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1.
安徽栏杆地区碱性基性岩岩性为橄榄辉长岩,微量元素特征表现为大离子亲石元素(K、Rb、Sr、Th和Ba)富集,但高场强元素(Nb、Ta、Zr和Hf)无明显亏损,表明岩石形成于大陆板内环境,为地幔低度部分熔融的产物;稀土元素特征表现为LREE强烈富集,而HREE相对亏损,暗示了源区富集特征,Eu负异常显示岩浆经历了明显的斜长石结晶分异。结合中国东部碱性基性岩的金刚石成因条件及地球化学特征分析,认为本区碱性基性岩具有金刚石成矿地质条件。  相似文献   

2.
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County, Yunnan Province, South-West China. The area was divided into three di erent geomorphological units: specifically, mountain (M), transition (T) and lacustrine (L). Mean trace element content in subsoil were determined for Pb (58.2 mg/kg), Cd (0.89 mg/kg), Cu (129.2 mg/kg), and Zn (97.0 mg/kg). Strong significant relationships between trace element content in topsoil and subsoil were observed. Both Pb and Zn were accumulated in topsoil (RTS (ratio of mean trace element in topsoil to subsoil) of Pb and Zn >1.0) and Cd and Cu in subsoil (RTS of Cd and Cu 61.0). Subsoil trace element content was related to relief, stoniness, soil color, clay content, and cation exchange capacity. Except for 7.5 YR (yellow-red) color, trace element content increased with color intensity from brown to reddish brown. Significant positive relationships were observed between Fe content and that of Pb and Cu. Trace element content in mountain unit subsoil was higher than in transition and lacustrine units (M > T > L), except for Cu (T > M > L). Mean trace element content in calcareous subsoil was higher than in sandstone and shale. Mean trace element content in clay texture subsoil was higher than in sandy and sandy loam subsoil, and higher Cu and Zn content in subsoil with few mottles. It is possible to model Pb, Cd, Cu, and Zn distribution in subsoil physico-chemical characteristics to help improve agricultural practice.  相似文献   

3.
The inventory of profile distribution of total iron(Fe),zinc(Zn), manganese(Mn) and copper(Cu) were determined in three different soil horizons each of the wetland soils selected form Mbiabet(MB),Nkari(NK)and Nkana(NA) in Ini Local Government Area of Akwa Ibom State.Total Fe ranged between 3.25 and 4.15ppm.The average contents were 3.72,3.91 and 3.62ppm in Mbiabet(MB),Nkari(NK) and Nkana(NA)soils respectively.The total value of Zn also ranged between 2.4 and 4.9 ppm with the average content in each soil being 28.27,17.73and 36.53 ppm respectively.The amount of Fe and Zn in these soil profiles were strongly correlated with the clay content and high levels of organic matter of 3.70%,2.47%and 2.5% respectively.The content clearly reflected a poor drainage conditions.In all the soil profiles Mn and Cu were detected in at least one of the soil horizons.However, Mn and Cu were not detected in the soil horizons at Nkari.Generally , the relative inventory of these micronutrients appeared to be influenced by pH,drainage pattern,organic matter and clay contents of these soils.The inventory of total values of the wetland soils considered are assessed in the light of establishing a baseline information.  相似文献   

4.
根据110余个表层土壤样品硼、锰含量的测定结果和土壤缺乏硼、锰的临界值指标,探究了川西北草原土壤中硼、锰的有效性及其丰缺状况.结果表明,本区土壤中全硼全锰含量丰富分别达166.0ppm和736.6ppm,但有效硼和锰的含量仅分别为0.45ppm和5.11ppm,土壤缺乏硼和锰比较普遍.为该区推广施用硼、锰微肥提供了初步的科学依据.  相似文献   

5.
烟草,土壤中涕灭威总有毒残留分别用丙酮、丙酮与水混合液提取,过氧乙酸氧化,液-液分配和柱层析净化后,气相色谱检测。方法回收率在83~105%之间,土壤、鲜烟叶和干烟叶中的最小检出浓度分别为0.0135ppm,0.0169ppm和0.0339ppm。   相似文献   

6.
使用USEPA Method 29方法对600MW燃煤电厂SCR、ESP和WFGD前后4个测点进行烟气痕量元素同时取样,研究了12种痕量元素(Cr、Mn、Co、Ni、Cu、Zn、As、Mo、Cd、Sb、Ba、Pb)的排放特性.结果表明:整个电厂系统、锅炉、SCR、ESP和WFGD中痕量元素的质量平衡率都在可接受范围内,实验结果准确可靠.这12种痕量元素主要分布于ESP飞灰中,相对分布率为69.97%~98.79%.底渣中痕量元素的相对富集指数在0.04~0.51之间,ESP飞灰中痕量元素的相对富集系数在0.3~1.23之间.ESP飞灰中的As、Cd和Pb以及WFGD废水中的Mn、Co和Ni可能会对土壤和地下水产生污染,需要引起关注.12种痕量元素向大气中的排放浓度位于0.02~12.57μg/m3之间,排放因子位于的0.01~2.13g/1012J之间,Ni、As、Cd和Pb这4种元素的排放浓度分别达到2.04、0.13、0.02和3.35μg/m3,都远超欧盟空气质量标准中的排放限值,需要加以重视进行限制.  相似文献   

7.
利用电感耦合等离子体质谱(ICP-MS)研究了胶州湾及莱州湾这两个海域中痕量元素污染水平,发展了ICP-MS海水环境中痕量元素的测定方法,同时找出海水环境中具有保守性的数种元素作为污染示踪元素.达到对于海水环境中痕量污染物被动示踪的目的.对18个真实样品进行了识别率试验,识别率可达90%以上,在选取3个海水样品及1个河水样品混合后的模拟分担率实验,也取得了满意的结果,其误差平均值仅有1.17%.  相似文献   

8.
通过不同施药方法,探讨了林丹在小麦、玉米中的残留水平。结果表明,林丹在作物中的残留量随施药量的增加而递增。采用喷雾,4(a.i.)g/亩,林丹在小麦中的残留为0.0073ppm;土壤处理,100(a.i.)g/亩,林丹在小麦中的残留为0.0134ppm;撒颗粒剂,0.015(a.i.)g/株,林丹在玉米中的残留为0.0600ppm.林丹在土壤中消解很快,当土壤处理[200(a.i.)g/亩],林丹在土壤中的半衰期为23.7~25.2d,消解99%需160d左右。作者认为,在我国部分害虫防治中起用林丹不可能对生态环境构成威胁。   相似文献   

9.
天津地区土壤中微量元素含量的纵向分异   总被引:15,自引:0,他引:15  
根据80个土壤剖面13种微量几素及有关理化参数实测结果,研究了大津地区土壤中微量元素含量的纵向分异结果表明,天津土壤中绝大多数微量元素含量高于全国平均含量由于淋溶较弱,发育时间较短,各微量元素含量在土壤纵向的分异不明显与受市区影响较小的远郊相比,天津近郊土壤中各微量元素含量具有明显的升高趋势,其中汞的增幅最大大津地区冲积母质土壤中微量元素含量与残积母质土壤中相应含量的比值大多在1~15之间。冲积过程中的粒径分选作用是形成这一现象的根本原因空间分析的结果证明,母质是影响天津土壤中微量元素含量的主导因素,面人为影响也一定程度上改变了土壤中微量元素含量及其空间分布  相似文献   

10.
An one-year of sampling aerosol program was carried out during the period of April 1995 to April 1996 at coastal region, Cape D‘Aguilar, in Hong Kong. The trace element composition of aerosol particles(TSP and PM10) were measured and analyzed by using the Instrumental Neutron Activation Analysis(INAA) and Inductive Couple Plasma-Mass Spectrometry(ICP-MS) techniques. The results showed that the polluted elements such as: V, Zn, As, Pb, Cd, Sb, I, Se, Bi, with high enrichment factor( E. F) values, are derived from anthropogenic sources ,while Sc, AI, Fe, Mn, Sm, La, Sr are less than 10 in E. F, these elements are related the crust and soil. The concentration of the trace elements are present seasonal variation i.e. summer low and winter high, whereas the V or noncrustal V(V^* ) present summer high and winter low, this phenomenon might be explained by local or regional oil combustion sources. Use three type of elemental ratio, e.g. La/Sm, Mn^*/V^* and Bi/Al indicate that both TSP and PM10 of La/Sm ratios are mainly related to soil and dust, Mn^*/V^* are probably represent fossil combustion and Bi/Al are possibly associated with refuse incineration, ferromanganese alloys and aluminum production. The varimax rotation factor analysis for trace elements was performed. By means of the absolute principal component analysis (APCA) and multiple regression, the contribution of trace elements to possible sources and overall means of trace elements were estimated. The results showed that the present station is impacted by the anthropogenic species, although the quantities are different during the summertime and wintertime.  相似文献   

11.
为了解三七中Fe、Mn、Al、Zn、Se人体微量元素的含量,并客观评价这5种微量元素对长期服用三七药品的患者的健康风险,在三七的产区及周边市县进行采样,采用电感耦合等离子体质谱仪(ICP-MS)对三七中这5种微量元素的含量进行测定,并采用点推定和概率推定对各元素的非致癌风险危害商值(HQ)值进行评估,结果发现三七中5种微量元素的平均含量分别为1375.84,108.31,1213.62, 0.16,21.99mg/kg,表现出Al > Fe > Mn > Zn > Se的高低顺序,HQ值大小顺序为Fe > Al > Mn > Zn > Se. HQ值均小于1,提示针对各元素,一般消费者不存在非致癌健康风险.然而,Fe,Al,Mn的日摄入量分别为0.09573,0.10759,0.00832mg/(kg·d),超出了来源于药物的微量元素的经口允许摄入量,应该加以控制.对危害指数(HI)的概率推定结果显示,5.19%的三七服用者对这5种微量元素的暴露具有非致癌健康风险.  相似文献   

12.
A gas chromatographic method without derivatization was developed for the residue analysis of 10 organonitrogen and 9 organophosphorus pesticides in soil and water. The samples were blended or shaken with acetone for extraction. The extracts were cleaned up by coagulation, then, re-extracted with three 50 ml portions of dichloromethane. The final residue was detected by gas chromatography equipped with NPD. All of the 19 pesticides were completely separated at a constant temperature. The method described above was applicable to the simultaneous determination of 10 organonitrogen and 9 organophosphorus pesticides .in soil and water with the satisfactory recovery (from 82.42% to 103.57%), coefficient of variance (from 0.17% to 12.57%) and limit of detection (from 0.0006 ppm to 0.058 ppm).  相似文献   

13.
煤及其燃烧产物中有害痕量元素的淋滤特性研究   总被引:3,自引:0,他引:3  
通过对我国西北部上湾与石嘴山电厂原煤、底灰和飞灰中As、Pb、Cd、Mop、Mo、Co和U等有害痕量元素在不同条件下的淋滤实验,采用原子荧光光谱(AFS)和电感耦合等离子体质谱法(ICP-MS)测定了痕量元素在2套(6个)样品、3种淋滤介质、4个不同时间段获取的淋滤液中的浓度,对比不同元素间淋出率、60h的最大淋出率和淋滤强度的差异性,分析痕量元素在不同条件下的淋滤特性;通过对比元素在原煤和燃煤产物中的含量、60h的最大淋出率以及淋滤液中元素的浓度,参考相关地下水的环境质量标准对痕量元素的环境效应进行了综合评价:As与Se的淋滤性较差,淋滤液中的最大浓度较低,对环境造成危害的可能性很小;Pb与Cd在淋滤液中的最大浓度较高,可能对环境造成危害.Mo与Co的淋出性好,淋出率高,同时淋滤液中的最大浓度是三类地下水环境质量标准的5~10倍,对环境造成危害的可能性最大.  相似文献   

14.
洋河水库流域土壤与库区沉积物中磷形态特征研究   总被引:9,自引:3,他引:6       下载免费PDF全文
应用SMT法研究了洋河水库流域土壤、河道及库区沉积物中总磷(TP)、无机磷(IP)、有机磷(OP)、铁/铝磷(Fe/Al-P)、钙磷(Ca-P)等5种形态,分析了不同区域各形态磷的分布特征.结果表明,洋河水库流域土壤、沉积物中TP、总氮(TN)和有机质(OM)的均值含量总体变化趋势为河道>库区>土壤,其中TP含量变化不大,这说明营养盐不仅通过土壤径流、河道迁移进入库区,而且库区沉积物的释放作用同样明显.库区柱状沉积物有明显的“表层富积”现象,随着沉积物深度的增加,TP、TN和OM含量逐渐减少,在0~16cm下降趋势明显,16cm以下基本保持不变,说明库区沉积物主要以表层污染为主.土壤、沉积物中的磷以IP为主,大约占TP的46%~79%之间,且研究区各磷形态中以Ca-P为主,大约占TP的22%~68%,这与库区地质—地球化学特征有关.土壤中TP的增加主要来自于Ca-P,与该地区土壤的地质背景有关,河道沉积物中TP的增加主要来自于Fe/Al-P,即河道受到人类活动污染的影响较大,而库区TP的增加主要来自于OP,说明洋河水库的富营养化与流域的工业、生活污染以及农业面源污染有关.  相似文献   

15.
北京大气降尘中微量元素的空间变异   总被引:1,自引:0,他引:1  
在北京市六环内均匀布点采集了城市核心区、城市扩展区、近郊区的大气降尘.对降尘中14种稀土元素(Y、Pm除外)以及Cr、Co、Mo、Cd、Pb等5种重金属元素的化学特征进行统计分析,并结合判别分析和Spearman相关分析方法阐释了影响各区域空间变异的主要元素.最后利用三角图解法揭示空间差异的成因.结果表明,各元素含量在空间上具有明显的阶梯变化,Cr、Mo、Cd、Pb含量沿城市核心区向近郊区方向呈递减趋势,Co与14种稀土元素含量的梯度变化特征则恰好相反,由市中心向外围郊区呈递增趋势.轻稀土富集程度表现为城市核心区>城市扩展区>近郊区,Eu亏损程度相反.Mo、Co、Pb元素可用来表征区域降尘的空间差异(68.2%).LaCeSm三角图解表明北京降尘主要来源于壳源物质.PbCoMo和CrCoMo三角图解可以很好地解释不同污染源贡献程度的差别是造成降尘中微量元素在空间尺度上的差异的原因.近郊区降尘受到土壤扬尘、燃煤的影响较大.城市核心区降尘主要受到交通排放的影响.城市扩展区处于过渡带,降尘受到交通、燃煤、土壤扬尘等的影响作用居中.  相似文献   

16.
In greenhouse miniplots with soil moisture moving upward from the subsoil, toxicants of carbofuran moved upward and became detectable at the soil surface in ca. 3, 7, and 28 days after 10% granules of the insecticide were banded 1, 3, and 10 cm, respectively, below the surface. The test soil had a pH of 5.2 and contained 2.9% organic matter. Toxic residues reaching the soil surface from a depth of 5–10 cm increased over a period of 8–12 months and gradually decreased thereafter. Fifteen to 20 ppm in the surface soil was highly toxic to flies contacting the soil surface. Amounts in excess of 40 ppm in the surface layer caused knockdown in 10–15 and estimated death in less than 30 s. The LD50 for cabbage maggot eggs on the surface of treated soil was 8.2 ppm and for larvae 0.86 ppm. Chemical analysis records correlated well with those of bio-assay tests. In field microplots, the addition of water during rainstorms (giving a total of 50 mm) demonstrated that toxic residues of carbofuran could be leached downward to at least 45 cm. However, under the normal weather conditions of 1980 and under abnormally dry conditions most of the detectable residues remained near or above the point of application.  相似文献   

17.
肖怡  李峥  黄容  汤奥涵  李冰  王昌全 《环境科学》2022,43(7):3884-3894
以成都平原典型稻麦轮作长期定位施肥试验土壤为研究对象,设置常规施肥(T1)、猪粪替代50%氮肥(T2)和猪粪替代50%氮肥+秸秆全量还田(T3)这3种处理,采用Biolog-ECO方法,研究长期有机物料还田下土壤和土壤可溶性有机质(DOM)的碳源代谢能力.结果表明,T3处理较T1和T2处理显著增加了土壤的碳源代谢能力,平均颜色变化率(AWCD)分别增长16%和48%;同时T3处理提高了土壤DOM的碳源代谢能力,其AWCD值为0.43.从微生物碳代谢功能多样性指数来看,土壤和土壤DOM中微生物的碳代谢功能多样性指数均以T3处理最高,其中土壤DOM中微生物的Shannon、 Simpson和McIntosh指数分别为2.73、 0.91和3.75.主成分分析和富集分析结果显示,不同施肥处理下土壤和土壤DOM的主要利用碳源类型存在差异,对于DOM而言,T1和T2处理的DOM主要利用碳源仅为糖类,而T3处理增加了对氨基酸类、羧酸类、聚合物类和胺类的利用.土壤pH和质地的改变是引起土壤DOM碳源代谢能力差异的主要因素.综上,猪粪配合秸秆施用显著增加了土壤和土壤DOM的微生物群落多样性和碳源代谢能...  相似文献   

18.
Stabilized sewage sludge (SS) by fly ash (FA) and alkaline mine tailing as artificial soil, to be applied on the ecological rehabilitation at mining junkyards, offers a potentially viable utilization of the industrial by-product, as well as solves the shortage of soil resource in the mine area. An incubation experiment with different ratios of SS and FA was conducted to evaluate the solubility of ions and trace elements from stabilized sewage sludge. Results showed that fly ash offset a decrease in pH value of sewage sludge. The pH of (C) treatment (FA:SS = 1:1) was stable and tended to neutrality. The SO4^2- and Cl^- concentrations of the solution in the mixture were significantly decreased in the stabilized sewage sludge by alkaline fly ash and mine tailing, compared to the single SS treatment. Stabilized sewage sludge by FA weakened the nitrification of total nitrogen from SS when the proportion of FA in the mixture was more than 50%. The Cr, Ni, and Cu concentrations in the solution were gradually decreased and achieved a stable level after 22 days, for all treatments over the duration of the incubation. Moreover stabilized sewage sludge by fly ash and/or mine tailing notably decreased the trace metal solubility. The final Cr, Cu, and Ni concentrations in the solution for all mixtures of treatments were lower than 2.5, 15, and 50 μg/L, respectively.  相似文献   

19.
IntroductionZnbelongstothegroupoftracemetalspotentiallymosthazardoustothebiosphere.TogetherwithCuandNi,zincisphytotoxic ,sotheconcernaboutthismetalismainlydirectedateffectsoncropyieldandsoilfertility(Kiekens,1 990 ) .ThemainpollutantsourcesforZnissoilsareme…  相似文献   

20.
Field investigations were conducted to measure subsoil trace element content and factors influencing content in an intensive periurban market garden in Chenggong County,Yunnan Province,South-West China.The area was divided into three different geomorphological units:specifically,mountain (M),transition (T) and lacustrine (L).Mean trace element content in subsoil were determined for Pb (58.2 mg/kg),Cd (0.89 mg/kg),Cu (129.2 mg/kg),and Zn (97.0 mg/kg).Strong significant relationships between trace element con...  相似文献   

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