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1.
Vertical accretion rates and heavy metal chronologies in wetland sediments of the Tijuana Estuary 总被引:3,自引:0,他引:3
This study represents the first report on sediment accretion rates using137Cs dating for a southern California salt marsh. Vertical accretion rates ranged from 0.7 to 1.2 cm yr−1, which is at the high end of sediment accretion values for coastal wetlands. This has lead to increases in elevation within the estuary from 18 to 35 cm over the last 35 years. Depth profiles of metal concentrations were converted to time-based profiles using vertical accretion rates. Chronologies for most cores indicate a consistent peak in sediment lead (Pb) concentrations in the early to mid 1980s, corresponding to the historic decline in Pb use, which was completed in the U.S. by the early 1980s, but not begun in Mexico until 1991. Sediment Pb levels ranged from about 6–56 μg g−1. Other metals did not show any consistent trends in sediment chronology, except for a single core from a mid-marsh site (east-mid 2), which showed a 2–3-fold increase in levels of Cu, Ni, and Zn during the past two decades. Sediment levels of copper (Cu), nickel (Ni), and zinc (Zn) ranged from 6–34 μg g−1, 11–27 μg g−1, and 42–122 μg g−1, respectively. Despite rapid industrial development of the watershed, a comparison of the sediment metal concentrations in the Tijuana Estuary to other anthropogenically-impacted estuaries in the United States and Europe, shows that metal levels in sediments of the north arm of the estuary are relatively low. 相似文献
2.
Distribution of the trace elements Cr, Cu, Ni, Pb and Zn in surficial sediments of the river/sea environment in Danang –
Hoian area (Vietnam) was investigated to examine the degree of metal pollution caused by anthropogenic activities. Point sources
from domestic and industrial wastes are identified as dominant contributors of trace element accumulation. Surficial sediments
of Hoian River show extremely high total concentrations of Cu (Average Concentration 295 μg/g), Ni (AC 112 μg/g), Pb (AC 396 μg/g)
and Zn (AC 429 μg/g) that exceed assigned safety levels ER-M. Similarly, the sediments of Han River show high Pb (AC 188 μg/g)
and Zn (AC 282 μg/g) contents. In marine sediments of Thanhbinh beach Pb is also enriched (138 μg/g) above guideline levels.
In contrast the sediments of the Cude River are dominated by trace element concentrations close to background values.
Received: 17 December 1998 · Accepted: 6 May 1999 相似文献
3.
Trace elements contamination of agricultural soils affected by sulphide exploitation (Iberian Pyrite Belt,Sw Spain) 总被引:1,自引:0,他引:1
Agricultural soils of the Riotinto mining area (Iberian Pyrite Belt) have been studied to assess the degree of pollution by
trace elements as a consequence of the extraction and treatment of sulphides. Fifteen soil samples were collected and analysed
by ICP-OES and INAA for 51 elements. Chemical analyses showed an As–Cu–Pb–Zn association related with the mineralisation of
the Iberian Pyrite Belt. Concentrations were 19–994 mg kg−1 for As, 41–4,890 mg kg−1 for Pb, 95–897 mg kg−1 for Zn and of 27–1,160 mg kg−1 for Cu. Most of the samples displayed concentrations of these elements higher than the 90th percentile of the corresponding
geological dominium, which suggests an anthropogenic input besides the bedrock influence. Samples collected from sediments
were more contaminated than leptosols because they were polluted by leachates or by mining spills coming from the waste rock
piles. The weathering of the bedrock is responsible for high concentrations in Co, Cr and Ni, but an anthropogenic input,
such as wind-blown dust, seems to be indicative of the high content of As, Cu, Pb and Zn in leptosols. The metal partitioning
patterns show that most trace elements are associated with Fe amorphous oxy-hydroxides, or take part of the residual fraction.
According to the results obtained, the following mobility sequence is proposed for major and minor elements: Mn, Pb, Cd, > Zn,
Cu > Ni > As > Fe > Cr. The high mobility of Pb, Cu and Zn involve an environmental risk in this area, even in soils where
the concentrations are not so high. 相似文献
4.
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
5.
Assessment of heavy-metal contamination of floodplain soils due to mining and mineral processing in the Harz Mountains, Germany 总被引:9,自引:2,他引:7
2 study area was assessed with respect to its heavy-metal load on the basis of the current guideline values. The heavy-metal
loads of the soils in the study area have ranges of <0.2–200 mg kg−1 for Cd, <10–30,000 mg kg−1 for Pb, 7–10,000 mg kg−1 for Cu and 50–55,000 mg kg−1 for Zn. Mobility of the heavy metals was determined by extraction at different pH values. The acid neutralisation capacity
(ANCx) at these pH values was also determined to estimate the probability that the pH can drop to pH=x. The ANC values in the study area ranged from 6 to 3000 mmol H+ kg−1, from −33 to 800 mmol H+ kg−1 and from −74 to 160 mmol H+ kg−1 for ANC3.5, ANC5.0 and ANC6.2, respectively. Together with pedological data, the extraction experiments permit differentiation between soil units that
have been placed in the same environmental hazard class on the basis of total heavy-metal loads.
Received: 10 August 1998 · Accepted: 14 August 1999 相似文献
6.
Phillipe Monbet 《Estuaries and Coasts》2004,27(3):448-459
Cadmium (Cd) variations were investigated over an annual cycle (12 surveys between February 1998–January 1999) in the Morlaix
estuary (Brittany, France) in both the water column and the benthic compartment in relation to hydrological conditions. The
drainage basin of the Morlaix River estuary is predominantly agricultural in character. Dissolved Cd concentrations in the
water column varied from 0.04 to 0.48 nM. Particulate Cd concentrations ranged from 1 to 64 nmol g−1. These concentrations reach levels commonly observed in estuaries affected by heavy industrial activities. Extensive agricultural
activities in the drainage basin may be responsible for Cd levels above pristine conditions. Metal concentrations varied significantly
over the seasonal cycle and the dissolved fraction exhibited high values in summer months. Particulate concentrations were
always lowest during this season. In the benthic compartment, Cd concentrations in surface sediment varied from 0.4 to 5.0
nmol g−1 and from 0.2 to 5.0 nM in porewaters. Concentrations in sediment were slightly affected by Cd contamination and temporal
changes were important over the seasonal cycle. The variations seem to be controlled by the succession of sedimentation and
erosion processes, which are tightly linked to seasonal changes in river discharge. A box model was constructed based on known
Cd sources and sinks in the estuary. Cd is chiefly brought into the estuary by the Morlaix River and accumulates within the
estuary. The accumulation within the estuary represents from 6.3 to 7.2 kg yr−1. 相似文献
7.
Geochemical and statistical approach to evaluate background concentrations of Cd,Cu, Pb and Zn (case study: Eastern Poland) 总被引:2,自引:2,他引:0
Wojciech Zgłobicki Lesia Lata Andrzej Plak Marek Reszka 《Environmental Earth Sciences》2011,62(2):347-355
An attempt was made to evaluate background concentrations of Cd, Cu, Pb and Zn by means of geochemical and statistical approach.
As many as 753 samples taken from 51 profiles located in Eastern Poland were analysed. For the estimation of geochemical background
values, direct geochemical methods and a statistical analysis for the whole population of samples were applied. Average values
of heavy metal concentration in loess sediments (bedrock) as well as in profiles not affected by human activity were measured.
The iterative 2σ technique and calculated distribution function were chosen as statistical methods. The resulting values (background
concentrations range) were as follows: Cd 0.5–0.9 mg kg−1, Cu 5–16 mg kg−1, Pb 12–26 mg kg−1 and Zn 31–47 mg kg−1. All the methods applied gave similar results. The highest deviation of the background was noted for Cu and the lowest for
Zn. The lowest values of background were obtained for loess sediments and the highest in the case of the multiple 2σ method. 相似文献
8.
This study investigated physico-chemical characteristics of the water column and chemistry of suspended particulate material
(SPM) under quiescent, high-wind and high-wind/heavy-rainfall conditions in Homebush Bay, a highly contaminated embayment
of Port Jackson (Australia) to distinguish source and possible adverse effects to benthic and pelagic animals. Mean concentrations
in surficial sediment were <1, 14, 181, 141, 37, 290 and 685 μg g−1 for Cd, Co, Cr, Cu, Ni, Pb and Zn, respectively. Sediment chemistry indicated these metals had multiple sources, i.e. the
estuary, stormwater and industry. Mean total suspended solids (TSS) were 7, 17 and 20 mg L−1 during quiescent, high-rainfall and heavy rainfall/high wind conditions, respectively, whereas SPM Cd, Co, Cr, Cu, Ni, Pb
and Zn concentrations varied between 13–25, 166–259, 127–198, 38–82, 236–305 and 605–865 μg g−1, respectively under these conditions. TSS and total water metal concentrations were lowest during quiescent conditions. High
TSS and metal loads in surface water characterised high-rainfall events. Wind-induced resuspension contributed the greatest
mass of SPM and metals to the water column. Benthic animals may be adversely affected by Pb and Zn in sediment. Total water
Cu and Zn concentrations may pose a risk to filter-feeding animals in the water column due to resuspension of contaminated
sediment. 相似文献
9.
Water from the Kombat mine was delivered to the Omatako dam via the 263-km-long Grootfontein-Omatako canal during test runs
in 1997. It is intended to supply water from Kombat and other underground mines in the Otavi Mountain Land to the capital
Windhoek. The Cu-Pb-Zn orebodies are hosted by carbonate rocks and the mine waters are supersaturated with respect to calcite
and CO2. Along the length of the canal, the CO2 partial pressure drops from 10−2.1 atm at the inlet of the Kombat mine to 10−3.5 atm at the end of the canal. This is accompanied by a drop in Ca concentration from about 60 to about 20 mg/l. The heavy
metal concentrations (Cd, Cu, Mn, Pb and Zn) drop along the course of the canal to values far below the national drinking-water
standard. Scavenging by calcium carbonate precipitation is the major depletion mechanism.
Received: 21 June 1999 · Accepted: 29 August 1999 相似文献
10.
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
11.
Bed sediment-associated trace metals in an urban stream, Oahu, Hawaii 总被引:78,自引:0,他引:78
R. A. Sutherland 《Environmental Geology》2000,39(6):611-627
Of the 117 stream and lake systems sampled nationwide, fish from Manoa Stream on Oahu, Hawaii, have consistently shown the
highest Pb concentrations. Therefore a detailed study was conducted to examine total metal contents in bed sediments from
a 5.8-km stretch of Manoa Stream. A total of 123 samples (<63 μm) were examined for 18 elements and 14 samples for 21 elements.
Selected samples were also examined using different leach solutions to examine metal phase associations. All trace metal data,
computations of enrichment ratios and the modified index of geoaccumulation point to mineralogical control for Cr and Ni;
minor anthropogenic contamination for Ba, Cd, Cu, Hg and Zn; and a very strong contamination signal for Pb. Maximum Pb contents
(up to 1080 mg kg−1) were associated with anthropogenic material dumping in minor tributaries, storm sewer sediments and sediments in the “lower”
section of the basin. Proportionally Pb had the highest non-residual component of elements examined; dominantly in the reducible
phase associated with Mn and amorphous Fe oxyhydroxides. The contamination signal was typically lowest in the “undisturbed”
headwater reach of the basin (above 5.1 km) with significant increases throughout the “residential” and “commercial-institutional”
zones of the mid-basin. The spatial pattern of bed sediment contamination and evidence from storm sewer-outlet sediments strongly
indicates that Pb, and to a lesser degree some other metals, is still being transported to the stream and the primary agent
is soil erosion and transport of metals sorbed to sediments. The primary source of sediment-associated metals is considered
to be the automobile, though other minor sources can not be ruled out.
Received: 3 November 1998 · Accepted: 26 January 1999 相似文献
12.
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
13.
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
14.
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
15.
B. G. Lottermoser 《Environmental Geology》1998,36(1-2):118-126
Heavy metal and metalloid concentrations within stream-estuary sediments (<180-μm size fraction) in north-eastern New South
Wales largely represent natural background values. However, element concentrations (Ag, As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Zn)
of Hunter River sediments within the heavily industrialized and urbanized Newcastle region exceed upstream background values
by up to one order of magnitude. High element concentrations have been found within sediments of the Newcastle Harbour and
Throsby Creek which drains into urbanized and light industry areas. Observed Pb enrichments and low 208Pb/204Pb, 207Pb/204Pb and 206Pb/204Pb ratios are likely caused by atmospheric deposition of Pb additives from petrol and subsequent Pb transport by road run-off
waters into the local drainage system. Sediments of the Richmond River and lower Manning, Macleay, Clarence, Brunswick and
Tweed River generally display no evidence for anthropogenic heavy metal and metalloid contamination (Ag, As, Cd, Cr, Cu, Hg,
Ni, Pb, Sb, Zn). However, the rivers and their tributaries possess localized sedimentary traps with elevated heavy metal concentrations
(Cu, Pb, Zn). Lead isotope data indicate that anthropogenic Pb provides a detectable contribution to investigated sediments.
Such contributions are evident at sample sites close to sewage outlets and in the vicinity of the Pacific Highway. In addition,
As concentrations of Richmond River sediments gradually increase downstream. This geochemical trend may be the result of As
mobilization from numerous cattle-dip sites within the region into the drainage system and subsequent accumulation of As in
downstream river and estuary sediments.
Received: 5 September 1997 · Accepted: 4 November 1997 相似文献
16.
The thiol peptide phytochelatins (PC2; the polymer with n = 2) are efficient metal-chelating compounds produced by phytoplankton and higher plants. Both PC2 and their precursor glutathione
(GSH) are related to detoxification mechanisms. GSH and PC2 were quantified using liquid chromatography with fluorescent detection
and observed in the particulate phase along a salinity gradient of the Tamar Estuary (SW UK), a heavily metal impacted site,
at concentrations up to 274 and 16.5 μmol (g chl a)−1, respectively. The peptides predominated within low (0–5) and mid-salinities (5–20). Down-estuary, at sites farther from
metal sources and salinities higher than 20, PC2 showed a sharp decrease or were not detected. High PC2/GSH ratios indicated
areas with augmented concentrations of bioavailable metals at the tidal limit, near Cu mines and the mid-estuary where resuspension
of sediments occurs. By following typical partitioning patterns previously reported for dissolved Cu and Zn, the production
of thiol peptides, notably PC2, reflected a rapid interaction between the particulate and dissolved phases. 相似文献
17.
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
18.
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
19.
Eleven surface soil samples from calcareous soils of industrial areas in Hamadan Province, western Iran were analyzed for
total concentrations of Zn, Cd, Ni, Cu and Pb and were sequentially extracted into six fractions to determine the bioavailability
of various heavy metal forms. Total Zn, Cd, Ni, Cu and Pb concentrations of the contaminated soils were 658 (57–5,803), 125.8
(1.18–1,361), 45.6 (30.7–64.4), 29.7 (11.7–83.5) and 2,419 (66–24,850) mg kg−1, respectively. The soils were polluted with Zn, Pb, and Cu to some extent and heavily polluted with Cd. Nickel values were
not above regulatory limits. Copper existed in soil mainly in residual (RES) and organic (OM) fractions (about 42 and 33%,
respectively), whereas Zn occurred essentially as RES fraction (about 69%). The considerable presence of Cd (30.8%) and Pb
(39%) in the CARB fraction suggests these elements have high potential biavailability and leachability in soils from contaminated
soils. The mobile and bioavailable (EXCH and CARB) fractions of Zn, Cd, Ni, Cu, and Pb in contaminated soils averaged (7.3,
40.4, 16, 12.9 and 40.8%), respectively, which suggests that the mobility and bioavailability of the five metals probably
decline in the following order: Cd = Pb > Ni > Cu > Zn. 相似文献
20.
A. C. Ruiz-Fernández M. Frignani C. Hillaire-Marcel B. Ghaleb M. D. Arvizu J. R. Raygoza-Viera F. Páez-Osuna 《Estuaries and Coasts》2009,32(3):551-564
210Pb geochronologies of Cd, Cu, Hg, and Pb fluxes were obtained from the intertidal mudflat sediments of the coastal lagoons
Chiricahueto, Estero de Urías, and Ohuira in the Mexican Pacific. The Cu and Hg sediment concentrations at the three lagoons
fell within the ranges of 6–76 μg g−1 and 0.1 to 592 ng g−1, respectively; Chiricahueto and Estero de Urías sediments had comparable Cd and Pb concentrations within the ranges of 0.2–2.1 μg
g−1 and 10–67 μg g−1, respectively; whereas in Ohuira lagoon, Cd concentrations were lower (0.1–0.5 μg g−1) and Pb concentrations were higher (115–180 μg g−1) than in the other lagoons. The metal fluxes (μg cm−2 y−1) for the three lagoons fell within the ranges of 0.02–0.15 for Cd, 0.7–6.0 for Cu, 0.001–0.045 for Hg, and 0.7–20 for Pb.
The Hg pollution in Estero de Urías was attributed to the exhausts of the thermoelectric plant of Mazatlan and the metal enrichment
in Chiricahueto and Ohuira was related to the agrochemical wastes from the croplands surrounding these lagoons. 相似文献