首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 656 毫秒
1.
The paper presents data on the specifics of the distributions of chemical elements in natural waters of the Kola North depending on the landscape–geochemical characteristics of the water catchment areas and aerotechnogenic pollution. The territory is subdivided into seven zones with different dominant rock types and typical landscapes. Lakes in the Kola region generally contain elevated concentrations of Cu, Ni, Co, Cr, V, Mo, U, Sb, Bi, Al, Fe, Mn, Sr, Li, Rb, Pb, Zn, Cd, La, and Ce. The waters of lakes in the influence zones of Cu–Ni mines are enriched in La, Ce, Sm, Gd, Pr, and Nd. In waterlogged landscapes, waters are enriched in certain trace elements because of their migration with humic acids. Technogenic acidic precipitation is proved to result in leaching of several elements, first of all Cd, Zn, and As (as well as other elements contained in rocks composing the water catchment areas) and their transfer into the waters.  相似文献   

2.
The acid mine drainage (AMD) discharged from the Hejiacun uranium mine in central Hunan (China) was sampled and analyzed using ICP-MS techniques. The analyzing results show that the AMD is characterized by the major ions FeTotal, Mn, Al and Si, and is concentrated with heavy metals and metalloids including Cd, Co, Ni, Zn, U, Cu, Pb, Tl, V, Cr, Se, As and Sb. During the AMD flowing downstream, the dissolved heavy metals were removed from the AMD waters through adsorption onto and co-precipitation with metal-oxhydroxides coated on the streambed. Among these metals, Cd, Co, Ni, Zn, U, Cu, Pb and Tl are negatively correlated to pH values, and positively correlated to major ions Fe, Al, Si, Mn, Mg, Ca and K. The metals/metalloids V, Cr, Se, As and Sb are conservative in the AMD solution, and negatively-correlated to major ions Na, Ca and Mg. Due to the above different behaviors of these chemical elements, the pH-negatively related metals (PM) and the conservative metals (CM) are identified; the PM metals include Cd, Co, Ni, Zn, U, Cu, Pb and Tl, and the CM metals V, Cr, Se, As and Sb. Based on understanding the geochemistry of PM and CM metals in the AMD waters, a new equation: EXT = (Acidity + PM)/pH + CM × pH, is proposed to estimate and evaluate extent of heavy-metal pollution (EXT) of AMD. The evaluation results show that the AMD and surface waters of the mine area have high EXT values, and they could be the potential source of heavy-metal contamination of the surrounding environment. Therefore, it is suggested that both the AMD and surface waters should be treated before they are drained out of the mine district, for which the traditional dilution and neutralization methods can be applied to remove the PM metals from the AMD waters, and new techniques through reducing the pH value of the downstream AMD waters should be developed for removal of the CM metals.  相似文献   

3.
Variations in As, Ba, Bi, Cd, Co, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Se, Sn, Th, Tl, U, W, and Zn uptake were evaluated in young, middle-aged, and mature basil, tomato, zucchini, and sunflower plants grown in soils amended with 5, 10, and 20% by weight fly ash. Elements susceptible to uptake with increasing fly ash were As and Tl, with As exceeding potentially toxic levels in basil and zucchini. Temporal variations in element uptake included (1) increasing Ba and Cd concentrations in tomato and As, Ba, Cd, and Tl in zucchini, (2) decreasing Co concentrations in tomato, zucchini, and sunflower, Ni in zucchini, and Tl in basil, and (3) increasing As and Ni concentrations in basil and Pb in zucchini and sunflower during early growth followed by decreasing concentrations at maturity. Although most of the trace elements were below reported toxic levels, the elevated concentrations of As in plant tissue suggests that fly ash treatment programs can lead to potentially toxic accumulations of As, and thus, should be carefully monitored.  相似文献   

4.
西藏柯月Pb-Zn-Sb-Ag多金属矿床位于雅鲁藏布江缝合带(IYS)与藏南拆离系(STDS)之间的北喜马拉雅成矿带。该矿床经详查验证,4 300 m以浅的矿体赋存于日当组钙质板岩夹薄层泥晶灰岩中,严格受北东向断裂控制,但深部延伸不明。本文通过该矿床I号矿体原生晕地球化学特征分析,对此问题进行初步探讨。研究表明,前缘晕元素为Hg、As、Tl,近矿晕元素为Pb、Zn、Sb、Ag、Au、Cd、Cu、Mn,尾晕元素为Sn、In、Bi;采用改良的格里戈良分带指数法计算分带序列为In-Mn-As-Cu-Zn-Cd-Bi-Pb-Sn-Hg-Tl-Ag-Au-Sb,重心法计算分带序列为In-Mn-As-Cu-Cd-Zn-Hg-Bi-Sn-Pb-Ag-Sb-Tl-Au;同时,讨论原生晕地球化学参数变化规律,并以各元素的几何平均值累乘比建立矿体的剥蚀参数模型及矿体原生晕叠加理想模型。综合以上分析,推测矿床有多次成矿作用叠加,上部存在剥蚀至尾部的矿体,而深部可能有矿体延伸。  相似文献   

5.
We investigate the degassing of volatile heavy metals from natural basalt and dacite and synthetic rhyolite melts doped with Bi, Pb, Tl, Au, Re, Sb, Sn, Cd, Mo, As, Cu in Pt capsules over a range of temperatures (1200-1430 °C) exposed to air at 0.1 MPa. We also investigated the effects of ligands on degassing by adding known concentrations of Cl and S. During the experiments concentration gradients normal to the melt/gas interface arose for the trace metals Au, Tl, As, Cd, Re, Bi and Pb, as shown by measurements by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) on the quenched glasses. In contrast, erratic concentration gradients occurred for Cu, Mo, Sn, Sb due to the development of compositional cords in the glass for those elements. The diffusivities for Au, Tl, As, Cd, Re, Bi and Pb (in decreasing order of volatility) followed an Arrhenius relationship with log D at 1260 °C varying from −12 to −17. The addition of Cl and S were shown to increase by two-to five-fold the volatilities of all metals, with S having a more profound effect. Diffusivities from the experiments were applied in a bubble growth model to examine the behavior of Tl and Pb in volcanic gases. The Tl/Pb ratio in gases shows much greater variation than can be explained by partitioning and magma composition alone, with diffusion serving to drastically enrich or deplete the Tl/Pb of gases to values significantly different from that of the melt.  相似文献   

6.
Increased offshore development in the Alaskan Arctic has stimulated interest in assessing potential impacts to the environment before the onset of any adverse effects. Concentrations of trace metals in sediments are used in this paper to provide one sensitive indicator of anthropogenic inputs from offshore activity over the past several decades. Sediments in coastal waters of the western Beaufort Sea are patchy with respect to sediment granulometry, organic carbon content, and concentrations of trace metals. However, results for surface sediments and age-dated cores show that nearly all samples contain natural concentrations of Ag, Ba, Be, Co, Cr, Cu, Hg, Ni, Pb, Sb, Tl, V and Zn, with metal/Al ratios that have been constant for many decades. Metal concentrations for incoming river-suspended matter compare well with sediment metal values and, along with vertical distributions in sediments, show no discernible diagenetic impacts that distort the sedimentary record for metals, except for Mn, As and possibly Cd. Slightly elevated concentrations of Ba, Hg, Ag, Sb and Zn were observed in a total of eight instances or in only 0.7% of the 1,222 data points for metals in surface sediments.  相似文献   

7.
Analysis of ten heavy metals (Ag, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sb, Zn) in six sediment cores from Wellington Harbour show both anthropogenic enrichments and diagenetic modifications. Absolute concentrations determined by two methods, x-ray fluorescence and acid leaching for bioavailability, are not comparable. However, vertical trends in concentrations of the cored sediment are comparable. To assess levels of anthropogenic pollution, enrichment factors (enriched concentrations in upper core divided by background levels in lower core) are preferred over index of accumulation (I geo) values because preindustrial or background levels of heavy metals are well constrained. The ten metals are placed into three groups: (1) Cu, Pb, and Zn, which show the most anthropogenic enrichment; (2) As, Cd, Cr, Ni, and Sb, which are often associated with anthropogenic pollution but show only minor enrichment; and (3) Fe and Mn, which are diagenetically enriched. Assuming harbor waters are well mixed, anthropogenic enrichments of Cu, Pb, and Zn, are time correlative, but the degree of enrichment depends on the method of analysis and core location. Levels of As, Cd, Pb, and Zn show small variations in preindustrial sediments that are not related to changes in grain size and probably result from changes in the oxidation-reduction potential of the sediments and salinity of the pore waters.  相似文献   

8.
The ash yield and concentrations of twenty-four minor and trace elements, including twelve potentially hazardous trace elements were determined in Mukah coal from Sarawak, Malaysia. Comparisons made to the Clarke values show that Mukah coal is depleted in Ag, Ba, Be, Cd, Co, Mn, Ni, Se, U, and V. On the other hand, it is enriched in As, Cr, Cu, Pb, Sb, Th, and Zn. Among the trace elements studied, V and Ba are associated predominantly with the clay minerals. Manganese, Cr, Cu, Th, and Ni are mostly bound within the aluminosilicate, sulphide and/or carbonate minerals in varying proportions, though a portion of these elements are also organically bound. Arsenic, Pb and Sb are mostly organically bound, though some of these elements are also associated with the sulphide minerals. Zinc is associated with both the organic and inorganic contents of the coal. Among the potentially hazardous trace elements, Be, Cd, Co, Mn, Ni, Se, and U may be of little or no health and environmental concerns, whereas As, Cr, Pb, Sb and Th require further examination for their potential health and environmental concerns. Of particular concern are the elements As, Pb and Sb, which are mostly organically bound and hence cannot be removed by physical cleaning technologies. They escape during coal combustion, either released as vapours to the atmosphere or are adsorbed onto the fine fly ash particles.  相似文献   

9.
Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis (INAA), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Cold-Vapor Atomic Absorption Spectrometry (CV-AAS) and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that: (a) the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; (b) the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; (c) the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; (d) the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that: (a) pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; (b) Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; (c) U, Zn, V, Na, P maybe controlled by phosphate or halite; (d) Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor.  相似文献   

10.
Zusammenfassung 119 Kohlengesteine, Torf, Ölschiefer und andere organogene Sedimente österreichischer Herkunft wurden emissionsspektrographisch im Kohlen- und Doppelbogen auf Ag, As, Be, Bi, Cd, Co, Cr, Cu, Ga, Ge, Hg, Mn, Ni, Pb, Sb, Sn, Ti, Tl, V und Zn untersucht.Die vorliegende Arbeit enthält die Analysentabellen. Eine abschließende Arbeit mit der Auswertung der Resultate wird angekündigt.  相似文献   

11.
Santiago, the capital of Chile, suffers from high air pollution levels, especially during winter. An extensive particulate matter (PM) monitoring and analysis program was conducted to quantify elemental concentrations of PM. Size-resolved PM samples (PM2.5 and PM10–2.5) from the La Paz and Las Condes stations in Santiago (2004–2005) were analyzed using ICP-MS. Most trace element concentrations (Cu, Pb, Zn, Mn, V, Sb, Pb and As) were higher during winter than during summer and were also higher at the La Paz station than at the Las Condes station. During the highest pollution events, As concentrations in PM2.5 (16 ng m?3) exceeded the annual average standard value (6 ng m?3). A 10-year time series showed decreasing Pb and As concentrations and slightly increasing Zn, Cu and Mn concentrations. Concentrations of Cr and Ni remained relatively constant. The implementation of new public policies in 1998 may explain the decreasing concentrations of Pb and As. Enrichment factor (EF) calculations identified two principal groups: elements with EF < 10 (Mg, Y, Zr, U Sr, Ca, Ti, and V) and EF > 10 (Rb, K, Cs, Fe, P, Ba, Mn, Ni, Cr, Co, Zn, Sn, Pb, Cu, Mo, Cd, As, Ag, and Sb), which were related to natural and anthropogenic PM sources, respectively. Three main PM sources were identified using factor analysis: a natural source (crustal matter and marine aerosol), combustion and copper smelting. Three other sources were identified using rare earth elements: fluid catalytic crackers, oil-fired power production and catalytic converters.  相似文献   

12.
涡阳花沟西10号煤中微量元素的有机亲和性   总被引:1,自引:0,他引:1  
为研究淮北矿区涡阳花沟西勘查区10号煤中微量元素的有机亲和性,共采集10个勘探钻孔煤样品,采用电感耦合等离子质谱仪ICP-MS分析了12种微量元素的含量;应用LECO碳硫分析仪测定了煤的总有机碳TOC,并通过两者的相关关系分析了元素的有机亲和性,结合元素的地球化学特征和煤样XRD物相鉴定结果,通过聚类分析进一步推断元素的赋存状态。结果表明:V、Cr、Co、Ni、Mo、Cd、Sb、Pb和Zn元素含量低于全国均值,没有异常富集,Be、Cu和Tl略高于全国均值;Cd具有较强的有机亲和性,Co、Zn、Be和Cr的有机亲和性较弱,V、Ni、Cu、Mo、Sb、Pb和Tl不具有机亲和性;V、Sb、Cu、Cr、Pb、Co和Ni主要以铝硅酸盐吸附态赋存,Cd主要以有机结合态赋存。   相似文献   

13.
This paper investigates the role played by the fumarolic plume of a passive degassing volcano in the genesis of rock coatings (RC) and in the introduction and re-distribution of metals and trace elements in the surficial environment. At La Fossa active volcano (Vulcano Island) and in the surrounding environment RC develop owing to exposure of the ground surface to the volcanic acid plume produced by the passive degassing of La Fossa. Significant positive anomalies of a wide variety of metals and trace elements (including Bi, Ag, Se, Te, Sb, Pb, As, Cu, Tl and Cd) were observed either in distal and proximal RC. Most of these anomalies are interpreted to be the result of the transport and subsequent deposition of trace elements, likely to form volatile compounds, in the fumarolic plume. Two main processes seem to control the geochemistry of RC: one is represented by the leaching and subsequent deposition of elements from the proximal toward the distal RC; the other is the direct input of trace elements carried by the emitted volcanic aerosol. The fact that most of the trace elements (particularly Pb, As, Tl, Bi, Te, Se, Cd) enriched in the RC of Vulcano are highly toxic and potentially dangerous to health in high concentration, indicates that the atmospheric metal injection by the quiescently degassing La Fossa volcano together with the subsequent deposition and remobilization by means of surficial waters may represent an environmental hazard that should be taken into account in evaluating the potential impact of volcanic air pollution on human health.  相似文献   

14.
《Applied Geochemistry》2005,20(8):1533-1545
Spring waters were analysed in the field by anodic stripping voltammetry, using equipment which is sufficiently portable to be useful in a remote heavily forested area accessible by foot only. The equipment and techniques are capable of producing analyses on site to the μg/L level for labile metals. Field analysis avoids issues of sample storage and transport protocols that limit confidence in laboratory measurements of labile elements. Samples were taken as a feedback to immediate analysis resulting in a fine grid map of the geological site. Acid rock drainage emanates from a New Zealand historic mine site, with elevated concentrations of metals. However, ground water and surface water discharging naturally from mineralised rocks in the same area also have elevated levels of metals. This study quantifies natural metalliferous discharges from a single site, and compares this to the overall metal flux from the mine area. Acid (pH 3) metalliferous springs emanate from colluvium and bedrock in a young (months-old) landslide. Labile Cu, Pb, Zn and Cd are the environmentally most significant metals in the studied area. Labile metal concentrations observed in the natural springs are up to 24 μg/L Cu, up to 50 μg/L Pb, up to 5 μg/L Cd and up to 9 mg/L Zn. Labile Cu and Zn concentrations are similar to laboratory-determined total concentrations, whereas labile Pb and Cd concentrations are generally distinctly lower than total Pb and Cd concentrations. Four different spring water compositions occur within metres of each other: acid metalliferous water with high Pb, acid metalliferous water with low Pb, high Cu, Pb, Zn acid water and high pH water with elevated Cu. High metal concentrations in these waters are readily attenuated by adsorption to Fe oxyhydroxides (HFO), especially when rain raises spring water pH at the surface. Copper, Pb and Cd are >99% adsorbed, and Zn >95% adsorbed, during this rainfall dilution. Natural spring waters have potential to contribute up to 10% of the total Zn flux from the catchment, but negligible proportions of Cu, Pb and Cd.  相似文献   

15.
Dissolved and particulate concentrations of metals (Fe, Al, Mn, Co, Ni, Cu, Zn, Cd, Tl, Pb) and As were monitored over a 5 year period in the Amous River downstream of its confluence with a creek severely affected by acid mine drainage (AMD) originating from a former Pb–Zn mine. Water pH ranged from 6.5 to 8.8. Metals were predominantly in dissolved form, except Fe and Pb, which were in particulate form. In the particulate phase, metals were generally associated with Al oxides, whereas As was linked to Fe oxides. Metal concentrations in the dissolved and/or particulate phase were generally higher during the wet season due to higher generation of AMD. Average dissolved (size < 0.22 μm) metal concentrations (μg/L) were 1 ± 4 (Fe), 69 ± 49 (Al), 140 ± 118 (Mn), 4 ± 3 Co, 6 ± 4 (Ni), 1.3 ± 0.8 (Cu), 126 ± 81 (Zn), 1.1 ± 0.7 (Cd), 0.9 ± 0.5 (Tl), 2 ± 3 (Pb). Dissolved As concentrations ranged from 5 to 134 μg/L (30 ± 23 μg/L). During the survey, the concentration of colloidal metals (5 kDa < size < 0.22 μm) was less than 25% of dissolved concentrations. Dissolved metal concentrations were generally higher than the maximum concentrations allowed in European surface waters for priority substances (Ni, Cd and Pb) and higher than the environmental quality standards for other compounds. Using Diffusion Gradient in Thin Film (DGT) probes, metals were shown to be in potentially bioavailable form. The concentrations in Leuciscus cephalus were below the maximum Pb and Cd concentrations allowed in fish muscle for human consumption by the European Water Directive. Amongst the elements studied, only As, Pb and Tl were shown to bioaccumulate in liver tissue (As, Pb) or otoliths (Tl). Bioaccumulation of metals or As was not detected in muscle.  相似文献   

16.
This paper reports a geochemical study of trace metals and Pb isotopes of sediments from the lowermost Xiangjiang River, Hunan province (P. R. China). Trace metals Ba, Bi, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, Mo, Cd, Sn, Sb, Pb, Tl, Th, U, Zr, Hf, Nb and Ta were analyzed using ICP-MS, and Pb isotopes of the bulk sediments were measured by MC-ICP-MS. The results show that trace metals Cd, Bi, Sn, Sc, Cr, Mn, Co, Ni, Cu, Zn, Sb, Pb and Tl are enriched in the sediments. Among these metals, Cd, Bi and Sn are extremely highly enriched (EF values >40), metals Zn, Sn, Sb and Pb significantly highly (5 < EF < 20), and metals Sc, Cr, Mn, Co, Ni, Cu and Tl moderately highly (2 < EF < 5) enriched in the river sediments. All these metals, however, are moderately enriched in the lake sediments. Geochemical results of trace metals Th, Sc, Co, Cr, Zr, Hf and La, and Pb isotopes suggest that metals in the river sediments are of multi-sources, including both natural and anthropogenic sources. Metals of the natural sources might be contributed mostly from weathering of the Indosinian granites (GR) and Palaeozoic sandstones (PL), and metals of anthropogenic sources were contributed from Pb–Zn ore deposits distributed in upper river areas. Metals in the lake sediments consist of the anthropogenic proportions, which were contributed from automobile exhausts and coal dusts. Thus, heavy-metal contamination for the river sediments is attributed to the exploitation and utilization (e.g., mining, smelting, and refining) of Pb–Zn ore mineral resources in the upper river areas, and this for the lake sediments was caused by automobile exhausts and coal combustion. Metals Bi, Cd, Pb, Sn and Sb have anthropogenic proportion of higher than 90%, with natural contribution less than 10%. Metals Mn and Zn consist of anthropogenic proportion of 60–85%, with natural proportion higher than 15%. Metals Sc, Cr, Co, Cu, Tl, Th, U and Ta have anthropogenic proportion of 30–70%, with natural contribution higher than 30%. Metals Ba, V and Mo might be contributed mostly from natural process.  相似文献   

17.
Weathering of heavy metal enriched black shales may be one of the most important sources of environmental contamination in areas where black shales are distributed. Heavy metal release during weathering of the Lower Cambrian Black Shales (LCBS) in western Hunan, China, was investigated using traditional geochemical methods and the ICP-MS analytical technique. Concentrations of 16 heavy metals, 8 trace elements and P were measured for samples from selected weathering profiles at the Taiping vanadium ore mine (TP), the Matian phosphorous ore mine (MT), and Taojiang stone-coal mine (TJ). The results show that the bedrock at these three profiles is enriched with Sc, V, Cr, Co, Ni, Cu, Zn, Pb, Th, U, Mo, Cd, Sb, Tl, and P. Based on mass-balance calculation, the percentages of heavy metals released (in % loss) relative to immobile element Nb were estimated. The results show significant rates of release during weathering of: V, Cr, Co, Ni, Cu, Zn, U, Mo, Cd, Sn, Sb, and Tl for the TP profile; Sc, Cr, Mn, Co, Ni, Cu, Zn, Pb, Th, Cd, and Sn for the MT profile; and Sc, Mn, Co, Ni, Zn, Th, Cd, Sn, and Tl for the TJ profile. Among these heavy metals, Co, Ni, Zn, Cd, and Sn show very similar features of release from each of the three weathering profiles. The heavy metals released during weathering may affect the environment (especially topsoil and surface waters) and are possibly related to an observed high incidence of endemic diseases in the area.  相似文献   

18.
土壤、岩石、水系沉积物等样品经盐酸、硝酸、氢氟酸、高氯酸敞开溶解,王水提取,试液直接用电感藕合等离子体质谱仪同时测定As、Sb、Bi、Li、Be、La、Ce、Sc、Co、Ni、Cu、Pb、Tl、U、Th、Cd、W、Mo、Zn等19种元素。方法检出限(σ=3)在0.03~5.0μg.g-1之间,所有元素的相对标准偏差(RSD,n=12)均小于10%,方法经国家一级地球化学标准物质验证,测定值与推荐值吻合。  相似文献   

19.
This study presents the concentrations and modes of occurrence of trace elements in 81 coal samples from the Çan basin of northwestern Turkey. The concentration of trace elements in coal were determined by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry. Additionally, traditional coal parameters were studied by proximate, ultimate, X-ray diffraction, and petrographic analyses. Twenty trace elements, including As, B, Ba, Be, Cd, Cu, Co, F, Hg, Mo, Ni, Pb, Sb, Se Sn, Th, Tl, U, V, and Zn, receive much attention due to their related environmental and human health concerns. The Çan coals investigated in this study are lignite to sub-bituminous coal, with a broad range of ash yields and sulphur contents. The trace element concentrations show variety within the coal seams in the basin, and the affinities vary among locations. The concentrations of B, Ba, Be, Cd, Cu, Co, F, Hg, Mo, Ni, Pb, Sb, Se, Sn, Tl, and Zn in Çan coals are within the Swaine's worldwide concentration range, with the exception of As, Th, U, and V. On the other hand, compared with world coals, the Çan basin coals have higher contents of As, B, Cu, Co, Mo, Pb, Th, U, V, and Zn. Based on statistical analyses, most of the trace elements, except for U, show an affinity to ash yield. Elements including As, Cd, Hg, Se, Cu, Mo, Ni, and Zn, show a possible association with pyrite; however, the elements Se, B, and Mo can be have both organic and inorganic associations.  相似文献   

20.
《Applied Geochemistry》2005,20(7):1258-1267
Distributions of 21 major and trace elements in HNO3 extracts of different horizons were studied in 13 podzol profiles from the boreal forest in different parts of Norway using ICP–MS. On the basis of ratios between the HNO3-extractable fractions in the various horizons some general trends were elucidated. Two different groups of elements concentrated in the humus layer relative to the mineral horizons were identified, one mainly associated with contributions from air pollution (As, Cd, Sb, Pb), another one with plant nutrient circulation (K, Ca, Mn and to a lesser extent Mg, Co, Ni, Rb) and some with both mechanisms (Cu, Zn, Tl). The elements most clearly enriched along with Fe in the B horizon were V, Pb, Al, and Cr in that order, Pb partly because of leaching from the polluted organic surface soil. Four soils in the far south showed a behaviour distinctly different from the rest and were treated as a separate group. Relative to the more northerly sites the surface horizons of these soils were strongly depleted in lithogenic elements (Mg, Al, K, Ca, Sc, V, Cr, Mn, Fe, Co, La) and enriched in elements typical of long-range transport of pollutants (As, Cd, Sb, Tl, Pb). Also the B horizon in the southern soils was strongly depleted in the lithogenic group elements, including Fe and the associated metals. The main reason for this difference is assumed to be the greater influence of transboundary air pollution and associated metals and stronger soil acidification in the far south of the country.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号