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1.
对不同离子交换柱、淋洗体积、盐度、分离次数等一系列影响铜、锌纯化分离效果的条件进行了探讨,确定了环境样品(湖泊沉积物、植物和颗粒物)中铜、锌同位素测定时化学分离的最佳条件。采用AGMP-1(100～200目)阴离子交换树脂,以7mol/LHCl+0.001%H2O2、2mol/LHCl+0.001%H2O2、0.5mol/LHNO3作为淋洗液,分别在适当的体积接收淋洗液,可以有效地分离沉积物、植物和悬浮物等样品中的铜和锌。化学分离过程中Cu和Zn的回收率接近100%,同位素分馏在测试误差范围以内。将此方法应用于对红枫湖和阿哈湖水体悬浮物、植物和鱼类等样品中Cu、Zn的分离,经MC-ICP-MS测试后,准确获得了这些样品的Cu、Zn同位素组成。 相似文献
2.
螯合作用是植物对细胞内重金属耐受的主要方式之一,植物中螯合肽(PCs)在植物耐重金属毒害中的作用已有许多报道,但作用程度并未得出一致的结论,关于PCs是在镉刺激下直接合成还是以谷胱甘肽为底物合成同样存在争议.本文研究了胁迫浓度和胁迫时间对超积累植物印度芥菜(Brassica juncea)中镉形态分布的影响.印度芥菜幼苗分别用0.5、1.0、3.0、5.0、10.0 mg/L镉标准溶液胁迫24 h、48 h、72 h、96 h后收获,用体积排阻高效液相色谱-电感耦合等离子体质谱技术测定植物体根部和叶部中镉形态的含量.结果表明,在低胁迫浓度下(≤3.0 mg/L),植物叶中PCs-Cd的含量与胁迫浓度成正比;在高胁迫浓度下,PCs-Cd含量反而降低,根中PCs-Cd的含量持续增加,但叶中PCs-Cd总量高于根部,说明PCs在植物体内会由根部向叶部转移,从而提高了镉耐受性.在持续长时间胁迫下,PCs-Cd含量也降低,表明PCs在镉解毒机制中仅有短暂的作用;持续高浓度胁迫下,植物会引发其他机制来抵制Cd的毒性.研究认为PCs在镉解毒机制中的作用需要考虑胁迫时间和胁迫浓度这两个重要参数. 相似文献
3.
基于前期调查,采集水稻籽实样品共50件,在选定的3处地块采集9组土壤和水稻组合样品,每组样品包括根系土、水稻根系、水稻茎和籽实,分析其各部位的重金属元素含量,探究重金属元素在植物不同部位的迁移与富集机理。研究区水稻不同部位的元素富集规律为根系富集系数F(As)＞F(Cu)＞F(Cd)＞F(Zn)≈F(Hg)＞F(Cr)≈F(Ni)≈F(Pb),茎部富集系数F(Hg)＞F(Zn)≈F(Cu)＞F(Cd)＞F(As)＞F(Cr)＞F(Ni)＞F(Pb),籽实富集系数F(Zn)＞F(Cu)＞F(Cd)＞F(Ni)＞F(As)≈F(Cr)＞F(Pb),水稻植株内重金属元素含量分布规律为根系＞＞茎＞籽实。重金属元素在该系统中的迁移系数和迁移模式可分为4类。研究结果对土壤环境修复与合理利用等有一定的借鉴意义。 相似文献
4.
北京城区土壤中Hg、Pb、Cd、Cu及Zn化学形态及环境效应 总被引：1，自引：0，他引：1
为弄清北京城区土壤中Hg、Pb、Cd、Cu及Zn五种重金属元素的化学形态分布特征,系统采集了126件城区表层土壤样品,采用连续提取法对重金属元素各化学形态含量进行了测定。结果表明:土壤中土壤中Hg、Pb、Cd、Cu、Zn含量差异显著。Hg元素以残渣态和强有机结合态为主,Cd元素离子交换态、碳酸盐结合态、残渣态、铁锰氧化物结合态含量较高,Pb、Cu、Zn元素以残渣态、铁锰氧化物结合态为主。Hg元素的有效态含量最低(不足1%),现情况下不会对环境造成污染;Cd元素的有效态含量最高(40%),生物有效性和潜在生态危害性较大,运用植物修复技术对其治理为经济有效的方法;Pb、Cu、Zn有效态含量较低(约10%),生物有效性和潜在生态危害性均有限。各元素形态与全量之间相关程度虽有差别,但基本呈正相关关系。 相似文献
5.
6.
纳雍枝铅锌矿床是贵州省内发现的第一个大型铅锌矿床,前人对该矿床进行过大量地质和地球化学研究,对该矿床成因有了一定认识,但其成矿金属来源,特别是其中稀散金属(如Cd)的来源却少有涉及。本文分析了该矿床硫化物和精矿样品的微量元素及镉同位素组成,结合该区域不同地质端元的地球化学数据,来探讨以Cd为代表的稀散金属来源。结果表明,样品的Zn/Cd值变化较大(377～953),均高于川滇黔地区沉积岩的Zn/Cd比值(13～367),而更接近火成岩的Zn/Cd值(515～1319)。精矿和闪锌矿样品的镉同位素组成(δ114/110Cd NIST-3108)变化范围极小(-0.09‰～-0.05‰),与已获得的岩浆岩数据一致(-0.22‰～0.15‰),但明显区别于该地区的碳酸盐岩地层(-0.25‰～0.82‰)。结合精矿的Zn/Cd-δ114/110Cd NIST-3108关系图解和前人研究成果,本文认为该矿床金属成矿物质(如镉、铅等)主要来自基底。 相似文献
7.
TGQ-15型轻便取样钻机钻具改进实验及其应用 总被引：1，自引：0，他引：1
结合北京市土壤地质环境情况,改进以钻代槽(浅层钻探技术)。选取TGQ-15型轻便取样钻机,在北京市平原区、山区共开展两种类型改进应用实验,即取样管改进应用实验和取样管外部刻度尺改进应用实验。在河床沉积区、河床一级阶地和山前坡积区,3种不同的区域选择不同的方法采集样品分析测试。结果表明:经过不同材质对比以及样式设计的有机玻璃管用来取样及存储土壤样品是安全的,并且土壤中的重金属含量不会受到影响;通过对3个不同地貌单元的分析评价后得出结论,钻机采取垂直样品过程中,Cu(铜)、Zn(锌)、Pb(铅)、Cr(铬)、Ni、Cd(镉)、AS(砷)和Hg的含量未受影响,其分析评价结果可以反应取样区域的污染状况;经过改进设计的刻度尺,提高了孔深校正的效率和精度,同时便于地质地层的编录。总之,钻机的改进避免了土壤的人为污染,提高了土壤样品质量,同时提高了取样效率。 相似文献
8.
基于形态学分析铅锌矿不同功能区土壤重金属元素的分布特征及污染评价 总被引：1，自引：1，他引：0
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
9.
本文基于2002—2022年期间,知网、万方、Web of Science数据库收录的矿区周边土壤重金属文献数据,采用Meta分析方法,探讨我国不同地区和矿种类别的矿山开采对土壤重金属分布特征的影响。同时,结合地累积指数法和潜在生态风险指数法评估矿区周边土壤重金属生态风险。Meta分析结果显示,我国矿区周边土壤中镉(Cd)、汞(Hg)、铜(Cu)、铅(Pd)、锌(Zn)、砷(As)、镍(Ni)和铬(Cr)的浓度相较于土壤背景值,分别增加了820.7%、309.6%、158.6%、158.6%、146.0%、103.4%、24.6%和15%,其中,Cd和Hg增加量较多。从地区来看,中南和西南地区的矿区周边土壤重金属的效应值较大,其重金属浓度增加量分别为285.7%和180.1%,其中西南、中南和华东地区矿山周边土壤中Cd、Hg、Zn、Pb和Cu的含量增加较为显著,华北和东北地区的Cd和As、西北地区的Cd和Hg增加较为显著。从矿种类型看,铅锌矿、多金属矿、铜矿、金矿、汞矿、钼矿、锰矿、锡矿和包含石墨矿等其他矿种的周边土壤重金属浓度增加量为166.4%～617.1%,其中铅锌矿开采会使得C... 相似文献
10.
11.
Yongcun Zhao Xianghua Xu Jeremy Landon Darilek Biao Huang Weixia Sun Xuezheng Shi 《Environmental Geology》2009,57(5):1089-1102
Topsoil samples (0–20 cm) (n = 237) were collected from Rugao County, China. Geostatistical variogram analysis, sequential Gaussian simulation (SGS),
and principal component (PC) analysis were applied to assess spatial variability of soil nutrients, identify the possible
areas of nutrient deficiency, and explore spatial scale of variability of soil nutrients in the county. High variability of
soil nutrient such as soil organic matter (SOM), total nitrogen (TN), available P, K, Fe, Mn, Cu, Zn, and B concentrations
were observed. Soil nutrient properties displayed significant differences in their spatial structures, with available Cu having
strong spatial dependence, SOM and available P having weak spatial dependence, and other nutrient properties having moderate
spatial dependence. The soil nutrient deficiency, defined here as measured nutrient concentrations which do not meet the advisory
threshold values specific to the county for dominant crops, namely rice, wheat, and rape seeds, was observed in available
K and Zn, and the deficient areas covered 38 and 11%, respectively. The first three PCs of the nine soil nutrient properties
explained 62.40% of the total variance. TN and SOM with higher loadings on PC1 are closely related to soil texture derived
from different parent materials. The PC2 combined intermediate response variables such as available Zn and P that are likely
to be controlled by land use and soil pH. Available B has the highest loading on PC3 and its variability of concentrations
may be primarily ascribed to localized anthropogenic influence. The amelioration of soil physical properties (i.e. soil texture)
and soil pH may improve the availability of soil nutrients and the sustainability of the agricultural system of Rugao County. 相似文献
12.
Munendra Singh 《Environmental Geology》2001,40(6):664-671
The Yamuna River sediments, collected from Delhi and Agra urban centres, were analysed for concentration and distribution
of nine heavy metals by means of atomic adsorption spectrometry. Total metal contents varied in the following ranges (in mg/kg):
Cr (157–817), Mn (515–1015), Fe (28,700–45,300), Co(11.7–28.4), Ni (40–538), Cu (40–1204), Zn (107–1974), Pb (22–856) and
Cd (0.50–114.8). The degree of metal enrichment was compared with the average shale concentration and shows exceptionally
high values for Cr, Ni, Cu, Zn, Pb and Cd in both urban centres. In the total heavy metal concentration, anthropogenic input
contains 70% Cr, 74% Cu, 59% Zn, 46% Pb, 90% Cd in Delhi and 61% Cr, 23% Ni, 71% Cu, 72% Zn, 63% Pb, 94% Cd in Agra. A significant
correlation was observed between increasing Cr, Ni, Zn, and Cu concentrations with increasing total sediment carbon and total
sediment sulfur content. Based on the Müller's geoaccumulation index, the quality of the river sediments can be regarded as
being moderately polluted to very highly polluted with Cr, Ni, Cu, Zn, Pb and Cd in the Delhi and Agra urban centres. The
present sediment analysis, therefore, plays an important role in environmental measures for the Yamuna River and the planning
of these city centres.
Received: 21 June 1999 · Accepted: 1 October 1999 相似文献
13.
Mercury and other metal and metalloid soil contamination near a Pb/Zn smelter in east Hunan province, China 总被引：6，自引：0，他引：6
Zhonggen LiXinbin Feng Guanghui LiXiangyang Bi Guangyi SunJianming Zhu Haibo Qin Jianxu Wang 《Applied Geochemistry》2011,26(2):160-166
The spatial distributions of contaminant metals (Hg, Pb, Zn, Cd, Cu) and a metalloid (As) in vegetable plots and paddy fields located near a large scale Pb/Zn smelter in Hunan province, China, were investigated. Soil located 4 km from the smelter was severely contaminated, with maximum concentrations of Hg, Pb, Zn, Cd, Cu and As as high as 2.89, 1200, 3350, 41.1, 157 and 93 mg kg−1, respectively. Concentrations of soil metal and As decreased with distance in the dominant wind direction. Single-factor assessment indicated pollution levels of Hg, Pb, Zn and Cd were most severe, while pollution levels for Cu and As were less severe. Results from a potential ecological risk assessment indicated high risk associated with the soil within a 4 km radius, with the contribution for each contaminant calculated as follows: Cd (70.0%), Hg (19.4%), Pb (4.8%), As (3.0%), Cu (1.7%) and Zn (1.1%). The forest soil in the nearby city park was also affected by the atmospheric depositions from smelting activities. Soil profiles demonstrated the pollutants were mostly accumulated in the upper 20 cm layer. Contamination of the topsoil with Hg, Pb, Zn, Cd, Cu and As indicated remediation should be considered. 相似文献
14.
AB-DTPA提取法在重金属污染土壤修复模拟试验中的应用可行性 总被引：2，自引：0，他引：2
将碳酸氢铵-二乙三胺五乙酸(AB-DTPA)提取重金属生物有效态的方法应用于重金属污染土壤修复的模拟试验中,该土壤的污染元素主要是铜、锌和镉,试验所用修复材料是钠化膨润土。研究表明,AB-DTPA提取法具有很好的稳定性,而且能准确指示铜、锌、镉元素在土壤中的有效态含量,同时AB-DTPA对土壤中铜、锌、镉元素的提取率也适用于模拟试验中修复效果的平行对比。AB-DTPA提取法在重金属污染土壤修复模拟试验中的应用是可行的。 相似文献
15.
A total of 29 surface sediments were collected from the Daihai Lake, China. Concentrations of metals (Cu, Pb, Zn, and Cd) were determined using HR-ICP-MS after digestion with the mixture of HNO3–HF–HCl (aqua regia), and chemically fractionated according to the modified the European Community Bureau of Reference sequential extraction procedure. Total organic carbon contents and grain size were also analyzed. Average concentrations (ppm) for Cu (39.4 ± 10.6), Pb (29.9 ± 6.1), Zn (102.6 ± 23.3), and Cd (0.21 ± 0.07) were found in the sediments. The concentrations of metals are relatively higher in the central area of lake, while lower nearby the area with a shallower water depth. Sequential extraction results show that Cu and Zn are mainly distributed in the residual fraction, while Cd is dominantly in the non-residual fraction. Enrichment factor values and geoaccumulation indexes suggest that there are not obvious enrichments of Cu, Pb, and Zn in the sediments, but Cd pollution can be found in most of the area of Daihai Lake. The sources for Cu, Pb, and Zn are attributed to atmospheric deposition, which might be mainly associated with coal combustion. Agricultural runoff in polluted soils and coal combustion might be main sources of the Cd pollution in the lake. 相似文献
16.
Immobilization of heavy metals in a contaminated soil in Iran using di-ammonium phosphate,vermicompost and zeolite 总被引：2，自引：0，他引：2
Fractionation of heavy metals (HMs) in amended soils is needed to predict elemental mobility in soil and phytoavailability
to plants. A study was conducted to determine the effects of different amendments on HMs availability and their redistribution
among soil fractions. A contaminated soil was selected from around a Zn mine and amended with 0, 2, 4, and 6 g kg−1 of vermicompost (VC), zeolite (ZE), and di-ammonium phosphate (DP) and incubated at field moisture. The amounts of Cd, Pb,
Zn, and Cu were determined from the soil after 6 months of incubation time using DTPA and sequential extraction procedures.
The total concentrations of Cd, Pb, Zn, and Cu were 41, 3,099, 1,997, and 83 mg kg−1 of soil, respectively. All amendments decreased significantly [probability (p) ≤ 0.05] DTPA-extractable Cd, Pb, and Cu, but not Zn, in the soil. For instance, DTPA-extractable Cd, Pb, and Cu decreased
by 40, 290, and 20%, respectively, and that of Zn increased by 18% with DP1 (2 g kg−1 of di-ammonium phosphate) application. The concentrations of Pb and Cd decreased mainly in the specifically sorbed (SS) but
increased in the amorphous Fe oxide (AFeO) fraction with DP application, indicating redistribution of Pb and Cd in the fractions
with less mobility. Lead immobilization by DP was mainly attributed to the P-induced formation of chloropyromorphite, which
was identified in the DP treatment using X-ray diffraction technique. It was concluded that DP was the most effective amendment
in immobilizing Pb and Cd, though it increased Zn mobility. 相似文献
17.
Assessment of heavy metal pollution in surface water 总被引：4，自引：3，他引：1
D. Kar M.Sc. P. Sur M.Sc. S. K. Mandai M.Sc. T. Saha M.Sc. R. K. Kole M.Sc. 《International Journal of Environmental Science and Technology》2008,5(1):119-124
A total of 96 surface water samples collected from river Ganga in West Bengal during 2004–05 was analyzed for pH, EC, Fe, Mn, Zn, Cu, Cd, Cr, Pb and Ni. The pH was found in the alkaline range (7.21–8.32), while conductance was obtained in the range of 0.225–0.615 mmhos/cm. Fe, Mn, Zn, Ni, Cr and Pb were detected in more than 92% of the samples in the range of 0.025–5.49, 0.025–2.72, 0.012–0.370, 0.012–0.375, 0.001–0.044 and 0.001–0.250 mg/L, respectively, whereas Cd and Cu were detected only in 20 and 36 samples (0.001–0.003 and 0.003–0.032 mg/L). Overall seasonal variation was significant for Fe, Mn, Cd and Cr. The maximum mean concentration of Fe (1.520 mg/L) was observed in summer, Mn (0.423 mg/L) in monsoon but Cd (0.003 mg/L) and Cr (0.020 mg/L) exhibited their maximum during the winter season. Fe, Mn and Cd concentration also varied with the change of sampling locations. The highest mean concentrations (mg/L) of Fe (1.485), Zn (0.085) and Cu (0.006) were observed at Palta, those for Mn (0.420) and Ni (0.054) at Berhampore, whereas the maximum of Pb (0.024 mg/L) and Cr (0.018 mg/L) was obtained at the downstream station, Uluberia. All in all, the dominance of various heavy metals in the surface water of the river Ganga followed the sequence: Fe > Mn > Ni > Cr > Pb > Zn > Cu > Cd. A significant positive correlation was exhibited for conductivity with Cd and Cr of water but Mn exhibited a negative correlation with conductivity. 相似文献
18.
未定名硫化物矿物是一个稀少矿物，它发现于内蒙古铅锌矿的钛卡岩矿床中。共生太物有黄铜矿、闪锌矿、方铅矿。它呈黑色，金属光泽，不透明，硬度为165－214kg/mm^2。反射铯为灰色微带蓝色，弱非均质性，深蓝－－黄褐色。化学成分（wt%）：S32.32、Cu6.46、Fe6.56、Zn54.29、Pb0.31、Cd0.2c、CO0.03（平均），分子式(Zn0.84Fe0.11Cu0.09)1.04S。X射线分析数据与闪锌矿相同，d值和晶胸参数比闪锌矿（含铁）的小，晶胞参数比人工合成闪锌矿的大。粉晶主要强线为3.108(100)、1.906(50)、1.628(30)、1.240(20)、1.103(20)。 相似文献
19.
土壤重金属含量是影响黄芩产量和质量的重要因素。选取承德市中部金沟屯和五道岭两处黄芩种植示范区为研究区,采集表层土壤样品355件,黄芩样品30件,重金属形态样品15件。在分析土壤Mn、Zn、Cu、Cr、Cd、As、Pb、Ni、Hg、V、Co、Sb和土壤有机质含量（SOM）及pH值,黄芩Zn、Cu、Cr、Co、Cd、Pb、Ni、Hg和As含量基础上,采用描述性统计、地累积指数、主成分和RDA分析、重金属生物富集系数、生物活性系数和迁移系数等方法论述了土壤-黄芩系统重金属生物有效性及迁移累积特征。结果表明:金沟屯和五道岭区土壤各重金属累积程度总体属无-中度累积水平。五道岭Cu和Hg累积程度高于金沟屯区,其它元素累积程度低于金沟屯区。五道岭区表层土壤Cr、Cu和Cd含量超标率分别为2.82%、1.69%和1.13%;金沟屯区土壤Cd、Cr和Ni,五道岭区土壤Zn和Hg含量超标率均为0.56%。五道岭区黄芩Cu元素含量高于金沟屯区,Co和Cu元素生物富集强度高于金沟屯区,其它元素含量和生物富集强度则均低于金沟屯区。土壤Cd和Hg元素生物活性系数相对最高,Ni、Zn和Pb元素次之,Cu、Cr和As生物活性系数相对较低。金沟屯区根系土具有较低的pH值和较高的SOM含量,区内黄芩根部As、Cd、Cr、Ni、Zn和Pb元素BCF平均值高于五道岭区,Cu元素富集强度低于五道岭区。土壤重金属生物有效性和黄芩重金属生物富集强度受土壤pH和SOM含量影响,其中Cd和Cu元素受SOM含量影响最为明显。 相似文献
20.
为探讨渤海西部在多重环境因素变化下沉积物中重金属的环境地球化学行为,分析了渤海西部44个站位表层沉积物样品中8种重金属元素含量,研究了重金属元素的分布特征、环境影响因素及其生态风险。结果表明,渤海西部表层沉积物中As、Cu、Cd、Cr、Hg、Ni、Pb、Zn的平均含量分别为117 mg/kg、255 mg/kg、014 mg/kg、689 mg/kg、0037 mg/kg、303 mg/kg、223 mg/kg、757 mg/kg;Cu、Cr、Ni、Zn含量与有机碳含量、小于63 μm细粒沉积物呈显著正相关,其在表层沉积物中的分布明显受到有机质含量和沉积物粒径的控制,而As、Hg分布没有明显受到有机质含量的影响。富集系数显示,Cr、Ni、Pb和Zn为无富集,Cu、As为轻度富集,Cd和Hg为中度富集。与多种背景值和一致性沉积物质量基准相比较,渤海西部表层沉积物Pb、Cd的含量超出背景值,而Cu、Zn、Ni、Cr、As、Hg含量也存在一定的异常,但其含量水平引发有害生物效应的可能性不大,尽管重金属元素含量偏高,但生态风险较小。 相似文献