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1.
The distribution of Si, Al, Fe, Mn, Cu, Zn, Ni and Cr in different grain-size fractions and geochemical association of Fe,
Mn, Cu and Zn with <63-μm size fraction of bed sediments of Damodar River has been studied. In general, concentrations of
heavy metals tend to increase as the size fractions get finer. However at two sites, near mining areas, the coarser particles
show similar or even higher heavy metal concentrations than finer ones. The higher residence time and/or presence of coarser
particles from mining wastes are possibly responsible for higher metal content in the coarser size fractions. The chemical
fractionation study shows that lithogenic is the major chemical phase for heavy metals. Fe and Mn are the major elements of
the lithogenic lattice, constituting 34–63% and 22–59%, respectively, of total concentrations. Fe-Mn oxide and organic bound
fractions are significant phases in the non-lithogenic fraction. The carbonate fraction is less significant for heavy metal
scavenging in the present environment and shows the following order of abundance Zn>Cu>Mn>Fe. The exchangeable fraction of
the Damodar sediments contains very low amounts of heavy metals suggesting poor bioavailability of metals.
Received: 18 August 1998 · Accepted: 1 December 1998 相似文献
2.
Heavy meals in urban roadside soils, part 1: effect of particle size fractions on heavy metals partitioning 总被引:8,自引:0,他引:8
Urban roadside soils are important environmental media for assessing heavy metal concentrations in urban environment. However, among other things, heavy metal concentrations are controlled by soil particle grain size fractions. In this study, two roadside sites were chosen within the city of Xuzhou (China) to reflect differences in land use. Bulk soil samples were collected and then divided by particle diameter into five physical size fractions, 500–250, 250–125, 125–74, 74–45, < 45 μm. Concentrations of metals (Ti, Cr, Al, Ga, Pb, Ba, Cd, Co, Cu, Mn, Ni, V, Zn, Mo, As, Sb, Se, Hg, Bi, Ag) were determined for each individual fraction. These metals could be roughly classified into two groups: anthropogenic element (Pb, Ba, Cd, Cu, Zn, Mo, As, Sb, Se, Hg, Bi, Ag) and lithophile element (Ti, Cr, Al, Ga, Co, Mn, Ni, V) in terms of values of enrichment factor. As expected, higher concentrations of anthropogenic heavy metals (Cu, Zn, Mo, As, Hg, Bi, Ag) are observed in the finest particle grain size fraction (i.e. < 45 μm). However, heavy metals Se, Sb and Ba behave independently of selected grain size fractions. From the viewpoint of mass loading, more than 30% of the concentrations for all anthropogenic heavy metals are contributed by the particle grain size fractions of 45–74 μm at site 1 and more than 70% of the concentrations for all heavy metals are contributed by the particle grain size fractions of 45–74 and 74–125 μm at site 2. These results are important for transport of soil-bound heavy metals and pollution control by various remedial options. 相似文献
3.
Heavy metal contamination of coastal lagoon sediments by anthropogenic activities: the case of Nador (East Morocco) 总被引:1,自引:0,他引:1
Nador lagoon sediments (East Morocco) are contaminated by industrial iron mine tailings, urban dumps and untreated wastewaters
from surrounding cities. The lagoon is an ecosystem of biological, scientific and socio-economic interests but its balance
is threatened by pollution already marked by biodiversity changes and a modification of foraminifera and ostracods shell structures.
The aim of the study is to assess the heavy metal contamination level and mobility by identifying the trapping phases. The
study includes analyses by ICP-AES and ICP-MS, of, respectively, major (Si, Al, Mg, Ca, Fe, Mn, Ti, Na, K, P) and trace elements
(Sr, Ba, V, Ni, Co, Cr, Zn, Cu, As, Pb, Cd) in sediments and suspended matter, heavy metals enrichment factors calculations
and sequential extractions. Results show that sediments contain Zn, Cu, Pb, V, Cr, Co, As, Ni with minimum and maximum concentrations,
respectively, of 4–1190 μg/g, 4–466 μg/g, 11–297 μg/g, 11–194 μg/g, 9–139 μg/g, 1–120 μg/g, 4–76 μg/g, 2–62 μg/g. High concentrations
in Zn are also present in suspended matter. The enrichment factors show contamination in Zn, Pb and As firstly induced by
the mining industry and secondly by unauthorized dumps and untreated wastewaters. Cr and Ni are bound to clays, whereas V,
Co, Cu and Zn are related to oxides. Thus, the risk in metal mobility is for the latter elements and lies in the oxidation–reduction-changing
conditions of sediments. 相似文献
4.
Metal contamination of the environment by placer and primary gold mining in the Adola region of southern Ethiopia 总被引:3,自引:0,他引:3
Primary and placer gold mining sites in southern Ethiopia were studied to see the contribution of mining to the accumulation of metals in different environmental media. Sediment, water and plant samples were analyzed for Al, Mn, Fe, As, Ni, Cr, Cu, Co, Pb, W, Sb, Mo, Zn and V. Water parameters (pH, Eh, TDS, anions and cations) were also measured. The sediment analyses results show that the most abundant metals are Ni (average 224.7 mg/kg), Cr (199 mg/kg), Cu (174.2 mg/kg), V (167.3 mg/kg), Zn (105.5 mg/kg), Pb (61.5 mg/kg) and As (59.7 mg/kg) in the primary gold mining sites while the placer sites show high concentration of V (average 301.2 mg/kg), Cr (260.4 mg/kg), Zn (179 mg/kg), Ni (113.4 mg/kg), Cu (46.7 mg/kg), As (32.2 mg/kg) and Co (31 mg/kg). The metals Cu, Ni, W, Cr, As and Pb in primary and Sb, W, Cr, Ni, Zn, As and Mo in placer gold mining sites have geoaccumulation indexes (I
geo) from one to four indicating considerable accumulation of these metals. Waters from both primary and placer mining sites are near neutral to alkaline. Arsenic (average 92.8 μg/l), Ni (276.6 μg/l), Pb (18.7 μg/l), Sb (10.7 μg/l), Mn (1 mg/l), Fe (8.3 mg/l) and Al (23.8 mg/l) exceeded the guideline value for drinking water. Plants show high concentration of Cr (average 174.5 mg/kg), Ni (163.5 mg/kg), Zn (96 mg/kg) and W (48 mg/kg). Zinc, W, Mo, Ni and Cr show the maximum biological absorption coefficient (BAC) ranging 0.4–1.7, 0.1–104.6, 1.1–2.6, 0.2–1.6 and 0.2–3.6, respectively, and the results suggest bioaccumulation of these elements in plants. The minerals especially sulfides in the ore aggregate are the ultimate source of the metals. The release of the metals into the environmental media is facilitated (in addition to normal geologic processes) by human activities related to gold mining. 相似文献
5.
Distribution and enrichment of trace metals in marine sediments of Bay of Bengal,off Ennore,south-east coast of India 总被引:1,自引:0,他引:1
In order to avoid the pollution of trace metals in marine environment, it is necessary to establish the data and understand
the mechanisms influencing the distribution of trace metals in marine environment. The concentration of heavy metals (Fe,
Mn, Cr, Cu, Ni, Pb, Zn, Co and Cd) were studied in sediments of Ennore shelf, to understand the metal contamination due to
heavily industrialized area of Ennore, south-east coast of India. Concentration of metals shows significant variability and
range from 1.7 to 3.7% for Fe, 284–460 μg g−1 for Mn, 148.6–243.2 μg g−1 for Cr, 385–657 μg g−1 for Cu, 19.8–53.4 μg g−1 for Ni, 5.8–11.8 μg g−1 for Co, 24.9–40 μg g−1 for Pb, 71.3–201 μg g−1 for Zn and 4.6–7.5 μg g−1 for Cd. For various metals the contamination factor (CF) and geoaccumulation index (I
geo) has been calculated to assess the degree of pollution in sediments. The geoaccumulation index shows that Cd, Cr and Cu moderately
to extremely pollute the sediments. This study shows that the major sources of metal contamination in the Ennore shelf are
land-based anthropogenic ones, such as discharge of industrial wastewater, municipal sewage and run-off through the Ennore
estuary. The intermetallic relationship revealed the identical behavior of metals during its transport in the marine environment. 相似文献
6.
Assessing the concentration and potential dietary risk of heavy metals in vegetables at a Pb/Zn mine site,China 总被引:7,自引:0,他引:7
Jun Dong Qing-wei Yang Li-na Sun Qing Zeng Shou-jiang Liu Jin Pan Xue-lian Liu 《Environmental Earth Sciences》2011,64(5):1317-1321
Cd, Pb, Cu and Zn were measured in vegetables in Xiguadi village around Lechang Pb/Zn mine in Guangdong province, South China.
The daily intake (DI) of these metals from vegetables by local people was also determined. The respective Cd, Pb, Cu and Zn
concentration was 0.05–0.90 (mean 0.25), 1.04–5.82 (2.64), 0.53–7.07 (2.00) and 3.87–25.20 (11.68) mg kg−1, of which Cd concentration in all vegetables exceeded the safe limit given by FAO/WHO. The DI was found to be 49.76, 475.56,
360.36 and 2,102.63 μg, respectively. The present results indicated local mining activity caused vegetable heavy metal contamination
and Cd concentration exceeding the stipulated standards for all vegetables indicating potentially serious dietary risks for
local people. 相似文献
7.
Ahmed Melegy 《Geotechnical and Geological Engineering》2010,28(5):549-558
Activated carbons have been proven to be effective adsorbents for the removal of Pb (II) and Zn (II) dissolved in aqueous
media. The study of adsorption of Pb (II) and Zn (II) on two different size fractions from a composite coal sample of Maghara
coal mine, C63 (63–125 μm) and C250 (125–250 μm) is presented in this paper. C63 and C250 were treated in water solutions of 50 mM lead and zinc acetates. X-ray photoelectron spectroscopy (XPS) was used to characterize
the starting and treated coal surfaces. The high surface area and surface functional groups (carboxy and phenolic) enable
activated bituminous coal of Maghara to act as efficient adsorbents for removing dissolved Pb (II) and Zn (II) in alkaline
medium. 相似文献
8.
Magnetic enhancement of urban roadside soils as a proxy of degree of pollution by traffic-related activities 总被引:1,自引:1,他引:0
Detailed magnetic and geochemical measurements were performed on urban roadside soils collected from Lishui city, China, to
establish a possible link between the enhanced concentration of traffic-related magnetic particles and heavy metals. Relatively
higher magnetic susceptibility (mean: 124.1 × 10−8 m3 kg−1) and concentrations of metals (Cd, Cu, Pb and Zn) were observed for roadside soils. Concentration-dependent magnetic parameters
(χ and SIRM) are highly significantly positively correlated to the concentration of metals (Ca, Cr, Ni, Cu, Zn, Cd, Pb, Fe,
and V), but not significantly correlated with As, Mn, Co, Mg, and K. The principal component analysis showed that χ and SIRM
significantly correspond to elements Ca, Cd, Cu, Pb, and Zn. The χ and SIRM also have significant linear correlation with
integrated pollution index, indicating that χ and SIRM can be used as effective proxy indicators for the pollution of heavy
metals. Magnetite in the pseudo-single-domain/multidomain (PSD/MD) grain size was identified as the dominant magnetic carrier
by temperature-dependent measurements of saturation magnetization (Ms–T curve), XRD and hysteresis loops. Field emission scanning
electron microscopy and energy dispersive X-ray spectroscopy (EDS) analysis of the magnetic particles revealed the presence
of large traffic-related angular-subangular, blocky, and spherical iron oxide particles. These iron oxide particles are typical
for particles produced by traffic-related anthropogenic activities. It is concluded that vehicle emissions may be the major
source of elevated heavy metals and magnetic particles in roadside soils. The results proved the applicability of magnetic
method in detecting roadside pollution derived from vehicle emissions. 相似文献
9.
This paper examines the surface sediments collected from Dongping Lake in China for speciation and distribution of toxic heavy metals (Cu, Pb, Ni, Cd) in different grain size fractions, and for the factors that need to be considered in potential hazard of metals to the environment. Four grain size fractions (<63, 63–78, 78–163 and 163–280 μm), divided in wet condition, and bulk samples less than 280 μm in diameter were analyzed for their distribution, density and appearance. A three-stage extraction procedure following the BCR protocol was used to chemically fractionate metals into “acid soluble”, “reducible”, “oxidizable” and “residual” fractions. Correlation analysis was used to analyze the datasets. The results showed that <63 μm grain size part constitutes the major proportion of the sediments, but its density is the smallest among the four grain size fractions. In general, the metal content curve against grain size presents “S” distribution, and the highest concentrations do not exist in <63 μm grain size. Appearance observation indicates that the adsorbed substance increases gradually along with the decreasing grain size. The dominant speciation of elements and the extent of pollution are responsible for the metal distribution in different grain size sediments. While studying bioavailability and mobilization of metals, it is advisable to take metal speciation, grain size distribution and density into consideration. 相似文献
10.
A comparison of geochemical information obtained from two fluvial bed sediment fractions 总被引:4,自引:1,他引:3
Ross. A. Sutherland 《Environmental Geology》2000,39(3-4):330-341
A total of 121 bed sediment samples were collected from a 5.8-km stretch of Manoa Stream, Hawaii. Samples were physically
partitioned into two grain-size fractions, <63 μm and 63–125 μm, acid digested and analyzed by ICP-AES and FAAS. Non-parametric
matched-pair statistical testing and correlation analysis were used to assess differences and strengths of association between
the two fractions for Al, Ba, Cu, Fe, Mn, Ni, Pb, Ti and Zn. Results indicated statistically significant differences between
fractions for all elements except Mn. Concentrations were significantly greater in the <63 μm fraction for Al, Cu, Pb, Ti
and Zn, while Ba, Fe and Ni were higher in the 63–125 μm fraction. Though some elements had statistically significant differences
between fractions (Al, Ba, Fe and Zn) percentage differences were in the range of analytical precision of the instrument and
thus differences were not practically significant. Correlation analysis indicated strong positive associations for all elements
between the two fractions (p<0.0001). Three contamination indices indicated similar degrees of pollution for each size fraction
for four elements having an anthropogenic signal (Ba, Cu, Pb and Zn). The environmental information obtained from the 63–125 μm
fraction was essentially equivalent to that from the <63 μm fraction. In this system it is clear that both bed sediment fractions
indicate anthropogenic enrichment of trace metals, especially Pb, and further supports previous research that has found that
aquatic sediments are critical median for tracing sources of pollution.
Received: 17 August 1998 · Accepted: 30 October 1998 相似文献
11.
Urban roadside soils are the “recipients” of large amounts of heavy metals from a variety of sources including vehicle emissions,
coal burning waste and other activities. The behavior of heavy metals in urban roadside soils depends on the occurrence as
well as the total amount. Accordingly, knowledge of the interactions between heavy metals and other constituents in the soil
is required to judge their environmental impact. In this study, correlations of heavy metal concentrations (Pb, Zn, Cu, Ag,
Se, Ni, Cr and Ba) to iron extracted using dithionite–citrate–bicarbonate (DCB) buffer (FeDCB), fulvic acids and particle size fractions were examined from the Xuzhou urban roadside soils. Heavy metals except for Cr
and fulvic acids had a positive significant correlation with FeDCB, indicating these metals and fulvic acids are principally associated with the surfaces of iron oxides of the soils. Significant
positive correlations were also found between the contents of fulvic acids and heavy metals, showing these heavy metals (especially
for Cu, Ni and Cr) form stable complexes with fulvic acids. Such finding is of importance with regard to the increased mobilization
of heavy metals, e.g., into freshwater ecosystems. Ag, Se and Cr are independent of particle size fractions because of their
low concentrations of Ag and Se in the studied soils. Pb, Zn, Cu, Ba and Ag are mainly enriched in the finer soil particles
(especially <16 μm). 相似文献
12.
Bo Peng Xiaoya Tang Changxun Yu Changyin Tan Chunyan Yin Guang Yang Qian Liu Kesu Yang Xianglin Tu 《Environmental Earth Sciences》2011,64(5):1455-1473
This paper reports a geochemical study of trace metals and Pb isotopes of sediments from the lowermost Xiangjiang River, Hunan
province (P. R. China). Trace metals Ba, Bi, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, Mo, Cd, Sn, Sb, Pb, Tl, Th, U, Zr, Hf, Nb and
Ta were analyzed using ICP-MS, and Pb isotopes of the bulk sediments were measured by MC-ICP-MS. The results show that trace
metals Cd, Bi, Sn, Sc, Cr, Mn, Co, Ni, Cu, Zn, Sb, Pb and Tl are enriched in the sediments. Among these metals, Cd, Bi and
Sn are extremely highly enriched (EF values >40), metals Zn, Sn, Sb and Pb significantly highly (5 < EF < 20), and metals
Sc, Cr, Mn, Co, Ni, Cu and Tl moderately highly (2 < EF < 5) enriched in the river sediments. All these metals, however, are
moderately enriched in the lake sediments. Geochemical results of trace metals Th, Sc, Co, Cr, Zr, Hf and La, and Pb isotopes
suggest that metals in the river sediments are of multi-sources, including both natural and anthropogenic sources. Metals
of the natural sources might be contributed mostly from weathering of the Indosinian granites (GR) and Palaeozoic sandstones
(PL), and metals of anthropogenic sources were contributed from Pb–Zn ore deposits distributed in upper river areas. Metals
in the lake sediments consist of the anthropogenic proportions, which were contributed from automobile exhausts and coal dusts.
Thus, heavy-metal contamination for the river sediments is attributed to the exploitation and utilization (e.g., mining, smelting,
and refining) of Pb–Zn ore mineral resources in the upper river areas, and this for the lake sediments was caused by automobile
exhausts and coal combustion. Metals Bi, Cd, Pb, Sn and Sb have anthropogenic proportion of higher than 90%, with natural
contribution less than 10%. Metals Mn and Zn consist of anthropogenic proportion of 60–85%, with natural proportion higher
than 15%. Metals Sc, Cr, Co, Cu, Tl, Th, U and Ta have anthropogenic proportion of 30–70%, with natural contribution higher
than 30%. Metals Ba, V and Mo might be contributed mostly from natural process. 相似文献
13.
Contamination and potential mobility assessment of heavy metals in urban soils of Hangzhou,China: relationship with different land uses 总被引:1,自引:0,他引:1
Concentration and distribution of heavy metals (Cd, Cu, Pb and Zn) in urban soils of Hangzhou, China, were measured based
on different land uses. The contamination degree of heavy metals was assessed on the basis of pollution index (PI), integrated
pollution index (IPI) and geoaccumulation index (I
geo). The 0.1 mol l−1 HCl extraction procedure and gastric juice simulation test (GJST) were used to evaluate the potential mobility and environmental
risk of heavy metals in urban soils. The average concentration of Cd, Cu, Pb and Zn in urban soils was measured at 1.2 (with
a range of 0.7–4.6), 52.0 (7.4–177.3), 88.2 (15.0–492.1) and 206.9 (19.3–1,249.2) mg kg−1, respectively. The degree of contamination increased in the order of industrial area (IA) > roadside (RS) > residential and
commercial areas (RC) > public park and green areas (PG). The PIs for heavy metals indicated that there is a considerable
Cd, Cu, Pb and Zn pollution, which originate from traffic and industrial activities. The IPI of these four metals ranged from
1.6 to 11.8 with a mean of 3.5, with the highest IPI in the industrial area. The assessment results of I
geo also supported that urban soil were moderately contaminated with Cd and to a lesser extent also with Cu, Pb and Zn. The IP
and I
geo values reveal the pollution degree of heavy metal was the order of Cd > Pb > Zn ≈ Cu. It was shown that mobility and bioavailability
of the heavy metals in urban soils increased in the order of Cd > Cu > Zn ≈ Pb. Owing to high mobility of Cd and Cu in the
urban soils, further investigations are needed to understand their effect on the urban environment and human health. It is
concluded that industrial activities and emissions from vehicles may be the major source of heavy metals in urban contamination.
Results of this study present a rough guide about the distribution and potential environmental and health risk of heavy metals
in the urban soils. 相似文献
14.
Mobility and ecological risk assessment of heavy metals in surface sediments of Xiamen Bay and its adjacent areas,China 总被引:4,自引:1,他引:3
Xiamen Bay (XMB) has received substantial loadings of pollutants from industrial and municipal wastewater discharged since
the 1980s. To assess ecological risks and the current spatial changes of metal contaminants in bottom surface sediments, 12
samples were collected. Samples were subjected to a total digestion technique and analyzed by ICP–OES for Cu, Pb, Zn, Cr,
and Cd, and by AFS for Hg and As. Among these metals, Zn had the highest values (68–268 mg kg−1), followed by Pb (27–71 mg kg−1), and lower concentrations were found for Cd (42–1,913 μg kg−1) and Hg (0–442 μg kg−1). In comparison with the average crustal abundance values, the results indicated that nearly half of the sediment samples
of XMB and its adjacent areas were contaminated by Cd, Pb, Zn, and As. Furthermore, based on the modified BCR sequential extraction
procedure, the chemical speciation of heavy metals (Cd, Cr, Cu, Pb, Zn, Hg, and As) in selected sediment samples were evaluated
in this study. Data from BCR sequential extractions indicated that Cd posed a medium ecological risk, whereas, Cr posed low
risk since its exchangeable and carbonate fractions were below 4%, and the mobility of heavy metals in XMB decreased in the
order Cd > Pb > Cu > Zn > Hg > As > Cr. By applying mean effects range median quotients (mERMQ), the results showed that Yuandang
Lagoon with mERMQ value >0.5 would be expected to have the greatest potential toxic risk in amphipod within XMB and its adjacent
areas. 相似文献
15.
Spatial variability of heavy metals in soils across a valley plain in Southeastern China 总被引:1,自引:0,他引:1
An investigation was carried out to survey the magnitude and spatial distribution of heavy metals, as well as their relation
with soil series, in a valley plain in Southeastern China. Soil was sampled at 159 sites by combining a squared grid and nested
sampling strategies along the transect perpendicular to the Qujiang River in Zhejiang Province, China. Total concentrations
of six metals, namely Cu, Fe, Mn, Ni, Pb and Zn, were measured. Classical statistics and geostatistics were used to quantify
their spatial characteristics. There was a considerable variation in many of these parameters. The total concentrations ranged
from 6.8 to 29.3 mg kg−1 for Cu, 6,784 to 18,678 mg kg−1 for Fe, 94 to 385 mg kg−1 for Mn, 6.1 to 20.3 mg kg−1 for Ni, 25.0 to 49.5 mg kg−1 for Pb, and 12 to 160 mg kg−1 for Zn. Pearson correlation coefficients among total metal concentrations and selected soil properties showed a number of
strong associations. By virtue of analysis of variance, a predominant influence of soil series on the spatial variability
of metal concentrations was observed. All metals were spatially correlated. The semivariograms of Cu, Fe, Mn, Ni and Zn were
dominated by short range correlation (600 or 700 m), and that of Pb by long range (1200 m). Block kriging maps of total metal
concentrations and soil properties showed strip distributions, perpendicular to the river, in the manner similar to the soil
series. Principal component analysis was run to identify common distribution patterns of heavy metals and soil properties.
These results illustrate that soil series information of valley plain may be useful for developing management zones for site-specific
agriculture. 相似文献
16.
Asmae Mhamdi Alaoui Mohamed Choura Mohamed Maanan Bendahhou Zourarah Marc Robin Maria Freitas Conceição César Andrade Mehdi Khalid Christian Carruesco 《Environmental Earth Sciences》2010,61(2):275-286
The metal content in surface sediments (0–2 cm, 26 samples), in a sediment core (120, 1 cm slices), taken from Moulay Bousselham
(Morocco) was investigated. Concentrations of Al, Fe, Mn, Pb, Zn, Cu, Ni, Cr, Cd, As, and Hg were evaluated in surface and
cored sediments of Moulay Bousselham lagoon. Significantly high concentrations in μg g−1 dw of Pb (31.7–6.2), Zn (758.9–167), Cu (310.7–22), Ni (96–10.5), Cr (113–18.9), Cd (0.84–0.02), As (1–0.1), and Hg (0.61–0.02)
were found in sediment samples from Moulay Bousselham lagoon. Calculated enrichment factors [EFMe = (Me/Al)sample/(Me/Al)background], using Al as a normalizer, and correlation matrices showed that metal pollution in Merja Zerga of Moulay Bousselham lagoon
was the product of anthropogenic sources, while the metal content in Merja Kehla was of natural origins. The results suggest
that a major change in the sedimentary regime of the lagoon, associated with internal trapping and re-distribution of heavy
metal, has been occurring in the past few decades. The cause would appear to be the construction of a Nador Canal at the lagoon.
Probable effects concentrations (PEC) were often exceeded for heavy metals in the lagoon sediments, especially for Zn, Cu,
Ni, and Cr, and four stations, stations MZ-11, MZ-12, MZ-13, MZ-14, MZ-16, and MZ-17, had multiple metals at presumptively
toxic levels. These comparisons suggest that sediment metal levels in the river are clearly high and probably pose an environmental
risk at some stations. The levels of most of the metals were not greatly enriched, a consideration that is of the utmost importance
when contamination issues are at stake. Metal concentrations found in Moulay Bousselham lagoon were comparable to aquatic
systems classified as contaminated from other regions of the world. 相似文献
17.
Juan C. Bidegain Marcos A. E. Chaparro Débora C. Marié Sandra Jurado 《Environmental Earth Sciences》2011,62(4):847-855
Environmental pollution and its harmful consequences for the population’s health derived from coal production in the locality
of Ensenada (Argentina) is studied by magnetic and non-magnetic means. Coke is used for the production of industrial coal.
This is a final product obtained in petroleum refineries. Coke is a non-magnetic material showing values of magnetic susceptibility
close to zero. Conversely, the magnetic susceptibility of the coal released from factory chimneys is considerably enhanced
due to the building of magnetic fibers and spherules inside the furnace, used for coal production. Due to this property, the
magnetic content of coal can be used as environmental proxy for studying the environmental impact caused by coal industries
in urban areas. The values of magnetic susceptibility decrease as the distance from the contamination source increases. This
indicates that magnetic concentration is lower. The grain size of magnetic particles also decreases according to the distance,
which is seen when analyzing the grain size parameters. According to the different non-magnetic approaches applied, the particles
released by the industry, which affect the region, fall within the rank of breathable particles (<2.5 μm). Besides, inhalable
particles are also found (2.5–10 μm). Such determinations are consistent with inter-parametric ratios applied in the study
of grain sizes. The undesirable dust of the local coal industry also carries heavy metals which are dangerous for the population’s
health, like Zn, Cu, Pb and V. 相似文献
18.
Accumulation of heavy metals in wild commercial fish from the Baotou Urban Section of the Yellow River,China 总被引:1,自引:0,他引:1
In this work we studied the accumulation of heavy metals in nine species of fish with different life and feeding habitats
which are native and major commercial fish in the Baotou Urban Section of the Yellow River. The results showed that the concentration
of heavy metals was significantly dependent on fish species; the pollution index of heavy metals in different species were
ranked as Hemiculter leucisclus > Carassius auratus auratus > Hemibarbus maculatus > Megalobrama amblycephala > Abbottina rivularis > Cyprinus carpio > Squaliobarbus curriculus > Perccottus glehni > Saurogobio dabryi. Product–moment correlation coefficients among the metal pairs Pb–Zn, Cu–Cd, Cu–Zn, Cu–Pb, Pb–Cd, and Zn–Cd revealed there
was no competitions between metals in each tissue. Correlations between heavy metal concentrations and fish length or weight
indicated that accumulation of the heavy metals by the different fish species was related to their surrounding environments
and their life and feeding habitats. According to the mean bioconcentration factors (BCFs), the heavy metal concentrations
in these nine species were ranked Zn ≫ Cu > Cd ≈ Pb. In this work, the bioaccumulation factors (BAFs) were developed by using
the sum of exchangeable and bound-to-carbonate heavy metals as Cs values. It was found that BAFs better reveal the accumulation
characteristics of the heavy metals in the fish, which might provide an effective method for assessing bioaccumulation of
heavy metals. 相似文献
19.
Distribution of Cd,Pb, Zn and Cu and their chemical speciations in soils from a peri-smelter area in northeast China 总被引:2,自引:0,他引:2
An exploratory study on soil contamination of heavy metals was carried out surrounding Huludao zinc smelter in Liaoning province,
China. The distribution of total heavy metals and their chemical speciations were investigated. The correlations between heavy
metal speciations and soil pH values in corresponding sites were also analyzed. In general, Cd, Zn, Pb, Cu and As presented
a significant contamination in the area near the smelter, comparied with Environmental Quality Standards for Soils in China.
The geoaccumulation index showed the degree of contamination: Cd > Zn > Pb > Cu > As. There was no obvious pollution of Cr
and Ni in the studied area. The speciation analysis showed that the dominant fraction of Cd and Zn was the acid soluble fraction,
and the second was the residual fraction. Pb was mostly associated with the residual fraction, which constituted more than
50% of total concentration in all samples. Cu in residual fraction accounted for a high percentage (40–80%) of total concentration,
and the proportion of Cu in the oxidizable fraction is higher than that of other metals. The distribution pattern of Pb and
Zn was obviously affected by soil pH. It seemed that Pb and Zn content in acid solution fraction increased with increasing
soil pH values, while Cd content in acid soluble fraction accounted for more proportion in neutral and alkaline groups than
acidic one. The fraction distribution patterns of Cu in three pH groups were very similar and independent of soil pH values.
And the residual fraction of Cu took a predominant part (50%) of the total content. 相似文献
20.
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