Concentration and distribution of elements in Late Permian coals from western Guizhou Province,China

With the aim of better understanding geochemistry of coal, 71 Late Permian whole-seam coal channel samples from western Guizhou Province, Southwest China were studied and 57 elements in them were determined. The contents of Al, Ca, Co, Cr, Cu, Fe, Ga, Hf, K, Li, Mn, Mo, Nb, Ni, Sn, Ta, Ti, Th, U, V, Zr, and REEs in the Late Permian coals from western Guizhou Province are higher than the arithmetic means for the corresponding elements in the US coals, whereas As, Ba, Br, F, Hg, P, Se, and Tl are lower. Compared to common Chinese coals, the contents of Co, Cr, Cu, Ga, Hf, Li, Mn, Mo, Ni, Sc, Sn, Ti, U, V, Zn, and Zr in western Guizhou coals are higher, and As, F, Hg, Rb, Sb, Tl, and W are lower. Five groups of elements may be classified according to their mode of occurrence in coal: The first two, Group A, Tm–Yb–Lu–Y–Er–Ho–Dy–Tb–Ce–La–Nd–Pr–Gd–Sm, and Group B, As–Sr–K–Rb–Ba–F–Ash–Si–Sn–Ga–Hf–Al–Ta–Zr–Be–Th–Na, have high positive correlation coefficients with ash yield and they show mainly inorganic affinity. Some elements from Group B, such as Ba, Be, Ga, Hf, and Th, are also characterized by significant aluminosilicate affinity. In addition, arsenic also exhibits high sulfide affinity (r_S–Fe>0.5). The elements, which have negative or lower positive correlation coefficients with ash yield (with exceptions of Bi, Cs, Nb, Mn, Se, and Ti), are grouped in other four associations: Group C, Cr–V–Mo–U–Cd–Tl; Group D, Hg–Li–Sc–Ti–Eu–Nb–Cs–W; Group E, Bi–Sb; and Group F, Co–Ni–Cu–Pb–Zn–Mg–Se–Ca–Mn–S–Fe. The correlation coefficients of some elements, including Co, Cr, Cu, Fe, Hg, Li, Mo, Ni, P, S, Sc, U, V, and Zn, with ash yield are below the statistically significant value. Only Cr and Cu are negatively correlated to ash yield (−0.07 and −0.01, respectively), showing intermediate (organic and inorganic) affinity. Manganese and Fe are characterized by carbonate affinity probably due to high content of epigenetic veined ankerite in some coals. Phosphorus has low correlation coefficients with any other elements and is not included in these six associations. There are five possible genetic types of enrichment of elements in coal from western Guizhou Province: source rock, volcanic ash, low-temperature hydrothermal fluid, groundwater, and magmatic hydrothermal inputs.     

Evaluation of elemental enrichments in surface sediments off southwestern Taiwan

Surface slices of 20 sediment cores, off southwestern Taiwan, and bed sediment of River Kaoping were measured for major and trace elements (Al, As, Ca, Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, S, Si, Ti, V, and Zn) to evaluate the geochemical processes responsible for their distribution, including elemental contamination. Major element/Al ratio and mean grain size indicate quartz-dominated, coarse grained sediments that likely derived from sedimentary rocks of Taiwan and upper crust of Yangtze Craton. Bi-plot of SiO₂ versus Fe₂O₃^T suggests the possible iron enrichment in sediments of slag dumping sites. Highest concentrations of Cr, Mn, P, S, and Zn found in sediments of dumping sites support this. Correlation analysis shows dual associations, detrital and organic carbon, for Cr, P, S, and V with the latter association typical for sediments in dumping sites. Normalization of trace elements to Al indicates high enrichment factors (>2) for As, Cd, Pb, and Zn, revealing contamination. Factor analysis extracted four geochemical associations with the principal factor accounted for 25.1% of the total variance and identifies the combined effects of dumped iron and steel slag-induced C–S–Fe relationship owing to authigenic precipitation of Fe–Mn oxyhydroxides and/or metal sulfides, and organic matter complexation of Fe, Mn, Ca, Cr, P, and V. Factors 2, 3, and 4 reveal detrital association (Ti, Al, Ni, Pb, Cu, and V), effect of sea salt (Cl, Mg, Na, and K) and anthropogenic component (As and Zn)-carbonate link, respectively, in the investigated sediments.     

Mobility of trace and potentially harmful elements in the environment from high sulfur Indian coal mines

Coal mine rejects and sulfide bearing coals are prone to acid mine drainage (AMD) formation due to aqueous weathering. These acidic effluents contain dissolved trace and potentially harmful elements (PHEs) that have considerable impact on the environment. The behavior of these elements in AMD is mainly controlled by pH. The focus of the present study is to investigate aqueous leaching of mine rejects for prediction of acid producing potential, rates of weathering, and release of PHEs in mine drainage. Mine reject (MR) and coal samples from the active mine sites of Meghalaya, India typically have high S contents (1.8–5.7% in MR and 1.7–4.7% in coals) with 75–90% of the S in organic form and enrichment of most of the PHEs in rejects. Aqueous kinetic leaching experiments on mine rejects showed high acid producing potential and release of trace and potentially harmful elements. The elements (Sb, As, Cd, Cr, Co, Cu, Pb, Mn, Ni, V and Zn) in mine sample leachates are compared with those in mine waters. The concentrations of Al, Si, P, K, Ti, Mn, Fe, Co, Ni, Cu, Zn and Pb are found to increase with leaching time and are negatively correlated with pH of the solution. The processes controlling the release of these elements are acid leaching, precipitation and adsorption. The critical loads of PHEs in water affected by AMD are calculated by comparing their concentrations with those of regulatory levels. The Enrichment Factors (EFs) and soil pollution indices (SPIs) for the elements have shown that PHEs from coal and mine reject samples are mobilized into the nearby environment and are enriched in the associated soil and sediment.     

Trace-element distribution and ore formation in vein-metasomatised peridotite at Kalskaret,near Tafjord,South Norway

The concentration profiles of the trace elements, S, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Sr, and Y have been determined across a metasomatic vein in peridotite. The introduced elements Ti, V, Sr, and Y show specific enrichment in particular silicate phases in accordance with the availability of suitable lattice sites. In contrast, the other introduced trace elements (Cu and S) behave more like the redistributed elements, Cr, Ni, Mn, and Co which do not show concentration ‘fronts’ that can be simply related to the silicate minerals. Concentration of pentlandite, chalcopyrite, and Cr-magnetite near the boundary between the enstatite and anthophyllite zones gives rise to maxima in the Ni, Cu, S, and Cr distributions, while in the chlorite zone significant concentrations of Cr and Ni occur in the chlorite itself. Control of the distribution of Ni, Cu, and Cr is ascribed to the oxidation/reduction reactions involved in the formation of pentlandite, chalcopyrite and Cr-magnetite, together with the critical role of Al in limiting chlorite formation during metasomatism.     

Accumulation and sources of heavy metals in urban topsoils: a case study from the city of Xuzhou, China

The knowledge of the variability, the anthropogenic versus natural origin and corresponding environmental risk for potentially harmful elements in urban topsoils is of importance to assess human impact. The aims of the present study were: (1) to assess the distribution of heavy metals (Sn, Li, Ga, Ba, Fe, Mn, Co, Be, Ti, Al, Hg, Cr, Sb, As, Bi, Pd, Pt, Au, Ni, Cd, Zn, Cu, Pb, Se, Mo, Sc and Ag) in urban environment; (2) to discriminate natural and anthropogenic contributions; and (3) to identify possible sources of pollution. Multivariate statistic approaches (principal component analysis and cluster analysis) were adopted for data treatment, allowing the identification of three main factors controlling the heavy metal variability in Xuzhou urban topsoils. Results demonstrate that Hg, Cr, Sb, As, Bi, Pd, Pt, Au, Ni, Cd, Br, Zn, Cu, S, Pb, Se, Mo, Sc and Ag could be inferred to be tracers of anthropogenic pollution, whereas Al, Ti, Ga, Li, V, Co, Pt, Mn and Be were interpreted to be mainly inherited from parent materials. Iron, Ba, Sn, Pd and Br were interpreted to be affected by mixed sources.     

Statistical assessment of geochemical pattern in overbank sediments of the river Sava,Croatia

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.     

Sampling, Sample Preparation and ICP-MS Chemical Analysis of Lake Baikal Sponges

Procedures for sampling, sample preparation and ICP-MS analysis of endemic sponges from Lake Baikal have been developed. Sample decomposition was carried out using an open acid decomposition with ultrasound treatment. The distribution of nineteen elements (Mg, Al, P, Ca, Ti, Mn, Co, Ni, Cu, Rb, Sr, Y, Cd, Ba, La, Ce, Pb, Th and U) in different parts of a sponge's body (outer and inner layers and layers adjacent to the substratum) was studied. Detection limits were determined; these ranged from 0.013 to 4.12 μg g^-1 for trace elements and from 23 to 130 μg g^-1 for biogenic elements. The degree of elemental uptake by living substances is discussed with regard to the environment.     

太平洋北部铁锰结核富集区沉积物的元素地球化学特征

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）。     

Microscopic morphology and elemental composition of size distributed atmospheric particulate matter in Urumqi, China

Microscopic morphology and elemental composition of atmospheric particulate matter (PM) in 13 different size fractions from 0.01 to 10 μm were studied using a Field Emission Scanning Electron Microscope with Energy-Dispersive Spectrometer (FESEM–EDX). The relative mass fractions exhibited a bimodal distribution with a major mode in the fine range (0.18–1 μm) and a minor mode in the coarse range (>1 μm), suggesting that the major pollution of PM is fine particles in this area of Urumqi atmosphere. The PM could be classified as follows: aluminosilicate/silica mineral, Si–Al rich fly ash, Fe oxide particle, Ti dominant particle, sulfate/carbonate crystal, carbonaceous aerosols (including soot, organic carbon, tar ball and irregularly shaped carbon). The soot and organic carbon with anthropogenic sources are dominant types in fine range samples (<1 μm). The natural source minerals and secondary synthesized sulfate/carbonate crystals were accumulated in the coarse range (>1 μm). Elemental composition of various types of particles (0.056–5.6 μm) was also analyzed by EDX. C, S, O, N, Si, Al, Fe, Ca, Na, K, Mg, Cl, F, Hg were detected in most samples. Si, Al and Ca accumulated in coarse fractions, while S and Hg mainly accumulated in fine fractions. Concentrations of 15 metallic elements in size range from 0.1 μm to 5.6 μm were divided into three groups based on their possible sources. (1) The crustal elements (Al, Mg, Fe, Mn and V), mainly present in coarse particles (>1 μm); and (2) the anthropogenic source elements (Ca, Ni, As, Cu, Pb, Cd and Hg). The concentrations of Ca and Ni increased with increasing particle size, while As, Cu, Pb, Cd and Hg showed opposite trends. As, Cu, Pb, Cd and Hg accumulated mainly in fine fraction (<1 μm). (3) The multi sources elements (Cr, Co and Se) possibly come from both natural and anthropogenic sources. High levels of heavy metals, especially Hg in nanosize particles, may pose great risk to human health.     

Spatial trends and losses of major and trace elements in agricultural acid sulphate soils distributed in the artificially drained Rintala area,W. Finland

Acid sulphate soils, common in the coastal areas of Finland, contribute strongly to high acid, S and metal loadings on adjacent surface waters. This, in turn, is causing significant harm to the aquatic ecology. There is, however, limited knowledge on the total amounts of acidity and chemical elements leached from these soils. The overall objective of this study was to determine geochemical patterns in acid sulphate soils and their parent sediments and, based on the identified patterns assess the extent, mechanisms and present state of leaching of major and trace elements from these soils. The distribution of pH, aqua regia extractable concentrations of P and metals (Al, Ba, Ca, Co, Cr, Cu, Fe, K, La, Mg, Mn, Na, Ni, Sr, Th, Ti, V, Zn) and total concentrations of S and C were determined in 30 vertical profiles collected in the 23 km² large Rintala agricultural area (mid-western Finland) underlain largely with S-rich sediments. It was found that approximately 70% of the area consists of acid sulphate soils with a minimum pH<4.0, an average depth of 1.8 m, and S concentrations in the parent sediments varying from 0.24 to 1.04%. Acid sulphate soils have not developed where the S concentrations in the sediments are ⩽0.10% or where the concentrations of organic C in the soil zones are >4%. Four different methods were used to estimate the losses of chemical elements from the acid sulphate soils: (1) the concentrations in the soil were compared with those in the parent sediments, (2) due to indicated heterogeneities in several profiles, the vertical changes of the immobile Ti was used to re-calculate element losses, (3) element depletions in the acid sulphate soils (as compared to those in the parent sediments) were compared to the corresponding depletions in the non acid sulphate soils, (4) element concentrations in drainage waters were compared with those in the parent sediments. Based on these calculations, it was assessed that the percentual leaching of the aqua regia extractable fraction (total for S) has been as follows: S (40–50%), Na (30–50%), Mn (25–35%), Sr (15–20%), Ca–Ni–Co (approximately 10%), Mg–K–Zn (5–10%), Th–La–Cu–Al–P–Ti–Fe (<5%), and Ba–Cr–V (<1%). While it was possible to quite accurately estimate the percentages and thus the amounts of elements lost, it was not possible to estimate the rate of leaching as there is no available detailed information on dates when ditching activities and thus oxidation-acidification processes started. Other calculations indicated that the mobile S reservoir is still some 15 ton/hectare, which is huge but still smaller than the losses that have occurred since the area was drained (23–28 ton/hectare).     

Distribution and immobilization of heavy metals in Pliocene aquifer sediments in Wadi El Natrun depression, Western Desert

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.     

Heavy metal contamination of soils and tea plants in the eastern Black Sea region,NE Turkey

The study area covers two geologically different regions which have intensively been carpeted by tea plants in the eastern Black Sea. The rocks exposed in the region contain considerable amount of trace metals due to Upper Cretaceous massive sulfide formations and tertiary epithermal mineralizations. Tea plants that grow in soils derived from such mineralized rocks contain different concentrations of Cu, Pb, Zn, Fe, Cd, P, Al, Na, K, and S. The content ratios of most of the analyzed elements except Al are higher in basaltic and sedimentary rocks. To describe the transfer of metals from soil to tea leaf, the Freundlich-type model (log c _plant = ac _soil + log b) is used. The metal concentrations in leaves of tea plant in the studied soils are ranked as Zn > Cu > Pb > Al > Cd > Fe. The capacity of the plant to affect the metal accumulation decreased as follows: Fe > Cd > Pb > Cu > Zn > Al. Negative correlations were found between pH and availability of Cu, Pb, Zn, Mn, and Al elements by the tea plant. Experimental applications indicated that tea plant leaves growing on soils with high metal contents show some signs of toxicity. In soils where, particularly, ammonium sulfate fertilizer is used, metal uptake by the tea plant was found to be significantly higher as a result of extremely acidic character of the soil.     

Geologic and biogeochemical role of crustose aquatic lichens in Lake Baikal

Based on materials collected in 2003–2007, data on aquatic lichens of the genus Verrucaria from the rocky littoral zone of Lake Baikal are discussed. The maximum density of their occurrence was observed at a depth of 1.5 m; 95–100% of rock fragments recovered from depths of 1.5–2.2 m are encrusted by 24–43% with the thalli of Verrucaria spp. It was found that the lichens contribute actively to the physical and physicochemical weathering of their rock substrate and prefer to reside on the rocks of granitic composition. The chemical composition of aquatic verrucaria is dominated by the same elements that are most abundant in the rocks (Ca > K > Fe > Al > Mg > P > S > Na > Mn > Sr > Ba), and, in most cases, the characteristic element ratios of the rock compositions are preserved in the composition of the thalli of Verrucaria spp. Compared with the elemental composition of the near-bottom water layer, the lichens most extensively concentrate the elements that slowly migrate in water: Gd > Sm > Pr > Nd > Al > La > Dy > Tb > Y > Lu > Ce > Yb > Be > Tm > Co > Nb > Mn > Zn. Compared with the composition of rocks, the mineral composition of the thalli of Verrucaria spp. is enriched by a factor of 100–10 in Hg > As > P > Zn > Li > S > U > Mo > Se > Cd > Ca > Tl > Sr > Pb > Be.     

X射线荧光光谱法同时测定土壤样品中碳氮等多元素

报道了采用粉末压片制样-X射线荧光光谱法测定土壤样品中C、N、S、Cl、Br、Hf、Mo、Sn、Se、Na、Mg、Al、Si、P、K、Ca、Ti、V、Cr、Mn、Fe、Co、Ni、Cu、Zn、Ga、As、Rb、Sr、Y、Zr、Nb、Ba、La、Ce、U、Th、Pb等38种元素的分析方法。着重研究了C和N的分析条件、存在问题和注意事项。所拟方法的检出限，精密度和准确度大多数满足覆盖区多目标地球化学调查样品分析质量的要求。     

Distribution of major and trace elements in La Luna Formation, Southwestern Venezuelan Basin

The La Luna Formation (Maraca section), Maracaibo Basin, was studied by means of V and Ni analysis of the bitumen, total organic carbon (TOC), total sulfur (St), major elements (Si, Al, Fe, Mg, Mn, Ca, Ti, Na, K, P), trace elements (V, Ni, Co, Cr, Cu, and Zn), and electron microprobe analysis (EPMA) of the whole rock, and St, major elements (Si, Al, Fe, Mg, Mn, Ca, Ti, Na, K, P), trace elements (V, Ni, Co, Cr, Cu, Zn, Mo, Ba, U, Th) and rare earth elements (La, Ce, Nd, Sn, Eu, Th, Yb, Lu) of the carbonate-free fraction. The results are discussed based on the organic and inorganic association of trace elements and their use as paleoenvironmental indicators of sedimentation. An association between V and organic matter is suggested by means of correlation between V and Ni vs. TOC, the use of EPMA (whole rock) and V and Ni concentrations (carbonate-free fraction), whereas Ni is found in the organic matter and the sulfide phase. Fe is present as massive and framboidal pyrite, whereas Zn precipitates into a separate phase (sphalerite), and Ni, Cu and, in some cases, Zn, can be found as sulfides associated with pyrite. Concentrations of V and Ni (bitumen), TOC, St, V, Ni, Cr, Cu and Zn (whole rock), U, Th, Mo (carbonate-free fraction) are indicative of changes in the dysoxic sedimentation conditions in the chert layers (TOC, St, V, Ni, Cu and low Zn and V/Cr <4) to euxinic anoxic conditions in the argillaceous limestone (TOC, St, V, Ni, Cu and high Zn and V/Cr >4). In the sequence corresponding to the argillaceous limestone, variations in the concentrations of TOC, St, V, Ni, Zn, Cu and Cr (whole rock) can be observed, also suggesting variable sedimentation conditions. The following is proposed: (i) sedimentation intervals under euxinic conditions associated with high contribution and/or preservation of organic matter, allowing a high concentration level of V and Ni in the organic phase and the accumulation of Cu, Zn and Ni (in a smaller proportion) in the sulfide phase; (ii) sedimentation intervals under anoxic conditions and in the presence of relatively lower H₂S, which allowed lower concentrations of V and Ni in the organic phase and higher concentrations of Cu, Zn, and Ni in the sulfide phase. Rare earth elements (REE) concentrations exhibit a marked increase in Ce, Nd, Sm, Eu, Y and Lu for the QM-3 interval, relative to Post-Archean Average Shale (PAAS). REE enrichment in shales has been related to the presence of phosphate minerals such as monazite or apatite. However, these minerals were not detected through XRD or EPMA in the whole rock or in the carbonate-free fraction. The association of REE with organic matter is suggested due to the absence of phosphate minerals, although assessment of these elements require further analysis.     

The effect of filtration on analyses of surface water samples. A study from the Salars of Coipasa and Uyuni,Bolivian Altiplano

Analyses by inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and cold vapour atomic absorption (for Hg, CVAA) of a wide range of elements in some 300 surface water samples from the Salar de Uyuni and Salar de Coipasa catchments of the Bolivian Altiplano have been undertaken. Comparison of analyses of acidified aliquots of unfiltered sample water with water filtered at 0.45 μm reveals that the following elements are not affected significantly by filtration in this high-pH environment: B, Ca, Li, Mg, K, Si, Na, Sr, S. The following elements appear to experience significantly elevated concentrations in unfiltered samples, relative to filtered: Al, (As to a minor extent), Ba, Be, Cd, Cr, Co, Cu, Fe, Pb, Mn, Hg, Ni, P, Ag, Tl, Ti, V. The effect appears to be related to the presence, and subsequent dissolution in acid preservative, of Fe-, Al-or Mn-oxyhydroxide flocs (or coatings on silicate particles) in unfiltered samples, and their retention or precipitation on filters.     

Fe–Al–organic Colloids Control of Trace Elements in Peat Soil Solutions: Results of Ultrafiltration and Dialysis

Size fractionation of ~40 major and trace elements (TE) in peat soil solutions from the Tverskaya region (Russia) has been studied using frontal filtration and ultrafiltration through a progressively decreasing pore size (5, 2.5, 0.22 μm, 100, 10, 5, and 1 kD) and in situ dialysis through 6–8 and 1 kD membranes with subsequent analysis by ICP-MS. In (ultra) filter-passed permeates and dialysates of soil solutions, Fe, Al, and organic carbon (OC) are well correlated, indicating the presence of mixed organo-mineral colloids. All major anions and silica are present in “dissolved” forms passed through 1 kD membrane. According to their behavior during filtration and dialysis and association with mineral or organic components, three groups of elements can be distinguished: (i) species that are weakly affected by size separation operations and largely (>50–80%) present in the form of dissolved inorganic species (Ca, Mg, Li, Na, K, Sr, Ba, Rb, Cs, As, Mn) with some proportion of small (1–10 kD) organic complexes (Ca, Mg, Sr, Ba), (ii) biologically essential elements (Co, Ni, Zn, Cu, Cd) mainly present in the fraction smaller than 1 kD and known to form strong organic complexes with fulvic acids, and, (iii) elements strongly associated with aluminum, iron and OC in all ultrafiltrates and dialysates with 30–50% being concentrated in large (>10 kD) colloids (Ga, Y, REEs, Pb, Cd, V, Nb, Sn, Ti, Zr, Hf, Th, U). For most trace metals, the proportion in the colloidal fraction correlates with their first hydrolysis constant. This implies a strong control of negatively charged oxygen donors present in inorganic/organic colloids on TE distribution between aqueous solution and colloid particles. It is suggested that these colloids are formed during plant uptake of Al, Fe, and TE from mineral matrix of deep soil horizons and their subsequent release in surface horizons after litter degradation and oxygenation on redox or acid/base fronts. Dissolved organic matter stabilizes Al/Fe colloids and thus enhances trace elements transport in soil solutions.     

Use of multivariate statistical analysis to determine the relationship between the magnetic properties of urban topsoil and its metal, S, and Br content

Multivariate statistical analysis has been used for detailed examination of the relationship between the magnetic properties of Xuzhou urban topsoil, for example concentration-dependent properties (mass magnetic susceptibility (χ), susceptibility of anhysteretic remanent magnetization (χ _ARM), saturation isothermal remanent magnetization (SIRM), soft remanent magnetization (SOFT), and frequency-dependent magnetic susceptibility (χ _FD)) and feature-dependent properties (S _{−100 mT} ratio, SIRM/χ ratio and F _{300 mT} ratio), and the concentrations of metals (Ti, Fe, Cr, Al, Ga, Pb, Sc, Ba, Li, Cd, Be, Co, Cu, Mn, Ni, V, Zn, Mo, Pt, Pd, Au, As, Sb, Se, Hg, Bi, Ag, and Sn), S, and Br in the soil. The results show that SIRM/χ ratios correlate best with the heavy metals (Hg, Cr, Sb, As, and Bi) which are mainly derived from coal-combustion emissions whereas χ _FD correlates best with the metals (Al, Ti, V, Be, Co, Ga, Mn, and Li) which principally originate from soil parents. Concentration-dependent magnetic properties (χ _ARM, χ, SIRM, and SOFT) correlate well with elements (Se, Pb, Cu, Zn, Fe, Ag, Sc, Ba, Mo, Br, S, Cd, Ni, etc.) which are mainly derived from road-traffic emissions. For the same chemical element, χ _ARM, SIRM, and SOFT values are frequently better correlated than χ values, and χ _ARM values are the best indicators of the concentrations of these elements associated with traffic emissions in this study area. In addition, S _{−100 mT} ratios significantly correlate positively with Se, Sc, Pb, Cu, Zn, Mo, and S whereas F _{300 mT} ratios only correlate positively with Pt and negatively with Fe. These results confirm the suitability of different magnetic properties for characterizing the concentrations of heavy metals, S, and Br in Xuzhou urban topsoil.     

Geochemical factors controlling accumulation of major and trace elements in Greenland coastal and fjord sediments

 The major (Al, Ti, Ca, Mg, Fe, Mn, Si) and trace element (Cd, Cr, Cu, Hg, Li, Ni, Pb, V, Zn) concentrations in surficial (<20 cm) sediments from fjords and open coastal waters around Greenland have been determined. Regionally, high concentrations of Fe, Ti, Mg, Cr, Cu, Ni, and V occur in some west and east coast sediments, but they appear to be natural in origin, as there is no indication of anthropogenic influence. Chemical partition indicates that most of the heavy metals are structurally bound in various silicate, oxide, and sulfide minerals. These host minerals occur more or less equally in the coarse and fine sediment fractions (material >63 μm and <63 μm) and have accumulated at the same rate as other detrital clastic material. Provenance and glaciomarine deposition are the main factors controlling the abundance and distribution of the major and trace elements. The chemical composition reflects the mineralogical differences in the provenance of glacial marine material deposited by water and ice adjacent to Greenland. The main source of the sediments enriched in Ti, Fe, Mg, Cr, Cu, Ni, and V appears to be material derived from the volcanic rocks of the Mesozoic-Tertiary Provinces of Greenland by glacial erosion. Received: 26 June 1995 · Accepted: 11 August 1995     

The geochemistry of major and selected trace elements in a forested peat bog, Kalimantan, SE Asia, and its implications for past atmospheric dust deposition

Biogeochemical processes in a forested tropical peat deposit and its record of past atmospheric dust deposition were assessed using the vertical distribution of lithophilic and plant essential elements in a dated core profile from Borneo, SE Asia. Peat formation started ∼22,120 ¹⁴C yr before present (BP), and Ca/Mg mass ratios of the solid peat and very low ash contents indicate a strongly ombrotrophic character throughout the deposit, implying that most of the inorganic fraction has been supplied exclusively by atmospheric inputs. Concentration profiles of Mn, Sr, and Ca suggest a very minor influence of chemical diagenesis in the underlying sediments. Silicon, Ca, Mg, P, S, and K show a strong and extended zone of enrichment in the top 200 cm of the profile, indicating that biological accumulation mechanisms are much more extensive than in temperate peat bogs.In the lower core sections, where the element distribution is dominated solely by past atmospheric deposition, average Al/Ti ratios are similar to the upper continental crust (UCC), whereas Fe is slightly enriched and Si is strongly depleted: this condition favors highly weathered tropical soil dust as the main inorganic mineral source. Significant correlation of Al, Fe, Si, S, Ca, and Ti with the lithophilic elements Y and Zr suggests that the distribution of these elements is controlled by sources of atmospheric mineral dust. The Ca/Mg, Ca/K, and Mg/K ratios of the collected rainwater samples are similar to the global average of continental rainwater and suggest a continental character for the site. This is supported by the similarity of the average concentration of Br, Mg, Ca, and S to that in temperate continental and maritime bogs in Switzerland and Scotland.The concentration profiles of Si, Fe, Al, and Ti show distinct peaks within the profile, implying enhanced dust deposition, reduced rates of peat accumulation, or possibly both owing to climatic changes during the Holocene. Enhanced dust deposition between ∼10,830 and 9060 ¹⁴C yr BP is tentatively interpreted as a Younger Dryas-like event with dust fluxes of ∼10.8 mg/m²/yr. The variations in Al/Ti and Fe/Ti profiles suggest that mineral dust sources have been changing constantly during the Holocene, with local sources being dominant between ∼7820 and 9500 ¹⁴C yr BP and long-range transport (derived most likely from China) being important during the late Pleistocene and early Holocene and from ∼7820 ¹⁴C yr BP to the present.