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1.
《Chemical Geology》2002,182(2-4):377-394
Bulk heavy metal (Fe, Mn, Zn, Cu, Pb, Cd), Al, organic carbon and carbonate concentrations, grain sizes, and δC13 of the organic carbon distributions were studied in sediments collected throughout the East China Sea continental shelf and the Yangtze River Delta. The results demonstrated that terrigenous sediments from the Yangtze River is a dominating factor controlling the spatial variations of heavy metals and organic carbon concentrations on the East China Sea continental shelf. In addition, grain size and recent anthropogenic influences are also major factors modifying the spatial and vertical variations of heavy metals.Large spatial variations with a band type distribution of heavy metals, grain size, organic carbon and carbonate were observed. Higher concentrations of heavy metal and light δC13 of the organic carbon were found primarily in the Deltaic and inner shelf sediments. The band type distribution generally followed the coastline with little variations in the north–south direction. Away from the Delta and inner shelf (west–east direction), most heavy metal concentrations decreased rapidly with the exception of Cd where high concentrations of Cd were also found in the carbonate-rich shelf break sediments. Coarse-grained relict sediments and biogenic carbonate are two primary diluting agents for the fine-grained aluminosilicate sediments from the Yangtze River with high concentrations of heavy metals.Unusually high concentrations of Cu, Pb, and Cd showed both spatially and vertically that more pollution prevention measures are needed in the Yangtze River drainage basin in order to prevent further heavy metal pollution of the East China Sea inner continental shelf. 相似文献
2.
Distribution of heavy metals in the clastic fine-grained sediments of Gavkhuni playa lake (Southeast of Isfahan,Iran) 总被引：1，自引：1，他引：0
The sedimentary basin of Gavkhuni playa lake includes two sedimentary environments of delta and playa lake. These environments consist of mud, sand and salt flats. There are potentials for concentration of heavy metals in the fine-grained sediments (silt and clay) of the playa due to existence of Pb/Zn ore deposits, industrial and agricultural regions in the water catchment of Zayandehrud River terminating to this area. In order to study the concentration of heavy metals and the controlling factors on their distribution in the fine-grained sediments, 13 samples were taken from the muddy facies and concentration of the heavy metals were determined. The results showed that the heavy metal concentrations range in the sediments (in ppm) are Mn (395.5–1,040), Sr (100.4–725.76), Pb (14.66–91.06), Zn (23.59–80.9), Ni (37–73.66), Cu (13.83–29.83), Co (5.73–13.78), Ag (3.03–4.76) and Cd (2.3–5.5) in their order of abundances. The concentration of Ag is noticeable in the sediments relative to the average concentration of this element in mud sediments. The amounts of Pb and Zn are relatively high in all the samples in comparison with the other elements. The concentration of Ni is relatively high in the oxidized samples. The distribution of Pb is directly related to organic matter content of the sediments. The concentrations of Zn, Sr, Cu, Co and Cd in the samples of the playa are lower than those in the delta. The amount of illite is another factor influencing Zn and Pb concentrations. Sr is more concentrated in the sediments with the high content of calcium carbonate. The distribution pattern of Cu, Co, Pb and Mn resembles to that of the clay content of the sediments. The clay content shows positive correlations with Co, Cu and Mn concentrations and negative correlation with Ag. The Sr and Ag concentrations are positively correlated with the amount of CaCO3. The amounts of Co, Cu, Ni and Mn show negative correlations with the calcium carbonate content. Pb and Co are noticeably correlated with Mn. 相似文献
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Geochemical and statistical approach for evaluation of heavy metal pollution in core sediments in southeast coast of India 总被引：6，自引：2，他引：4
B. R. R. Seshan M.Phil. U. Natesan Ph.D. K. Deepthi M.Sc. 《International Journal of Environmental Science and Technology》2010,7(2):291-306
Industrialization coupled with urbanizaton has led to stress in the Buckingham Canal which runs parallel to Bay of Bengal at a distance of around 1 km from the coastline. 4 sediment cores were collected along Ennore — Pulicat stretch to determine acid leachable trace metal concentration. Core samples were collected using gravity corer. The cores were sliced horizontally at 2.5 cm to determine the grain size, sediment composition, pH, organic matter, calcium carbonate, acid leachable trace metals; cadmium, chromium, copper, lead, zinc. The trace metals were extracted using acid mixture containing hydro fluoric acid, nitric acid and sulphuric acid and analysed by atomic emission spectrophotometer. In an attempt to infer anthropogenic input from geogenic input, several approaches including comparison with sediment quality guidelines — ecotoxicological sense of heavy metal contamination and classification by quantitative indexes such as geoaccumalation index, anthropogenic factor, enrichment factor, contamination factor and degree and pollution load index was attempted. Grain size analysis and sediment composition of core samples shows Ennore is sandy in nature having a neutral pH. Organic matter enrichment is observed to a higher extent in core 3. Core 2 at a depth of 5 cm shows organic matter of 9.4 %. calcium carbonate is totally absent at the surface sediments in core 2. Cores collected within the canal showed a higher heavy metal concentration than the cores collected from Pulicat lagoon and 2 km into the Ennore Sea. The trace metal concentration for cadmium, lead and zinc in Ennore does not pose a threat to the sediment dwelling fauna whereas chromium and copper are likely to pose a threat. Quantitative indexes place Ennore under moderately polluted. Ennore is likely to face a serious threat of metal pollution with the present deposition rates unless stringent pollution control norms are adopted. 相似文献
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6.
小秦岭金矿区土壤重金属生物有效性与影响因素 总被引：1，自引：0，他引：1
土壤中重金属生物有效性与影响因素分析是土壤重金属风险管控的关键问题。通过实地调查、现场采样、实验测试、综合分析等方法,分析了研究区100km2内Hg、Pb、Cd、Cr、As、Cu、Zn七种重金属元素的有效态含量特征,研究了这些重金属有效态含量之间、有效态含量与全量、有效态与土壤pH、有机质含量、粒度等基本理化参数之间的相关性,分析了重金属污染来源。结果表明,土壤中Hg、Pb、Cd、Cr、As、Cu、Zn七种重金属有效态的平均含量分别为2.29mg/kg、594mg/kg、2.52mg/kg、6.30mg/kg、2.16mg/kg、48.14mg/kg、50.21mg/kg,其变异系数大小为:HgPbCuZnCdAsCr。Hg的变异系数最大,是由于金矿选矿活动采用混汞法提金排放的尾矿堆(库)分布不均。Hg、Pb、Cd、Cu、Zn有效态量与全量之间均存在显著的相关性;土壤有机质与重金属有效态之间存在显著的相关性;土壤pH与有效态重金属之间存在显著的负相关性;土壤粒度对重金属有效态的累积影响不明显。 相似文献
7.
《Applied Geochemistry》2001,16(9-10):1139-1151
Establishing ‘reference sites’ is a difficult task and a critical factor in determining the baseline functioning of ecosystems. The information thus obtained on nutrient and contaminant background concentrations in turn subsidizes the remediation of impacted landscapes. This paper reports a study on metal (Cr, Cu, Pb, Zn, Mn, Fe and Al) and nutrient (C) distribution in sediments from Capivari River watershed (Praia do Sul Biological Reserve, Ilha Grande, Rio de Janeiro State, Brazil), an area where typical SE Brazilian coastal ecosystems are located. Contrary to what one would expect from the high rate at which these ecosystems have been deteriorating in recent decades, the study site is surprisingly well preserved. The present study was developed to assess variations in heavy metal concentrations in river basin sediments, to identify the geochemical carriers of these elements, and determine the influence of water quality and organic matter on their distribution. Results showed that heavy metal distribution has been influenced by the natural biogeochemical properties of those ecosystems found in an upland-to-lowland sequence in the watershed. Minimum and maximum total concentration were: 5 and 23 mg/kg for Cr; 4 and 29 mg/kg for Cu; 13 and 53 mg/kg for Pb; 24 and 142 mg/kg for Zn; 54 and 342 mg/kg for Mn; 0.8 and 7.2% for Fe; 0.5 and 4.9% for Al; 6.3 and 25% for C. The pH and EH are the key-parameters in explaining total metal concentration decrease in the swamp area, where dissolution processes and losses through metal transport seem important. The most important geochemical carriers are Al in the basin’s “continental” stretch and Fe in the estuarine portion. The data also provide evidence showing that organic matter is the key-parameter in Cu concentration control in the sediments through burial and accumulation processes especially in the swamp area. Heavy metal concentrations in sediments from the study area are generally lower than those found in similar regional ecosystems. Surface enrichment in heavy metal concentrations in collected sediment cores was not observed. The authors therefore conclude that this site is suitable as a ‘reference site’ for studies on the biogeochemistry and ecotoxicology of SE Brazilian coastal ecosystems. 相似文献
8.
Partitioning of heavy metals in surface Black Sea sediments 总被引：1，自引：0，他引：1
Bulk heavy metal (Fe, Mn, Co, Cr, Ni, Cu, Zn and Pb) distributions and their chemical partitioning, together with TOC and carbonate data, were studied in oxic to anoxic surface sediments (0–2 cm) obtained at 18 stations throughout the Black Sea. TOC and carbonate contents, and available hydrographic data, indicate biogenic organic matter produced in shallower waters is transported and buried in the deeper waters of the Black Sea. Bulk metal concentrations measured in the sediments can be related to their geochemical cycles and the geology of the surrounding Black Sea region. Somewhat high Cr and Ni contents in the sediments are interpreted to reflect, in part, the weathering of basic-ultrabasic rocks on the Turkish mainland. Maximum carbonate-free levels of Mn (4347 ppm), Ni (355 ppm) and Co (64 ppm) obtained for sediment from the shallow-water station (102 m) probably result from redox cycling at the socalled ‘Mn pump zone’ where scavenging-precipitation processes of Mn prevail. Chemical partitioning of the heavy metals revealed that Cu, Cr and Fe seem to be significantly bound to the detrital phases whereas carbonate phases tend to hold considerable amounts of Mn and Pb. The sequential extraction procedures used in this study also show that the metals Fe, Co, Ni, Cu, Zn and Pb associated with the ‘oxidizable phases’ are in far greater concentrations than the occurrences of these metals with detrital and carbonate phases. These results are in good agreement with the recent studies on suspended matter and thermodynamic calculations which have revealed that organic compounds and sulfides are the major metal carriers in the anoxic Black Sea basin, whereas Fe-Mn oxyhydroxides can also be important phases of other metals, especially at oxic sites. This study shows that, if used with a suitable combination of the various sequential extraction techniques, metal partitioning can provide important information on the varying geological sources and modes of occurrence and distribution of heavy metals in sediments, as well as, on the physical and chemical conditions prevailing in an anoxic marine environment. 相似文献
9.
Hong-Jiao Pang Shuang-Shuang Lyu Xue-Gang Chen Ai-Min Jin Pei-Sun Loh Fei Li Yan Jiang Xian-Hui Yang Kang-Kang Yan Zhang-Hua Lou 《Environmental Earth Sciences》2017,76(17):627
In order to study the heavy metal accumulation and distribution in the roots, stems, and leaves of Spartina alterniflora, we collected S. alterniflora samples and the associated sediments along three transects at the Andong tidal flat, Hangzhou Bay. Co, Ni, Cd, Pb, Cu, and Zn were mainly accumulated in the aerial parts (stems and leaves) of the plants, and their distributions depended on their mobility and their roles during the metabolism processes of S. alterniflora. The concentrations of Cu, Zn, Cd, Hg, and Pb were significantly enhanced with the increasing of heavy metal concentrations in the sediments, while those of Co and Ni remained relatively constant. Bioaccumulation factors results showed that the serious heavy metal contamination in the sediments from the transect A may overwhelm the accumulation capability of the plants. In addition, the physicochemical properties of the sediments and the pore water therein also play a role in the heavy metal concentrations and accumulations in the plants, because they can influence the behaviors and bioavailabilities of heavy metals during nutrition and bioaccumulation processes of the plants. The sediments with vegetation did not show significantly decreased heavy metal concentration with respect to the unvegetated sediments, although the plants did absorb heavy metals from the sediments. Principal component analysis and correlation analyses indicated that Co–Ni, Cu–Cd–Hg behaved coherently during accumulation, which may be ascribed to their similar accumulation mechanisms. This work provided essential information on the heavy metal accumulation by plants in a tidal flat, which will be useful for the environmental control through phytoremediation at estuaries. 相似文献
10.
福建龙海土壤重金属含量特征及影响因素研究 总被引：1，自引：0，他引：1
为有效预防土壤重金属生态风险,以福建龙海市表层土壤为研究对象,应用经典统计分析、随机森林等方法,研究重金属元素含量特征及其影响因素。结果表明：(1)第四纪冲洪(海)积成因水稻土中多数重金属元素含量较高;(2)燕山期中酸性岩风化形成的残坡积红壤中重金属元素活动态含量较高;(3)As、Cu、Ni形态含量与全量相关性较好,而Cd、Cr、Hg的多数形态含量与全量相关性较差;(4)除元素全量外,土壤有机质对弱有机结合态重金属(不包括Ni、Pb元素)以及离子交换态、碳酸盐结合态Cd、Zn有重要影响,阳离子交换量对各形态Ni,(Fe×Al)/Si对各形态Cu具有重要影响,而土壤成因、土壤类型对重金属形态组成的影响较小。研究表明土壤重金属形态组成及其富集区与其全量不尽一致,土壤重金属生态风险评价应考虑土壤重金属形态分布特征。 相似文献
11.
A field study was conducted to clarify the effect of rhizosphere processes on the accumulation and partitioning of heavy metals
(Pb, Zn, Cu, Cr, Cd and Ni) in mangrove sediments. Metals were fractionated by a sequential extraction procedure into three
chemically distinct fractions: water soluble, exchangeable and carbonate bound (B1), Fe–Mn oxide bound (B2), and organic and
sulfide bound (B3). Results indicate that rhizosphere processes tend to increase the metal concentrations in the rhizosphere
sediments. However, plant uptake may result in the decrease of the metal concentrations in the rhizosphere sediments when
the metal concentrations are relatively low in the bulk sediments. Compared with the bulk sediments, the rhizosphere sediments
have low concentrations of heavy metals in the B1 and B2 fractions and high concentrations in the B3 fraction. Either an increase
or decrease in the residual fraction of heavy metals in the rhizosphere sediments may appear, depending on whether the formation
of the refractory metal-organic compounds or the activation of the residual fractions dominates. Results also indicate that
mangrove plants absorb and store non-essential metals in the perennial tissues, thus reducing the export of non-essential
metals via leaf litter transport. Mangrove plants are excellent candidates for phytostabilization of heavy metals in intertidal
substrates. 相似文献
12.
为了研究内蒙古赤峰市巴林左旗白音诺尔铅锌矿区采矿对哈力黑河生态环境造成的影响,从上游向下游采集了6个河流沉积物样品,测定其pH、LOI、粒度以及As、Cu、Pb、Zn、Cd等5种重金属的总量和赋存形态,并对测试结果进行分析。研究结果表明:（1）1#尾矿库是造成沉积物中Pb、Zn和Cd等重金属显著升高的主要原因。（2）沉积物重金属与粗粉砂（16~63 μm）的相关系数为0.79~0.95,表明重金属易富集于粗粉砂上,而沉积物的pH和有机质对重金属总量的变化影响不显著。（3）沉积物中As和Pb以残渣态和铁锰结合态为主,分别占总量的78.82%~89.87%和36.96%~78.20%。Cu和Zn以残渣态、强有机结合态和铁锰结合态为主,分别占总量的76.38%~85.96%和74.94%~90.34%。Cd则以离子交换态、碳酸盐结合态和强有机结合态为主,占总量的51.15%~79.53%,而离子交换态Cd占了总量的5.72%~49.63%。因此,Cd对河流生态环境的潜在威胁最大。（4）离子交换态Cd与沉积物pH相关系数为-0.813,两者呈极强负相关性。当沉积物pH由弱酸性转化为弱碱性时,离子交换态Cd含量从33.44%降低至5.72%,显著减小。 相似文献
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Spatio-temporal dynamics of heavy metals in sediments of the river estuarine system: Mahanadi basin (India) 总被引：1，自引：1，他引：0
Sanjay Kumar Sundaray Binod Bihari Nayak Byeong-Gweon Lee Dinabandhu Bhatta 《Environmental Earth Sciences》2014,71(4):1893-1909
Dynamics of heavy metals in the surface sediments of Mahanadi river estuarine system were studied for three different seasons. This study demonstrates that the relative abundance of these metals follows in the order of Fe > Mn > Zn > Pb > Cr > Ni ≥ Co > Cu > Cd. The spatial pattern of heavy metals supported by enrichment ratio data, suggests their anthropogenic sources possibly from various industrial wastes and municipal wastes as well as agricultural runoff. The metal concentrations in estuarine sediments are relatively higher than in the river due to adsorption/accumulation of metals on sediments during saline mixing, while there is a decreasing trend of heavy metal concentrations towards the marine side. The temporal variations for metals, such as Fe, Mn, Zn, Ni and Pb exhibit higher values during monsoon season, which are related to agricultural runoff. Higher elemental concentrations are observed during pre-monsoon season for these above metals (except Ni) at the polluted stations and for metals, such as Cr, Co and Cd at all sites, which demonstrate the intensity of anthropogenic contribution. R-mode factor analysis reveals that “Fe–Mn oxy hydroxide”, “organic matter”, “CaCO3”, and “textural variables” factors are the major controlling geochemical factors for the enrichment of heavy metals in river estuarine sediment and their seasonal variations, though their intensities were different for different seasons. The relationships among the stations are highlighted by cluster analysis, represented in dendrograms to categorize different contributing sites for the enrichment of heavy metals in the river estuarine system. 相似文献
14.
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
15.
Mercury distribution was examined in the sediments of Lake Baikal that were sampled within the scope of the Baikal Drilling International Project in 1996–1999. The Hg concentrations in the ancient sediments are close to those in the modern sediments with the exception of a few peak values, whose ages coincide with those of active volcanism in adjacent areas. Mercury was demonstrated to be contained in the sediments in the adsorbed Hg0 mode, predominantly in relation with organic matter. When the organic matter of the bottom sediments is decomposed in the course of lithification, Hg is retained in the sediments adsorbed on the residual organic matter, and the concentration of this element corresponds to its initial content in the bottom sediments during their accumulation. Mercury concentrations in lithologically distinct bottom sediments of Lake Baikal and its sediments as a whole depend on the climate. Sediments that were formed during warm periods of time contain more Hg than those produced during cold periods or glaciation. Periodical variations in the Hg concentrations in the bottom sediments of Lake Baikal reflect the variations in the contents of this element in the Earth’s atmosphere in the Late Cenozoic, which were, in turn, controlled by the climatic variations on the planet and, thus, can be used for detailed reconstructions of variations in the average global temperature near the planet’s surface. 相似文献
16.
深水碳酸盐沉积研究进展 总被引：5，自引：0，他引：5
深水碳酸盐沉积包括深水重力流作用形成的异地沉积和非重力流沉积，在非重力流沉积中又有深水牵引流(等深流、内波、内潮汐等)沉积和静态原地碳酸盐沉积。深水碳酸盐沉积与重力流及等深流活动有关，也受控于表层水碳酸盐产率、陆源物质的稀释作用及深水对碳酸盐的溶解作用。大量研究表明，深水碳酸盐沉积对海平面升降与气候变化响应明显，无论是重力流或非重力流沉积均有体现，通过深水碳酸盐沉积研究可以提取地质历史时期环境变化的信息，同时，某些深水碳酸盐沉积岩中蕴藏着丰富的石油、天然气和其他沉积矿产。由此开展此项研究具有重要的理论和实际意义。 相似文献
17.
A thermodynamic model of the behavior of heavy metals in bottom sediments during their eutrophication is developed. The results
show that liberation of heavy metals from the reduced ferrous sorbent is accompanied by sorption on clay and organic sorbents.
The process is complicated by competitive correlations between heavy metals and calcium ions, while the formation of carbonate
cement in the sediments yields additional sorption. As a result, the predicted concentrations of the majority of microelements,
namely heavy metals, in the interstitial water of the reduced bottom sediments do not exceed the maximum permissible concentration
(MPC). 相似文献
18.
根系土中重金属元素分布特征及在农作物中的迁移 总被引：1，自引：0，他引：1
以上海市金山区为对象,分析了农用地土壤重金属元素的形态分布特征,以及元素的有效态（水溶态、离子交换态）与全量、有机质、pH等的相关性;根据重金属元素在稻米、蔬菜等不同农作物中的含量,分析了其迁移及生物有效性。结果表明：不同元素的形态组成差异较大;Pb、Zn、Ni元素的有效态与环境因素（pH、有机质）关系密切;土壤中重金属元素Cd最为活跃且易发生迁移,在多种农作物中有较为明显的富集;稻米中重金属元素的富集程度相对较小。研究成果可为土壤污染治理、种植结构调整、土地合理利用提供有益借鉴。 相似文献
19.
太湖MS岩芯重金属元素地球化学形态研究 总被引：21，自引：4，他引：17
采用BCR三步提取法对太湖MS岩芯沉积物中Cu、Fe、Mn、Ni、Pb和Zn等6种重金属元素的化学形态进行了研究.结果表明,有效结合态的Cu、Ni和Pb主要以有机物及硫化物结合态、Fe-Mn氧化物结合态存在,Fe和Zn主要以Fe-Mn氧化物结合态存在,Mn主要以可交换态及碳酸盐结合态存在;Fe-Mn氧化物结合态的Ni、Pb和Zn与可还原态的Mn有较好的正相关关系,有机物及硫化物结合态的Cu、Mn、Ni、Pb和Zn与有机碳含量有较好的正相关关系;重金属形态分布体现了重金属元素地球化学性质的差异,以及重金属形态含量与沉积物理化性质的关系.沉积岩芯重金属元素形态垂向变化规律及次生相富集系数表明,Cu、Mn、Ni、Pb和Zn在沉积岩芯13～4 cm有效结合态含量较稳定,为自然沉积;4～0 cm有效结合态含量明显升高,存在一定程度的人为污染.根据137Cs测年结果判断,沉积岩芯Cu、Mn、Ni、Pb和Zn等重金属污染开始于20世纪70年代末期,主要污染元素及污染历史与太湖流域污染工业类型及经济发展阶段相吻合. 相似文献
20.
恬矿库周围土壤中重金属存在形态特征研究 总被引：48，自引：4，他引：44
通过对大冶铜绿山铜铁矿尾矿库周围土壤中重金属形态分析实验,研究了重金属各种形态在土壤中的分布特征。由对比实验可知,尾矿库周围土壤中Ｃｕ、Ｐｂ、Ｚｎ、Ｃｄ等重金属含量都显著地高于对照样品,书经受到重金属的严重污染。土壤中重金属形态分布征为：ｗ（Ｃｒ、Ｚｎ、Ｆｅ）;可变换态〈碳酸盐态〈有机态〈铁锰氧化态〈残渣态;ｗ（Ｃｕ、Ｐｂ）：可变换态〈碳酸盐态〈有机态〈残渣态〈铁锰氧化态;ｗ（Ｃｄ）：残渣态,有机 相似文献