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1.
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
2.
Heavy metals in sediments of a large, turbid tropical lake affected by anthropogenic discharges 总被引:2,自引:0,他引:2
Bottom-water data and trace metal concentration of Cu, Cr, Ni, Pb, Co, Zn, and organic matter in surficial sediment samples
from 13 sampling stations of Lake Chapala in Mexico were studied. The lake is turbid with a great amount of flocculated sediments
as a result of wind mixing, sediment re-suspension, and Lerma River discharges. Al distribution pattern in sediments was used
as an indicator of the Lerma River discharges into Lake Chapala. The highest values of Cu (33.27 ppm), Cr (81.94 ppm), Pb
(99.8 ppm), and Zn (149.7 ppm) were detected in sediments near the lake outlet. The bioavailable metal fraction is low for
all metals except Pb, which shows 65–93% of the total metal concentration in bioavailable form. The minimum energy zone in
the lake was related to organic matter concentration and was located in the SE part of the lake. An analysis of the studied
parameters shows two zones: eastern zone (fluvio-deltaic) and central-western zone (lacustrine).
Received: 9 September 1998 · Accepted: 16 November 1998 相似文献
3.
Munendra Singh 《Environmental Geology》2001,40(6):664-671
The Yamuna River sediments, collected from Delhi and Agra urban centres, were analysed for concentration and distribution
of nine heavy metals by means of atomic adsorption spectrometry. Total metal contents varied in the following ranges (in mg/kg):
Cr (157–817), Mn (515–1015), Fe (28,700–45,300), Co(11.7–28.4), Ni (40–538), Cu (40–1204), Zn (107–1974), Pb (22–856) and
Cd (0.50–114.8). The degree of metal enrichment was compared with the average shale concentration and shows exceptionally
high values for Cr, Ni, Cu, Zn, Pb and Cd in both urban centres. In the total heavy metal concentration, anthropogenic input
contains 70% Cr, 74% Cu, 59% Zn, 46% Pb, 90% Cd in Delhi and 61% Cr, 23% Ni, 71% Cu, 72% Zn, 63% Pb, 94% Cd in Agra. A significant
correlation was observed between increasing Cr, Ni, Zn, and Cu concentrations with increasing total sediment carbon and total
sediment sulfur content. Based on the Müller's geoaccumulation index, the quality of the river sediments can be regarded as
being moderately polluted to very highly polluted with Cr, Ni, Cu, Zn, Pb and Cd in the Delhi and Agra urban centres. The
present sediment analysis, therefore, plays an important role in environmental measures for the Yamuna River and the planning
of these city centres.
Received: 21 June 1999 · Accepted: 1 October 1999 相似文献
4.
Surface slices of 20 sediment cores, off southwestern Taiwan, and bed sediment of River Kaoping were measured for major and
trace elements (Al, As, Ca, Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, Ti, V, and Zn) to evaluate the geochemical
processes responsible for their distribution, including elemental contamination. Major element/Al ratio and mean grain size
indicate quartz-dominated, coarse grained sediments that likely derived from sedimentary rocks of Taiwan and upper crust of
Yangtze Craton. Bi-plot of SiO2 versus Fe2O3T suggests the possible iron enrichment in sediments of slag dumping sites. Highest concentrations of Cr, Mn, P, S, and Zn
found in sediments of dumping sites support this. Correlation analysis shows dual associations, detrital and organic carbon,
for Cr, P, S, and V with the latter association typical for sediments in dumping sites. Normalization of trace elements to
Al indicates high enrichment factors (>2) for As, Cd, Pb, and Zn, revealing contamination. Factor analysis extracted four
geochemical associations with the principal factor accounted for 25.1% of the total variance and identifies the combined effects
of dumped iron and steel slag-induced C–S–Fe relationship owing to authigenic precipitation of Fe–Mn oxyhydroxides and/or
metal sulfides, and organic matter complexation of Fe, Mn, Ca, Cr, P, and V. Factors 2, 3, and 4 reveal detrital association
(Ti, Al, Ni, Pb, Cu, and V), effect of sea salt (Cl, Mg, Na, and K) and anthropogenic component (As and Zn)-carbonate link,
respectively, in the investigated sediments. 相似文献
5.
Heavy metals in freshly deposited sediments of the Gomati River (a tributary of the Ganga River): effects of human activities 总被引:10,自引:0,他引:10
The concentrations of various metals (Cr, Cu, Co, Fe, Mn, Ni, Pb, Zn, and Cd) were determined in recently deposited surface
sediments of the Gomati River in the Lucknow urban area. Markedly elevated concentrations (milligrams per kilogram) of some
of the metals, Cd (0.26–3.62), Cu (33–147), Ni (45–86), Pb (25–77), and Zn (90–389) were observed. Profiles of these metals
across the Lucknow urban stretch show a progressive downstream increase due to additions from 4 major drainage networks discharging
the urban effluents into the river. The degree of metal contamination is compared with the local background and global standards.
The geoaccumulation index order for the river sediments is Cd>Zn>Cu>Cr>Pb. Significant correlations were observed between
Cr and Zn, Cr and Cu, Cu and Zn and total sediment carbon with Cr and Zn. This study reveals that the urbanization process
is associated with higher concentrations of heavy metals such as Cd, Cu, Cr, Pb, and Zn in the Gomati River sediments. To
keep the river clean for the future, it is strongly recommended that urban effluents should not be overlooked before their
discharge into the river.
Received: 16 February 1996 · Accepted: 29 February 1996 相似文献
6.
Speciation and phytoavailability of heavy metals in sediments in Nanjing section of Changjiang River 总被引:3,自引:1,他引:2
Heavy metal pollution and their fractionations in the sediments of Changjiang River in Nanjing Reach was monitored for cadmium
(Cd), lead (Pb), zinc (Zn), chromium (Cr), and copper (Cu). Moreover, the biological enrichment of metals by riverine plants
was studied. The results demonstrated there were highly significant variations among different sampling stations for the concentrations
of tested metals. The highest range was for Cu (38.8–120.4 mg kg−1), followed by Cr (74.4–120.0 mg kg−1), Zn (80.9–121.1 mg kg−1), Ni (26.0–55.5 mg kg−1), Pb (15.8–46.7 mg kg−1) and Cd (0.28–0.48 mg kg−1). Cd was the element with highest biological enrichment factor (BEF). The highest BEF of Cd in Erigeron bonariensis reached 3.0, indicating a significant Cd enrichment in this aquatic plant. In addition, 60% of Cd was found in reducible
fraction and exchangeable and acid-soluble fraction, which was consistent with its high mobility. The consistency of Cd fraction
in sediment and suspended particle indicated they came from the same source. Accumulated Cd concentration calculated according
to the release curve showed significant relativity with the total Cd concentration in the sediment. 相似文献
7.
Hun-Bok Jung Seong-Taek Yun Bernhard Mayer Soon-Oh Kim Seong-Sook Park Pyeong-Koo Lee 《Environmental Geology》2005,48(4-5):437-449
Transport and sediment–water partitioning of trace metals (Cr, Co, Fe, Pb, Cu, Ni, Zn, Cd) in acid mine drainage were studied
in two creeks in the Kwangyang Au–Ag mine area, southern part of Korea. Chemical analysis of stream waters and the weak acid
(0.1 N HCl) extraction, strong acid (HF–HNO3–HClO4) extraction, and sequential extraction of stream sediments were performed. Heavy metal pollution of sediments was higher
in Chonam-ri creek than in Sagok-ri creek, because there is a larger source of base metal sulfides in the ores and waste dump
upstream of Chonam-ri creek. The sediment–water distribution coefficients (K
d) for metals in both creeks were dependent on the water pH and decreased in the order Pb ≈ Al > Cu > Mn > Zn > Co > Ni ≈ Cd.
K
d values for Al, Cu and Zn were very sensitive to changes in pH. The results of sequential extraction indicated that among
non-residual fractions, Fe–Mn oxides are most important for retaining trace metals in the sediments. Therefore, the precipitation
of Fe(–Mn) oxides due to pH increase in downstream sites plays an important role in regulating the concentrations of dissolved
trace metals in both creeks. For Al, Co, Cu, Mn, Pb and Zn, the metal concentrations determined by 0.1 N HCl extraction (Korean
Standard Method for Soil Pollution) were almost identical to the cumulative concentrations determined for the first three
weakly-bound fractions (exchangeable + bound to carbonates + bound to Fe–Mn oxides) in the sequential extraction procedure.
This suggests that 0.1 N HCl extraction can be effectively used to assess the environmentally available and/or bioavailable
forms of trace metals in natural stream sediments. 相似文献
8.
Vertical distribution and water solubility of phosphorus and heavy metals in sediments of the St. Lucie Estuary, South Florida, USA 总被引:2,自引:0,他引:2
Accumulation and distribution of heavy metals and phosphorus in sediments impact water quality. There has been an increasing concern regarding fish health in the St. Lucie Estuary, which is related to increased inputs of nutrients and metals in recent decades. To investigate vertical changes of contaminants (P, Cd, Cr, Co, Cu, Ni, Pb, Zn, and Mn) in sediments of the St. Lucie Estuary in South Florida, 117 layer samples from six of the 210 to 420 cm depth cores were analyzed for their total and water-soluble P and heavy metals, clay, total Fe, Al, K, Ca, Mg, Na, and pH. Principal component analysis (PCA) was used in two sets of analytical data (total and water-soluble contaminant concentrations) to document changes of contaminants in each core of sediments. The PCA of total contaminants and minerals resulted in two factors (principal components). The first and second factors accounted for 61.7 and 17.2 % of the total variation in all variables, and contrast indicators associated with contaminants of P, Cd, Co, Cr, Ni, Pb, Zn, and Mn and accumulation of Fe and Al oxides, respectively. The first factor could be used for overall assessment of P and heavy metal contamination, and was higher in the upper 45–90 cm than the lower depths of each core. The concentrations of P and heavy metals in the surface layers of sediments significantly increased, as compared with those in the sediments deeper than 45–90 cm. The PCA of water-soluble contaminants developed two factors. The second factor (Cu–P) was higher in the upper than the lower depths of the sediment, whereas the highest score of the first factor (Cd–Co–Cr–Ni–Pb–Zn–Mn) occurred below 100 cm. The water-soluble Cu and P concentrations were mainly dependent on their total concentrations in the sediments, whereas the water-soluble Cd, Co, Cr, Ni, Pb, Zn, and Mn concentrations were mainly controlled by pH. 相似文献
9.
The Ganga Plain is one of the most densely populated regions and one of the largest groundwater repositories of the Earth.
For several decades, the drainage basin of the Ganga Plain has been used for the disposal of domestic and industrial wastes
which has adversely affected the quality of water, sediments and agricultural soils of the plain. The concentrations of Al,
Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sn, Zn and organic carbon were determined in river sediments and soils of the Ganga Plain
in the Kanpur-Unnao industrial region in 1994 and 1995 (pre-monsoon period of April–May). High contents (maximum values) of
C-org (12.0 wt. %), Cr (3.40 wt. %), Sn (1.92 wt. %), Zn (4000 mg/kg), Pb (646 mg/kg), Cu (408 mg/kg), Ni (502 mg/kg) and
Cd (9.8 mg/kg) in sediments (<20 μm fraction); and C-org (5.9 wt. %), Cr (2.16 wt. %), Sn (1.21 wt %), Zn (975 mg/kg) and
Ni (482 mg/kg) in soils (<20 μm) in the pre-monsoon period of 1994 were found. From 1994 to 1995 the contents of Fe and Sn
in sediments increase whereas those of C-org, Cd, Cu, Ni and Zn decrease. Considering the analytical errors, Al, Co, Cr, Mn
and Pb do not show any change in their concentrations. In soils, the contents of Cd, Fe and Sn increase whereas those of Ni
decrease from 1994 to 1995. Aluminium, Co, Cr, Cu, Mn, Pb and Zn do not show any change in their concentrations from 1994
to 1995. About 90% of the contents of Cd, Cr and Sn; 50–75% of C-org, Cu and Zn; and 25% of Co, Ni and Pb in sediments are
derived from the anthropogenic input in relation to the natural background values, whereas in soils this is the case for about
90% of Cr and Sn; about 75% of Cd; and about 25% of C-org, Cu, Ni and Zn. The sediments of the study area show enrichment
factors of 23.6 for Cr, 14.7 for Cd, 12.2 for Sn, 3.6 for C-org, 3.2 for Zn, 2.6 for Cu and 1.6 for Ni. The soils are enriched
with factors of 10.7 for Cr, 9.0 for Sn, 3.6 for Cd, 1.8 for Ni and 1.5 for Cu and Zn, respectively.
Received: 3 March 1998 · Accepted: 15 June 1998 相似文献
10.
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
11.
Trace metals (Cd,Pb, Cu,Zn and Ni) in sediment of the submarine pit Dragon ear (Soline Bay,Rogoznica, Croatia) 总被引:1,自引:0,他引:1
Vertical profiles of trace metal (Cd, Pb, Zn, Cu, Ni) concentrations, organic matter content, carbonate content and granulometric
composition were determined in two sediment cores from the submarine pit Dragon Ear (Middle Adriatic). Concentrations of the
analyzed metals (Cd: 0.06–0.12 mg kg−1, Pb: 28.5–67.3 mg kg−1, Zn: 17.0-65.4 mg kg−1, Cu: 21.1–51.9 mg kg−1, Ni: 27.8–40.2 mg kg−1) were in usual range for Adriatic carbonate marine sediments. Nevertheless, concentrations of Cu, Zn, and especially Pb in
the upper layer of sediments (top 12 cm) were higher than in bottom layer, while Cd and Ni concentration profiles were uniform.
Regression analysis and principal component analysis were used to interpret distribution of trace metals, organic matter and
carbonate content in sediment cores. Results of both analysis showed that concentrations of all trace metals in the core below
the entrance to the pit were significantly positively correlated with organic matter and negatively correlated with carbonate,
while in the core more distant from the entrance only Pb showed significant positive correlation with organic matter. Obtained
results indicated that, except for lead which was enriched in surface sediment, in the time of sampling (before the building
of the nautical marina) investigated area belonged to unpolluted areas. 相似文献
12.
Mustafa Gurhan Yalcin 《Environmental Geology》2009,58(1):119-129
Geochemical works were conducted on anthropogenically effective lithologic unit exposing along the Susanoglu coast in Mersin,
Turkey. For this purpose, beach sand sediments from 33 stations were collected and heavy metal and oxide concentrations were
analyzed. To determine the source of heavy metals (natural and anthropogenic), simple and multivariate statistical analyses
were applied. According to factor analysis, three factors were determined. The first factor consists of SiO2, Al2O3, Na2O, K2O, TiO2, Cr, Ni, Cu and Mo and total variance is explained with 27.502% and expressed as “natural process factor”. These elements (Cr, Ni, Cu, Mo) are closely associated with geogenic materials and came from same sources of ultrabasic
rocks (ophiolite). The second factor consists of CaO, MgO, TiO2, MnO, Ni, Pb, Zn and W and total variance is explained with 21.505% and expressed as “anthropogenic factor”. These elements (Pb, Zn, Cd, V, W) are anthropogenic and are mainly due to the effluent or industrial input/activities and
came from different sources of pollution in the study area. The third factor consists of Pb, Cd and Sb and total variance
is explained with 9.748% and expressed as “intermediate factor”. The factor analysis and the cluster analysis are in support of each other. Cr, Ni, Co, Cd, Hg and Mo concentrations are
greater than Turkish acceptable values and they show toxic effect. Al, Cu, Pb, Cd and Mo concentrations in beach sand deposits
in the Susanoglu coast are found as 1.44, 1.26, 1.21, 1.02 and 1.04 mg/kg and higher than those in Kızkalesi beach sands.
However, all other heavy metal contents are determined in low concentrations. 相似文献
13.
Mobility of Al, Co, Cr, Cu, Fe, Mn, Ni and V in sulphide-bearing fine-grained sediments exposed to atmospheric O2: an experimental study 总被引:1,自引:0,他引:1
Mats Åström 《Environmental Geology》1998,36(3-4):219-226
The major aim was to increase our knowledge on the behaviour of Al, Co, Cr, Cu, Fe, Mn, Ni and V in sulphide-bearing fine-grained
sediments exposed to atmospheric oxygen. Samples of this type of sediment collected in a previous investigation at eight sites
in western Finland were digested in HClO4-HNO3-HCl-HF at 200 °C and in HCl:HNO3:H2O at 95 °C (aqua regia), and subjected to extractions with ammonium acetate and hydrogen peroxide. Metals and S in the leachates
were determined with ICP-AES. The results of the chemical analyses are compared with previously reported experimental data.
The concentrations of Al and Fe in the sulphide-bearing fine-grained sediments are about 7% and 5%, respectively. Of the trace
metals studied, Mn is most abundant followed in decreasing order by V>Cr>Ni>Cu>Co. On oxidation of the sediments, high proportions
of Co, Mn and Ni, intermediate proportions of Cu but low proportions of Fe, Al, Cr and V are released. The extent of the release
of a metal on oxidation is controlled either by (1) the level to which the pH of the sediments drops on oxidation (Al, Cu,
Cr, V), (2) the amount of the metal associated with easily reduced phases (metal sulphides) in the sediments (Ni, Co) or (3)
the sum of the amount associated with reduced phases and adsorbed on soil compounds (Mn). No control of the release of Fe
on oxidation of the sediments was identified. Based on the results of the study it is argued that artificial drainage and
the subsequent oxidation of sulphide-bearing sediments will result in extensive leaching of Co, Mn and Ni, moderate leaching
of Cu and limited leaching of Cr and V into drainages. The major elements, Fe and Al, have the potential to be mobilised and
leached in large amounts, though the proportions mobilised/leached will remain low. It is suggested that the identification
of sulphide-bearing sediments with a high potential of metal release should be based on determination of metals in easily
mobilised reduced compounds (dissolved e.g. in H2O2) and of the level to which the pH of the sediments drops on oxidation.
Received: 16 October 1997 · Accepted: 9 March 1998 相似文献
14.
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
15.
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
16.
Serpentinite soils, common throughout the world, are characterized by low calcium-to-magnesium ratios, low nutrient levels and elevated levels of heavy metals. Yet the water quality and heavy metal concentrations in sediments of streams draining serpentine geology have been little studied. The aim of this work was to collect baseline data on the water quality (for both wet and dry seasons) and metals in sediments at 11 sites on the Marlborough Creek system, which drains serpentine soils in coastal central Queensland, Australia. Water quality of the system was characterized by extremely hard waters (555–698 mg/L as CaCO3), high dissolved salts (684–1285 mg/L), pH (8.3–9.1) and dissolved oxygen (often >110% saturation). Cationic dominance was Mg > Na > Ca > K and for anions HCO3 > Cl > SO4. Al, Cu and Zn in stream waters were naturally high and exceeded Australian and New Zealand Environment and Conservation Council guidelines. Conductivity displayed the highest seasonal variability, decreasing significantly after wet season flows. There was little seasonal variation in pH, which often exceeded regional guidelines. Stream sediments were enriched with concentrations of Ni, Cr, Co and Zn up to 35, 21, 10 and 2 times the world average for shallow sediments, respectively. Concentrations for Ni and Cr were up to 60 and 16 times those of the relevant Interim Sediment Quality Guidelines Low Trigger Values, respectively. The distinctive nature of the water and sediment data suggests that it would be appropriate to establish more localized water quality and sediment guidelines for the creek system for the water quality parameters conductivity, Cu and Zn (and possibly Cr and Cd also), and for sediment concentrations of Cd, Cr and Ni. 相似文献
17.
Heavy metals content and distribution in the surface sediments of the Guangzhou section of the Pearl River,Southern China 总被引:2,自引:2,他引:0
The long-term industrialization and urbanization of Guangzhou city may lead to heavy metal contamination of its aquatic sediment.
Nevertheless, only few studies have been published on the distribution and contamination assessment of heavy metals in this
urban river sediment. Thus, the major objective of this study was to quantitatively assess contamination of heavy metals and
their chemical partitioning in the sediments of the Guangzhou section of the Pearl River (GSPR). Surface sediment samples
were collected at 10 sites in the main river and 12 sites in the creeks of the GSPR. The total content of Cd was determined
by graphite furnace atomic adsorption spectrometry (GF-AAS), and content of Cr, Cu, Pb and Zn was determined by inductively
coupled plasma atomic emission spectrometry (ICP-AES). The chemical partitioning of these heavy metals in the sediments of
the main river was determined by the sequential selective extraction (SSE) method. Results indicated that the average total
concentrations of Cd, Cr, Pb, Cu and Zn in the sediments of the main river were 1.44, 63.7, 95.5, 253.6 and 370.0 mg/kg, respectively,
whereas they were 2.10, 125.5, 110.1, 433.7 and 401.9 mg/kg in the sediments of the creeks. The sediment at M4 and C9 sites
was heavily contaminated with about 8 and 11 of toxic unit, respectively. Cr, Cu, Pb and Zn were mostly bound to organic matter
and in the residual phase, whereas Cd was mostly associated with the soluble and exchangeable phase and the residual phase.
The mobility and bioavailability of Cd, Zn and Cr in the sediments of the main river were relatively higher than Cu and Pb,
due to higher levels in the soluble and exchangeable fraction and the carbonate fraction. The potential acute toxicity in
the sediments of the main river and creeks was mainly caused by Cu contamination, accounting for 21.7–37.1% and 16.9–46.3%
of the total toxicity, respectively, followed by Zn and Pb. Adverse biological effects induced by heavy metals would be expected
in the sediments of the GSPR. Therefore, the sediments of the GSPR, especially at M4 and C9 sites, need to be remediated to
maintain aquatic ecosystem health. 相似文献
18.
Distribution and speciation of heavy metals and their sources in Kumho River sediment,Korea 总被引:1,自引:1,他引:0
The interaction between heavy metals and river sediment is very important because river sediment is the sink for heavy metals
introduced into a river and it can be a potential source of pollutants when environmental conditions change. The Kumho River,
the main tributaries of the Nakdong River in Korea, can be one of the interesting research targets in this respect, because
it runs through different geologic terrains with different land use characteristics in spite of its short length. Various
approaches were used, including mineralogical, geochemical, and statistical analyses to investigate the distribution and behavior
of heavy metals in the sediments and their sources. The effect of geological factor on the distribution of these metals was
also studied. No noticeable changes in the species or relative amounts of minerals were observed by quantitative X-ray diffraction
in the sediments at different stations along the river. Only illite showed a significant correlation with concentrations of
heavy metals in the sediments. Based on an average heavy metal concentration (the average concentrations of Cd, Co, Cr, Cu,
Ni, Pb, and Zn were 1.67, 20.9, 99.7, 125, 97.6, 149, 298 ppm, respectively), the sediments of the Kumho River were classified
as heavily polluted according to EPA guidelines. The concentrations of heavy metals in the sediments were as follows: Zn > Pb > Cu > Ni > Cr > Co > Cd.
In contrast, contamination levels based on the average I
geo (index of geoaccumulation) values were as follows: Pb > Cd > Zn > Cu > Co = Cr > Ni. The concentrations of heavy metals increased
downstream (with the exception of Cd and Pb) and were highest near the industrial area, indicating that industrial activity
is the main factor in increasing the concentrations of most heavy metals at downstream stations. Sequential extraction results,
which showed increased heavy metal fractions bound to Fe/Mn oxides at the downstream stations, confirmed anthropogenic pollution.
The toxicity of heavy metals such as Ni, Cu, and Zn, represented by the exchangeable fraction and the fraction bound to carbonate,
also increased at the downstream stations near the industrial complexes. Statistical analysis showed that Pb and Cd, the concentrations
of which were relatively high at upstream stations, were not correlated with other heavy metals, indicating other possible
sources such as mining activity. 相似文献
19.
Geochemistry of Cu, Co, Ni, Zn, Cd and Cr in the surficial sediments of a tropical estuary, southwest coast of India: a granulometric approach 总被引:3,自引:0,他引:3
Geochemical characteristics of six trace metals – Cu, Co, Ni, Zn, Cd and Cr – in the bulk sediment and sand, silt and clay
fractions of a tropical estuary on the southwest coast of India have been studied and discussed. In bulk sediment, the trace
metal concentration is controlled mainly by the textural composition of the sample. Mud, sandy mud and sandy silt register
higher concentrations of trace metals than that in sand-dominant sediments. The granulometric partitioning studies also re-affirmed
the role of particle size in enriching the trace metals. The silt and clay fractions exhibit 7–8 times the enrichment of Cu
and Cd compared to that in sand. The enrichment factors of Zn, Cr, Ni and Co in the silt and clay fractions, compared to that
in sand, are 5–6, 4–5, 2–5 and 2–3 times, respectively. The trace metals in the sand fraction, particularly Ni and Cr, exhibit
strong positive correlation with the heavy mineral content of the samples. It clearly indicates a heavy mineral pathway to
the trace metals in the sand fraction. Cu and Co in silt and clay fractions exhibit a marked decrease towards the high saline
zones of the estuary. This is attributed to the desorption of Cu and Co from particulate phases during estuarine mixing. Contrary
to Cu and Co, the content of Zn in the clay fraction shows a marginal increase towards the estuarine mouth. This could be
explained by the influx of Zn-rich contaminant discharges from Zn-smelting industries located slightly north of the estuarine
mouth. The released Zn will effectively be held in the lattices of the clay mineral montmorillonite, which also exhibits a
marked increase towards the estuarine mouth. The anomalously high values of Cd in some places of the Central Vembanad estuary
is attributed to the local pollution.
Received: 10 July 1995 · Accepted: 3 June 1996 相似文献
20.
Source and distribution of trace metals and nutrients in Narmada and Tapti river basins,India 总被引:2,自引:1,他引:1
The study was designed to establish the distributions of trace metals, dissolved organic carbon, and inorganic nutrients as
well as to assess the extent of anthropogenic inputs into the Narmada and Tapti rivers. Water and sediment qualities are variable
in the rivers, and there are major pollution problems at certain locations, mainly associated with urban and industrial centers.
The metal concentrations of samples of the aquatic compartments investigated were close to the maximum permissible concentration
for the survival of aquatic life, except for higher values of Cu (5–763 μg l−1), Pb (24–376 μg l−1), Zn (24–730 μg l−1), and Cr (70–740 μg l−1) and for drinking water except for elevated concentrations of metals such as Pb, Fe (850–2,060 μg l−1), Cr, and Ni (20–120 μg l−1). In general, the concentrations of trace metals in the rivers vary down stream which may affect the “health” of the aquatic
ecosystem and may also affect the health of the rural community that depends on the untreated river water directly for domestic
use. The assessment of EF, I
geo, and PLI in the sediments reveals overall moderate pollution in the river basins. 相似文献