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1.
In this study the effect of anthropogenic discharges on the heavy metal content in the Potengi–Jundiai river system near the
fast growing city of Natal, NE-Brazil, is investigated. Due to the multiple anthropogenic source character without any predominating
anthropogenic heavy metal discharge the area of Natal may serve as a characteristic place for the study of the impact of the
fast growing Brazilian cities on the environment. In general the sediments of the Rio Potengi–Jundiai river system in the
studied area are not severely polluted. However, close to waste water drain pipes a characteristic anthropogenic heavy metal
signature is visible in enhanced Zn, Pb, Cu and Cd values relative to reference elements such as Al and Fe. Sources are domestic
and animal waste, combustion products and hydrocarbons. These heavy metals are probably mainly bound to organic matter. The
elements Sn, Hg and Ag in part also belong to the anthropogenic heavy metal signature. The elements Cr, Ni and V are characteristic
of weathering heavy minerals in crystalline rocks exposed in the catchment area of the river system and are not significantly
added from anthropogenic sources. These heavy metals are most likely predominantly bound to oxides and represent the pristine
geogenic background of the system. They can thus be used as reference elements to monitor incipient accumulation of Zn, Pb,
Cu and Cd due to anthropogenic input. The element characteristics found here match with those found in other fast growing
urban areas such as the Sao Paulo metropolitan area. 相似文献
2.
Industrial emissions are the major sources of heavy metal pollutions. This study investigates the anthropogenic contribution of heavy metal accumulation surrounding an industrial town in China, using the component partition method. Results show that Cu, Ni, Pb, and As have higher concentrations compared with their background levels and the industrial town has a significant impact on heavy metal accumulations in its surrounding agricultural soil. Prevailing wind direction may explain the difference of heavy metal concentration in different directions. Anthropogenic components of Cu, Ni, Pb and As, which decrease with distance following exponential functions, account for 11.4%, 6.2%, 18.5% and 7.9% of their total concentrations, respectively. The natural components are modeled as the functions of physico-chemical variables through multiple regressions. The accumulating processes of heavy metals affected by industrial activities could be explained by anthropogenic and natural components, and thus, it could provide basic information for further simulation of heavy metal accumulations. 相似文献
3.
The southernmost occurrence of the early Maastrichtian larger benthic foraminifera (LBF) in Tethys is known from the Kallankuruchchi Formation in the Cauvery Basin, SE India, represented by Lepidorbitoides-Siderolites assemblages. The systematics, age and paleobiogeography of Lepidorbitoides here have as yet remained unresolved due to lack of information particularly on the nepionic arrangement, whereas their links with the Western Tethyan and Caribbean biogeographic domains were speculated. Lepidorbitoides, studied from the same level in seven samples in two separate areas, invariably possess quadriserial nepionts and adauxiliary chamberlets, whose mean number ranges from 3.79 to 4.67. The ratio between the sample means of the internal diameter of deuteroconch and protoconch varies between 1.72 and 1.86. The equatorial layer in the early stage consists of arcuate chambers with basal stolons, and ogival-to spatulate chamberlets with annular and oblique stolons in the later stages. These features are consistent with the phylogenetically advanced members of the Western Tethyan Lepidorbitoides lineage, such as L. minor (Schlumberger) and L. socialis (Leymerie), and all samples were assigned to the transitional development stages of these species based on the morphometry. The taxonomic status of some Lepidorbitoides species, originally described from the Kallankuruchchi Formation and widely adopted in previous works, such as L. blanfordi (Rao) and L. inornata (Rao), are not justified. We extend the geographic range of Western Tethyan Lepidorbitoides to southern India. 相似文献
4.
P. J. Henderson I. McMartin G. E. Hall J. B. Percival D. A. Walker 《Environmental Geology》1998,34(1):39-58
Trace element geochemistry of humus (<0.425 mm) and till (<0.002 mm) collected in the Flin Flon-Snow Lake area, northern
Manitoba and Saskatchewan, provides a regional context for assessing smelter contamination in the environment. The area includes
a Cu-Zn smelter known to discharge As, Cd, Cu, Fe, Hg, Pb, and Zn. In this study, sequential extraction analyses, scanning
electron microscopy and x-ray diffraction analyses were used on a suite of samples to determine: (1) the chemical and physical
characteristics of heavy metals in surficial sediments related to distance from the smelter, (2) criteria for assessing the
relative contribution of these metals from natural and anthropogenic sources, and (3) the potential of these metals for remobilization
in the environment.
Humus geochemistry reflects the anthropogenic and natural component of heavy metal concentrations. Smelter-related elements
show anomalously high values adjacent to the smelter, decreasing with distance until background values are reached at 70–104 km,
depending on the element. In humus, Zn is associated primarily with labile phases; Hg with non-labile phases. Adjacent to
the smelter, high proportions and concentrations of Zn and Hg in non-labile phases, indicative of smelter-derived particulates,
are confirmed by SEM examination. The particles occur as spheres, irregular grains, and with organics. With increasing distance
from the smelter, the geochemical response to bedrock composition is more obvious than the anthropogenic input.
Till geochemistry reflects the natural variation imposed by bedrock composition. At highly contaminated sites (<3 km from
the smelter), increased percentages of smelter-related elements in labile phases suggests heavy metals are leached from humus
to the underlying sediment.
Received: 5 November 1996 · Accepted: 31 March 1997 相似文献
5.
6.
江西德兴铜矿大坞河土壤重金属累积特征与成因 总被引:1,自引:0,他引:1
江西德兴铜矿是中国超大型斑岩铜矿,随着矿业活动的增加,德兴铜矿区重金属污染问题日益严重。查明德兴铜矿土壤重金属累积作用及原因,可为政府机构、矿山开展环境整冶提供科学依据。在大坞河上游、中游、下游选定3个剖面,采集50件土壤样品,得出其基于地球化学基线的累积特征。整体来讲,Cu、Mo累积作用最为显著,Cr、As累积作用明显,同时发现一级、二级阶地上累积显著,并从矿石组合、地化背景、河流阶地、元素形态、矿山生产等角度开展累积作用的原因分析。 相似文献
7.
8.
Dreissena polymorpha is an exotic freshwater bivalve species which was introduced into the Great Lakes system in the fall of 1985 through the release
of ballast water from European freighters. Utilizing individual growth rings of the shells, the stable isotope distribution
(δ18O and δ13C) was determined for the life history of selected samples which were collected from the western basin of Lake Erie. These
bivalves deposit their shell in near equilibrium with the ambient water and thus reflect any annual variation of the system
in the isotopic records held within their shells. Observed values for δ18O range from -6.64 to –9.46‰ with an average value of –7.69‰ PDB, while carbon values ranged from –0.80 to –4.67‰ with an
average value of –1.76‰ PDB. Dreissena polymorpha shells incorporate metals into their shells during growth. Individual shell growth increments were analyzed for Pb, Fe, Mg,
Mn, Cd, Cu, and V concentrations. The shells show increased uptake of certain metals during periods of isotopic enrichment
which correspond with warmer water temperatures. Since metals are incorporated into the shells, the organism may be useful
as a biomonitor of metal pollution within aquatic environments.
Received: 31 October 1996 · Accepted: 21 May 1997 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.
研究评价不同粒级组分中重金属的活性和潜在环境风险,对3个地区土壤颗粒的分析表明,重金属在土壤中分布并不均匀,随着颗粒粒径的减小,重金属Cu、Cd元素及有机质的浓度有不断增高的趋势。线性分析显示,Cu、Cd元素浓度与有机质的浓度显著相关。形态分析表明,Cd主要以环境高活性的形态存在,其次以低活性的形态存在,环境惰性的形态仅占极小部分,Cu主要以低环境活性和环境惰性的形态存在,高环境活性的形态只占小量,Cu在土壤中的存在形态可能与土壤性质有关。 相似文献
11.
Sorption is an important process in the modelling and prediction of the movement of heavy metals in unsaturated clay barriers. This experimental study investigates the effect of pH changes in the acidic range on the sorption characteristics of heavy metals such as: lead, copper and zinc in an unsaturated soil. A series of one-dimensional coupled solute and moisture leaching column tests, using different heavy metal solutions, were conducted on an unsaturated illitic soil at varying pH values. Variations of volumetric water content (VWC) with distance were measured for different time durations, and concentrations of heavy metals in the liquid and solid phases were analysed. Partitioning coefficient profiles of contaminants along the soil column were determined for each individual layer in the soil.
Results from column leaching tests showed that the sorption characteristics of heavy metals are controlled by many factors which should be taken into consideration, i.e. the VWC, time of wetting, soil pH, and the influent heavy metal concentrations. Simplification of Kd as a constant and of the VWC as a linear function cannot be considered a good assumption and may lead to an improper evaluation of the sorption phenomena and also to serious errors in predicting contaminant transport through unsaturated soils. 相似文献
12.
The estuary of Odiel and Tinto rivers, located on the southwestern coast of the Iberian Peninsula, receives acidic fluvial
water discharges with high concentrations of sulphates and heavy metals from these rivers. In addition, a big industrial complex
which efflues directly on the system is located in the same estuary. The effluents induce the presence in the estuary of high
concentrations of heavy metals and phospates (nutrients). The application of factorial analysis techniques on the nutrients
and heavy metal concentrations in 46 water samples taken from 32 different sampling stations located along the estuary, allows
three groups of elements and compounds with a distinct origin to be determinated. So, Cu and Zn have a clear fluvial provenance,
whereas PO4 and As are clearly industrial wastes and Cl, K, Ca, Li, Rb and Sr come from the sea. From the factorial analyses we can deduce
the existence of two agents controlling the behavior of the analyzed elements, which are: the tidal exchange with the open
sea and the fluvial supply.
Received: 20 November 1998 · Accepted: 11 August 1999 相似文献
13.
M. Holá J. Kalvoda O. Bábek R. Brzobohatý I. Holoubek V. Kanický R. Skoda 《Environmental Geology》2009,58(1):141-151
Heavy metal concentrations were studied in the scales of recent and subrecent (2–25 years old) fish buried in the oxbow lake
sediments of the Morava River. The samples were taken from two cores up to 4-m deep and analysed using laser ablation inductively
coupled plasma mass spectrometry (LA-ICP-MS) and an electron microprobe analysis (EMPA). The results were compared with heavy
metal concentrations of bulk samples of the embedding sediment. The study has revealed substantial differences in heavy metal
contents existing between the recent and subrecent fish scales documenting an extreme rapidity of the diagenesis/fossilization
processes. The most apparent features of the early fossilization include the quick loss of the mucous envelope, collagen and
magnesium and an enormous increase in the heavy metal concentrations in particular iron, which is connected with a colour
change. The variations in heavy metal contents in fish scales within a sample are attributed to variations in heavy metal
content in the environment and variable amounts of organic matter in the embedding sediment. In contrast to the contamination
of the embedding sediment, no general increase in heavy metal concentrations in fish scales was observed down to the cores.
It is inferred that the rapid sorption stabilizes the biologic hydroxyapatite of the fish scales, which thus rapidly attain
a thermodynamic equilibrium with the embedding water-saturated sediment. The results show that the processes of sorption,
fossilization and stabilization of hydroxyapatite can act very quickly over a time scale of several years and represent thus
a great advantage in the preservation of the original signals of the ancient environments. 相似文献
14.
Heavy metal distribution and environmental status of Doon Valley soils, Outer Himalaya, India 总被引:1,自引:0,他引:1
K. K. Purohit P. K. Mukherjee P. P. Khanna N. K. Saini M. S. Rathi 《Environmental Geology》2001,40(6):716-724
Doon Valley is surrounded by two major river systems (Ganga and Yamuna) on either side, with a water divide passing nearly
across the centre of the valley, and is sandwiched between two mountain ranges in the fragile ecological systems of the Himalayan
foothills. In total 398 soil samples were collected from the valley in a grid pattern (∼1 sample per 2 km2) and investigated for their heavy metal (Cr, Cu, Ni, Pb and Zn) abundances that are environmentally sensitive. Comparison
of the heavy metal abundances with the contamination threshold values (CTV) revealed that most of these elemental abundances
in Doon Valley soils fall well within the range of the uncontaminated to slightly contaminated category. In the case of Cr
and Ni, a sizeable number of samples exceeded the CTV (250 and 100 mg kg–1 respectively) with an overall background value of 109 and 52 mg kg–1 respectively. Sites of high Cr and Ni mostly occur in the Ganga Catchment (GC) sector that includes even relatively undisturbed
forestland. The source of this contamination is attributed to geological factors which indicate contribution from the mafic
volcanics of the Lesser Himalaya. This is also consistent with the distribution pattern of Mn and Fe, though their abundance
levels are not alarming. The background concentration of Pb is low (22 mg kg–1) in Doon Valley soils; however, signs of gradual Pb contamination are palpable in and around the centre of the Dehra Dun
city and along the highways. Aluminium normalized heavy metal ratios were found to exhibit narrow variability in the case
of Cu, Ni and Cr and had good correlation with Al, indicating their affinity and association with the clay minerals. On the
other hand, Pb and Zn seem to be associated with non-silicate sources.
Received: 7 January 2000 · Accepted: 30 July 2000 相似文献
15.
Assessment of heavy metal accumulation in macrophyte, agricultural soil, and crop plants adjacent to discharge zone of sponge iron factory 总被引:1,自引:0,他引:1
The present study deals with the characterization of effluent released from sponge iron industries and distribution of heavy
metals in soil and macrophytes near to effluent discharge channel. Apart from this, accumulation of heavy metals in nearby
soil and vegetation system irrigated with effluent-contaminated water is also the subject of this study. Physico-chemical
analysis of effluent reveals that the concentration of total suspended solids (TSS), total hardness (TH), iron (Fe2+), and oil and grease are greater than the IS (1981) norms for discharge of water into inland water body. The soil along the sides of the effluent channel also shows higher
concentration of heavy metals than the background soil. The enrichment of the heavy metals are in the order of Chromium (Cr) > Iron
(Fe) > Manganese (Mn) > Zinc (Zn) > Copper (Cu) > Cadmium (Cd). Macrophytes growing along the sides of the effluent channel
also show significant accumulation of heavy metals almost in the same order as accumulated in soil. Higher uptake of heavy
metals by these varieties reveals that these species can be used for future phytoremediation. The effluent as well as contaminated
water is extensively used for irrigation for growing vegetables like tomato (Lycopersicon esculatum) in the surrounding areas. Heavy metal accumulation in this agricultural soil are in the sequence of Cr > Fe > Mn > Zn > Cu > Cd.
More or less similar type of accumulation pattern are also found in tomato plants except Fe and Zn exceeding Cr and Mn. Transfer
Factor of heavy metals from soil to tomato plants (TFS) shows average value of <1, suggesting less uptake of heavy metals from soil. Among the plant parts studied, fruit shows
least accumulation. Although tomato plants show some phenotypic changes, the survival of tomato plants as well as least accumulation
of metals in fruit reveals their tolerance to heavy metals. Therefore it may be suggested that this plant can be grown successfully
in the heavy metal contaminated soil. Further research work on in situ toxicity test will be necessary in order to identify
the most resistive variety on this particular type of contaminated site. 相似文献
16.
In an attempt to delineate heavy metal contamination precincts and to evaluate the extent and degree of toxic levels, besides
their possible sources, 38 water samples from Ankaleshwar Industrial Estate, south Gujarat, India were analyzed. By clutching
geochemical analyses and GIS-based colour composites areas depicting anomalously high concentration of heavy metals (Mo, Zn,
Pb, Ni, Co, Cd, etc.) in the groundwater were revealed. The multicomponent overlays in grey-scale facilitated in identifying
situates of heavy metal ‘hot spots’, and lateral protuberances of the contamination plume around defile stretch of the main
stream Amla Khadi flowing through the area. The multiple pollution plumes emerging from other parts of the area further coincide
with effluent laden streams and small channels indicating industrial establishments as major sources of groundwater contamination.
Influent nature of the streams, accelerated infiltration process, high mass influx and shallow groundwater table are the factors
conducive for easy access of heavy metals to the phreatic aquifers affecting over 20 km2 area. On the basis of P/U ratios (concentration of metals in polluted water to unpolluted water), geogenic and anthropogenic sources have been identified.
Very high levels of technogenic elements present in the ground water raise concerns about possible migration into food crops,
as the area is an important horticultural locale and is highly cultivated. 相似文献
17.
Charles W. Martin 《Environmental Geology》2009,58(4):803-814
Between 1995 and 2007, the concentrations of Pb and Zn in floodplain soils increased along a 60-km reach of the Lahn River,
Germany, suggesting that the storage of some metals in the fluvial system is out of phase with recent declines in the release
of metals to the environment. Re-sampling of surface soils to 5 cm along five transects perpendicular to the river indicated
that the concentration of Pb increased between 1995 and 2007 along two transects and was statistically unchanged at the other
three. The concentration of Zn increased at three of five transects and was statistically unchanged at two transects over
the same time period. Between 1995 and 2007, concentrations of Cu were statistically equal along four of five transects and
declined at the other transect. The increase in Pb and Zn was greater in a more rural than in a more urbanized reach of the
Lahn River. Soil texture and organic matter content had virtually no impact on the concentration of metals. The increase in
Pb concentration suggests a lag between the decline in Pb releases to the environment and its movement through the fluvial
system. Increased Zn storage may result from the high solubility of the metal and the relative ease with which it moves through
the environment. Environmental controls appear to have slowed Cu storage along the Lahn River, but are not yet reflected in
Pb and Zn storage. 相似文献
18.
Assessment of heavy metal pollution in urban topsoils from the metropolitan area of Mexico City 总被引:2,自引:0,他引:2
O. Morton-Bermea E. Hernández-Álvarez G. González-Hernández F. Romero R. Lozano L.E. Beramendi-Orosco 《Journal of Geochemical Exploration》2009
This study reports the degree of heavy metal pollution (Cr, Cu, Ni, Pb, Zn and V) in 135 urban topsoil samples from the metropolitan area of Mexico City. Pollution indices (PI) were calculated to identify the metal accumulation with respect to the background values. The levels of heavy metals in the analyzed samples show a wide range of variation. Lead, Zn and Cu are the elements most enriched in the analyzed area, presenting pollution indexes of up to 23.8, 21.6 and 12.4, respectively. Geochemical maps were produced to assess the spatial distribution of pollution index. It is concluded that emissions from vehicles may be the major source of Pb urban contamination; furthermore, other small or large factories are possible sources for soil pollution (Cu, Zn). The concentration of Cr, Ni, and V in most of the analyzed samples do not appear to reach pollution levels. The assessment of the soil environmental quality in the metropolitan area Mexico City in terms of PI can be used as the basis for a regular monitoring program for implementing suitable pollution control measures. 相似文献
19.
20.
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