, accumulation, chemical speciation, and vertical distribution Cu, Zn,
Pb and Cd in soils were studied and pollution condition was assessed in Tiexi Industrial District of Shenyang, the largest
and oldest industrial zone in Northeastern China. The results showed that in topsoil, the average concentration of total Cu,
Zn, Pb, and Cd was 209.06, 599.92, 470.19 and 8.59 mg kg−1, respectively, much higher than the national threshold limit. The values of pollution index and integrated pollution index
showed that the pollution level was Cd > Cu > Zn > Pb, and Cd, Cu and Zn belong to heavy pollution level. The residual, Fe
and Mn oxide-bound, and organic-bound species accounted for about 90%, while carbonate-bound and exchangeable species accounted
for about 10%. This study indicates that the soils in the industrial zone were widely and extremely polluted by multi-heavy
metals as a result of long-term industrial activities. 相似文献
16.
以淄博城市土壤为研究对象,应用统计学方法对土壤地球化学特征进行研究,采用单因子指数和尼梅罗综合指数法对土壤环境质量进行评价,同时采用Hakanson提出的潜在生态危害指数法对土壤重金属的潜在生态危害进行评价,并对其产生的生态环境效应进行研究。结果表明:Hg、Cd、S、Pb、Se、Org C等元素或指标在表层土壤中的含量明显大于深层,二者间相关性较差,且表层土壤存在明显碱化特征,受到不同程度人为活动影响;单因子评价Cd、Cu、Hg、Ni、Zn都出现污染,其中Cd污染面积最大,达到5.11%,综合污染评价土壤环境质量整体良好,污染土壤占9.84%,其形成可能与工业生产和人类活动有关;潜在生态危害程度最强的重金属是Hg、Cd,局部地段已经达到强、极强潜在生态危害水平,综合重金属潜在生态危害水平整体表现为中等,其轻微、中等、强、很强生态危害的比例分别为29.32%、55.02%、12.85%、2.81%,从空间分布上来看,强、很强潜在生态危害区分布与各类工业空间布局相吻合,种植的蔬菜中Cd、Pb、Zn、Hg等重金属有不同程度超标现象,需加强对土壤及农产品进行协同监测与评价,防止土壤重金属污染加重影响人体健康。 相似文献
17.
Assessment of heavy metal pollution in urban topsoils from the metropolitan area of Mexico City 总被引：2，自引：0，他引：2
O. Morton-Bermea E. Hernández-Álvarez G. González-Hernández F. Romero R. Lozano L.E. Beramendi-Orosco 《Journal of Geochemical Exploration》2009
This study reports the degree of heavy metal pollution (Cr, Cu, Ni, Pb, Zn and V) in 135 urban topsoil samples from the metropolitan area of Mexico City. Pollution indices (PI) were calculated to identify the metal accumulation with respect to the background values. The levels of heavy metals in the analyzed samples show a wide range of variation. Lead, Zn and Cu are the elements most enriched in the analyzed area, presenting pollution indexes of up to 23.8, 21.6 and 12.4, respectively. Geochemical maps were produced to assess the spatial distribution of pollution index. It is concluded that emissions from vehicles may be the major source of Pb urban contamination; furthermore, other small or large factories are possible sources for soil pollution (Cu, Zn). The concentration of Cr, Ni, and V in most of the analyzed samples do not appear to reach pollution levels. The assessment of the soil environmental quality in the metropolitan area Mexico City in terms of PI can be used as the basis for a regular monitoring program for implementing suitable pollution control measures. 相似文献
18.
This study assesses the origin and pollution of trace metals in surface soils in a region with contrasting land uses (urban
vs. rural). Principal component analysis (PCA) reveals that Cr and Ni are predominantly of geogenic origin. These two trace
metals are also the only ones with statistically significant correlations with soil particle size and organic matter content.
Copper, Pb and Zn, and possibly Hg, are of anthropogenic origin, but their concentrations rarely reach levels described as
strongly polluted by pollution indexes. The concentrations of these anthropogenic trace metals are statistically not different
in urban and rural areas, except for Pb that is higher in the urban area. This general lack of a difference between the two
land uses indicates that the influence of this small urban area on trace metal concentrations in soils is minor. Lead and
Zn have the most, but still a modest number, of strongly polluted sites, mainly in an industrial part of the city. GIS analysis
shows that, based on the pollution load index (PLI), overall concentrations of trace metals also reach their highest levels
in that industrial area. These observations indicate that the influence of industry on trace metal pollution in soil exceeds
that of other urban activities in the region. Local background concentrations were found to be very different from general
crustal background concentrations. This demonstrates the importance of the careful selection of a background type in studies
like this. 相似文献
19.
城市环境地球化学研究综述 总被引：20，自引：0，他引：20
近年来地球科学越来越多地面向城市,城市环境受到人类活动的广泛影响,自然及人类活动引起的城市地球化学问题日益受到人们的重视。城市环境地球化学是应用地球化学的原理和方法研究城市生态环境问题,主要研究城市土壤、沉积物、尘埃、地表水、地下水、生物、空气等介质中化学元素及同位素的分布、演化、环境作用及健康效应,重点解决城市地球化学环境质量变化的原理及由此产生的生态环境效应及人体健康效应。城市环境地球化学的主要研究对象是传统工业城市、典型矿业城市及国际化的大都市。在城市地球化学概念出现之后短短的10余年时间内,很多国家开展了城市环境地球化学调查和研究工作,取得了重要的成果和进展,并发展成为环境地球化学与城市环境的重要方向,但仍存在着一定的问题,需要深入研究。目前,城市环境系统的地球化学填图、城市地球化学与环境污染研究、城市地球化学与生态风险研究、城市地球化学与人体健康研究、城市地球化学系统的调控与环境规划等领域是国际城市环境地球化学的热点和前沿。 相似文献
20.
R. Fatemitalab M. Zare S. Kardar 《International Journal of Environmental Science and Technology》2016,13(5):1229-1234
Heavy metals toxicity is a significant problem for ecological, evolutionary, nutritional and environmental reasons. This study was carried out to evaluate the amount of cadmium, zinc and lead absorption in leaf and root of pine, cypress, plantain and ash in Isfahan, Iran, in 2013. For this purpose, three heavy metals (Cd, Pb and Zn) and three sites (heavy traffic, moderate traffic and control) were chosen based on their effects on human health. The results indicated that the highest and lowest lead and cadmium concentrations belonged to heavy traffic site and control site, respectively. Cd in leaf versus Pb in leaf and Cd in root versus Pb in root had the highest correlation coefficient among the traits indicating positive influence of leaf and root on absorbing Cd and Pb from soil, water and air. In all the studied species, the concentration of Pb was higher than that of Cd and Zn. This was certainty due to the vehicle traffic emitting much more lead than cadmium and zinc. In all the studied species, metal concentration in leaves was higher than in roots, which may be due to high concentration of heavy metals in air than in soil. In this study, Pinus eldarica Medw. tree was found to be the best species to monitor polluted sites in Isfahan city. 相似文献