Spatial distribution, source identification and affecting factors of heavy metals contamination in urban–suburban soils of Lishui city, China

An investigation on spatial distribution, possible pollution sources, and affecting factors of heavy metals in the urban–suburban soils of Lishui city (China) was conducted using geographic information system (GIS) technique and multivariate statistics. The results indicated that the topsoils in urban and suburban areas were enriched with metals, such as Cd, Cu, Pb, and Zn. Spatial distribution maps of heavy metal contents, based on geostatistical analysis and GIS mapping, indicated that Cd, Cr, Cu, Mn, Ni, Pb, and Zn had similar patterns of spatial distribution. Their hot-spot areas were mainly concentrated in the densely populated old urban area of the city. Multivariate statistical analysis (correlation analysis, principal component analysis, and clustering analysis) showed distinctly different associations among the studied metals, suggesting that Cr, Cu, Ni, Pb, Cd, and Zn had anthropogenic sources, whereas Co and V were associated with parent materials and therefore had natural sources. The Cd, Cr, Ni, Pb, and Zn contents were positively correlated with soil organic matter, pH, and sand content (p < 0.01). It is concluded that GIS and multivariate statistical methods can be used to identify hot-spot areas and potential sources of heavy metals, and assess soil environment quality in urban–suburban areas.     

Metal contamination of soils at Scott Base,Antarctica

Soil samples taken from excavated pits on traverses across New Zealand’s Scott Base, Antarctica, were leached with water and 0.01 M HNO₃ and the leachates analysed for Ag, Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. The soils had high conductivity and pH values generally increasing with depth and in the range 8.3–10.1. The water leachate generally contained most of the extractable metals except Mn and Cd, and As. Linear relationships were observed between some metals leached into alkaline solution and the Fe in those solutions. The ratios to Fe were comparable to those of the host basanite, and this observation is interpreted as showing that these metals are incorporated in fine mineral particulates derived directly from the rock mass. Outliers in leachable metal concentrations in the soils indicated appreciable contamination of the soil from anthropogenic sources with Ag, Cd, Cu, Pb and Zn as well as As. In some locations high concentrations of Ag and Cd correspond to specific sources and drainage channels. High concentrations of Pb were widely spread and in the top soil layers whereas the elevated concentrations of Zn were distributed throughout the soil profiles indicating atmospheric sources and different mobilities within the soils. Transport within the soils is evident for some metals, as is lateral movement over and through the soils.     

Sedex型矿床成矿系统

系统总结了Ｓｅｄｅｘ型矿床产出的构造背景、地质环境、矿床地质地球化学特征、矿化流体来源及成矿模式等问题。结合某些最新研究成果,对该类型矿床的Ｐｂ、Ｓｉ、Ｂ同位素地球化学进行了综合研究,并以加拿大科迪勒拉地区页岩容矿的Ｚｎ Ｐｂ矿床、中国大厂锡多金属矿床及澳大利亚布罗肯希尔Ｐｂ Ｚｎ Ａｇ矿床为例,深入讨论了Ｐｂ、Ｓｉ、Ｂ的来源及其对矿床成因的指示意义。对产于不同地质环境下现代海底热液成矿系统的研究证明,有沉积物覆盖和无沉积物覆盖海底成矿热流体的化学组成及Ｐｂ、Ｓｒ、Ｂ稳定同位素地球化学明显不同。前者富含与陆壳物质有关的金属组合及ＮＨ４,并富含放射成因Ｐｂ和Ｓｒ的组分,后者富含与洋壳玄武岩有关的金属组合,但特别贫ＮＨ４。这种不同与古代Ｓｅｄｅｘ型和塞浦路斯型矿床之间化学组成的差别十分相似,它意味着前者成矿物质主要来源于下伏陆壳岩石,并为其富含Ｂ,Ｂａ,Ａｇ,Ａｓ,Ｓｂ,Ｗ,Ｓｎ,Ｈｇ,Ｍｎ等元素提供了合理的解释。在此基础上,笔者指出,在特定地球化学背景下,上述那些元素也能形成独立的Ｓｅｄｅｘ型矿床,同时强调了注意寻找这种新型矿床的重要性     

Content of the potentially harmful elements in soil around the major coal-fired power plant in Serbia: relation to soil characteristics,evaluation of spatial distribution and source apportionment

The concentrations and spatial distribution of nine potentially harmful elements (PHEs), namely Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn, and their relation to soil properties were investigated in thirty soil profiles (0–50 cm depth) sampled around the largest Serbian coal-fired power plant (CFPP) “Nikola Tesla A.” Soil properties were determined following standard procedures, and total contents of PHEs were analyzed by atomic absorption spectrometer. Concentrations of Cd, Co, Fe, Mn, Pb and Zn were the highest in soil profiles sampled 1 km away from the CFPP, concentrations of Ni and Cu gradually increased up to 4 km, and the highest Cr concentrations were measured in samples taken 6 km away from the CFPP. The highest concentration of PHEs analyzed, except Mn, corresponded with predominant wind directions. Depth did not show significant impact on distribution of any PHEs investigated. Among soil properties, the total organic carbon showed the closest relationship with the PHEs. Data were processed by a principal component analysis which enabled distinguishing anthropogenic from natural influences on soil properties and PHE contents. Although the impact of CFPP operations is obvious, assets of principal component analysis did not allow clear distinction of CFPP’s contribution from parent material in enrichment of PHE contents in the soil in the study area.     

固体聚合膜电解浓集法测量天然水中低含量氚的化学淬灭效应研究

固体聚合膜电解浓集法是浓缩氚含量较低(1 Bq/m~3)的天然水样的常用方法,但因水样自身含有杂质离子或电解装置聚合膜带入杂质进入浓集液,使浓集液偏酸性,在测量过程中易产生化学淬灭效应,导致氚的测量值偏低。本文研究了水样自身存在的杂质离子和聚合膜上残留的杂质离子、样品溶液的pH值及其电导率所产生的化学淬灭效应的影响,实验表明,为减少化学淬灭效应,提高测量低含量氚的准确性,需保证水样溶液呈中性,电导率≤1μS/cm,同时避免杂质沉积在聚合膜上。如果水样溶液的pH值偏酸性、电导率大于1μS/cm,可采用酸碱混合型离子交换树脂去除水样中自身的杂质;对于聚合膜引入的杂质,可在电解后的水样中加入微量氨水将其pH值调节至中性。     

Dust deposition in the central Mediterranean (Tyrrhenian and Adriatic Seas): Relationships with marine sediments and riverine input

Major (Al, Ca, Fe, Mg, Mn, Si) and minor (Cd, Pb, Zn) elements of aeolian dust samples collected onboard ship around Italy were analysed, and the concentrations of metal in the dusts were in good agreement with previously published data from the Mediterranean Sea.
The elemental composition of dust samples collected in four subareas (Adriatic, Ionian, Tyrrhenian, and Sicily Channel) was compared with the composition of marine deep sediments obtained in the same regions: Mn, Al, Cd and Zn contents differentiated between the four areas in both sets of samples, suggesting a possible 'geochemical signature' of the atmospheric crustal contribution in marine deep sediments.
An estimate of the relative contribution of atmospheric dry deposition of Cd, Pb and Zn and riverine discharge indicates that: (a) the metals deposited from the atmosphere to the Adriatic basin are a small fraction (2–5%) of those discharged by the Po and Adige rivers; (b) almost the same amounts of Cd, Pb and Zn are delivered to the Tyrrhenian Sea by the atmosphere and by the Arno and Tiber Rivers.     

Spatial distribution and geochemical baselines of major/trace elements in soils of Medak district,Andhra Pradesh,India

Regional-scale variations in soil geochemistry were investigated with special reference to differences among soil groups and lithology in an area of 9,699 km² in Medak district, Andhra Pradesh, India. The concentrations of 29 elements (major: Si, Al, Fe, Mn, Mg, Ca, Na, K, Ti, P and trace: As, Ba, Cd, Co, Cr, Cu, F, Mo, Ni, Pb, Rb, Se, Sr, Th, U, V, Y, Zn, Zr) in 878 soil samples collected (557-topsoil, 321-subsoil) at a sampling density of 1 site/17 km² from 557 sites representative of all the soil types present in studied area were determined, and their elemental composition are discussed. The baseline levels of these elements in soils are determined over different lithological units for the identification of anomalous values relative to these. For the first time, geochemical maps for Medak district are prepared on 1:50,000 scale and the lithogeochemical database generated provides information on the lateral and vertical distribution of elements in soil. The spatial variations in the distribution of elements reflect underlying geologic characteristics. Box-plots reveal that the concentration of most of the elements in soils were not strongly dependent on the soil group but the soil-geochemistry abruptly changes with the change in the soil parent materials indicating that the distribution of elements is mostly influenced by the bedrock lithology and other natural processes acting on them. For instance, the concentrations of Co, Cu, Fe, Mn, Ti, V and Zn are high in soils developed on basaltic terrain while the soils developed on granitic and gneissic terrain exhibit high elemental concentrations of K, Pb, Rb, Si, Th and Y. Alfisols had relatively high contents of elements while entisols had lower concentrations of most of the elements. The database can be used in the chemical characterisation of different geological units as well as applications in various environmental and agricultural fields. The results indicate that regional geology is an important determinant of soil geochemical baselines for soil pollution assessment and further emphasizes the importance of determining background levels locally. The defined baselines can be used to establish background values for future soil surveys.     

内蒙古甲乌拉火山岩型铅锌矿资源潜力评价

依据甲乌拉铅锌矿已有的地质、矿产、物探、化探等资料,建立了典型矿床预测模型,采用火山岩型预测方法类型对其深部及外围资源潜力进行了预测.预测深部Pb+Zn资源量656741t;外围Pb+Zn资源量2516870t.矿区深部及外围资源潜力较大.     

成都盆地平原区浅层土壤Cd、Pb、Zn分布特征及其成因初探

通过多目标地球化学调查在成都盆地平原区浅层土壤内发现呈面状分布的Cd、pb、Zn等元素高值区.为了研究它们的成因,应用多元统计方法分析了这些元素在不同景观区及不同环境介质中的分布特征及相关关系,利用参考元素对Cd、Pb、Zn的富集含量进行了定量估算.结果表明,平原区浅层土壤内Cd、Pb、Zn元素的分布明显不同于物源区及平原区深层土壤,在元素之间的典型相关关系及元素富集的分布特征上,均表现出明显的人为源特征.Cd、Pb、Zn元素的富集主要出现在平原区中部的城镇及农田区,与成都盆地浅层样地球化学图上的高值区一致.Cd、Pb、Zn元素的富集,是在自然背景的基础叠加了人为源含量,但尚未达到危害程度.     

江苏富硒土壤元素地球化学特征及主要来源

有关生态地球化学调查工程的成果应用已经受到高度关注。本文以江苏区域生态地球化学调查工程所获取的土壤、岩石等元素含量数据为基础,探讨了富硒土壤的分布特点、元素地球化学特征、物质来源与成因类型。研究结果显示：（1）全省富硒土壤的Se含量一般介于0.3~15 mg/kg,同时伴有S、TOC、Zn、Sb、Cd、Pb、As、Cr、Ni、Fe等相对富集;（2）富硒土壤可分为原岩风化残积型、煤矸石风化迁移型、湖相沉积型、粉煤灰型、污染叠加型、多金属矿化伴生型等6个成因类型,以产于苏南酸性土壤环境的原岩风化残积型富硒土壤利用价值最高,该类富硒土壤也是天然富硒农产品的主要产地;（3）富硒土壤物质来源具有多源复合性,表现为先天性物质来源（自然）、后天性物质来源（人为）及复合性物质来源（自然与人为叠加）等3种形式;（4）在先天性物质来源所形成的富硒土壤中,Se与S、TOC等呈显著正相关性,且Cd、Zn、Pb、As等未超标,富硒土壤厚度不受耕作层限制、深度可超过2 m。     

Multi-element geochemistry of sediments from the Pearl River system,China

Sediment samples were taken along the West, North, and East rivers of the Pearl River system at 28 locations in 1998, and a total of 49 elements were determined by ICP–AES, ICP–MS and INAA. The probability features of the datasets were studied, and the average concentrations of these elements in sediments of the three rivers were calculated. Significant differences in element concentrations among the three rivers were observed and the results were confirmed by statistical tests including analysis of variance (ANOVA), Kruskal–Wallis test, and t-test. Spatial distribution maps of element concentrations were produced using a geographical information system (GIS). The immobile trace elements (such as Sc, Ti, V, Cr, Mn, Fe, Co, and Ni) are enriched in the West River where limestone dominates the rock types in the watershed. Because of the strong weathering, immobile trace elements are enriched and reside in secondary minerals of the weathering products. All three rivers have high concentrations of rare earth elements (REEs) because of strong weathering, but relatively higher concentrations of REEs are observed in sediments of the East River where granite dominates the rock type. Granite contains high concentrations of REEs and the sediments have inherited this feature from their bedrock. Alkaline element (Li, Na, K, Rb, and Cs) concentrations are elevated in sediments of the East River, these may reside in granitic primary minerals. Relatively high concentrations of alkaline earth elements (Mg, Ca, Sr, and Ba) are observed in the West River, inherited from the limestone bedrock. High Pb and Bi concentrations are found in the North River and are caused by Pb mineralization and the discharge of a smelter in the upper reaches of the river. However, statistical tests did not indicate a significant difference between Pb concentrations in the North River and the other two rivers, which suggests that statistical results should be carefully used and explained.     

A geostatistical approach for mapping and uncertainty assessment of geogenic radon gas in soil in an area of southern Italy

Spatial distribution of concentrations of radon gas in the soil is important for defining high risk areas because geogenic radon is the major potential source of indoor radon concentrations regardless of the construction features of buildings. An area of southern Italy (Catanzaro-Lamezia plain) was surveyed to study the relationship between radon gas concentrations in the soil, geology and structural patterns. Moreover, the uncertainty associated with the mapping of geogenic radon in soil gas was assessed. Multi-Gaussian kriging was used to map the geogenic soil gas radon concentration, while conditional sequential Gaussian simulation was used to yield a series of stochastic images representing equally probable spatial distributions of soil radon across the study area. The stochastic images generated by the sequential Gaussian simulation were used to assess the uncertainty associated with the mapping of geogenic radon in the soil and they were combined to calculate the probability of exceeding a specified critical threshold that might cause concern for human health. The study showed that emanation of radon gas radon was also dependent on geological structure and lithology. The results have provided insight into the influence of basement geochemistry on the spatial distribution of radon levels at the soil/atmosphere interface and suggested that knowledge of the geology of the area may be helpful in understanding the distribution pattern of radon near the earth’s surface.     

豫西嵩县上庄坪铅锌银矿床地球化学特征及地质意义

上庄坪铅锌银矿床是新一轮国土资源大调查中在北秦岭二郎坪群发现的硫化物矿床。笔者通过对矿床矿石、容矿同岩、重晶石岩的微量、稀土元素地球化学特征分析和地质特征研究,探讨成矿构造环境、成矿物质来源及矿床成因问题。研究表明.矿石和容矿围岩稀土元素球粒陨石标准化组成模式均为右倾型.矿石与围岩在Cu-Pb-Zn判别图解中投点区域一致.矿石Zn/(Zn Pb)与冲绳海槽和上向黑矿矿石特征相似、与TAG和EPR13°N区硫化物存在差异.矿石具较高As、Sb和Pb与低Cu、Cd和Se元素特征.认为该矿床成矿元素来源于壳幔混合、但以壳源为主的围岩变(石英)角斑岩和变细碧岩。矿石稀土元素、微量元素地球化学特征、矿床地质特征及与热水沉积重晶石岩和硅质岩的紧密共生关系说明,上庄坪矿床是弧后盆地构造环境海底热液喷流成岩成矿作用的产物。重晶石岩、硅质岩、矿床纵向和横向分带是寻找和勘探该类矿床的重要标志和依据。     

Spatial distribution of metals in ground/surface waters in the Chandrapur district (Central India) and their plausible sources

This study addresses a framework to evaluate and map environmental hazard with reference to spatial distribution of major and trace metal contamination and its relationship with lithology in Chandrapur district of Maharashtra, India using geospatial, statistical and GIS tools. In all, 208 ground water and 35 surface water samples were collected using global positioning system (GPS) synoptically with satellite imagery IRS P6 LISS III and were analyzed in ICP-AES. Analytical results reflect the presence of major and trace metals in ground water in terms of % as Fe (48%), Mn (12%), Zn (9%), Al (8%), Pb (7%), Cu (6%), Ni (4%), Cd (3%) and Cr (3%) of the total average concentration. The contamination is attributed to weathering of rocks and also to mining activities. Similarly, surface water contribution of major and trace metals was found as Al (47.8%), Fe (42.8%), Mn (5.5%), Zn (2.3%), Pb (0.56%), Ni (0.42%), Cu (0.16%), Cr (0.16%) and Cd (0.10%) of the total average concentration. Ordinary kriging interpolation method was adopted to assess the spatial distribution of different major and trace metals in groundwater samples with their best model fit variogram Classical statistical method like principal component analysis (PCA) was carried out in order to establish correlation between spatial pattern of metal contamination and geology of the area in GIS environment. Various surface and subsurface aspects like landuse/land cover, structural features, hydrogeology, topography etc were also considered to ascertain their impact to supplement the inference of the study.     

母岩类型对土壤和沉积物镉背景的控制: 以贵州为例

镉是土壤和沉积物中最受关注的重金属污染物之一,合理确定其自然背景对于环境管理具有重要意义。然而,由于不同基岩中该元素含量差异很大,且在风化成壤过程中元素也可能发生富集或贫化,造成该元素具有很大的空间变异,甚至可以超出筛选值和管制值。本文从基岩-土壤地球化学元素迁移规律出发,以基岩类型较复杂、镉空间变异较大的贵州省为例,基于土壤和沉积物调查数据,建立基岩与土壤或沉积物中镉含量的对应关系,筛选合理的岩性类型端员和背景区域划分方法,为环境管理确定基础背景。研究结果显示,岩性类型是造成土壤镉空间变异的重要因素,石灰岩(排除白云岩)、玄武岩、辉绿岩和碳质页岩等是造成土壤高镉背景的重要岩石类型。相对母岩类型,岩石所在地层时代对土壤镉背景的影响不太明显。本文通过大量数据统计,给出了相对较纯的岩性发育土壤的镉背景值和变异区间,不纯岩性或地质单元发育土壤的镉背景值可能受多个岩性端员的影响。     

Trace metals in recharge and discharge ground waters at two sites at the Baltic coast of Sweden

The distribution and controls of trace elements (Cd, Cr, Cu, Ni, Pb, Zn and U) in shallow groundwater in discharge and recharge zones were analysed at two sites on the Baltic coast of Sweden; one granite-dominated and one with a significant addition of calcite. Although the study sites differ in overburden geochemistry and groundwater trace metal concentrations, which were well reflected in the general groundwater composition, the relative hydrochemical differences between recharge and discharge ground waters were similar at both sites, and temporally stable. The concentrations of Cd, Cu, Ni and U were higher in soil tubes in recharge areas, but Cr was higher in discharge zones. Also concentrations of HS, Fe, Mn and NH₄ were higher in discharge samples, which in combination with increased ³⁴S values provide strong evidence of a transition from oxidizing to more reducing conditions along the groundwater flow gradient. In terms of trace metals, this might mean either mobilisation due to dissolution of trace-metal carrying Fe(III) and Mn(IV) phases, or immobilisation caused by precipitation of discrete trace-metal sulfides or co-precipitation with Fe sulfides. The results from this study show that the latter is dominant in both the carbonate and granite environments for the metals Cd, Cu and Ni. Chromium concentrations were likely coupled to organic complexation and were higher in discharge groundwater, where DOC was also more abundant. As the concentration of several potentially toxic trace metals were found to differ between recharge and discharge areas, a climate driven change in hydrology might have a substantial impact on the distribution of these metals.     

应用壤中气汞量测量找金的效果——以湖南青京寨、三德堂金矿为例

湖南青京寨和三德堂分别为破碎带蚀变岩型，残积红土型金矿床。地表存在较厚的残（坡）积覆盖层，应用壤中气汞量测量法寻找隐伏含Au构造蚀变带及金矿体。区内气汞异常带及其峰值与隐伏含Au构造蚀变带及金矿体具有较好的对应性，利用这种对应性并结合区内地质，地球化学特征，施工适当的工程进行验证。在青京寨对6条气汞异常带进行工程揭露验证，各带均发现含Au蚀变带。三德常矿区圈定的金异异常与气汞异常基本一致。壤中气汞量测量法不仅适有于寻找中代温热液型金矿床，而且也适于寻找刚化残积型金矿床。     

The effect of traffic on levels,distribution and chemical partitioning of harmful metals in the street dust and surface soil from urban areas of Tehran,Iran

Due to the explosive industrialization and rapid expansion of the population in many parts of the world, heavy metals are released into the environment continuously and pose a great risk on human health. Street dust and surface soil samples from very heavy, heavy, medium and low traffic areas and a natural site in Tehran, Iran, were analyzed for some physicochemical features, total and chemical fractionating of selected metals (Zn, Al, Sr, Pb, Cu, Cr, Cd, Co, Ni and V) to investigate the influence of traffic on their mobility and accumulation in the environment. The pH, electrical conductivity (EC), carbonates and organic carbon contents were similar in soil and dust samples from the areas with same traffic. The traffic increases EC contents in dust/soil matrixes, but has no effect on concentrations of metals in soil samples. Rises in metal levels with traffic were found in dust samples. Moreover, the traffic increases the percentage of both acid-soluble and reducible fractions, which are related to Pb and Zn. The mobilization of Cu, Zn, Pb, Cr in dust samples was easier than in soil. The speciation of metals except Cd is mainly affected by physicochemical features in soil, though total metals affected the speciation in dust samples (except chromium and nickel).     

云南省三江地区区域地球化学特征及铜多金属矿找矿意义

根据云南省境内三江地区1∶20万地球化学调查资料,结合区域地质特征及成矿规律,对该区地球化学特征与矿产资源找矿潜力进行研讨,重点对与铜及铜多金属矿床有关的地球化学特征进行分析。本区主要成矿元素有Cu、Zn、Pb、Cd、Ag、As、Sb、Hg、Be、W、Sn、Bi等,其中铜矿相关元素Cu、Pb、Zn、Cd、Ag、As、Sb、Hg、Be等与岩浆活动和沉积热液改造有关。以本区三类典型铜矿床模型为依据,利用GIS技术进行预测,提出铜多金属成矿预测区14个,其中A类5个,B类6个及C类3个,为进一步矿产勘查工作提供参考。     

Specifics of the elemental composition of waters in environments with operating mining and ore-processing plants in the Kola North

The paper presents data on the specifics of the distributions of chemical elements in natural waters of the Kola North depending on the landscape–geochemical characteristics of the water catchment areas and aerotechnogenic pollution. The territory is subdivided into seven zones with different dominant rock types and typical landscapes. Lakes in the Kola region generally contain elevated concentrations of Cu, Ni, Co, Cr, V, Mo, U, Sb, Bi, Al, Fe, Mn, Sr, Li, Rb, Pb, Zn, Cd, La, and Ce. The waters of lakes in the influence zones of Cu–Ni mines are enriched in La, Ce, Sm, Gd, Pr, and Nd. In waterlogged landscapes, waters are enriched in certain trace elements because of their migration with humic acids. Technogenic acidic precipitation is proved to result in leaching of several elements, first of all Cd, Zn, and As (as well as other elements contained in rocks composing the water catchment areas) and their transfer into the waters.