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1.
通过测定某铁尾矿库周边土壤中4种重金属元素(Cu、Cr、Pb、Cd)的含量及其形态特征,采用地累积指数法和次生相与原生相比值法(RSP法),探讨了研究区土壤重金属的污染程度。研究结果表明:土壤中重金属Cr、Cu、Cd的平均含量超过北京市土壤背景值,呈现一定的累积效应,重金属元素含量变化趋势为CrCuPbCd。除Cd元素外,其它重金属形态以残渣态为主,占比均为50%以上,各样品重金属酸可溶态(F1)的含量占比大小顺序为CdPbCuCr。评价结果显示75%样品中的Cr、58%的Cu和33%的Cd达到了轻度—中度污染;8%样品中的Cr和17%的Cu达到了中等污染;17%样品中的Cr达到了中等—强污染。区域内各个采样点中Cd元素污染风险较大,除Pb有一个点达到轻度污染风险外,其它Cr、Cu元素基本处于无风险的状态。研究区重金属元素污染风险大小的顺序为CdPbCuCr。  相似文献   

2.
研究目的】植物修复技术因其具有绿色、经济、环保的特点,在矿山生态修复中应用广泛,而调查和筛选矿山周边适应本地生境的植物物种是进行植物生态修复的关键环节。【研究方法】通过野外调查取样和室内分析测试相结合的方法,对内蒙古包头某废弃铁矿尾矿库及周边11种优势植物的重金属含量、重金属迁移富集能力及其上覆土壤重金属特征进行分析研究,以期筛选优良修复植物,为矿区生态修复提供科学依据。【研究结果】该废弃铁矿尾矿库及周边土壤Fe、Mn、Cu、Pb、Zn、Cr、Cd、F含量均远超过河套平原土壤背景值,地累积指数显示污染等级为2~7级,污染程度从轻—中度污染到极强度污染。植物地下部分各元素含量总体上高于地上部分,除Cu外各植物重金属含量大多超出了正常值范围。【结论】沙蒿和独行菜具有富集型植物特征,玉米、狗尾草、虎尾草和拂子茅属于根部囤积型,碱蓬、灰条菜、苍耳、新疆杨和红柳符合规避型植物特征。可根据植物对重金属的吸收和富集特点,科学合理地选择适宜的植物进行矿区受污染土壤植物修复。创新点:研究了废弃铁尾矿库及周边11种优势植物的重金属特征;揭示了优势植物对重金属的吸收机制。  相似文献   

3.
通过对铜陵凤凰山矿林冲尾矿库中重金属元素的空间分布特征及相关土壤、水系沉积物和植物中重金属元素含量变化的研究,初步了解尾矿重金属元素的空间变化和迁移规律,分析了其对周围环境的影响及潜在危害性,并指出了尾矿库土地综合开发利用的方向。  相似文献   

4.
矿业活动会促进重金属向生态系统扩散,并在周边农田土壤中累积而引发潜在生态风险。豫西金矿集区矿业生产历史悠久,但在长期的矿产资源开采、选冶、加工生产过程中,缺乏对矿区周边农田土壤重金属元素的累积、空间分布和生态风险的关注,矿业活动对环境的影响程度尚不清楚。为掌握该矿集区矿业活动对周边农田土壤重金属的影响程度,支撑服务矿集区生态修复和周边农业安全生产,本文在金矿集区周边农田采集375件土壤样品,采用冷蒸气原子荧光光谱法(CV-AFS)、氢化物发生原子荧光光谱法(HG-AFS)、电感耦合等离子体发射光谱/质谱法(ICP-OES/MS)检测了样品中Cu、Pb、Zn、Ni、As、Hg、Cd、Cr重金属元素含量。用地累积指数法和潜在生态风险指数法研究了矿集区周边农田土壤中重金属元素的累积特征、空间分布和生态风险,分析评价了矿集区矿业活动对周边农田土壤重金属的影响。研究结果表明:(1)矿集区周边农田土壤中Cu、Pb、Zn、Ni、As、Hg、Cd、Cr含量平均值都低于国家农田土壤重金属污染风险筛选值,但均高于背景值,分别是背景值的1.47、3.24、2.06、1.05、1.03、1.52、2.77、1...  相似文献   

5.
为掌握尤溪铅锌矿区土壤重金属元素分布特征和污染现状,通过采集尤溪铅锌矿不同功能区0~20cm表层土壤样品,测定土壤中Pb、Zn、Cd、Cu、Cr 5种重金属元素的总量及其化学形态,分析不同功能区土壤重金属污染及分布特征,同时采用次生相与原生相比值法(RSP)进行污染评价。结果表明,尤溪铅锌矿不同功能区土壤中Pb、Zn、Cd含量均超过国家土壤环境质量三级标准,废弃冶炼区土壤Cd、Cu、Pb、Zn含量均最高,分别为标准值的14.78、1.13、3.73、1.34倍,采矿区Cr含量最高,但未超过标准限值。重金属形态结果表明,相比其他元素,Cd弱酸提取态所占比例最高,Cu可交换态比例最高,Pb、Zn、Cr以残渣态为主。RSP法评价表明,不同重金属的污染程度表现为:Cu(1.15)Cd(0.80)Pb(0.59)Zn(0.57)Cr(0.54);不同功能区土壤重金属污染表现为:尾矿库区冶炼区废弃冶炼区采矿区。SPEF法评价表明,尤溪铅锌矿区受人为污染明显,采矿区和尾矿库区Zn污染最为严重,冶炼区和废弃冶炼区Pb污染最为严重,功能区污染顺序为:尾矿库区冶炼区废弃冶炼区采矿区。  相似文献   

6.
锂能源金属的战略地位不断提高,与锂矿床及锂金属相关的研究也在不断跟进,锂矿区土壤重金属污染近年来持续受到关注,其含量分布情况值得深入研究。本文对亚洲最大的锂矿区——川西甲基卡根系土壤环境进行重金属含量监测,调查和评价锂矿区土壤重金属含量水平及其安全性。2016—2018年于川西甲基卡锂资源富集区采集根系土壤样品68件,采用电感耦合等离子体质谱法(ICP-MS)测定根系土壤Cd、As、Pb、Cr、Cu、Ni、Zn含量。测试结果表明,甲基卡矿区根系土壤Cd、As、Pb、Cr、Cu、Ni、Zn含量平均值分别为0.13、15.31、25.47、60.57、16.12、23.59、66.83mg/kg,与2018年8月最新颁布的农用地土壤标准对比,无一超标,均低于风险筛选值及管制值。常见矿床的尾矿库区土壤一般存在严重的重金属污染,而甲基卡尾矿库土壤重金属含量均低于环境标准限值,且矿业活动停止的三年期间尾矿库区根系土壤中Cd、As、Cr含量明显呈逐年下降趋势。本研究认为,选矿厂房及尾矿库周边根系土壤重金属由于人为源的存在有一定的富集现象,但不构成危害,废弃物对环境污染小。  相似文献   

7.
武汉市东湖周边近地表土壤磁化率特征及其环境意义   总被引:4,自引:0,他引:4  
测量了武汉市东湖周边3个采样区60个土壤样品的磁化率及24个代表样品的重金属元素质量分数,对土壤磁化率和重金属元素质量分数进行了相关分析与聚类分析,探讨应用土壤磁化率参量及测量技术对大范围区域污染环境评价的指示意义.结果表明,土壤磁化率与重金属元素Ca、Cu、Pb、Sr、Zn质量分数显著相关,相关系数分别高达0.930,0.836,0.864,0.879和 0.879;重金属元素Ba、Cr、Fe、Mg、Mn质量分数与磁化率中度-弱相关,相关系数分别为0.447,0.303,0.557,0.528,0.333.聚类分析结果表明,不同采样区地表土壤的污染源之间存在一定差异.这些结果为应用土壤磁化率(尤其是原位磁化率)测量技术在该区进行大尺度和高精度环境评价提供了基础.  相似文献   

8.
韩娟娟  吴大鹏  张涛 《城市地质》2021,16(4):424-431
使用网格布点法采集144个浅层土壤样品,分析测定As、Cd、Cr、Cu、Hg、Ni、Pb和Zn共8种重金属元素的含量.通过多元统计方法、土壤重金属含量空间分布及极值点分析,揭示了金矿地区土壤污染特征及污染风险.结果显示,区内浅层土壤重金属含量超过该地区背景值较高的元素为Pb、As、Cd,与背景值接近的元素为Cr与Ni.重金属污染风险较高的区域集中分布在金矿开采区、尾矿库、选矿厂及其下游约1.5 km范围内,主要污染元素为As、Cd、Pb、Cu、Zn,基本不存在Cr、Ni、Hg污染.相关性与主成分分析结果显示,矿山开采及冶炼是土壤重金属污染的主要来源.污染物的主要迁移途径为金矿开采区、尾矿库及选矿厂的废渣和尾矿析出的重金属通过废渣及尾矿堆的孔隙下渗进入底垫土壤,通过地表径流进入下游土壤中.  相似文献   

9.
韩娟娟  吴大鹏  张涛 《城市地质》2021,16(4):424-431
使用网格布点法采集144个浅层土壤样品,分析测定As、Cd、Cr、Cu、Hg、Ni、Pb和Zn共8种重金属元素的含量.通过多元统计方法、土壤重金属含量空间分布及极值点分析,揭示了金矿地区土壤污染特征及污染风险.结果显示,区内浅层土壤重金属含量超过该地区背景值较高的元素为Pb、As、Cd,与背景值接近的元素为Cr与Ni.重金属污染风险较高的区域集中分布在金矿开采区、尾矿库、选矿厂及其下游约1.5 km范围内,主要污染元素为As、Cd、Pb、Cu、Zn,基本不存在Cr、Ni、Hg污染.相关性与主成分分析结果显示,矿山开采及冶炼是土壤重金属污染的主要来源.污染物的主要迁移途径为金矿开采区、尾矿库及选矿厂的废渣和尾矿析出的重金属通过废渣及尾矿堆的孔隙下渗进入底垫土壤,通过地表径流进入下游土壤中.  相似文献   

10.
矿山开采及冶炼所产生的废渣是矿区土壤重金属污染的主要因素。为了准确掌握遵义锰矿区土地的污染程度,以表观污染程度作为标准,分别采集土壤样品进行分析测试,采用地累积指数法及生态危害指数法分别评价不同区域的污染程度及生态危害程度。研究结果表明:遵义锰矿区农用地土壤中As、Cd、Cr、Cu、Hg、Mn、Ni、Pb、Zn等9种元素背景值略高于贵州全省背景值,除Mn元素外,其他元素未发现明显聚集现象,而矿渣堆、尾矿库附近土壤中存在重金属元素聚集,且Mn、Cd存在明显聚集;地累积指数评价结果:农用地土壤样品中极少量的As、Cd达中度至重度污染程度,矿渣堆、尾矿库附近土壤20%样品Cd达到了中度至重度污染水平;生态危害指数评价结果为农用地中主要由于Cd、Hg、As元素残留导致生态环境风险,风险等级为较强风险;废渣堆、尾矿库附近土壤则主要由于Cd、Hg元素残留导致生态环境风险,风险等级为极强风险。  相似文献   

11.
Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.  相似文献   

12.
最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提  相似文献   

13.
This paper reports the first results of a study of 11 isotope systems (3He/4He, 40Ar/36Ar, 34S/32S, 65Cu/63Cu, 62Ni/60Ni, 87Sr/86Sr, 143Nd/144Nd, 206–208Pb/204Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.  相似文献   

14.
本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。  相似文献   

15.
本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。  相似文献   

16.
Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.  相似文献   

17.
18.
Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

19.
《Applied Geochemistry》2001,16(2):137-159
Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km2 area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).  相似文献   

20.
We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al2O3-SiO2 ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.  相似文献   

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