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1.
The Sarcheshmeh copper mine smelter plant is one of the biggest copper producers in Iran. Long-time operation of about 25 years
of the smelter plant causes release of potentially toxic heavy metals into the environment. In this paper, geochemical distribution
of toxic heavy metals in 28 soil samples was evaluated around the Sarcheshmeh smelter plant. Soils developed over the nonmineralized
and uncontaminated areas have an average background concentration of 41.25 mg kg−1 Cu, 26.6 mg kg−1 As, 12.7 mg kg−1 Pb, 0.9 mg kg−1 Sb, 1.9 mg kg−1 Mo, 1.7 mg kg−1 Sn, 0.2 mg kg−1 Cd, 0.15 mg kg−1 Bi, 235 mg kg−1 S and 73.4 mg kg−1 Zn, respectively. As a result of smelting process, the upper soil layers (0–5 cm) were polluted by Cu (>1,397 mg kg−1), Cd (>3.42 mg kg−1), S (>821 mg kg−1), Mo (>10.3 mg kg−1), Sb (>11.7 mg kg−1), As (>120.6 mg kg−1), Pb (>83.8 mg kg−1), Zn (>214.9 mg kg−1), and Sn (>3.7 mg kg−1), respectively. These values are much higher than the normal concentration of the elements in the uncontaminated soil layers.
The elemental values decrease with distance travelled away of the smelter plant, especially at minimum wind direction. Furthermore,
high contaminated values of Cu (8,430 mg kg−1), As (500 mg kg−1), Pb (331 mg kg−1), Mo (61 mg kg−1), Sb (56.2 mg kg−1), Zn (664 mg kg−1), Cd (17.2 mg kg−1), Bi (13.4 mg kg−1), and S (3,780 mg kg−1) were observed in the upper soil layers close to the smelting waste dumps. Sequential extraction analysis shows that about
270 mg kg−1 Cu, 28 mg kg−1 Pb, 50.33 mg kg−1 Zn, and 47.84 mg kg−1 As were adsorbed by Fe and Mn oxides. The carbonate phases include 151 mg kg−1 Cu, 28 mg kg−1 Pb, 25 mg kg−1 Zn, and 32.99 mg kg−1 As. Organic matter adsorbed 314.6 mg kg−1 Cu and 29.18 mg kg−1 Zn. 相似文献
2.
P. Conde Bueno E. Bellido J. A. Martín Rubí R. Jiménez Ballesta 《Environmental Geology》2009,56(5):815-824
Mercury (Hg) is one of the elements with increasing environmental significance. A total of 22 samples (soils, rocks and gels)
were collected along a 6 km transect around the Valdeazogues River valley in the southwest of the Iberian Peninsula (Almadén,
Spain). Samples were characterized by different soil types of depositional sequences associated with mining tailings, type
and system tracts: 15 surface soil samples included in the transect; 3 of a Haploxerept soil profile developed on slates;
2 of quartzite and slates rocks (reference rocks in the area). Moreover, two of a gel substance (in the lower tract of the
river). Soil samples were analyzed for Hg, Cu, Ni, Cr, V, Pb, Cd and As, as well as for organic matter, pH abrasion and calcium
carbonate content. All samples were collected from the Almadén mining district. The level of occurrence of the elements (especially
Hg) and the effect of some properties on its concentration distributions were investigated. The total mercury contents varied
in the range 7,315–3.44 mg kg−1. The mean concentration of total mercury in soils and rocks was 477.03 mg kg−1dry mass. This value is very high compared to the regional background value of other areas. Only rarely is it higher than
1%: in one sample (7,315 mg kg−1) it was almost eight times in comparison with the affected zones, with a high value of 1,000 mg kg−1. Significant differences between samples were found in the total content of mercury. A large percentage of the samples registered
detectable levels of V, Cr, Ni, Pb, As and Cu. Cd readings were below the detectable range for all samples tested. Cr mean
concentration was 216.95 mg kg−1 (minimun concentration 86, maximun 358); V mean concentration was 119.09 mg kg−1 (minimun concentration 69, maximun 1,209); As mean concentration was 51.24 mg kg−1 (minimun 13.3 and maximun 319.4); Ni mean concentration was 45.64 mg kg−1 (minimun concentration 21.2 and maximun 125.6); Cu mean concentration was 33.25 mg kg−1 (minimun concentration 19.3 and maximun 135); Pb mean concentration was 15.19 mg kg−1 (minimun 1.12 and maximun 1013). Metal distribution generally showed spatial variability ascribed to significant anthropogenic
perturbation by mining tailing type. Hg showed vertical profile characterized by surface enrichment, with concentrations in
the upper layer (93.7–82.2 mg kg−1 in front of 3.4 of the rock value) exceeding, in several occasions, the background value. The results obtained denote a potential
toxicity of some heavy metals in some of the studied samples. Water-soluble mercury could enter the aquatic system and accumulate
in sediments. Mercury and other heavy metals contamination depended on the duration and intensity of mining activities. 相似文献
3.
Fluorine is one of the many environmental harmful elements released by volcanic activity. The content of total oxalate-extractable
and water-extractable fluorine was determined in 96 topsoils of three active volcanic systems of southern Italy (Mt Etna,
Stromboli and Vulcano). Total fluorine (F) content (F
TOT) ranges from 112 to 7,430 mg kg−1, F extracted with oxalate (F
OX) ranges from 16 to 2,320 mg kg−1 (2–93% of F
TOT) and F extracted with distilled water (
) ranges from 1.7 to 159 mg kg−1 (0.2–40 % of F
TOT). Fluorine in the sampled topsoils derives both from the weathering of volcanic rocks and ashes and from the enhanced deposition
due to volcanic gas emissions either from open-conduit passive degassing (Mt Etna and Stromboli) or from a fumarolic field
(Vulcano). Fluorine accumulation in the studied soils does not generally present particular environmental issues except for
a few anomalous sites at Vulcano, where measured contents could be dangerous both for vegetation and for grazing animals. 相似文献
4.
Rohit Mehra Sandeep Kumar Rajendra Sonkawade N. P. Singh Komal Badhan 《Environmental Earth Sciences》2010,59(5):1159-1164
The activity concentration and the gamma-absorbed dose rates of the terrestrial naturally occurring radionuclides (232Th, 226Ra and 40K) were determined in soil samples collected from ten different locations of Sirsa district of Haryana, using HPGe detector
based on high-resolution gamma spectrometry system. The range of activity concentrations of 226Ra, 232Th and 40K in the soil samples from the studied areas varies from 19.18 Bq kg−1 (Moriwala) to 40.31 Bq kg−1 (Rori), 59.43 Bq kg−1 (Pipli) to 89.54 Bq kg−1 (Fatehpur) and 223.22 Bq kg−1 (Moriwala) to 313.32 Bq kg−1 (SamatKhera) with overall mean values of 27.94, 72.75 and 286.73 Bq kg−1 respectively. The absorbed dose rate calculated from activity concentration of 226Ra, 232Th and 40K ranges between 8.84 and 18.58, 37.02 and 55.78, and 9.24 and 12.97 nGy h−1, respectively. The total absorbed dose in the study area ranges from 60.40 to 82.15 nGy h−1 with an average value of 70.12 nGy h−1. The calculated values of external hazard index (H
ex) for the soil samples of the study area range from 0.36 to 0.49 with an average value of 0.42. 相似文献
5.
Hyperaccumulation of lead,zinc, and cadmium in plants growing on a lead/zinc outcrop in Yunnan Province,China 总被引:3,自引:0,他引:3
A field survey was conducted to identify potential hyperaccumulators of Pb, Zn or Cd in the Beichang Pb/Zn mine outcrop in
Yunnan Province, China. The average total concentrations of Pb, Zn, and Cd in the soils were up to 28,438, 5,109, and 52 mg kg−1, respectively. A total of 68 plant species belonging to 60 genera of 37 families naturally colonizing the outcrop were recorded.
According to metal accumulation in the plants and translocation factor (TF), Silene viscidula was identified as potential hyperaccumulator of Pb, Zn, and Cd with mean shoot concentrations of 3,938 mg kg−1 of Pb (TF = 1.2), 11,155 mg kg−1 of Zn (TF = 1.8) and 236 mg kg−1 of Cd (TF = 1.1), respectively; S. gracilicanlis (Pb 3,617 mg kg−1, TF = 1.2) and Onosma paniculatum (Pb 1,837 mg kg−1, TF = 1.9) were potential Pb hyperaccumulators. Potentilla griffithii (Zn 8,748 mg kg−1, TF = 1.5) and Gentiana sp. (Zn 19,710 mg kg−1, TF = 2.7) were potential Zn hyperaccumulators. Lysimachia deltoides (Cd 212 mg kg−1, TF = 3.2) was a potential Cd hyperaccumulator. These new plant resources could be used to explore the mechanisms of Pb,
Zn and/or Cd hyperaccumulation, and the findings could be applied for the phytoremediation of Pb, Zn and/or Cd-contaminated
soils. 相似文献
6.
Mohsen Jalali 《Environmental Geology》2007,53(2):365-374
Phosphorus (P) application in excess of plant requirement may result in contamination of drinking water and eutrophication
of surface water bodies. The phosphorous buffer capacity (PBC) of soil is important in plant nutrition and is an important
soil property in the determination of the P release potential of soils. Phosphorus sorption greatly affects both plant nutrition
and environmental pollution. For better and accurate P fertilizer recommendations, it is necessary to quantify P sorption.
This study was conducted to investigate available P and P sorption by calcareous soils in a semi-arid region of Hamadan, western
Iran. The soil samples were mainly from cultivated land. Olsen’s biocarbonate extractable P (Olsen P) varied among soils and
ranged from 10 to 80 mg kg−1 with a mean of 36 mg kg−1. Half of the soils had an Olsen P > 40 mg kg−1 and >70% of them had a concentration >20 mg kg−1, whereas the critical concentration for most crops is <15 mg P kg−1. Greater average Olsen P in soils occurred under garlic (56 mg kg−1) and potato (44 kg kg−1) fields than in dry-land wheat farming (24 mg kg−1), pasture (30 mg kg−1), and wheat (24 mg P kg−1) fields. A marked increase in fertilizer P rates applied to agricultural soils has caused P to be accumulated in the surface
soil. Phosphate sorption curves were well fitted to the Freundlich equation. The standard P requirement (SPR) of soils, defined
as the amount of P sorbed at an equilibrium concentration of 0.2 mg l−1 ranged from 4 to 102 mg kg−1. Phosphorus buffer capacity was relatively high and varied from 16 to 123 l kg−1 with an average of 58 l kg−1. In areas of intensive crop production, continual P applications as P fertilizer and farmyard manure have been used at levels
exceeding crop requirements. Surface soil accumulations of P are high enough that loss of P in surface runoff and a high risk
for P transfer into groundwater have become priority management concerns. 相似文献
7.
The groundwaters from Zhongxiang City, Hubei Province of central China, have high fluoride concentration up to 3.67 mg/L,
and cases of dental fluorosis have been found in this region. To delineate the nature and extent of high fluoride groundwaters
and to assess the major geochemical factors controlling the fluoride enrichment in groundwater, 14 groundwater samples and
5 Quaternary sediment samples were collected and their chemistry were determined in this study. Some water samples from fissured
hard rock aquifers and Quaternary aquifers have high fluoride concentrations, whereas all karst water samples contain fluoride
less than 1.5 mg/L due to their high Ca/Na ratios. For the high fluoride groundwaters in the fissured hard rocks, high HCO3
− concentration and alkaline condition favor dissolution of fluorite and anion exchange between OH− in groundwater and exchangeable F− in some fluoride-bearing minerals. For fluoride enrichment in groundwaters of Quaternary aquifers, high contents of fluoride
in the aquifer sediments and evapotranspiration are important controls. 相似文献
8.
The source of fluoride toxicity in Muteh area,Isfahan, Iran 总被引:1,自引:0,他引:1
Behnam Keshavarzi Farid Moore Ali Esmaeili Fatemeh Rastmanesh 《Environmental Earth Sciences》2010,61(4):777-786
Endemic dental fluorosis has been observed in most inhabitants of three villages of Muteh area, located in northwest of Isfahan
province, with mottled enamel related to high levels of fluoride in drinking water (1.8–2.2 ppm). Forty-seven groundwater
samples from six villages were collected and fluoride concentrations along with physico-chemical parameters were analyzed.
Fluoride concentration in this area varies from 0.2 to 9.2 mg/l with highest fluoride level at Muteh gold mine (Chahkhatun
mine). Fluoride concentration positively correlates with pH and HCO3
− indicating that alkaline pH provides a suitable condition for leaching of fluoride from surrounding rocks. The district is
mainly covered by three lithological units, namely, metamorphic and granite rocks, alluvial sediments, and carbonate rocks.
Factor analysis shows that parameters can be classified into four components: electrical conductivity (EC), total dissolved
solids (TDS), Cl−, Na+ and K+, pH and F−, SO4
2−and Mg2+, HCO3
− and Ca2
+. The groundwaters from the three geological units were compared using Mann–Whitney U test. The order of median fluoride concentration is: metamorphic and granite rocks > alluvial sediments > carbonate rocks.
Hence, the fluoride content is most probably related to fluoride-bearing minerals such as amphibole and mica group minerals
in metamorphic and granitic rocks. The concentration of fluoride in drinking water wells located near the metamorphic complex
in Muteh area is above 2 ppm. 相似文献
9.
The Cu–Co–Ni Texeo mine has been the most important source of Cu in NW Spain since Roman times and now, approximately 40,000 m3 of wastes from mine and metallurgical operations, containing average concentrations of 9,263 mg kg−1 Cu, 1,100 mg kg−1 As, 549 mg kg−1 Co, and 840 mg kg−1 Ni, remain on-site. Since the cessation of the activity, the abandoned works, facilities and waste piles have been posing
a threat to the environment, derived from the release of toxic elements. In order to assess the potential environmental pollution
caused by the mining operations, a sequential sampling strategy was undertaken in wastes, soil, surface and groundwater, and
sediments. First, screening field tools were used to identify hotspots, before defining formal sampling strategies; so, in
the areas where anomalies were detected in a first sampling stage, a second detailed sampling campaign was undertaken. Metal
concentrations in the soils are highly above the local background, reaching up to 9,921 mg kg−1 Cu, 1,373 mg kg−1 As, 685 mg kg−1 Co, and 1,040 mg kg−1 Ni, among others. Copper concentrations downstream of the mine works reach values up to 1,869 μg l−1 and 240 mg kg−1 in surface water and stream sediments, respectively. Computer-based risk assessment for the site gives a carcinogenic risk
associated with the presence of As in surface waters and soils, and a health risk for long exposures; so, trigger levels of
these elements are high enough to warrant further investigation. 相似文献
10.
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
11.
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
12.
Copper contamination in soils and vegetables in the vicinity of an abandoned copper mine in China was investigated. The Cu
concentrations of 93 soil samples ranged from 30.4 to 3,191 mg kg−1 soil for a mean of 816.8 mg kg−1 soil. Among 15 samples from a 0 to 20-cm soil layer used for the toxicity characteristic leaching procedure (TCLP) test,
the highest value of Cu-TCLP was 133.8 mg kg−1 soil and the TCLP values were positively correlated with the total Cu content of the soils. The sequential extraction of
soils in the 0–20-, 20–40-, and 40–60-cm soil layers showed that Cu existed mainly in the Fe–Mn oxide fraction, sulfide/organic
fraction, and residual fraction. The copper contamination of 21 species of vegetables from in situ sampling was also examined.
Cu concentrations in the edible portions of Brassica chinensis and Solanum melongena were higher than the FAO/WHO standard (40 mg kg−1 DW). The health risk of copper for local inhabitants from consuming these vegetables was assessed on the basis of the target
hazard quotient. Enriched concentrations of copper were also found in situ in eight cultivars of B. chinensis planted in the fields, with two levels of Cu concentration. The results showed that there is severe copper contamination
in this mine area, and the pollutant in soils show a high risk of leaching into the groundwater and diffusing through the
food chain. 相似文献
13.
R. E. Masto L. C. Ram P. R. Shandilya S. Sinha J. George V. A. Selvi 《Environmental Earth Sciences》2011,64(4):1107-1115
Coal handling, crushing, washing, and other processes of coal beneficiation liberate coal particulate matter, which would
ultimately contaminate the nearby soils. In this study, an attempt was made to determine the status of soil bio-indicators
in the surroundings of a coal beneficiation plant, (in relation to a control site). The coal beneficiation plant is located
at Sudamudih, and the control site is 5 km away from the contaminated site, which is located in the colony of Central Institute
of Mining and Fuel Research Institute, Digwadih, Dhanbad. In order to estimate the impact of coal deposition on soil biochemical
characteristics and to identify the most sensitive indicator, soil samples were taken from the contaminated and the control
sites, and analyzed for soil organic carbon (SOC), soil N, soil basal respiration (BSR), substrate-induced respiration (SIR),
and soil enzymes like dehydrogenase (DHA), catalase (CAT), phenol oxidase (PHE), and peroxidase (PER). Coal deposition on
soils improved the SOC from 10.65 to 50.17 g kg−1, CAT from 418.1 to 804.11 μg H2O2 g−1 h−1, BSR from 8.5 to 36.15 mg CO2–C kg−1 day−1, and SIR from 24.3 to 117.14 mg CO2–C kg−1 day−1. Soils receiving coal particles exhibited significant decrease in DHA (36.6 to 4.22 μg TPF g−1 h−1), PHE (0.031 to 0.017 μM g−1 h−1), PER (0.153 to 0.006 μM g−1 h−1), and soil N (55.82 to 26.18 kg ha−1). Coal depositions significantly (P < 0.01) decreased the DHA to 8.8 times, PHE to 1.8 times, and PER to 25.5 times, but increased the SOC to 4.71 times, CAT
to 1.9 times, SIR to 4.82 times, and BSR to 4.22 times. Based on principal component analysis and sensitivity test, soil peroxidase
(an enzyme that plays a vital role in the degradation of the aromatic organic compounds) is found to be the most important
indicator that could be considered as biomarkers for coal-contaminated soils. 相似文献
14.
Drinking water quality in villages of southwestern Haryana,India: assessing human health risks associated with hydrochemistry 总被引:1,自引:0,他引:1
Vinod K. Garg Surindra Suthar Sushma Singh Aleenjeet Sheoran Garima Meenakshi Sandeep Jain 《Environmental Geology》2009,58(6):1329-1340
The chemical quality of groundwater of western Haryana, India was assessed for its suitability for drinking purposes. A total
of 275 water samples were collected from deep aquifer based hand-pumps situated in 37 different villages/towns of Bhiwani
region. The water samples were analyzed for different physico-chemical properties, e.g., pH, total dissolved solids (TDS),
total harness (TH), total alkalinity (TA), calcium, magnesium, carbonate, bicarbonate, sulphate, chloride and fluoride concentrations.
In this study, the average TDS content was greater ranging 1,692 (Bhiwani block) to 2,560 mg l−1 (Siwani block), and other important parameters of water, e.g., TA (442–1,232 mg l−1), TH (437–864 mg l−1) and bicarbonate (554–672 mg l−1), were also higher than maximum permissible limit by WHO or BIS. The fluoride appeared as a major problem of safe drinking
water in this region. We recorded greater fluoride concentration, i.e., 86.0 mg l−1 from Motipura village that is highest fluoride level ever recorded for Haryana state. The average fluoride concentration ranged between
7.1 and 0.8 mg l−1 in different blocks of western Haryana. On the basis of fluoride concentration, Siwani block showed the maximum number of water samples (84% of total collected samples) unsuitable for drinking purposes (containing
fluoride >1.5 mg l−1) followed by Charki Dadri block (58%), Bhiwani block (52%), Bawani Khera block (33%) and Loharu block (14%). This study clearly suggest that some health deteriorating chemicals in drinking water were at dangerous level and;
therefore, water quality could be a major health threat for local residents of western Haryana. The high fluoride level in
drinking water has posed some serious dental health risks in local residents. 相似文献
15.
Kanchan Wakadikar Avik Sil Niranjan Kolekar Shalini Tandon Rakesh Kumar 《Environmental Earth Sciences》2011,64(1):25-28
Drilling fluids are used for drilling natural gas, oil and water wells. These spill over into the surrounding soil at the
point of drilling, which may impair soil health. A laboratory investigation was carried out to determine the effect of non
aqueous drilling fluid (NADF) and synthetic base oil used with it on soil health as indicated by the dehydrogenase activity.
A non-sterile sandy loam soil was treated with different amounts of NADF and base oil at a rate of 800, 8,000 and 16,000 mg kg−1. Initially, reduction in dehydrogenase activity was observed, but it increased with the incubation time. On the 60th day
of incubation dehydrogenase activity in untreated control was 1.04 mg TPF g−1 h−1 whereas in the soil samples treated with NADF and the base oil (16,000 mg kg−1), the activity was 1.53 mg TPF h−1 and 1.90 mg TPF h−1, respectively, which was 72 and 82% more than in untreated control. Base oil-treated soil showed more dehydrogenase activity
than that observed with NADF. Both NADF and base oil stimulated the soil dehydrogenase activity. 相似文献
16.
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
17.
Heavy metal concentrations and their possible sources in paddy soils of a modern agricultural zone,southeastern China 总被引:5,自引:0,他引:5
In a typical modern agricultural Zone of southeastern China, Haining City, 224 topsoil samples were collected from paddy fields
to measure the total concentrations of copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr), mercury (Hg), arsenic
(As) and cobalt (Co). The total concentrations ranged from 15.30 to 78.40 mg kg−1 for Cu, 20.10 to 41.40 mg kg−1 for Pb, 54.98 to 224.4 mg kg−1 for Zn, 0.04 to 0.24 mg kg−1 for Cd, 54.90 to 197.1 mg kg−1 for Cr, 0.03 to 0.61 mg kg−1 for Hg, 3.44 to 15.28 mg kg−1 for As, and 7.17 to 19.00 mg kg−1 for Co. Chemometric techniques and geostatistics were utilized to quantify their spatial characteristics and define their
possible sources. All eight metals had a moderate spatial dependency except that Pb had a strong spatial dependency. Both
factor analysis and cluster analysis successfully classified the eight metals into three groups or subgroups, the first group
included Cu, Zn and Cr, the second group included Cd, As and Co, and the last group included Pb and Hg. The Cu, Zn and Cr
concentrations in majority samples were higher than their local background concentrations and they were highly correlated
(r > 0.80), indicating that they had similar pollution source and anthropic factor controlled their spatial distribution; the
Cd, As and Co concentrations in majority samples were lower than their local background concentrations, indicating that the
source of these elements was mainly controlled by natural factors; the mean concentration of Pb exhibited generally low level,
close to its local background concentration, the Hg concentration in about half of samples was higher than its local background
concentration, and they were poor correlated with the other metals, indicating that the source of Pb and Hg was common controlled
by natural factor and anthropic factor. 相似文献
18.
Guo-Ping Wang Xiao-Fei Yu Jian Wang Hong-Mei Zhao Kun-Shan Bao Xian-Guo Lu 《Environmental Earth Sciences》2011,62(1):207-216
The rare earth elements (REEs) in the sediments of the Xianghai wetlands were measured by inductively coupled plasma spectrometry.
The REEs accumulation rates in two sedimentation cores derived from the riparian and depressional marshes were determined
by 210Pb method. The results showed that REEs concentrations in the Xianghai wetland sediments (∑REEs, 116 mg kg−1) were lower than the corresponding values in Chinese soils (181 mg kg−1) and river sediments (∑REEs, 158–191 mg kg−1). Under alkaline conditions (with pH, 8.2–10.3), the light REEs were more enriched than the heavy REEs. Cerium is the predominant
element, and accounts for 30–33% of the total REEs. REEs in the depressional marsh sediments were relatively high (∑REEs,
127 vs. 104 mg kg−1), especially light REEs contents. A significantly positive correlation was found between the neighboring elements except
Pr and Dy. The different types of vertical distribution of REEs between the riparian and the depressional marsh can partly
result from long-term differing hydrological regimes. Generally, depressional marsh had accumulated much more REEs than riparian
marsh (the mean accumulation rates of ∑REEs, 102.98 vs. 48.89 μg cm−2 year−1). 相似文献
19.
Cesium and Strontium concentrations were analyzed in eight pedogenetic soil profiles developed on different rocks from a semiarid
mediterranean region: La Mancha (Central Spain). Concentration activities of 137Cs and 90Sr, as for some soil properties, were also measured. The results are presented in this document: Cs concentrations range between
0.4 and 18.3 mg kg−1 and Sr varies widely between 11.0 and 3,384 mg kg−1. Therefore, it is clear that there is a broad range of concentrations and there are also values significantly higher than
the average values stated by several authors. Concentrations of long-life artificial radionuclides (137Cs, 90Sr) were determined in some of the same soils. The activity concentration mean values (Bq kg−1) were ranging between 0.82 and 21.76 for 137Cs and 90Sr variations range between 6.73 and 0.35. There were no significant correlations between radionuclides and stable trace elements.
The data indicate that the soils do not show significant radioactivity of these elements and therefore they do not pose a
danger. By the same token, no risk of contamination by this activity was detected. Finally, spatial patterns seem to be affected
by the soil type and some soil properties. 相似文献
20.
M. M. Saç E. Yumurtaci G. Yener B. Camgöz A. Uğur B. Özden 《Environmental Geology》2008,55(3):477-483
Gediz Basin is one of the regions where intense agricultural activities take place in Western Turkey. Erosion and soil degradation
have long been causing serious problems to cultivated fields in the basin. This work describes the application of two different
137Cs models for estimating soil erosion rates in cultivated sites of the region. Soil samples were collected from five distinct
cultivated regions subject to soil erosion. The variations of 137Cs concentrations with depth in soil profiles were investigated. Soil loss rates were calculated from 137Cs inventories of the samples using both proportional model (PM) and simplified mass balance model (SMBM). When PM was used,
erosion and deposition rates varied from −15 to −28 t ha−1 year−1 and from +5 to +41 t ha−1 year−1, respectively; they varied from −16 to −33 t ha−1 year−1 and from +5 to +55 t ha−1 year−1 with SMBM. A good agreement was observed between the results of two models up to 30 t ha−1 year−1 soil loss and gain in the study area. Ulukent, a small representative agricultural field, was selected to compare the present
data of 137Cs techniques with the results obtained by universal soil loss equation (USLE) applied in the area before. 相似文献