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Regional Geochemical Characteristics and Influence Factors of Soil Elements in the Pearl River Delta Economic Zone, China 被引量:2
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作者 Lei Dou Tingting Li 《International Journal of Geosciences》 2015年第6期593-604,共12页
Soil heavy metal pollution is one of the main environmental problems in Pearl River Delta Economic?Zone of China. Based on multi-purpose regional geochemical survey, regional eco-geochemical assessment, local eco-geoc... Soil heavy metal pollution is one of the main environmental problems in Pearl River Delta Economic?Zone of China. Based on multi-purpose regional geochemical survey, regional eco-geochemical assessment, local eco-geochemical assessment and comprehensive appraisal, the eco-geochemical survey and assessment in Pearl River Delta Economic Zone of 41,698 km2?were completed. Samples from soils were collected in accordance with the two-layer grid method. Totally 54 elements and indicators for soils were determined. Compared to deep soils, the sampled surface soils are enriched in OrgC, N, P, Cd, S,Hg, Ag, B, Au, S and poor with As, Ni, I, Co, Cr, V, MgO, Sc, Al2O3, Fe2O3?etc. The characteristics of geochemical reference value of element in soil that inherited soil parent material and regional elements combined features reflected that the elements enriched in the soil was interrelated with acid rock, sandstone and shale. The spatial distribution characteristics of element regional geochemistry were conditional by regional environmental geological conditions,and effected by human activities. The Pearl River Delta plain is a typical geochemical landscape area with regional anomaly of multiple-elements. The north, western and eastern parts of the Pearl River Delta Economic Zone are quite different in geochemical features due to regional geological background, soil parent materials, geomorphic characteristics and human activities. Environment quality evaluation results show that the grade I and grade II soil accounted for 19.9% and 57.3% of the total area. Many samples that widely distributed in the economic developed of Pearl River Delta Plain area reached the third-grade of national soil environment standard. The soil enriched in Cd, Hg, As, and the area ratio accounting for 22.8% of the total area. It is mainly controlled by the geochemical background, the Pearl River Delta formation evolution process, especially the marine transgression process lead to Cd, Cu, Zn and Pb enrichment in Pearl River Delta plain. At the same time, under the influence of higher pressure of human activities, all kinds of exogenous input material carrying heavy metal pollutants on soil environmental quality also could not to ignore. 展开更多
关键词 Regional GEOCHEMICAL Characteristic soil elementS Source of ANOMALOUS elementS Influence Factors PEARL River Delta Economic Zone China
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Analysis of the Fertilizing and Bioremediation Potential of Leaf Litter Compost Amendment in Different Soils through Indexing Method
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作者 Sophayo Mahongnao Pooja Sharma +1 位作者 Arif Ahamad Sarita Nanda 《Journal of Environmental Protection》 2024年第3期265-297,共33页
This research study explored the efficacy of leaf litter compost as a sustainable soil amendment with the objective of promoting soil health and mitigating the accumulation of potentially toxic elements. The investiga... This research study explored the efficacy of leaf litter compost as a sustainable soil amendment with the objective of promoting soil health and mitigating the accumulation of potentially toxic elements. The investigation encompassed the impact of various organic compost amendments, including leaf compost, cow dung manure, kitchen waste compost, municipal organic waste compost, and vermicompost. The study employed Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to evaluate soil nutrient levels and concentrations of Potentially Toxic Elements (PTEs) such as arsenic, chromium, cadmium, mercury, lead, nickel, and lithium. The fertilization and bioremediation potential of these compost amendments are quantified using an indexing method. Results indicated a substantial increase in overall nutrient levels (carbon, nitrogen, phosphorus, potassium, and sulfur) in soils treated with leaf compost and other organic composts. Fertility indices (FI) are notably higher in compost-amended soils (ranging from 2.667 to 3.938) compared to those amended with chemical fertilizers (ranging from 2.250 to 2.813) across all soil samples. Furthermore, the mean concentrations of PTEs were significantly lower in soils treated with leaf compost and other organic compost amendments compared to those treated with chemical fertilizers amendments. The assessment through the indexing method revealed a high clean index (CI) for leaf compost amendment (ranging from 3.407 to 3.58), whereas the chemical fertilizer amendment exhibits a relatively lower CI (ranging from 2.78 to 3.20). Consequently, leaf compost and other organic composts exhibit the potential to enhance sustainable productivity, promoting soil health and environmental safety by improving nutrient levels and remediating potentially toxic elements in the soil. 展开更多
关键词 Bio-Compost soil Fertility Potentially Toxic elements BIOREMEDIATION
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Soil Profile Concentration Distributions of Antimony and Bismuth across Southeastern Missouri (USA)
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作者 Michael Aide 《Journal of Environmental Protection》 2024年第5期537-551,共15页
Recent research has suggested that increased industrial and technological utilization of antimony and bismuth necessitates greater research to determine the soil and water chemistry and the environmental risks associa... Recent research has suggested that increased industrial and technological utilization of antimony and bismuth necessitates greater research to determine the soil and water chemistry and the environmental risks associated with these elements. The near-total soil profile concentrations of antimony and bismuth were determined for key soil series across southeastern Missouri. The antimony concentrations ranged from 0.65 to 0.08 mg kg<sup>−</sup><sup>1</sup>, whereas the bismuth soil profile concentrations ranged from 0.92 to 0.03 mg kg<sup>−</sup><sup>1</sup>. Most pedons showed antimony concentrations ranging from 20 to 30 mg kg<sup>−</sup><sup>1</sup>, whereas bismuth concentrations were commonly 10 to 20 mg kg<sup>−</sup><sup>1</sup>. For soils having argillic horizons, antimony and bismuth concentrations were greater for the illuvial horizons than the eluvial horizons, whereas Entisols, Inceptisols, and one Vertisol showed rather uniform antimony and bismuth concentrations, features paralleling the soil texture distribution. Both antimony and bismuth showed significant correlations with iron. 展开更多
关键词 Trace elements ANTIMONY BISMUTH soilS Group 15
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Soil Profile Concentration Distributions of Aluminum, Gallium, Indium and Thallium across Southeastern Missouri
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作者 Michael Aide 《Journal of Geoscience and Environment Protection》 2024年第1期80-92,共13页
The soil chemistry of gallium, indium, and thallium is not well defined, particularly with emerging evidence that these elements have toxic properties and may influence food safety. The purpose of this investigation w... The soil chemistry of gallium, indium, and thallium is not well defined, particularly with emerging evidence that these elements have toxic properties and may influence food safety. The purpose of this investigation was to estimate the soil concentrations of gallium, indium, and thallium and determine if these elements have a soil chemistry like aluminum and therefore demonstrate significant concentration correlations with aluminum. Twenty-seven soil series were selected, and the elemental concentrations were determined using aqua regia digestion with analytical determination performed using inductively coupled plasma emission-mass spectroscopy. The concentrations of gallium, indium, and thallium generally compared with the known literature. Aluminum-gallium and aluminum-thallium exhibited significant concentration correlations across the soil horizons of the sampled soils. Aluminum, gallium, and thallium did demonstrate concentration increases in soil horizons having illuviation of phyllosilicates, implying these phyllosilicates have adsorption and isomorphic substitution behaviors involving these elements. 展开更多
关键词 Trace elements GALLIUM INDIUM THALLIUM soils ALUMINUM
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CHARACTERISTICS OF NATURAL CONTENTS OF CHEMICAL ELEMENTS IN SOILS OF KARAKORUM-WEST KUNLUN MOUNTAIN REGION
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作者 Xa Zenglu Li Senzhao Lu Jinfa(Institute of Geography, CAS, Bejing 100101People’s Republc of China) 《Journal of Geographical Sciences》 SCIE CSCD 1994年第Z1期119-137,共19页
Natural contents of 23 elements in soils of Karakorum-West Kunlun Mts are studied. By comparison of natural contents andcalculation of regional differentiation coefficients, similarity anddchrence of elemental content... Natural contents of 23 elements in soils of Karakorum-West Kunlun Mts are studied. By comparison of natural contents andcalculation of regional differentiation coefficients, similarity anddchrence of elemental contents between soils of the region and thatof China and of the world are discussed. Through main componentanalysis, relation of intergrowth and realignment among elementsin soils and characteristics of cluster expressed in soil types are alsodiscussed. Coherence of elements in soi1s and characteristics ofregional dtherence of the elements are clarified. The concernedregion is abound in natural resources. Research on natural contentsof chemical elements in soils of the region is significant forstudying elemental chemical geography and environmentalgeochemistry. Besides, it also offers necessary data for explorationand development of this region. 展开更多
关键词 soil element differential characteristics Karakorum-West Kunlun Mts
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Geographical Tendencies of Trace Element Contents in Soils Derived from Granite,Basalt and Limestone of Eastern China 被引量:4
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作者 CHENJING-SHENG PANMAO 《Pedosphere》 SCIE CAS CSCD 1993年第1期45-55,共11页
92 soil samples were collected from granite,basalt and limestone areas of eastern China and determined for 13 trace element contents.The geographical tendencies of and factors affecting trace element contents in soils... 92 soil samples were collected from granite,basalt and limestone areas of eastern China and determined for 13 trace element contents.The geographical tendencies of and factors affecting trace element contents in soils were studied.The sequences of soil trace element contents (especially the transitional elements in the 4period) were:basalt soils> limestone soils> granite soils.The contents of trace elements in soils of granite areas and basalt areas showed great inheritance of trace element contents from the relevant parent rocks.The contents of trace elements in limestones were very low,but they became very high in limestone soils.Trace element contents of soils derived from limestone and basalt increased significantly from north to south,these tendencies were similar to the tendency of ferric oxide contents in soils.There were differences of contents of trace elements bound to ferric oxide in different kinds of parent material and in different types of soil.The correlations between the contents of trace elements and the contents of ferric oxide were better in basalt soils than in granite soils. 展开更多
关键词 矿物元素 花岗岩土壤 玄武岩土壤 石灰岩土壤 中国东部地区 区域性
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Numerical simulation of tire/soil interaction using a verified 3D finite element model 被引量:6
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作者 Namjoo Moslem Golbakhshi Hossein 《Journal of Central South University》 SCIE EI CAS 2014年第2期817-821,共5页
The compaction and stress generation on terrain were always investigated based on empirical approaches or testing methods for tire/soil interaction.However,the analysis should be performed for various tires and at dif... The compaction and stress generation on terrain were always investigated based on empirical approaches or testing methods for tire/soil interaction.However,the analysis should be performed for various tires and at different soil strengths.With the increasing capacity of numerical computers and simulation software,finite element modeling of tire/terrain interaction seems a good approach for predicting the effect of change on the parameters.In this work,an elaborated 3D model fully complianning with the geometry of radial tire 115/60R13 was established,using commercial code Solidwork Simulation.The hyper-elastic and incompressible rubber as tire main material was analyzed by Moony-Rivlin model.The Drucker-Prager yield criterion was used to model the soil compaction.Results show that the model realistically predicts the laboratory tests outputs of the modeled tire on the soft soil. 展开更多
关键词 三维有限元模型 子午线轮胎 数值模拟 相互作用 土壤强度 SOLIDWORK 验证 土壤压实
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Correlation Between Chemical Element Contents in Tree Rings and Soils 被引量:8
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1993年第4期309-319,共11页
The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining ares of lead-and zinc-dominant metals in the Xixia Mountain,Nanjing,for the determination of chemical element content... The annual growth rings of ten trees and the soils near the tree roots were sampled from the mining ares of lead-and zinc-dominant metals in the Xixia Mountain,Nanjing,for the determination of chemical element contents.The study results showed that the elemental contents in the tree rings were correlated with those in the soils,i.e.,the elemental contents in the tree rings increased with those in the soils,even in the cases of different environments and different tree species.Therefore,a time-concentration sequence could be set up on the basis of determining the elemental contents in the successive annual growth rings of trees to qualitatively reflect the annual variations of relevant elements in the soils,and a time-concentration sequence of elemental contents in soils could also be established in terms of related model to reproduce the dynamic changes of the surroundings. 展开更多
关键词 树木年轮 土壤 化学元素含量 交互关系
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Water-Soluble Rare Earth Elements in Some Soils of China 被引量:3
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作者 ZHUJIANGUO SUNJUN 《Pedosphere》 SCIE CAS CSCD 1997年第1期25-30,共6页
Water-soluble rare earth elements (WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer. Results showed that the contents of WSREEs dec... Water-soluble rare earth elements (WSREEs) of four typical soil profiles in China were determined by using a high-resolution inductively coupled plasma mass spectrometer. Results showed that the contents of WSREEs decreased from upper layer to lower layer of soils in the southern part of China with a high rainfall and low pH but increased for soils in the northern part of China with a low rainfall and relatively higher pH. Contents of WSREEs in soils were lower than 100 μg kg-1 in most casest and varied greatly with both different soils and different layers of the same profile. The highest content was 2816.3 μg kg-1 but the lowest was 17.6 μg kg-1 only. The content of individual rare earth iement (REE) in the soil solution also varied greatly with the highest one ranging from 8.4 to 1373 μg kg-1 for Ce and the lowest one from 0.05to 4.48 μg kg-1 for Lu. The sum of WSREEs in the first soil layers ranged from 121.5 to 345.6 μg kg-1.Great variations existed among ratios of REEs extracted with water to the total REEs of soils, ranging from 0.02×10-3 to 13.2×10-3. But as the upper layer was considered, the ratio showed only a small difference,ranging from 0.79×10-3 to 1.69×10-3. 展开更多
关键词 稀土元素 土壤剖面 电感耦合等离子体质谱测定法 可溶性 中国 PH值
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Trace Elements in Leccinum scabrum Mushrooms and Topsoils from K odzka Dale in Sudety Mountains, Poland 被引量:4
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作者 ZHANG Dan ZHANG Yu +6 位作者 MORAWSKA Ewa BIELAWSKI Leszek KRASINSKA Grazyna DREWNOWSKA Ma gorzata PANKAVEC Sviatlana SZYMANSKA Karolina FALANDYSZ Jerzy 《Journal of Mountain Science》 SCIE CSCD 2013年第4期621-627,共7页
In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn to Brown Birch Scaber Stalks (Leccinum scabrum) mushrooms emerged in... In the current study, we determined concentrations and transfer rates of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, P, Rb, Sr and Zn to Brown Birch Scaber Stalks (Leccinum scabrum) mushrooms emerged in the area of Sudety Mountains (Sudetes) in Poland. Fruiting bodies and topsoil samples beneath L. scabrum were collected form the K odzka Dale. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES) for final measurement. Mushrooms contained Ag, Cr, Hg, Co, Ni and Sr at < 1.0 μg/g dry weight; Ba and Pb at ~1.0 μg/g dw; Cd at < 5 μg/g dw; Cu and Mn at > 10 μg/g dw; Al and Ca at ~100 μg/g dw; Fe, Na, Rb and Zn at 100 to 500 μg/g dw, Mg at ~1,000 μg/g dw; P at ~5,000 μg/g dw and K at ~30,000 μg/g dw. Ca, Mn and Ni were nearly equally distributed between stipes and caps; stipes compared to caps were enriched in Ba, Na and Sr, while caps were enriched in Ag, Al, Cd, Co, Cr, Cu, Fe, K, P, Pb, Rb and Zn. The values of bioconcentration factor (BCF) varied highly depending on chemical element and were >1 for Ag, Cd, Cu, K, Mg, Na, P, Rb and Zn, while <1 for Al, Ba, Ca, Co, Cr, Fe, Mn, Ni, Pb and Sr. Topsoil showed elevated content of lead and mean concentration was 99 ± 32 μg/g dw, while cadmium was at 0.41 ± 0.15 and those two highly toxic to human elements occurred in edible caps of L. scabrum at 4.5 ± 2.2 and 2.9 ± 2.0 μg/g dw, respectively. 展开更多
关键词 土壤微量元素 牛肝菌 蘑菇 戴尔 波兰 电感耦合等离子体 生物富集系数 ICP-AES
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NUMERICAL ANALYSIS OF SOIL PLUG INSIDE SUCTION FOUNDATIONS DURING SUCTION PENETRATION BY DISCRETE ELEMENT METHOD 被引量:4
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作者 杜杰 丁红岩 +1 位作者 张浦阳 张超 《Transactions of Tianjin University》 EI CAS 2006年第1期61-65,共5页
通常在吸穿入期间在吸基础内升起的土壤塞子的现象是描述并且预言的份量上。thes 油塞子的形成过程被 DEM (分离元素方法) 模仿并且推测模型。渗出物流动,土壤的自我重量,房间墙上的磨擦以及在房间内的吸在这个过程被看作主要外部力... 通常在吸穿入期间在吸基础内升起的土壤塞子的现象是描述并且预言的份量上。thes 油塞子的形成过程被 DEM (分离元素方法) 模仿并且推测模型。渗出物流动,土壤的自我重量,房间墙上的磨擦以及在房间内的吸在这个过程被看作主要外部力量。结果与测试由在 BohaiSea 区域使用三种土壤类型(沙,淤泥的泥土和泥土) 执行了的一套实验室模型相比。从数字评价的土壤塞子的高度是比从模型测试结果的那些低的,主要吸压力和磨擦,抵抗在数字模拟下面以一个理想的方法被使用。 展开更多
关键词 虹吸式基础 土坝 渗流 闸墙 离散元法
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SPATIAL-TEMPORAL VARIATION OF HEAVY METAL ELEMENTS CONTENT IN COVERING SOIL OF RECLAMATION AREA IN FUSHUN COAL MINE 被引量:5
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作者 YUJun-bao LIUJing-shuang 《Chinese Geographical Science》 SCIE CSCD 2002年第3期268-272,共5页
Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp le... Grid method is employed for sampling covering soil at the test field,whic h is reclamation area filled by coal mining wastes for cropland in th e Fushun coal mine,Liaoning Province,the Northeast China.The soil samp les are taken at different locations,inclu ding three kinds of covering soil,th ree different depths of soil layers a nd four different covering ages of covering soil.The s patial-temporal variation of heavy metal element content in reclamatio n soil is stud-ied.The results indicate that the co ntent of heavy metal elements is decreasing year after year;the determin ant reason why the content of heavy metal elemen ts at 60cm depth layer is higher than t hat at 30cm depth layer and surface is fertiliz-er and manure application;the metal elements mainly come from external environment;there is no metal pollut ion coming from mother material(coal mining wastes)in plough layer of covering soil. 展开更多
关键词 土壤 重金属元素 时空分布 复垦 抚顺煤矿
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Identifying Pathfinder Elements for Gold in Multi-Element Soil Geochemical Data from the Wa-Lawra Belt, Northwest Ghana: A Multivariate Statistical Approach 被引量:2
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作者 Prosper Mackenzie Nude John Mahfouz Asigri +3 位作者 Sandow Mark Yidana Emmanuel Arhin Gordon Foli Jacob Mawuko Kutu 《International Journal of Geosciences》 2012年第1期62-70,共9页
A multivariate statistical analysis was performed on multi-element soil geochemical data from the Koda Hill-Bulenga gold prospects in the Wa-Lawra gold belt, northwest Ghana. The objectives of the study were to define... A multivariate statistical analysis was performed on multi-element soil geochemical data from the Koda Hill-Bulenga gold prospects in the Wa-Lawra gold belt, northwest Ghana. The objectives of the study were to define gold relationships with other trace elements to determine possible pathfinder elements for gold from the soil geochemical data. The study focused on seven elements, namely, Au, Fe, Pb, Mn, Ag, As and Cu. Factor analysis and hierarchical cluster analysis were performed on the analyzed samples. Factor analysis explained 79.093% of the total variance of the data through three factors. This had the gold factor being factor 3, having associations of copper, iron, lead and manganese and accounting for 20.903% of the total variance. From hierarchical clustering, gold was also observed to be clustering with lead, copper, arsenic and silver. There was further indication that, gold concentrations were lower than that of its associations. It can be inferred from the results that, the occurrence of gold and its associated elements can be linked to both primary dispersion from underlying rocks and secondary processes such as lateritization. This data shows that Fe and Mn strongly associated with gold, and alongside Pb, Ag, As and Cu, these elements can be used as pathfinders for gold in the area, with ferruginous zones as targets. 展开更多
关键词 MULTIVARIATE Analyses Multi-elements soil Geochemical Data PATHFINDER elementS GOLD NORTHWEST Ghana
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Geochemical Characteristics of Rare Earth Elements in Different Types of Soils in China 被引量:1
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作者 王立军 章申 +6 位作者 高效江 刘书娟 王玉琦 孙景信 胡蔼堂 陈红民 郭繁清 《Journal of Rare Earths》 SCIE EI CAS CSCD 1998年第1期52-59,共8页
The contents, distribution patterns, and specification of rare earth elements(REEs) in latosol(tropical zone), red earth(middle subtropical earth), yellow brown soil(northern subtropical earth), cinnamon soil(warm tem... The contents, distribution patterns, and specification of rare earth elements(REEs) in latosol(tropical zone), red earth(middle subtropical earth), yellow brown soil(northern subtropical earth), cinnamon soil(warm temperate zone), leached chernozem(temperate zone) and albic bleached soil(temperate zone) in China were determined with instrumental neutron activation analysis(NAA) and systematically studied. The results indicate that yellow brown soil, cinnamon soil, leached chernozem and albic bleached soil are characterized by light REEs(LREEs) enrichment and Eudepletion, while latosol and red earth are characterized by LREEs enrichment and Cedepletion. REEs exist mainly in a stable residual form in the six soils, and with increasing atomic number, the intermediate REEs(IREEs) of residual form have lower proportion than light and heavy REEs. For the six unstable forms, the proportions of watersoluble, exchangeable, specific absorption, and carbonate forms are lower. Appearent zonal distribution patterns of REEs were found in the form of FeMn oxides in different types of soils, and the general trend gradually decreases from southern to northern China. Proportions of REEs in bound organic matters are higher and follow the order: albic bleached soil>leached chernozem>red earth>latosol>yellow brown soil>cinnamon soil. Higher proportion of REEs exists in soils with higher proportion of organic matters. But their activation differs greatly with difference in relative proportions of loosely bound organic matter form and tightly bound organic matter form. 展开更多
关键词 Rare earth elements soil GEOCHEMISTRY
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Chrono-Sequences of Elemental Contents in Tree Ringsand Soils 被引量:3
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作者 QIANJUN-LONG KESHAN-ZHE 《Pedosphere》 SCIE CAS CSCD 1994年第1期27-33,共7页
Chrono-SequencesofElementalContentsinTreeRingsandSoilsQIANJUN-LONGandKESHAN-ZHE(1NanjinginstituteofGeography... Chrono-SequencesofElementalContentsinTreeRingsandSoilsQIANJUN-LONGandKESHAN-ZHE(1NanjinginstituteofGeographyandLimnology,Acad... 展开更多
关键词 树木年轮 元素含量 土壤含量 年代序列 本底值
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Regression Analysis of Nutrient Elements between Soil and Tobacco Leaves and Their Influences on Aroma Quality of Flue-cured Tobacco 被引量:1
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作者 Xueqin XU Xiaolan LI +2 位作者 Zhiyan CHEN Defen ZENG Aifei XU 《Agricultural Science & Technology》 CAS 2014年第3期493-498,共6页
This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences... This study aimed to analyze the relationship between nutrient elements K, Ca, Mg, Cu, Mn, Zn and Fe in tobacco-planting soils and tobacco leaves from six main tobacco-producing areas, and to investigate the influences of these elements on chemical composition and aroma components in tobacco leaves. Results showed that there were certain relationship between contents of nutrient elements in tobacco-planting soils and contents of corresponding elements in tobacco leaves; various elements exhibited different influences on the aroma quality of flue-cured tobacco. Based on the actual situation of nutrient contents in soils from different tobaccoproducing areas, contents of various elements in tobacco leaves should be regulated by soil fertilization and foliar spraying, thereby improving the aroma quality of flue-cured tobacco. 展开更多
关键词 土壤养分含量 营养元素 香气质量 烟叶 回归分析 烤烟 烟草种植 香气成分
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Does the long-term application of calcium superphosphate lead to an increase of the soil rare earth element contents? 被引量:2
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作者 ZHANG Yun DENG Li-bin YE Wan-Hui 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2006年第1期130-134,共5页
In order to test whether the long-term application of calcium superphosphate leads to an increase of the soil rare earth element contents, superphosphate fertilized soils were sampled and compared with superphosphate-... In order to test whether the long-term application of calcium superphosphate leads to an increase of the soil rare earth element contents, superphosphate fertilized soils were sampled and compared with superphosphate-free soils. Spectrophlame inductively coupled argon plasma atomic emission spectrophotometer (ICP-AES) was applied to quantify the rare earth elements (REEs). The total rare earth element contents in calcium superphosphate from Zhijin County, west part of Guizhou Province, China (produced by the sulphuric acid treatment of the apatites) are about 2.54 mg/g. Between 38 and 189 gREEs/hm^2 per year (available for plants, estimated by 2% citric acid) will be introduced into the soil solution when applying 320 kg superphosphate/hm^2 per year. The long-term application of the latter will increase the REE content by about 18% in the soil surface layer in these areas. A statistically significant increase of the content of the rare earths in some cultivated soils should not be neglected. 展开更多
关键词 rare earth elements calcium superphosphate soil
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Ratios of Closely Related Elements in Soil and Their Implications 被引量:1
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作者 XINGGUANG-XI HOUWEN-HUA 《Pedosphere》 SCIE CAS CSCD 1991年第4期333-343,共11页
This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil... This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil formation,material transport and environmental pollution.Results show that the effect of soil-forming processes on the ratios of closely related elements varied with different elements,and became greater in the sequence of Ce/La <V/Cr≈Ni/Co<Zn/Cu≈Zn/Pb<Zn/Cd<Mn/Cr<Ba/Sr.The magnitude of the variation in the ratios of closely related elements depended on the chemical properties of the elements themselves,on the one hand,and the parent material and climatic conditions on the other.The ratio of Ba/Sr showed a distinct zonality,decreasing gradually in the sequence:cool temperate zone acid soils>grassland soils>desert soils and increasing gradually from the semi-arid subhumid zone soils>the temperate zone neutral soils>the north subtropic zone soils>tropical and subtropical acid soils. 展开更多
关键词 元素丰度 土壤形成 土壤成分 物质运移 元素比率
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The Estimation of Soil Trace Elements Distribution and Soil-Plant-Animal Continuum in Relation to Trace Elements Status of Sheep in Huangcheng Area of Qilian Mountain Grassland,China 被引量:10
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作者 WANG Hui LIU Yong-ming +7 位作者 QI Zhi-ming WANG Sheng-yi LIU Shi-xiang LI Xia WANG Hai-jun WANG Xiao-li XIA Xin-chao ZHU Xin-qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第1期140-147,共8页
The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer (0-20 cm) in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland,... The purpose of the present study was to survey contents of trace elements of Cu, Mn, Fe, and Zn in the surface layer (0-20 cm) in the soil, pasture and serum of sheep in Huangcheng area of Qilian mountain grassland, China. Also the soil-plantanimal continuum was analyzed. Soil (n=300), pasture (n=60), and blood serum samples from sheep (n=480) were collected from Huangcheng area of Qilian mountain grassland, China. The contents of trace element in the samples were analyzed by atomic absorption spectrophotometer after digestion. The soil trace elements density distribution shows a ladder-like pattern distribution. Equations developed in the present study for prediction of Fe (R2=0.943) and Zn (R2=0.882) had significant R2 values. 展开更多
关键词 trace elements minerals deficiency soil type Qilian mountain grassland correlation
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The Boundary Element Method for Pile-Soil Interaction 被引量:1
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作者 Liu Xingye Associate Professor, Department of Civil Engineering, Tianjin University, 300072 Tianjin 《China Ocean Engineering》 SCIE EI 1992年第3期317-330,共14页
In this paper, several mathmatical models for the pile- soil interaction are outlined. The Boundary Element Method is one of the very effective methods for the reasonable models of elasticity and elastoplasticity. The... In this paper, several mathmatical models for the pile- soil interaction are outlined. The Boundary Element Method is one of the very effective methods for the reasonable models of elasticity and elastoplasticity. The major of this paper is concerned with the Boundary Element Method for the pile-soil interaction, including general methods and calculating formulation of static and dynamic analysis of the pile and pile groups. Some results of analysis are also given. 展开更多
关键词 PILE soil pile-soil interaction boundary element method BE-FE coupled method
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