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1.
大洋磷酸盐化作用对富钴结壳元素富集的影响   总被引:23,自引:2,他引:23  
中国首次对与大洋富钴结壳密切相关的磷酸盐化作用进行了研究。对取自西太平洋麦哲伦海山区一厚度为 10cm的富钴结壳样品 ,自顶至底以 5mm间距采取了 2 0个分层样品进行了成矿元素和稀土元素分析。结果表明 ,未被磷酸盐化的新结壳和磷酸盐化的老结壳间主要成矿元素的含量相差显著。老结壳中Fe、Mn、Si、Al、Zn、Mg、Co、Ni、Cu元素亏损 ,亏损次序为Co >Ni>Mg >Al>Mn >Si>Cu >Zn >Fe;而Ca、P、Sr、Ba、Pb元素含量增加 ,富集次序为P >Ca >Ba >Pb >Sr。研究认为 ,结壳中磷酸盐化作用的强弱制约着富钴结壳成矿元素含量的变化 ,磷酸盐化作用是造成老结壳中主要成矿元素Co、Ni等贫化流失的根本原因。研究还表明 ,磷酸盐化作用对富钴结壳的稀土元素丰度也产生一定影响 ,使老结壳的稀土总量和Ce含量高于新结壳 ,但未显著改变其稀土配分模式和分馏特征。研究证实 ,老结壳的Y正异常与磷酸盐化作用无关。磷酸盐化作用的研究为富钴结壳矿产资源的评价和综合利用提供了有用信息。  相似文献   

2.
太平洋北部铁锰结核富集区沉积物的元素地球化学特征   总被引:2,自引:1,他引:2  
鲍根德 《沉积学报》1990,8(1):44-56
本文对太平洋北部铁锰结核富集区沉积物的元素地球化学作了较为详细的研究。因子分析提供的信息表明,元素的分布主要受三个因子控制:(1)粘土及Fe、Mn氧化物水化物胶体的吸附作用;(2)生物化学作用过程有关的自生沉积作用;(3)海底页岩风化及附近海区的火山喷发作用。元素的来源:(1)Fe、Mn、Cu、Co、Ni、Zn、Cr、Cr、Mg、Al、Ti、K共生,主要来自粘土吸附;(2)C有机、N、Sr、Na及Si、Ca、Sr主要来自生物化学过程沉积;(3)Pb主要来源于岩石碎屑(火山喷发碎屑)。  相似文献   

3.
Doklady Earth Sciences - Published data and research results from the authors on the concentrations of dissolved trace elements (P, Si, Li, Rb, Cs, Sr, Ba, Mn, Fe, Co, Ni, Cu, Zn, Cd, Tl, Pb, Al,...  相似文献   

4.
The specific chemical and mineral composition of discoid, cake-shaped, and platy ferromanganese nodules (FMNs) from the Chukchi Sea are considered. The main ore components of these FMNs are Fe, Mn, and P. The contents of trace elements (except for Ba and Sr) do not exceed hundredths of percent. Maximum concentrations of most of these elements are specific for the cake-shaped nodules. In general, Mn accumulates most intensely in FMNs. Next (in order of decrease) are Ag(?), Co, and Pb; Sr, Fe, P, Y, and Ca; and Ni, La, Zn, and Cu. As for Ba, Cr, Mg, and K, they do not accumulate in the FMNs. “Dilution” is typical of Si, Al, Na, and Ti. The main ore phases are strengite and amorphous Mn hydroxides. It has been revealed for the first time for the Chukchi Sea that Cu, Zn, Sn, Ni, Pb, W, Bi, Cr, Fe, Ti, Ag, Au, Y, Zr, and La–Nd lanthanides form individual mineral microphases in FMNs: native elements, intermetallic compounds, oxides, and, much more seldom, tungstates, silicates, and phosphates. Accessory ore mineralization is the best pronounced and most diverse in the platy nodules. Though the FMNs from the Chukchi Sea are diagenetic, high-temperature fluids are, most likely, the source of microinclusions of various accessory ore minerals.  相似文献   

5.
北山地区植被属戈壁荒漠植被类型,主要植物群落为红沙,红沙中多数元素特别是成矿元素及其伴生元素的含量和变化系数矿区大于背景区,元素含量背景区呈对数正态分布,矿区呈偏对数正态或多峰分布,红沙中的元素组合分类背景区为Au,Cu,Pb,Zn,As,Sb,Mo,V,Mn和Ag,Sn,Sr,Ba及Ti,Cr,Co,Ni,金矿区为Au,Ag,As,Sb,Mo,Mn,Sr和Cu,Pb,Zn,Sn,Ba及Co,Ni,Ti,V,Cr,铜矿区为Cu,Pb,Zn,Mo,Au,Ag,Ba和As,Sb,Sn,Mn及Ti,V,Cr,Co,Ni,Sr,矿区红沙中浓集系数较大的元素多数在矿区岩石中的浓集系统亦较大,金,铜矿床红沙和岩石中的特征元素分别都有Au,Ag,Ag,Sb,Mo,(Mn)和Cu,Pb,(Ba,Ti,Cr)。在金,铜矿床(体上方分别发育有良好的Au和Cu的生物地球化学异常和元素组合及分带,根据红沙的地球化学特征能,判断金或铜矿种类型,并能对掩埋,隐伏金,铜矿床(体)进行定位预测。  相似文献   

6.
Fourteen ferromanganese nodule–sediment pairs from different sedimentary environments such as siliceous ooze (11), calcareous ooze (two) and red clay (one) from Central Indian Ocean Basin (CIOB) were analysed for major, trace and rare earth elements (REE) to understand the possible elemental relationship between them. Nodules from siliceous and calcareous ooze are diagenetic to early diagenetic whereas, nodule from red clay is of hydrogenetic origin. Si, Al and Ba are enriched in the sediments compared to associated nodules; K and Na are almost in the similar range in nodule–sediment pairs and Mn, Fe, Ti, Mg, P, Ni, Cu, Mo, Zn, Co, Pb, Sr, V, Y, Li and REEs are all enriched in nodules compared to associated sediments (siliceous and calcareous). Major portion of Si, Al and K in both nodules and sediments appear to be of terrigenous nature. The elements which are highly enriched in the nodules compared to associated sediments from both siliceous and calcareous ooze are Mo – (307, 273), Ni – (71, 125), Mn – (64, 87), Cu – (43, 80), Co – (23, 75), Pb – (15, 24), Zn – (9, 11) and V – (8, 19) respectively. These high enrichment ratios of elements could be due to effective diagenetic supply of metals from the underlying sediment to the nodule. Enrichment ratios of transition metals and REEs in the nodule to sediment are higher in CIOB compared to Pacific and Atlantic Ocean. Nodule from red clay, exhibit very small enrichment ratio of four with Mn and Ce while, Al, Fe, Ti, Ca, Na, K, Mg, P, Zn, Co, V, Y and REE are all enriched in red clay compared to associated nodule. This is probably due to presence of abundant smectite, fish teeth, micronodules and phillipsite in the red clay. The strong positive correlation (r ? 0.8) of Mn with Ni, Cu, Zn and Mo and a convex pattern of shale-normalized REE pattern with positive Ce-anomaly of siliceous ooze could be due to presence of abundant manganese micronodules. None of the major trace and REE exhibits any type of inter-elemental relationship between nodule and sediment pairs. Therefore, it may not be appropriate to correlate elemental behaviour between these pairs.  相似文献   

7.
利用矿质元素的测定数据判别茶叶的产地和品种   总被引:23,自引:0,他引:23  
应用微渡消解处理样品,电感耦舍等离子体质谱法测定,考察了不同产地、不同种类的29种茶叶中的Mg、Al、P、Ca、Cr、Mn、Fe、Co、Ni、Cu、Zn、Sr和Ph共13种元素的含量。原始数据经过标准化处理后,结合聚类分析和主成分分析,对来自江西、云南、广东和福建四个地区的茶叶进行了产地判别。对不同种类的茶叶(红茶、绿茶、鸟龙茶、黑茶)也进行了区分,结果令人满意。茶叶中矿质元素的含量可做为茶叶产地判别的测量指标之一。  相似文献   

8.
沉积物的元素地球化学特征是对沉积盆地水体环境以及古气候条件变化的响应。本文根据元素(Al、Fe、Mg、Ca、K、Na、P、V、Ni、Co、Cr、Cu、Zn、Sr、Ba、Cd、Li、Mn、Pb、Ti)的含量及其比值(Al/Ti、Fe/Mn、Sr/Ba、Mg/Ca、Sr/Ca、Na/Ca、V/Cr、Ni/Co、Ni/V)的变化,对三水盆地古近系心组红岗段生油层的沉积条件进行了系统分析。心组红岗段下部(亚段A)表现为较稳定的地球化学特征。各元素丰度及其比值指示这一时期陆源输入持续较高、且物源组成变化不大。由于海水入侵的影响,湖盆水体盐度相对较高,底部水体以弱氧化条件为主,O2-H2S界面位于水/沉积物界面附近。红岗段中上部(亚段B、C)的元素地球化学特征变化较为频繁且幅度很大,反映古气候和湖盆沉积条件的迅速变迁。在潮湿气候条件下,沉积物的地球化学特征表现为以Al、Ti为代表的外源元素含量及其比值较高,而Mg、Ca等盆内化学沉积元素含量较低。古氧气指标指示底部水体为还原环境,有利于有机质保存。因而,相应于较高的有机碳含量。在间歇性干旱时期,陆源输入减少,外源元素含量及其比值显著降低。随着蒸发作用的加强,水体盐度加大,内源元素丰度以及Mg/Ca、Sr/Ba、Sr/Ca和Na/Ca比值大幅度上升。底部水体为氧化环境,O2-H2S界面多位于水/沉积物界面或沉积物中。上述两种气候条件在红岗段中上部沉积时期交替出现。红岗段沉积后期由于淡水的长期输入,湖水出现逐渐淡化趋势。  相似文献   

9.
Four overbank profiles from the three terraces of different age were sampled in 10 to 20 cm intervals for the bulk content of major and minor (Ca, Mg, Fe, Ti, Al, Na, K and P) and trace (Mo, Cu, Pb, Zn, Ni, Co, Mn, As, U, Th, Sr, Cd, Sb, V, La, Cr, Ba, W, Zr, Ce, Sn, Y, Nb, Ta, Sc, Li, Rb and Hf) elements in the minus 0.125 mm fraction. Univariate statistics together with analysis of variance discriminated between the lower-lying carbonate (CA) population dominantly composed of carbonates and the overlying silicate (SI) population being dominantly of silicate mineralogy. This stratified pattern resulted from the intensive erosive action of melting glaciers exerted on limestones and dolomites in the alpine region, followed by local inputs mainly of silicate composition. Elements exhibiting the greatest between-population variability are Ca and Mg being enriched in the CA population and Fe, Mn, P, Sr, Al, Na, K, Li, Rb, Y, Zr, Ni, Cr and Ti being enriched in the SI population. Anomalously high Hg, Pb and Ba concentrations (maximum values: 6,500±2,860 ppb, 225±13 ppm and 1,519±91 ppm, respectively) in the lowermost part of the profile S7, which is nearest to the Croatian-Slovenian border, derive from the mineralized Slovenian catchment area. This profile also contains trimodal frequency distributions of Fe, Mn and P whose highest concentrations coincide with increased values of Zn and Cu which are bimodally distributed. Geochemical patterns of majority of elements in all four profiles consistently reflect the average compositions of the upstream drainage basins.  相似文献   

10.
Phytoplankton samples, collected in Monterey Bay, California, were analyzed for their Pb, Hg, Cd, Co, Ag, Cr, Ti, V, Mn, Ni, Cu, Fe, Zn, AI, Mo, Ba, Sr, K, Ca, Mg, Na and SiO2 content. The results of these analyses were categorized on a chemical basis and the sample data were placed in three groups: Group I, Ti not detected; Group II, Ti detected; and Group III, Sr concentrators present. Levels of most elements were higher in Groups II and III for a variety of reasons that are discussed in the text. The siliceous frustules, remaining after organic-matter digestion, were also analyzed for the elements listed above. Significant amounts of Al, Ti, Fe, Mn, Cu and Zn were found.Zooplankton and microplankton samples, collected in Monterey Bay, California; off the coast of Oregon; and on a transect between Hawaii and Monterey, were also analyzed for the elements listed above (except Si). In general, element levels in the inshore and offshore zoo-plankton were similar; however, the microplankton samples, in which strontium was highly concentrated, were almost always higher in Pb, Hg, Cu, Fe and Zn.  相似文献   

11.
The Pliocene aquifer receives inflow of Miocene and Pleistocene aquifer waters in Wadi El Natrun depression. The aquifer also receives inflow from the agricultural activity and septic tanks. Nine sediment samples were collected from the Pliocene aquifer in Wadi E1 Natrun. Heavy metal (Cu, Sr, Zn, Mn, Fe, Al, Ba, Cr, Ni, V, Cd, Co, Mo, and Pb) concentrations of Pliocene aquifer sediments were investigated in bulk, sand, and mud fractions. The determination of extractable trace metals (Cu, Zn, Fe, Mn, and Pb) in Pliocene aquifer sediments using sequential extraction procedure (four steps) has been performed in order to study environmental pathways (e.g., mobility of metals, bounding states). These employ a series of successively stronger chemical leaching reagents which nominally target the different compositional fractions. By analyzing the liquid leachates and the residual solid components, it is possible to determine not only the type and concentration of metals retained in each phase but also their potential ecological significance. Cu, Sr, Zn, Mn, Fe, and Al concentrations are higher in finer sediments than in coarser sediments, while Ba, Cr, Ni, V, Cd, Co, Mo, and Pb are enriched in the coarser fraction. The differences in relative concentrations are attributed to intense anthropogenic inputs from different sources. Heavy metal concentrations are higher than global average concentrations in sandstone, USEPA guidelines, and other local and international aquifer sediments. The order of trace elements in the bulk Pliocene aquifer sediments, from high to low concentrations, is Fe?>?Al?>?Mn?>?Cr?>?Zn?>?Cu?>?Ni?>?V?>?Sr?>?Ba?>?Pb?>?Mo?>?Cd?>?Co. The Pliocene aquifer sediments are highly contaminated for most toxic metals, except Pb and Co which have moderate contamination. The active soluble (F0) and exchangeable (F1) phases are represented by high concentrations of Cu, Zn, Fe, and Mn and relatively higher concentrations of Pb and Cd. This may be due to the increase of silt and clay fractions (mud) in sediments, which act as an adsorbent, retaining metals through ion exchange and other processes. The order of mobility of heavy metals in this phase is found to be Pb?>?Cd?>?Zn?>?Cu?>?Fe?>?Mn. The values of the active phase of most heavy metals are relatively high, indicating that Pliocene sediments are potentially a major sink for heavy metals characterized by high mobility and bioavailability. Fe–Mn oxyhydroxide phase is the most important fraction among labile fractions and represents 22% for Cd, 20% for Fe, 11% for Zn, 8% for Cu, 5% for Pb, and 3% for Mn. The organic matter-bound fraction contains 80% of Mn, 72% of Cu, 68% of Zn, 60% of Fe, 35% of Pb, and 30% of Cd (as mean). Summarizing the sequential extraction, a very good immobilization of the heavy metals by the organic matter-bound fraction is followed by the carbonate-exchangeable-bound fraction. The mobility of the Cd metal in the active and Fe–Mn oxyhydroxide phases is the highest, while the Mn metal had the lowest mobility.  相似文献   

12.
The water quality of the Vacacaí River was assessed at different sites in the period between winter 2005 and autumn 2006. All samples were analyzed for 52 elements (Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, Li, Be, Mg, Al, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, Ga, As, Se, Rb, Sr, Ag, Cd, In, Cs, Ba, Tl, Pb, Bi, U, Na, K, Hg, B, Mo, Sn, Te, Ti), temperature, pH, ammonia, and alkalinity levels. Water from the Vacacaí River ranged from slightly acidic to alkaline. No difference was observed in the chemical composition at different sites of the Vacacaí River. Levels of Ba, Ca, Sr and Mg increase in the dry seasons and reach their highest concentrations in autumn; Be and U decrease in the dry season and reach their highest concentration in spring. Al, Fe, Cr, Ni, Th, U Mn, Ca and Mg are highly positively related, indicating a common origin. Se and Cu are probably from anthropogenic source, from the rice crops of the margins of the river. Waterborne Al and Fe levels were above the desirable level for drinking water at all sites during all seasons. These results demonstrate the need for constant monitoring of water parameters, which is crucial to ensure water quality for the population of this region.  相似文献   

13.
作物产量与土壤环境的关系   总被引:11,自引:1,他引:10  
曾昭华 《湖南地质》2000,19(1):25-29
作物的产量与土壤元素中N、P、K、Na、Ca、Mg、S、Fe、Mn、Cu、Zn、B、Mo、V、Co、Ni、Cr、Pb、Cd、Hg、Se、F、TI、Ba、Te、Ta、Sr、Ti、Si等元素及稀土、有机质、酸碱度和含水量、含盐量密切有关。  相似文献   

14.
Concentrations of some heavy metals and trace elements such as Cr,Ga,Ni,Zn,Mo,Cu, Pb,Yb,Y,Nb,Ti,Sr,Ba,Mn,Sc,Co,V,Zr,Fe,Al,W,Se,Bi,Sb,As,Cd in recent mollusk shells and factors affecting their distribution and deposits collected from various depths in the southern and southwestern parts of the Marmara Sea are investigated.The distribution of the elements in the shells is categorized into four groups.Of these,concentrations of 12 elements(As,Bi,Cd,Co,Ga,Mo,Nb, Sb,Se,Sc,W and Yb)are below zero [(0.053-0.79)×10~(-6)];concentrations of seven elements(Cr,Ni, Pb,V,Y,Zr and Cu)are(1.0-6.0)×10~(-6);concentrations of four elements(Ti,Mn,Ba and Zn)are 10- 20×10~(-6);and concentrations of five elements(Si,Al,Fe,Mg and Sr)are(47.44-268.11)×10~(-6).The taxonomic characteristics of the 29 elements were studied separately in mollusk shells such as Chamalea gallina(Linné),Pitar-rudis(Poll),Nassarius reticulatus(Linné),Venerupis senescens (Coocconi),Mytilus galloprovincialis(Lamarck),Mytilaster lineatus(Gemelin in Linné)and Chlamys glabra.It was found that,in mollusk taxonomy,the elements have unique values.In other words, element concentrations in various mollusk shells depend mainly on the taxonomic characteristics of mollusks.In various bionomic environments different element distributions of the same species are attributed to the different geochemical characters of the each environment.Data obtained in this study indicate that the organisms are the most active and deterministic factors of the environment.  相似文献   

15.
电感耦合等离子体发射光谱法测定工业硅中微量元素   总被引:11,自引:4,他引:7  
沙艳梅 《岩矿测试》2009,28(1):72-74
采用电感耦合等离子体发射光谱法同时测定工业硅中可能存在的铝、铁、钙、镁、钾、钠、磷、钡、铍、镉、铈、钴、铬、铜、锂、锰、钼、镍、铅、钛、钒、钨、锌、砷、锶、铼、锑、硼28个微量元素,并以差减法计算基体硅的含量,实现了对试样基体及杂质元素含量的同时测定。方法对28个微量元素的回收率为94.0%~103.4%,精密度(RSD,n=10)低于3.0%。方法经国家实物标准物质验证,测定值与标准值基本相符。  相似文献   

16.
Based on 225 analyses of quartzites, siliceous granoblastites,calc silicate rocks, calcite and dolomite marbles, including120 analyses of pelites and semipelites, sedimentary trendsof chemical variation are identified in staurolite and sillimanitegrade rocks. The correlation of original clay mineral contentwith Ti, Fe, K, Rb, Y, Nb, Ca, Ni, Ga, Zn and probably Ba andMn is shown. A similar clay mineral (whose composition is calculated)was added to all the sediments except the quartz-rich sandstones,now quartzites. This pattern appears to be general for mostsediments, based on crustal averages. The form of the originaladdition of Sr in the sediments might be identified as eithercarbonate or feldspar by a Ca vs. Sr plot. The southern pelites in a 2–4 km peripheral zone to theConnemara orthogneisses and migmatites have been metasomatized.The crude order of elemental enrichment from the elements increasedthe most to those increased the least relative to the same stratigraphicalhorizons in the north is: Mn, Ba, Th, Cu, Ca, Sr, Y, Pb, Zn,Pr, Ge, Nd, La, Mg, S, Ce, Rb, Sm, Ti, Na, K and Ga while Si,Al, Cr, Ni, Co, Fe and P are unchanged or removed. The sourceof the material added is postulated to be the water-rich residualfraction of the migmatitic quartz diorite gneiss, the transportbeing by movement of a water-rich fluid out of the migmatites,the fixation being mainly in biotite and new, more calcic, plagioclaseporphyroblasts, there being a positive correlation between elementenrichment and ionic radius.  相似文献   

17.
Selenium and heavy metals content in some Mediterranean soils   总被引:1,自引:0,他引:1  
The study of metal contents in industrial, agricultural or/and polluted soils compared with natural or unpolluted soils is currently necessary to obtain reference values and to assess soil contamination. Nonetheless, very few works published appear in international journals on elements like Se, Li and Sr in Spanish soils. This study determines the total levels of Se, Li, Sr, As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, Fe, Mn and Ba in 14 natural (unpolluted) soils (Gypsisols, Leptosols, Arenosols and Acrisols), 14 agricultural soils (Anthrosols, Fluvisols and Luvisols), and 4 industrial–urban affected-surface soil horizons (Anthrosols and Fluvisols) of Eastern Spain. The geochemical baseline concentrations (GBC) and reference values (RV) have been established, and the relationships among elements and also between soil properties and elemental concentrations have been analysed. The RV obtained in this study were (mg kg−1): Se 2.68, Li 115, Sr 298, Cd 0.97, Co 35, Cr 217, Cu 46, Ni 50, Pb 137, V 120, Zn 246, Fe 124,472, Mn 2691, and Ba 743. The RV for Se and Li were used as a preliminary approach to assess soil contamination in Spanish soils. The results confirm human impact on Sr, As, Cd, Cr, Cu, Ni, Pb and Zn soil concentrations, but evidence no deviation from natural Se, Li, Co, V, Fe, Mn and Ba concentrations. The results obtained from the statistical analysis reveal significant correlations between some elements and clay and soil organic matter (SOM) contents, indicating that metal concentrations are controlled by soil composition. One particularly interesting finding is the high correlation coefficients obtained between SOM and Se, Cd, Cr, V, Fe, and Mn, and between clay and Cd, Zn, V, Fe and Mn. Once again, these facts confirm the role of SOM and clay minerals in soil functions and that soil is an ecosystem element responsible for maintaining environmental quality.  相似文献   

18.
《Applied Geochemistry》2001,16(11-12):1323-1331
This paper reports the first results of a low-density geochemical survey covering the whole continental area of Portugal, taking both topsoils and active stream sediments as the sampling media. The data were obtained in a consistent way from 653 sites at a sampling density of 1 site/135 km2. The samples were analysed for 31 elements by ICP-AES and after quality control the following 19 were selected: Al, As, Ba, Ca, Co, Cr, Cu, Fe, K, La, Mg, Mn, Ni, P, Pb, Sr, Th, V and Zn. The baseline levels for these elements are presented. The first geochemical maps of Portugal were prepared and the geochemical patterns are generally well correlated to geological factors sometimes combined with anthropogenic influences. Some general trends can be observed between geochemical patterns and soils distribution.  相似文献   

19.
In order to investigate the factors influencing the distribution of 32 potentially toxic elements in the Ptolemais–Kozani basin, northwestern Greece, 38 soil samples were collected and analyzed. Concentrations of Al, Ca, Fe, K, Mg, Mn, Na, P, Ti, Ba, Co, Cr, Cu, La, Li, Ni, Pb, Sc, Sr, V, Y, and Zn were determined by ICP-AES and concentrations of As, Bi, Cd, Cs, Mo, Rb, Sb, Th, Tl, and U by ICP-MS. Bivariate analysis, principal component analysis, and geostatistical analysis were employed to investigate the factors influencing the distribution of the elements determined in the study area. The results indicate that the distribution of the majority of elements determined, especially for Cr, Ni, and associated elements, is greatly influenced by the geology and geomorphology of the study area. Principal component analysis has yielded four factors that explain over 77% of the total variance in the data. These factors are as follows: lithophilic elements that are associated with Al silicates minerals of K (factor I: 29.4%), ultramafic rocks (factor II: 20.5%), elements that are coprecipitated with Fe and Mn oxides (factor III: 18.0%), and anthropogenic activities (factor IV: 9.3%). The anthropogenic activities that influence the distribution of several potentially toxic elements (i.e., Cd, Cu, Pb, Zn) are agricultural practices and the deposition of fly ash in the vicinity of the local power stations.  相似文献   

20.
Concentrations of arsenic and its geochemically associated elements, Ag, Co, Cu and Ni, were measured together with Al, Ba, Cd, Fe, Mn, Pb, Sr and Zn in aquatic bryophytes. These bryophytes originated from some of the arsenic mineralization zones of the Klodzko-Zloty Stok granodiorite massif and its metamorphic envelope (Sudetes Mts., Poland) and from identical zones of the east Sudetic Rychlebske Mts. and Jesenik Mts. (Czech Republic). Concentrations of As in all examined populations were higher than background values (1 μg/g dry weight) culminating in an average maximum of 6270 μg/g in Chiloscyphus pallescens from a stream draining an area with former arsenic and gold mining near Zloty Stok.This survey has shown that aquatic bryophytes accumulate the examined elements to a high degree especially if growing in areas with mineral deposits. This was demonstrated by strong positive correlations between Ba, Sr, Zn concentrations in water and Platyhypnidium rusciforme.  相似文献   

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