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1.
An investigation on spatial distribution, possible pollution sources, and affecting factors of heavy metals in the urban–suburban
soils of Lishui city (China) was conducted using geographic information system (GIS) technique and multivariate statistics.
The results indicated that the topsoils in urban and suburban areas were enriched with metals, such as Cd, Cu, Pb, and Zn.
Spatial distribution maps of heavy metal contents, based on geostatistical analysis and GIS mapping, indicated that Cd, Cr,
Cu, Mn, Ni, Pb, and Zn had similar patterns of spatial distribution. Their hot-spot areas were mainly concentrated in the
densely populated old urban area of the city. Multivariate statistical analysis (correlation analysis, principal component
analysis, and clustering analysis) showed distinctly different associations among the studied metals, suggesting that Cr,
Cu, Ni, Pb, Cd, and Zn had anthropogenic sources, whereas Co and V were associated with parent materials and therefore had
natural sources. The Cd, Cr, Ni, Pb, and Zn contents were positively correlated with soil organic matter, pH, and sand content
(p < 0.01). It is concluded that GIS and multivariate statistical methods can be used to identify hot-spot areas and potential
sources of heavy metals, and assess soil environment quality in urban–suburban areas. 相似文献
2.
B. Shifteh Some’e F. Hassanpour A. Ezani S. R. Miremadi H. Tabari 《Environmental Earth Sciences》2011,64(7):1849-1864
Analysis of the spatial variability of soil properties is important to explain the site-specific ecosystems. Spatial patterns
of some soil properties such as soil texture, exchangeable sodium percentage (ESP), electrical conductivity (ECe), soil pH
and cation exchange capacity (CEC) were analyzed in salt and sodic affected soils in the south of the Ardabil province, in
the northwest of Iran, to identify their spatial distribution for performance of a site-specific management. Soil samples
were collected from 0 to 30, 30 to 60, 60 to 90, 90 to 120 and 120 to 150 cm soil depths at sampling sites. Data were investigated
both statistically and geostatistically on the basis of the semivariogram. The spatial distribution model and spatial dependence
level varied in the study area. Among the considered parameters, maximum and minimum spatial variability were observed in
EC and pH parameters, respectively. Soil properties showed moderate to strong spatial dependence, except for a few. ECe was
strongly spatially dependent in the total soil depth and clay was strongly spatially dependent at the first depth. Sand and
pH were moderately spatially dependent for three of the five depths. ESP was strongly spatially dependent and silt was moderate
in the total soil depths, except at 90–120 cm depth. Furthermore, CEC had strong spatial dependence for three of the five
depths. All geostatistical range values were >1,389 m in this study. It was concluded that the strong spatial dependency of
soil properties would lead to extrinsic factors such as bedrock, agricultural pollution, drainage and ground water level. 相似文献
3.
Environment impact of heavy metals on urban soil in the vicinity of industrial area of Baoji city,P.R. China 总被引:3,自引:0,他引:3
Heavy metals in soils are of great environmental concern, in order to evaluate heavy metal contents and their relationships
in the surface soil of industrial area of Baoji city, and also to investigate their influence on the soils. Soil samples were
collected from 50 sites, and the concentration of Pb, Zn, Cu, Cr, Ni heavy metals and the contents of characteristics in soil
from industrial area of Baoji city were determined with X-ray fluorescence method. The concentrations of Pb, Zn, Cu, Cr and
Ni in the investigated soils reached the amount of 2,682.00–76,979.42, 169.30–8,288.58, 62.24–242.36, 91.96–110.54 and 36.14–179.28 mg kg−1, respectively. The major element Pb contents of the topsoils were determined. to highlight the influence of ‘anthropic’ features
on the heavy metal concentrations and their distributions. To compare, all values of elements were much higher than those
of unpolluted soils in the middle of Shaanxi province that average 16.0–26.5, 67.1–120.0, 17.8–57.0, 46.9–65.6 and 24.7–34.6 mg kg−1 for Pb, Zn, Cu, Cr and Ni, respectively. An ensemble of basic and relativity analysis was performed to reduce the precipitate
of Pb in soil was extremely high and greatly relativity with other elements. Meanwhile, Pb, Zn, Cu, Cr, Ni heavy metals were
typical elements of anthropic activities sources, so it was easy to infer to the tracers of anthropic pollutions from the
factorial analysis, which was coming from the storage battery manufactory pollutions. The pollutant distributions were constructed
for the urban area which identified storage battery manufactory soot precipitate as the main source of diffuse pollution and
also showed the contribution of the topsoils of industrial area of Baoji city as the source point of pollution. Consequently,
the impact of heavy metals on soil was proposed and discussed. These results highlight the need for instituting a systematic
and continuous monitoring of heavy metals and other forms of pollutants in Baoji city to ensure that pollution does not become
a serious problem in the future. 相似文献
4.
A soil geochemical survey was undertaken in the cultivated region of Agia in Thessaly area, Central Greece. The objectives
of the study were to assess the levels of soil contamination in respect to average concentrations of toxic metals in the region,
to determine the associations between the different toxic elements and their spatial distribution and to identify possible
sources of contamination that can explain the spatial patterns of soil pollution in the area. One hundred seventy three soil
samples were collected and analysed by ICP-AES after digestion with a mixture of HClO4–HNO3–H2O. The study focused on eleven elements (Cu, Pb, Zn, Ni, Co, Mn, As, V, Cr, Fe and Mg) and all of them except Pb have mean
concentrations above the average global soil composition. The elements Ni, Cr, Mn and V show concentrations that according
to G.L.C guidelines the Agia soils are classified as slightly contaminated to contaminated. Factor analysis explained 84.02%
of the total variance of the data through four factors. Combined with spatial interpretation of its output, the method successfully
grouped the elements according to their sources and provided evidence about their natural or anthropogenic origin. 相似文献
5.
6.
Spatial variability of soil moisture at typical alpine meadow and steppe sites in the Qinghai-Tibetan Plateau permafrost region 总被引:2,自引:1,他引:1
Zhaoping Yang Hua Ouyang Xianzhou Zhang Xingliang Xu Caiping Zhou Wenbin Yang 《Environmental Earth Sciences》2011,63(3):477-488
Permafrost degradation has the potential to significantly change soil moisture. The objective of this study was to assess
the variability of soil moisture in a permafrost region using geostatistical techniques. The experiment was conducted in August
2008 in alpine steppe and meadow located in the Qinghai-Tibetan Plateau permafrost region. Four soil depths (0–10, 10–20,
20–30 and 30–40 cm) were analyzed using frequency domain reflectometry, and sampling made of 80 points in a 10 m × 10 m grid
were sampled. Soil moisture was analyzed using classical statistics to appropriately describe central tendency and dispersion,
and then using geostatistics to describe spatial variability. Classical statistical method indicated that soil moisture in
the permafrost region had a normal distribution pattern. Mean surface soil moisture in alpine meadow was higher than that
in alpine steppe. The semivariograms showed that soil moisture variability in alpine cold steppe was larger than that in alpine
meadow, which decreased with depths. Nugget values in alpine steppe were low (0.1–4.5), in contrast to alpine cold meadow.
Soil moisture in alpine steppe had highly structured spatial variability with more than 93.4% spatial heterogeneity, and the
range decreased with depth. Soil moisture content in alpine cold meadow had a moderate spatial dependence with a range of
51.3–169.2 m, increasing with depth. 相似文献
7.
F. Nannoni R. Mazzeo R. Santolini G. Protano 《International Journal of Environmental Science and Technology》2017,14(12):2591-2602
Multi-matrix environmental monitoring was used to evaluate the influence of a municipal solid waste landfill (Ginestreto, Emilia Romagna, Italy) on the level and distribution of heavy elements in the surrounding environment (air, soil and soil biota). Concentrations of As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, Tl and Zn were measured by inductively coupled plasma-mass spectrometry in transplanted lichens, topsoils and isopods. The highest accumulation levels found for Cd, Cr, Pb, Sb and Zn in lichens transplanted within the Ginestreto landfill. However, similar concentrations of these heavy elements were also found in lichens exposed in monitoring sites influenced by other man-made sources, such as vehicle traffic and truck movements. The fallout of heavy elements emitted by the landfill had low impact on their levels in topsoil: Cd, Cr, Pb, Sb and Zn showed higher contents in topsoil collected close to the landfill and a slight decrease in concentrations with increasing distance from the landfill. There was no variation in heavy element accumulation in isopods in relation to distance from the landfill. The results of this study indicate that the Ginestreto municipal solid waste landfill had limited impact on the environmental distribution of heavy elements, since accumulation and enrichment in lichens and topsoils were only detected close to the landfill, up to about 100 m from its border. 相似文献
8.
The probability features of non-normality and non-lognormality are widely observed in geochemistry due to the influences of multiple factors that are difficult to quantify and model. In Northern Ireland, the pseudo-total concentrations of 14 elements (Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb and Zn) from 6138 topsoils were measured, and GIS mapping showed that the spatial distribution of these data were in line with the spatial distribution of geology in the area. Investigations into the influences of geology on the concentration data and their probability features were carried out using GIS and statistics in this study. The whole raw data sets for each element were positively skewed and none of them followed either normal or lognormal distributions. Logarithmic transformation was found to have “over-transformed” most of the data sets, changing their skewness from positive to negative values. When soil samples were classified by rock type using a GIS overlay function, obvious differences were observed in the chemical concentrations of soils derived from different rock types. Soils in basalt areas displayed the highest concentrations for most elements under study (Ca, Co, Cr, Cu, Fe, Mg, Mn, Na, Ni, P and Zn) but the lowest concentrations for K, while the highest levels for Cd and Pb occurred in the shale areas. Classifying soils by rock type produced more normally distributed data sets, especially for the igneous rock areas. To restrain the influence of soil type and land cover, samples from both gleys and pastures were extracted via a GIS and it was found the data sets then showed generally greater tendencies towards normality. However, many of the data sets would still not pass a test for normality unless the sample size was small (e.g. of the order of a couple of hundreds). Geology, soil type, land cover and sample size all played important roles in determining soil chemical concentrations and their probability features. However, the influences from other factors were still evident. Attempts made in this study show that it remains a challenging task in geochemistry to separate all the factors and to model their influence at the regional scale. 相似文献
9.
The marine coastal sediments from Togo have been analysed for the trace elements Cd, Cr, Cu, Ni, Pb, Sr, V, Zn and Zr to
ascertain the geo-ecological impact of dumping of phosphorite tailings into the sea. Trace element concentrations ranged from
2–44 ppm for Cd, 22–184 ppm for Cu, 19–281 ppm for Ni, 22–176 ppm for Pb, 179–643 ppm for Sr, 38–329 ppm for V, 60–632 ppm
for Zn and 18–8928 ppm for Zr. Regional distribution of trace elements in the marine environment indicates that the concentrations
of Cr, Cu, Ni, Pb, V, Sr and Zn increase seawards and along the coastal line outwards of the tailing outfall, whereas Cd and
Zr showed reversed spatial patterns. Sorting and transport of phosphorite particles by coastal currents are the main factors
controlling the distribution of particle-bound trace metals in the coastal environment. The Cd, Sr and Zn concentrations decrease
with decreasing grain size in marine coastal sediments, whereas Cr, Cu, Ni and Zn concentrations increase with decreasing
grain size. Percolation and shaking experiments were carried out in laboratory using raw phosphate material and artificial
sea water. Enhanced mobilization of Cd from phosphorites by contact with the sea water was observed.
Received: 11 May 1998 · Accepted: 20 October 1998 相似文献
10.
为研究青岛城区土壤的环境地球化学特征,对青岛市南区、市北区、四方区、李沧区、崂山区5区进行了广泛的土壤地质调查。在每1km2一个样品的取样密度下取得表层土样(0~10cm深度)319个,经前期处理后,利用多种仪器如X射线荧光光谱(XRF)、等离子体发射光谱(ICP-OES)和等离子体质谱(ICP-MS)等分析测得所有样品的72种元素的含量,本文探讨了重金属元素Cd、Cr、Cu、Ni、Pb和Zn及类金属元素As的含量分布。结果表明,人类活动导致表层土壤中元素Cd、Cu、Pb和Zn含量的增加,而元素As、Cr和Ni主要是地质起源,但也会受到人类活动的影响。其中Zn的含量值变化较大,Zn元素含量值增高的地区是工业、交通密集处等人类活动频繁的地区。 相似文献
11.
María Teresa Rodríguez-Salazar Ofelia Morton-Bermea Elizabeth Hernández-Álvarez Rufino Lozano Victor Tapia-Cruz 《Environmental Earth Sciences》2011,62(5):899-905
This research presents and discusses information concerning the spatial distribution of heavy metals (Pb, Cu, Zn, Ba, Co,
Cr, Ni and V) in the urban environments of Mexico City using geographical information system and statistical analysis. Superficial
soil samples (n = 146) were analyzed. The highest contamination indices were found in the north and center zone of the metropolitan area.
In contrast, the surrounding rural fields show a lower impact grade. The higher concentrations of Pb, Cu, Zn and Ba were observed
as being related to high vehicular traffic, nevertheless other elements such as Co, Cr, Ni and V do not show anthropogenic
influence and their content can be attributed to the parental rock. The results are compared with previous surveys carried
out in 2003 in order to evaluate temporal deposition trends. No changes were found on reported concentrations except for Cu
and Zn, whose concentration has increased in later years. The results suggest that spatial distribution analysis and results
in comparison with previous studies could be useful for the management and sustainable development of the metropolitan area
of Mexico City. 相似文献
12.
Two types of soil (fluvisols and anthrosols) were collected from different environmental settings (suburb and industrial area)
in Wuhan, central China, aiming to examine the applicability of magnetic mapping for heavy metal pollution of urban soil in
a large region. Magnetic measurements and chemical analysis indicated elevated magnetization and heavy metal concentrations
of topsoils in the industrial area. Magnetic susceptibility (χ), anhysteretic remanent magnetization (ARM) and saturation
isothermal remanent magnetization (SIRM) of fluvisols are much higher than those of anthrosols, but contrary for frequency-dependent
susceptibility, indicating that soil magnetism strongly depends on the soil type/condition. Predominant magnetic carrier in
topsoils in industrial area is pseudo-single-domain/multi-domain magnetite. Environmental scanning electron microscope/energy
dispersive X-ray examination of the magnetic extracts from these topsoils revealed abundant spherical particles with diameters
of 10–50 μm that are rich in iron-oxides, and could be attributed to the nearby industrial activities (e.g., steel work and
power generation). Significant correlations were observed between magnetic concentration-related parameters (e.g., χ, ARM
and SIRM) and concentrations of Cu, Pb, Zn, Hg and Tomlinson pollution load index. These results proposed that magnetic proxy
mapping of soil pollution is an effective, fast and inexpensive tool for delineation of heavy metal pollution. However, interpretation
of magnetic properties for such a purpose must be done on a site-specific basis, taking into account the possibilities of
pedogenic enhancement/depletion under the specific soil conditions. 相似文献
13.
Heavy metal concentrations and their possible sources in paddy soils of a modern agricultural zone,southeastern China 总被引:5,自引:0,他引:5
In a typical modern agricultural Zone of southeastern China, Haining City, 224 topsoil samples were collected from paddy fields
to measure the total concentrations of copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr), mercury (Hg), arsenic
(As) and cobalt (Co). The total concentrations ranged from 15.30 to 78.40 mg kg−1 for Cu, 20.10 to 41.40 mg kg−1 for Pb, 54.98 to 224.4 mg kg−1 for Zn, 0.04 to 0.24 mg kg−1 for Cd, 54.90 to 197.1 mg kg−1 for Cr, 0.03 to 0.61 mg kg−1 for Hg, 3.44 to 15.28 mg kg−1 for As, and 7.17 to 19.00 mg kg−1 for Co. Chemometric techniques and geostatistics were utilized to quantify their spatial characteristics and define their
possible sources. All eight metals had a moderate spatial dependency except that Pb had a strong spatial dependency. Both
factor analysis and cluster analysis successfully classified the eight metals into three groups or subgroups, the first group
included Cu, Zn and Cr, the second group included Cd, As and Co, and the last group included Pb and Hg. The Cu, Zn and Cr
concentrations in majority samples were higher than their local background concentrations and they were highly correlated
(r > 0.80), indicating that they had similar pollution source and anthropic factor controlled their spatial distribution; the
Cd, As and Co concentrations in majority samples were lower than their local background concentrations, indicating that the
source of these elements was mainly controlled by natural factors; the mean concentration of Pb exhibited generally low level,
close to its local background concentration, the Hg concentration in about half of samples was higher than its local background
concentration, and they were poor correlated with the other metals, indicating that the source of Pb and Hg was common controlled
by natural factor and anthropic factor. 相似文献
14.
Geostatistical analysis of selected soil properties were performed in two mangrove sites (B7 and B9) dominated by the mangrove
speciesRhizophora mangle along the San Juan River, Venezuela, to evaluate the effect of forest disturbance on nutrient spatial distributions. Plots
within area B7 were clear-cut in 1972–1973 and in area B9 in 1982–1983. Four plots within each area were systematically selected
and represented natural (2) and regenerated (2) forests. Individual plots were 1.5 ha in B7 and 1.25 ha in B9 and sampled
at a resolution of 25 m. Soil samples were obtained at the intersection of an aligned grid with 90 points in B7 and 78 points
in B9. Measured soil properties included salinity, total nitrogen, total carbon, total phosphorus, osmolality, and pore water
cation concentrations (potassium, calcium, magnesium, and sodium). Sites were sampled in May 1996 and 1997, although spatial
analysis was performed only for the data obtained in May 1997. Geostatistical analysis showed that most of the variables tested
were spatially auto-correlated within each area and that there were no differences between regenerated and natural plots.
Structural variance as a proportion of sample variance ranged from 55–99% for most of the properties. The significant spatial
dependence observed for most of the variables in natural and regenerated plots, despite management schedules, indicates that
clear-cutting did not have an effect on modifying the distribution of nutrient concentrations. These results suggest that
after 15 and 25 yr following forest disturbance nutrient distributions were reestablished either there was not a net effect
on patterns of element loss or tidal input was stronger than plant modifications of soils. 相似文献
15.
Yongcun Zhao Xianghua Xu Jeremy Landon Darilek Biao Huang Weixia Sun Xuezheng Shi 《Environmental Geology》2009,57(5):1089-1102
Topsoil samples (0–20 cm) (n = 237) were collected from Rugao County, China. Geostatistical variogram analysis, sequential Gaussian simulation (SGS),
and principal component (PC) analysis were applied to assess spatial variability of soil nutrients, identify the possible
areas of nutrient deficiency, and explore spatial scale of variability of soil nutrients in the county. High variability of
soil nutrient such as soil organic matter (SOM), total nitrogen (TN), available P, K, Fe, Mn, Cu, Zn, and B concentrations
were observed. Soil nutrient properties displayed significant differences in their spatial structures, with available Cu having
strong spatial dependence, SOM and available P having weak spatial dependence, and other nutrient properties having moderate
spatial dependence. The soil nutrient deficiency, defined here as measured nutrient concentrations which do not meet the advisory
threshold values specific to the county for dominant crops, namely rice, wheat, and rape seeds, was observed in available
K and Zn, and the deficient areas covered 38 and 11%, respectively. The first three PCs of the nine soil nutrient properties
explained 62.40% of the total variance. TN and SOM with higher loadings on PC1 are closely related to soil texture derived
from different parent materials. The PC2 combined intermediate response variables such as available Zn and P that are likely
to be controlled by land use and soil pH. Available B has the highest loading on PC3 and its variability of concentrations
may be primarily ascribed to localized anthropogenic influence. The amelioration of soil physical properties (i.e. soil texture)
and soil pH may improve the availability of soil nutrients and the sustainability of the agricultural system of Rugao County. 相似文献
16.
Influence of extractable soil manganese on oxidation capacity of different soils in Korea 总被引:1,自引:0,他引:1
We examined the relationship between soil oxidation capacity and extractable soil manganese, iron oxides, and other soil properties.
The Korean soils examined in this study exhibited low to medium Cr oxidation capacities, oxidizing 0.00–0.47 mmol/kg, except
for TG-4 soils, which had the highest capacity for oxidizing added Cr(III) [>1.01 mmol/kg of oxidized Cr(VI)]. TG and US soils,
with high Mn contents, had relatively high oxidation capacities. The Mn amounts extracted by dithionite-citrate-bicarbonate
(DCB) (Mnd), NH2OH·HCl (Mnh), and hydroquinone (Mnr) were generally very similar, except for the YS1 soils, and were well correlated. Only small proportions of either total
Mn or DCB-extractable Mn were extracted by NH2OH·HCl and hydroquinone in the YS1 soils, suggesting inclusion of NH2OH·HCl and hydroquinone-resistant Mn oxides, because these extractants are weaker reductants than DCB. No Cr oxidation test
results were closely related to total Mn concentrations, but Mnd, Mnh, and Mnr showed a relatively high correlation with the Cr tests (r = 0.655–0.851; P < 0.01). The concentrations of Mnd and Mnh were better correlated with the Cr oxidation tests than was the Mnr concentration, suggesting that the oxidation capacity of our soil samples can be better explained by Mnd and Mnh than by Mnr. The first component in principal components analysis indicated that extractable soil Mn was a main factor controlling net
Cr oxidation in the soils. Total soil Mn, Fe oxides, and the clay fraction are crucial for predicting the mobility of pollutants
and heavy metals in soils. The second principal component indicated that the presence of Fe oxides in soils had a significant
relationship with the clay fraction and total Mn oxide, and was also related to heavy-metal concentrations (Zn, Cd, and Cu,
but not Pb). 相似文献
17.
X. J. Wang R. M. Liu K. Y. Wang J. D. Hu Y. B. Ye S. C. Zhang F. L. Xu S. Tao 《Environmental Geology》2006,49(8):1208-1216
Polycyclic aromatic hydrocarbons (PAHs) in soil originate from various sources under different spatial scales. Coregionalization
analysis is more revealing than univariate geostatistical analysis. Scale-dependent spatial features of variables reflect
different sources of spatial variability. In this study, 188 topsoil samples in the Tianjin area were collected. The contents
of 16 PAHs and soil background properties were determined for all samples. A multivariate geostatistical approach was used
for multi-scale spatial analysis for PAH compounds. Results show that coal combustion was the major source for the spatial
distribution patterns of PAHs in the topsoil of the studied area. It worked mainly at the short-range scale (5–10 km). Significant
spatial variation patterns were identified. In contrast, no significant spatial distribution trends at the nugget (0–5 km)
or long-range scales (10–50 km) were seen. Long-range transport and site contamination of PAHs might not be key contributors
in forming the distribution pattern of PAHs in the topsoil of Tianjin area. 相似文献
18.
Based on sampling depths, the research environment of the soil in a study area is divided into two parts: the I environment
(I-E) and the II environment (II-E). The results of the statistical analysis of arsenic (As) in the soil of the I-E indicates
that the statistical characteristic value obey a normal distribution. The mean value of As is close to the world mean value,
China and Tianjin City. Also, the contrast between the spatial change characteristics of As of the I-E and the II-E soils
showed that the I-E resembles the II-E in the content variety of As. On the other hand, geochemistry methods were applied
in the estimation of contaminated extent. The results indicated that the contamination extent of the north of Tianjin City
has not been serious.
__________
Translated from Geological Bulletin of China, 2007, 26(11): 1486–1493 [译自: 地质通报] 相似文献
19.
文章对石家庄市土壤重金属含量水平进行了研究,通过采集的220个城市土壤样品,分析了Al2O3、As、Cd、Cr、Cu、Ni、Pb、Zn等8个元素。结果表明,与土壤背景值相比,石家庄市土壤中除As和Al2O3外的重金属含量总体明显升高。采用相关分析和主成分分析,对土壤重金属元素来源进行解析,认为有3种主要来源:一是Cu、Zn、Pb与人类的工业生产、汽车尾气排放有关。二是Ni、Cr、Cd除与工业生产有关外,还与燃煤活动排放有关。三是As、Al2O3主要与土壤母质有关(自然来源)。石家庄城市土壤的重金属含量高值区与工业区域、交通分布相吻合。 相似文献
20.
Jun Wang Zhenlou Chen Xiaojing Sun Guitao Shi Shiyuan Xu Dongqi Wang Li Wang 《Environmental Earth Sciences》2009,59(3):645-654
Associated with the rapid urbanization and industrialization, most of the urban parks and recreational areas in Shanghai are
built close to major roads or industrial areas, where they are subject to many potential pollution source, including automobile
exhaust and factory emissions. Urban dusts, containing many toxic heavy metals such as Pb, Cr, Cd, Hg and As, are one of main
contributors for environmental pollution. In this study, 261 dust samples were collected from two different localities (streets
and parks) in the urban area of Shanghai, China. Pb and Cr concentrations of all samples were determined by atomic adsorption
spectrophotometer analyzer, and Cd, As and Hg concentrations in 74 samples by atomic fluorescence spectroscopy. The mean concentrations
of Pb, Cr, Cd, As and Hg are 287, 157, 1.24, 8.73 and 0.16 mg kg−1, respectively. Each heavy metal shows a wide range of concentration values. In comparison with heavy metal background values
of soil in Shanghai, urban dusts have elevated metal concentrations as a whole, except those of As. The concentrations of
Pb, Cr, Cd, As and Hg are 11.3, 2.1, 10.3, 0.997, 1.7 times of the soil background values, respectively. Compared with the
global mean concentrations, Cr concentration in urban dusts is slightly higher. Pb, Cr and Hg show normal distribution after
logarithmic transformation. Pb, Cr, Cd, As and Hg have second-order variation trends of the spatial distribution. The spatial
distribution features of five toxic heavy metals, in general, illustrate relatively high levels within the regions of the
inner-city ring highway and southwestern Shanghai. Cr and Cd are higher in Baoshan industrial park and the shipbuilding industries
regions. The order of environmental risk is Pb > Cd > Cr > Hg > As. Pb and Cd have the highest risk for environment pollution
and human health among the five metals. The pollutant sources of toxic heavy metals in Shanghai urban dusts are preliminarily
concluded as follows: As may have mainly a natural source. Burning of coal has become the main source of Hg pollution. Pb,
Cr and Cd have three sources, traffic, building construction, and weathering corrosion of building materials. 相似文献