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1.
Contents and bioavailability of rare earth elements in agricultural soils in Hesse (Germany) 总被引：2，自引：0，他引：2
With increasing agricultural and industrial use of rare earth elements (REEs), input of REEs into the pedosphere has risen in parallel. Since total REE budgets for soils in Germany are mainly unknown, this pilot study investigates the concentrations of REEs in three loess soil profiles under agricultural land use in the Wetterau region, Germany. There were no significant REE applications in the past, so the presented data can be considered as background concentrations of REEs in soils. In addition to the total REE contents (aqua regia digestion), potentially plant‐available (EDTA) and at actual conditions available, mobile (NH4NO3) REEs have been determined for each horizon. Interactions between REE availability and properties of soils are explained after assessing several chemical and physical properties. The results reveal a wide range of total REE contents, ranging from 222 to 423 mg kg–1. With 10.1% of total REE amounts, the potentially plant‐available proportions of REEs are generally low. In contrast, yttrium, which showed high available proportion of 24.8%, was found to be comparable with Cd. Cerium is the most abundant REE in aqua regia digests, whereas only small amounts in the potentially plant‐available fraction were found. Thus negative cerium anomalies could be concluded concerning its potential availability. Generally, bioavailability of REE had significant correlations between clay contents and Fe and Mn oxides for the majority of REEs. Due to moderately high pH (CaCl2) in soils (average 6.6) the mobile fraction for most of the elements was not detectible. 相似文献
2.
粤西地区土壤-植物系统中稀土元素地球化学特征 总被引：8，自引：0，他引：8
在广东省西部不同地区采取土壤、植物样品，并对其中的稀土元素含量采用ICP-MS法测定，研究了稀土元素在土壤、植物叶中的地球化学特征。结果表明：土壤一植物系统的各环节间稀土元素的含量模式基本相似。不同母岩发育的土壤稀土分布有较大的差异，其中以花岗岩发育的土壤稀土含量最高。在土壤的各个剖面层中，心土层和底土层稀土含量高于表土层，轻重稀土发生分异，均有不同程度的Eu亏损，Ce表现为土壤各层位中的正异常。同一采样点的不同种属植物具有相似的稀土分配模式，在不同母岩发育土壤上生存的同一种属植物稀土分配模式不同，其稀土分布均受其所生存土壤的影响和制约，同时具有自身的生物地球化学特性。生物吸收系数表明植物对稀土元素的吸收能力的差异，稀土元素在由土壤向植物体运输迁移中发生了明显的分馏作用，重稀士相对贫乏。 相似文献
3.
稀土元素在土壤-玉米体系吸收的剂量效应关系研究 总被引：3，自引：0，他引：3
通过盆栽实验研究施加农用稀土微肥后,玉米根、茎和叶中稀土元素的含量变化.结果表明,玉米根和茎中稀土元素含量随外源稀土施入量的增加而增大,存在显著剂量效应关系.玉米根和茎中La/REE比值随外源稀土施加的浓度增大而逐渐与稀土微肥(常乐)的La/REE值趋于一致.发现随着施入稀土元素浓度的增加,玉米吸收的稀土元素逐步转为主要由外源施加稀土微肥贡献为主.随根施剂量加大,玉米根和茎吸收稀土元素的富集系数逐渐增大,说明外源稀土的生物有效性明显高于土壤本身的稀土.稀土元素在苗期的玉米叶片中不产生显著水平的富集. 相似文献
4.
C. LAVEUF S. CORNU D. BAIZE M. HARDY O. JOSIERE S. DROUIN A. BRUAND F. JUILLOT 《土壤圈》2009,19(3):292-304
The long-term redistribution of Zn in a naturally Zn-enriched soil during pedogenesis was quantified based on mass balance calculations. According to their fate, parent limestones comprised three Zn pools: bound to calcite and pyritesphalerite grains, bound to phyllosilicates and bound to goethite in the inherited phosphate nodules. Four pedological processes, i.e., carbonate dissolution, two stages of redox processes and eluviation, redistributed Zn during pedogenesis. The carbonate dissolution of limestones released Zn bound to calcite into soil solution. Due to residual enrichment, Zn concentrations in the soil are higher than those in parent limestones. Birnessite, ferrihydrite and goethite dispersed in soil horizon trapped high quantities of Zn during their formation. Afterwards, primary redox conditions induced the release of Zn and Fe into soil solution, and the subsequent individualization of Fe and Mn into Zn-rich concretions. Both processes and subsequent aging of the concretions formed induced significant exportation of Zn through the bottom water table. Secondary redox conditions promoted the weathering of Fe and Mn oxides in cements and concretions. This process caused other losses of Zn through lateral exportation in an upper water table. Concomitantly, eluviation occurred at the top of the solum. The lateral exportation of eluviated minerals through the upper water table limited illuviation. Eluviation was also responsible for Zn loss, but this Zn bound to phyllosilicates was not bioavailable. 相似文献
5.
《土壤圈》2006,16(1):82-90
Time series bioaccumulation of rare earth elements (REEs) in field-grown wheat with and without a dressing of extraneous REE fertilizer at different growth stages and fractionation of REEs during their transport in a soil-wheat system were determined. Time-dependent accumulation of extraneous REEs was found in different parts of wheat. An upward transport of extraneous REEs from roots to shoots under a soil dressing and a downward transport from leaves to roots with a foliar dressing were also observed. Moreover, fractionation of REEs occurred in the soil-wheat system. Compared to the host soil a positive Eu anomaly in the stems and grains as well as heavy REE enrichment in the grains were found. The ability of the different wheat organs to fractionate Eu from the REE series was ranked in the order of stems ≥ grains > leaves > roots. 相似文献
6.
Rossano EC Szilágyi Z Malorni A Pocsfalvi G 《Journal of agricultural and food chemistry》2007,55(2):311-317
Influence of clarification, filtration, and storage on the concentration of rare earth elements (REEs) was studied in white wines by inductively coupled plasma mass spectrometry (ICP-MS). Smooth and parallel chondrite-normalized (CN) plots were obtained for wines which have never been in contact with fining agents. Clarification and filtration generally used in white wine production were simulated in the laboratory using nontreated reference wines, and CN plots were compared before and after treatments. Clarification by bentonites yields an overall increase in REE concentrations resulting in substantially parallel CN curves well above the plots of the corresponding nontreated wines. Filtration using silicate (SiO2), on the other hand, changes the CN profile in a nonparallel manner due to a higher release of La, Ce, Pr, Nd, and Gd, more than other elements studied. Filtration with cellulose powder causes a small increase in the concentration of light REEs, while the concentrations of other elements remain basically unchanged. Storage conditions could also affect the REE pattern of wine. We found that the influence of glass is greater than that of stainless steel and wood. In addition, we report that commercially available finished white wines from the same region show highly different REE patterns depending on the winemaking practices employed. 相似文献
7.
8.
Xing-Yue Wen Cheng-Min Huang Ya Tang Suo-Lang Gong-Bo Xin-Xin Hu Zhang-Wen Wang 《Journal of Soils and Sediments》2014,14(10):1693-1702
Purpose
The geochemistry of rare earth elements (REEs) taken from the sediments of a karst lake was analyzed to track the provenance of the sediments and the history of soil erosion in the Jiuzhaigou Nature Reserve (JNR) in Sichuan Province in southwest China.Materials and methods
The REE concentrations of 177 samples including 150 lake sediments, 13 soils, 8 loess, 3 carbonate rocks, and 3 water were determined using a quadruple inductively coupled plasma mass spectrometer (Q-ICP-MS). The grain size distributions of 139 sediment samples were measured using a Malvern Master Size 2000 laser particle size analyzer. The carbonate contents of 159 sediment samples were determined using a gasometric method. The dried remains after reaction with HCl were defined as acid-insoluble residues. The mineral composition of the sediments was measured using a Philips X'Pert Pro X-ray diffractometer.Results and discussion
The lake sediments in the JNR exhibit features similar to those of the neighboring soils, i.e., enriched REE content, a greater ratio of light REEs to heavy REEs, greater δCe values, and lower δEu values relative to those in the carbonate rocks. The REE signatures in the silt and sand fractions of the sediments are similar to those in the soils and carbonate rocks, respectively. The REE content, LREE/HREE, and δCe values in the sediments strongly negatively correlate with the carbonate content, indicating an intense carbonate effect on the REE geochemistry. The content of acid-insoluble residues is obviously positively correlated with ∑REEs in the sediments, and a negative relationship is observed between ∑REEs and the ratio of calcite to quartz in the sediments.Conclusions
The sediments in the JNR originate from eroded soils and authigenic travertine deposits in the lakes. It is proposed that the increased ∑REEs in the sediments resulted from the elevated proportion of soil particles in lacustrine deposits was due to increasing soil erosion intensity. This hypothesis is evidenced by the coupling of ∑REEs with the intensity of soil erosion and anthropogenic activities in the JNR. In karst drainage, the total REE concentration might be a potentially powerful indicator for reconstructing the history of soil erosion. 相似文献9.
Pedotransfer functions based on general purpose Freundlich isotherms (GPF) were derived for Cd using different combinations of input variables or development conditions. The models match the criterion of flexibility as they were derived from data of 497 soil samples, which had strongly varying soil characteristics. The prediction efficiency of the approaches was investigated by comparison of measured and simulated sorption data for 124 independent soil samples. The parameterisation of the GPF shows that models derived from data of batch sorption experiments by multiple linear regression achieve best goodness-of-fit and statistical consistency. The use of extraction data or nonlinear regression analysis results in greater deviations from the statistical optima. The best overall performance considering parameterisation and validation was observed for the models including (a) the variables ‘proton activity’, ‘clay content’, ‘soil organic carbon’, ‘sum of dithionite-extractable Fe- and Mn-oxides’ or (b) the variables ‘proton activity’, ‘potential cation exchange capacity’, ‘sum of dithionite-extractable Fe- and Mn-oxides’. 相似文献
10.
Julia Mihajlovic Luise Giani Hans-Joachim Stärk Jörg Rinklebe 《Journal of Soils and Sediments》2014,14(8):1417-1433
Purpose
The purpose of this study was (1) to determine the vertical distribution of rare earth element (REE) concentrations, stocks, and geochemical fractions in two different marsh soil profiles and (2) to quantify the relations between REEs and soil properties.Materials and methods
A sandy Fluvisol recently flooded by tidal water and a clayey Gleysol landward the dike impacted by fluctuating groundwater levels served as reference marsh soils. An aqua regia extraction was used to determine the concentrations of REEs; additionally, a sequential extraction procedure developed by the Commission of the European Communities Bureau of Reference was conducted to assess the geochemical fractions (exchangeable, reducible, oxidisable, residual fraction) of REEs. Both extractions were carried out according to genetic horizons. The stocks of REEs were calculated and the relations between physico-chemical soil properties and concentrations/mobility of REEs were quantified via correlation analysis.Results and discussion
The aqua regia extractable REE concentrations and stocks of the Gleysol were about two times higher compared to the Fluvisol since the Gleysol was more clayey and REEs might adsorb onto clay minerals. We have detected small differences of REE concentrations and geochemical fractions between the horizons of the single profiles. Rare earth elements existed mainly in residual or reducible fraction, followed by oxidisable, and water soluble/exchangeable/carbonate bound fraction. The most striking difference between the two marsh soil profiles regarding the geochemical fractions was the higher residual fraction in the Fluvisol than in the Gleysol what seemed to be due to the lower aqua regia extractable concentration in the former.Conclusions
The aqua regia extractable concentration as well as reduction and oxidation processes of (amorphous) iron and manganese complexes seemed to have the most important impact on the geochemical fractions of REEs in the studied marsh soil profiles. In future, those findings should be verified in further marsh soils worldwide. In particular, future studies should elucidate the specific release kinetics of REEs and their determining factors. 相似文献11.
测定了具有代表性的4种母质发育、3种水育型的红壤性水稻土及起源土壤的可溶性稀土(REEs)和稀土总丰度(∑REE),分析了REEs的分布特征及与∑REE的相关,研究了经酸碱调节后土壤REEs与pH值的关系,结果表明:(1)不同母质发育的供试土壤REEs平均值依石英闪长岩母质土壤系列、凝灰岩母质土壤系列、黑云母花岗岩母质土壤系列、玄武岩母质土壤系列顺序递减。(2)供试土壤REEs与∑REE的相关不显著。(3)起源土壤剖面中REEs具有明显自上而下增大的趋势,而不同水育型水稻土剖面的REEs分布各有特征,但总的趋势是自上而下减少。(4)经酸度调节后供试土壤的REEs随着土壤pH值的提高而下降,呈显著的幂函数相关。 相似文献
12.
In order to evaluate the possibility of contamination of soil with trace elements by the application of sludges to soil, the contents of rare earth elements (REEs; La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) and other trace elements (Be, As, Ag, Cd, Sb, Cs, Bi, and U) in wastewater treatment sludges were determined. In sludges of night soil treatment plants (night soil sludges) and sludges of wastewater treatment plants in the food industry (food industry sludges), the distribution patterns of REEs normalized versus average REEs in the continental crust were almost flat. It was considered that the REE patterns of uncontaminated sludges reflected the pattern of the continental crust. The crust-normalized REE patterns of sludges of wastewater treatment plants in the chemical industry (chemical industry sludges) and municipal sewage sludges did not always show flat plots. The sludges that did not show a flat REE pattern were considered to be contaminated with some of the REEs. The coefficient of variation of each element determined among the 10 samples of night soil sludges and the 14 samples of sewage sludges ranged from 34 to 77% and from 26 to 84%, respectively. Among the 10 samples of food industry sludges and the 10 samples of chemical industry sludges, the coefficient ranged from 60 to 143% and from 67 to 172%, respectively. The variations of the content of each element among the food industry sludges or the chemical industry sludges were larger than those among the night soil sludges or the sewage sludges. The contents of Be, As, Cs, REEs, and U in all the sludges were lower than or the same as those in a field soil. Some of the food and chemical industry sludges contained larger amounts of Ag, Cd, and Sb than the soil. All the night soil sludges and sewage sludges contained much larger amounts of Ag and Bi than the soil. 相似文献
13.
Yu. N. Vodyanitskii 《Eurasian Soil Science》2010,43(11):1244-1254
Iron hydroxides are subdivided into thermodynamically unstable (ferrihydrite, feroxyhyte, and lepidocrocite) and stable (goethite)
minerals. Hydroxides are formed either from Fe3+ (as ferrihydrite) or Fe2+ (as feroxyhyte and lepidocrocite). The high amount of feroxyhyte in ferromanganic concretions is proved, which points to
the leading role of variable redox conditions in the synthesis of hydroxides. The structure of iron hydroxides is stabilized
by inorganic elements, i.e., ferrihydrite, by silicon; feroxyhyte, by manganese; lepidocrocite, by phosphorus; and goethite,
by aluminum. Ferrihydrite and feroxyhyte are formed with the participation of biota, whereas the abiotic formation of lepidocrocite
and goethite is possible. The iron hydroxidogenesis is more pronounced in podzolic soils than in chernozems, and it is more
pronounced in iron-manganic nodules than in the fine earth. Upon the dissolution of iron hydroxides, iron isotopes are fractioned
with light-weight 54Fe atoms being dissolved more readily. Unstable hydroxides are transformed into stable (hydr)oxides, i.e., feroxyhyte is spontaneously
converted to goethite, and ferrihydrite, to hematite or goethite. 相似文献
14.
Effects of spraying rare earths on contents of rare Earth elements and effective components in tea 总被引：4，自引：0，他引：4
Rare earth (RE) fertilizer is widely applied in China to increase the yield and the quality of crops including tea. However, the effects of spraying RE fertilizer on the contents of rare earth elements (REE) and effective components in tea are unknown. The results from basin and field experiments show that the values of the REE concentrations in new shoots of tea plants and the concentration of REE in the soil (REE/REEs) either from control basins or from treatment basins were smaller than those in other parts of tea plant and similar between control and treatment. The longer the interval between spraying RE fertilizer and picking the shoots of tea plants, the less the effects from spraying. About 80% summation operator REE (the sum of the concentrations of 15 REE) in tea, whether it came from spraying or not, was insoluble in the infusion. About 10% the soluble REE of summation operator REE in tea infusion was bound to polysaccharide, and the amount of REE bound polysaccharide decreased over time. At least a 25 day safety interval is needed between spraying and picking if the microelement fertilizer is used, in order to enhance tea output and to ensure tea safety. 相似文献
15.
[目的]掌握稀土元素(REE)示踪土壤侵蚀和泥沙来源的方法,明确其不确定性来源,对正确运用该方法获得可靠的侵蚀速率和泥沙源地贡献结果具有重要意义。[方法]基于前人运用REE示踪土壤侵蚀速率和泥沙来源的研究成果,总结了REE示踪土壤侵蚀的基本技术路线及其在水蚀、风蚀和泥沙来源研究中的应用,探讨了REE示踪土壤侵蚀和泥沙来源研究中的不足。[结果]分析认为REE虽是理想的示踪剂,但REE示踪法仍存在影响示踪土壤侵蚀和泥沙来源准确性的关键方面需要改进,包括REE与土壤结合方式与机理、长期监测或复杂环境下随淋溶、径流的迁移以及植被吸收利用等。在未来研究中应重点关注大量释放REE对土壤、植物、环境健康的影响以及REE示踪法与复合指纹识别法的结合运用等。[结论]研究结果为提高REE示踪土壤侵蚀结果的准确性,运用该方法开展其他侵蚀类型研究,与复合指纹识别法结合辨别大区域的泥沙来源奠定基础。 相似文献
16.
Eroding rills evolve morphologically in time and space. Most current studies on rill erosion use spatially averaged soil erosion data, providing little information on soil erosion dynamics. A method is proposed to use rare earth elements (REEs) to trace sediment distribution in eroding rills. Laboratory flume simulation experiments were conducted at three flow rates (2, 4 and 8 litres minute?1) and five slope gradients (5, 10, 15, 20 and 25°) with three replicates of each treatment. The rills, of 8 m length, were subdivided into 10 equal segments of 0.8 m length and 0.1 m width, with a different REE applied to each segment. We derived computational formulae for estimating the distribution of eroded amounts along the rills. The actual erosion distribution along rills was then estimated with the data from the experiments. The precision of the REEs for tracing rill erosion was analysed. The results showed that sediment concentration increased with rill length, but the increased rate (the slope of the curve) flattened gradually. Sediment yields increased with slope gradients and flow rates, but the slope gradients had a greater effect on sediment concentration than flow rates, and greater flow rates caused more rill erosion and soil loss under the same slope gradient. The results also demonstrated the feasibility of using REEs to trace the dynamic processes of rill erosion. 相似文献
17.
超富集植物对稀土元素吸收转运解毒与分异的研究进展 总被引：1，自引：1，他引：1
稀土是重要的战略资源,在现代高科技行业和农业生产中发挥着重要的作用。随着稀土需求量的与日俱增,稀土矿山开发加剧,产生了大面积的稀土废弃尾砂地进而污染农田,对当地生态环境和居民健康构成威胁。植物采矿是指在金属污染地上种植超富集植物,在恢复植被和修复污染土壤的同时,还可通过收割地上部实现金属回收利用,是一种原位和低成本的污染土壤修复手段。探究超富集植物重金属富集机理是实现植物采矿的基础,但相对于Ni、Zn、As等超富集植物的研究,稀土超富集植物吸收转运和耐受稀土机制的研究仍然缺乏。本文结合近年国内外研究,从植物富集稀土的四个关键过程综述超富集植物对稀土的吸收、转运和分布解毒机制以及与稀土分异之间的关系,并提出超富集植物中稀土分异的概念模型。 相似文献
18.
Yu Ruilian Lin Chengqi Yan Yu Hu Gongren Huang Huabin Wang Xiaoming 《Journal of Soils and Sediments》2019,19(3):1499-1510
Purpose
The purposes of this paper are to investigate the geochemical characteristics of rare earth elements (REEs) in the surface sediments of Jiulong River, southeast China, to probe the provenance compositions of the sediments, and to analyze the potential anthropogenic influence on REEs in the sediments. REEs and Sr-Nd isotopes were selected as the tools because REEs can be used to identify the anthropogenic effects on sediments and Sr-Nd isotopes have been widely known as powerful tracers for provenance analysis.
Materials and methodsFifty-three samples of surface sediments (0~5 cm) were collected from Jiulong River. The concentrations of REEs and Sr-Nd isotopic compositions in the surface sediments were determined by inductively coupled plasma mass spectrometry (ICP-MS) and thermal ionization mass spectrometry (TIMS), respectively. The chondrite-normalized and WRAS-normalized REEs patterns, enrichment factor, plots of La-Th-Sc and La/Yb-∑REE, and plots of εNd(0) vs 87Sr/86Sr and εNd(0) vs δEu are presented.
Results and discussionThe mean concentration of ΣREEs in the surface sediments of Jiulong River was 254.25 mg kg?1. The mean values of ΣLREEs (227.6 mg kg?1), ΣHREEs (26.64 mg kg?1), and (La/Yb)N ratios (9.24) suggested an enrichment of LREEs compared to HREEs. Negative Eu anomalies were observed in the surface sediments. The distribution patterns of REEs in the surface sediments from different areas of Jiulong River were remarkably similar. The values of 87Sr/86Sr, 143Nd/144Nd, and εNd(0) were 0.714091~0.733476, 0.511875~0.512271, and ??14.88~??7.16, respectively. The plots of εNd(0) vs 87Sr/86Sr, εNd(0) vs 1/[Nd], and εNd(0) vs δEu indicated that the sediments in Jiulong River were mainly derived from natural geological processes and the REEs might be also influenced by anthropogenic activities such as Fujian Pb-Zn deposit, coal ash, and industrial sludge.
ConclusionsThe REEs in the surface sediments at different sites are similar in geochemical characteristics, with a right-inclined distribution pattern and higher enrichment of light REEs (LREEs) compared to heavy REEs (HREEs), and a negative Eu anomaly but no evidence of Ce anomaly. The sediments in Jiulong River were mainly derived from natural geological processes (granite and magmatic rocks), and the REEs in the sediments were also influenced by anthropogenic activities (Fujian Pb-Zn deposit, coal ash, and industrial sludge).
相似文献19.
Journal of Soils and Sediments - The geochemistry of rare earth elements (REEs, La to Lu) in suspended sediments (SS) is generally controlled by weathering processes and the water environment.... 相似文献
20.
Juscimar Silva Jaime Wilson Vargas de Mello Massimo Gasparon Walter Ant?nio Pereira Abrah?o 《Water, air, and soil pollution》2012,223(9):5707-5717
Dissimilatory iron-reducing bacteria play a fundamental role in catalysing the redox transformations that ultimately control the mobility of As in anoxic environments, a process also controlled by the presence of competing anions. In this study, we investigated the decoupling of As from loaded Al and Fe (hydr)oxides by competing anions in the presence of iron-reducing bacteria. Hematite, goethite, ferrihydrite, gibbsite and three aluminium-substituted goethites (AlGts) were synthesised and loaded with arsenate, followed by anaerobic incubation with different phosphate or carbonate-containing media in the presence of catalytic iron-reducing bacteria. Soluble Al, As, Fe and P contents were measured in aliquots by inductively coupled plasma optical emission spectrometry following periodical sampling. Shewanella putrefaciens cells were able to utilise both non-crystalline and crystalline Fe (hydr)oxides as electron acceptors, releasing Fe and As into solution. Phosphate and carbonate affected the Fe bioreduction, probably due to the precipitation of metastable mineral phases and also to phosphate-induced stabilisation on the hydroxide surfaces. Phosphate precipitation acted as a sink for As, thus limiting its mobilisation. The highest fraction of desorbed As by phosphate was observed for gibbsite, followed by AlGts. Similarly, gibbsite showed significant amounts of arsenate displaced by carbonate. In spite of its low crystallinity, ferrihydrite was the most efficient compound in retaining arsenate, possibly due to As co-precipitation. This study provides new insight into the management of As-contaminated soils and sediments containing Al-goethites and gibbsite, where the Fe activity may be too low to co-precipitate As-bearing vivianite. Thus, the dynamics of As(V) in flooded soils are significant in agriculture and environmental management. 相似文献