首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
The chemical composition of 73 surface soil samples collected at the city of Antalya were analyzed for major, minor and trace elements to assess distribution of soil pollution, due to deposition of pollution-derived particles from the atmosphere. Comparison with data from rural area and distribution maps demonstrated that the composition of soil by metals is not significantly modified by anthropogenic activities in most of the city and its surroundings. In these areas, observed concentrations can be largely accounted for by occurrence of elements in aluminasilicate matrix of soil. However, soil composition is altered substantially close to major industries and at the settlement districts. In such limited areas, concentrations of anthropogenic elements such as Cd, Pb, Zn, Cu and Cr are factors of 20-50 higher than their concentrations in unperturbed soil. Factor analysis revealed three groups of elements that differ in their distributions. One of these components is unperturbed soil component, which is distributed uniformly in the study area; the second one is polluted soil, which is mostly confined to settlement areas and around industries; and the third is a mixed marine and motor vehicle impacted soil component, which occurred at the coastal parts of the city.  相似文献   

2.
Sediment cores were taken from six sites across the UK. Apart from Banbury Reservoir in London, all the other sites are relatively remote lakes. Trace elements Pb, Zn, Cu, Cd, Cr, Ni, Sn, As and V, major elements such as Fe, Mn, Ti and Al were analysed, and organic content measured as loss-on-ignition was determined in all of these cores. The result shows that these relatively remote sites have experienced enhanced atmospheric deposition of anthropogenically derived trace elements for over 100 years, and the contamination might start before industrialisation. Trace metal contamination remains the highest level at Banbury Reservoir showing "pollution source" influence. Despite the considerable reduction in atmospheric deposition in recent years, although some of the element concentrations in the surface sediments have declined, they are still much higher than their natural background values. In these sites, trace element pollution records have been influenced by many different factors. Redox condition could affect As distribution in the sediments. Sediment matrix could also affect trace element pollution signal. Apart from direct atmospheric deposition, the distributions of trace elements in the sediments have been affected by forestry activities and catchment erosion, and more contaminated soil in-wash could increase sediment pollution whilst less contaminated soil could dilute sediment pollution. In some sites, data suggest that catchment in-wash is an important source of elements for the lakes.  相似文献   

3.
This report presents the results of PAH, phenol, and selected trace element (Cd, Cu, Hg, Pb, S, and Zn) determinations on detailed soil profiles and associated plant bioindicators (including lichen Hypogymnia physodes, moss Hylocomium splendens, pine Pinus sylvetris) from the three most representative habitats in the Holy Cross Mts, south-central Poland. This study is only part of a larger ongoing environmental study that includes complex sulfur isotope and element determinations in three national parks in N, central and S parts of Poland. The highest concentrations of PAHs (1887 ppb) and numerous trace elements are found in the organic horizon-O and humic horizon-A of each soil type. Different plant species and their individual tissues reveal considerable variability in the concentration of PAHs, phenols and elements examined. Most of the H. physodes thalli also reveal higher concentrations of individual hydrocarbons and some elements (including S and Zn) than their host bark. The highest concentration levels of phenols (1217 ppb) are noted in the 1-year pine needles. Most of the PAHs and elements examined seem to be of anthropogenic origin. The only exception is the distribution pattern of elements in southwestern part of the study area, which is linked to the local bedrock geochemical anomaly. The results of this study indicate that the content of PAHs, Cd, Cu, Hg, Pb, S and Zn in the soils and plant bioindicators examined has not changed considerably since 1998.  相似文献   

4.
Uptake of uranium and thorium by native and cultivated plants   总被引:2,自引:0,他引:2  
Large part of available literature on biogeochemistry of uranium and thorium refers to the studies performed either in highly contaminated areas or in nutrient solutions that have been artificially ‘spiked’ with radionuclides. Effects of background levels of natural radioactivity on soil-grown plants have not been studied to the same extent. In this paper, we summarised results of greenhouse and field experiments performed by the author from 2000 to 2006. We examined some of the factors affecting transfer of U and Th from soil to plants, differences in uptake of these radionuclides by different plants, relationships between U and Th in soil and in plants, and temporal variations of U and Th in different plant species. Concentrations of radionuclides (critical point for experimental studies on biogeochemistry of U and Th - rare trace elements in non-contaminated regions) and essential plant nutrients and trace elements were determined by instrumental neutron activation analysis.  相似文献   

5.
The distribution of major and trace elements was systematically investigated by use of energy dispersive X-ray fluorescence spectrometry (EDXRF) on a former horticultural soil. The purpose of the study was to combine mapping of soil element concentration levels with multivariate statistics for characterisation of soil metal pollution in relation to previous and present land use. A 1-ha study site was chosen from a former horticulture where a previous preliminary survey indicated increased concentration levels of toxic elements. The soil was sampled from the top 20 cm of the soil surface in a 10 x 10-m grid-like pattern covering the 1-ha study area. In addition, three soil profiles were studied. The elemental composition of the soil samples was investigated by EDXRF while the composition of aqueous soil extracts was determined by total reflection X-ray fluorescence spectrometry (TXRF). Based on mapping and multivariate statistically analysis of the data obtained by EDXRF, most elements were found in almost constant concentration levels in the top soil throughout the investigated site. However, the contents of the toxic elements Zn, Cu, As, and Pb were found to vary significantly within the area. Hence, the samples with high accumulations of As also contained relatively high amounts of Zn, Cu, and Pb, which indicates that toxic-element-containing pesticides have been applied to the soil surface in the area of the former green houses at the study site. The Pb/As mass ratio in the soil indicates that PbHAsO3 was the preferential lead arsenate used for pest management at the investigated site, while Cu as Bordeaux liquid (CuSO4) and Zn were applied to minimize the leaf damaging effect from the former compounds. Calculations indicated that As annually was applied to the soil in the former greenhouses in doses up to 4 kg As/ha while Pb had been annually applied in doses up to 12 kg Pb/ha. The enrichment of Zn, Cu, As and Pb was greatest in the top 20 cm of the soil and no anthropogenic enrichment of these elements occurred below a depth of 50 cm, indicating that the toxic elements are rather immobile in this soil. The results of this investigation suggest that EDXRF used in combination with multivariate statistics is a strong tool for multi-element mapping of elemental contents, sources and mobility in the terrestrial environment.  相似文献   

6.
洞庭湖退田还湖区畜牧业资源与环境评估   总被引:2,自引:1,他引:1  
以洞庭湖流域3个选择畜牧业为替代产业的退田还湖示范堤垸为例,以氟、铬、镉、铅、汞和砷为主要检测指标,参照国家标准,分别对示范堤垸内与畜牧业密切相关的水、土壤与饲草饲料的质量进行了评估。结果表明,示范堤垸水环境化学指标除了大肠杆菌群落外,其余基本达到了无公害和绿色食品卫生标准中关于农田灌溉用水和养殖用水的规定;土壤中铬、镉、铅、汞和砷与氟的背景值均低于无公害和绿色食品标准规定的产地土壤环境指标;大部分饲料、饲草原料中氟、铬、镉、铅、汞和砷含量符合无公害或绿色食品卫生标准。示范堤垸水、土和饲料资源的良好环境背景状况为畜牧业向绿色或有机畜牧业方向发展奠定了自然条件与资源的基础。  相似文献   

7.
In the industrialized urban area of Avilés (Spain), pooled soil samples from grassland sites were taken after careful sampling design and then investigated for their content of trace elements. A combination of statistic and geostatistic techniques proved to be a reliable tool in the interpretation of the analytical results. Geochemical groups and areas influenced mainly by anthropogenic activities were distinguished by means of classic multivariate methods (factor analysis and cluster analysis) and innovative geostatistical tools (Fourier spectral analysis). The constitution of the groups is supported by the linked results of methods sequentially distributed in order to extract as much information as possible from the original data.  相似文献   

8.
Proton induced X-ray emission spectroscopy has been successfully used to measure variations in relative and absolute trace element concentration levels in tree rings. Valuable information on past concentration levels, stored in the tree rings have been obtained. Peaks associated with 15 elements have been identified in all X-ray spectra. Variations of trace elements levels in the tree rings reflect the variations in their availability from the environment.  相似文献   

9.
Results of a recent intercomparison on the determination of trace elements in simulated air filter samples are reported. A large scatter of results is obtained for some elements and systematic differences between laboratories are observed. The performance of different methods, in particular neutron activation analysis and atomic absorption spectrophotometry, used by the various laboratories is discussed (air filter analysis; intercomparison; trace elements; control charts).  相似文献   

10.
Sediment samples were collected during the research vessel Umitaka-Maru cruises in the Gulf region from 15–16 December 1993 and 15–27 December 1994, from 19 and 24 locations, respectively. These samples were subjected to trace metal analysis to determine the 1991 Gulf War oil spill environmental impact in the area. The samples investigated are texturally classified into two main sediment classes: sand and mud. The total concentrations of lead, nickel, and vanadium found in the sediments from individual stations were investigated. The differences in trace metal concentrations reflect the variation in the overall composition of their host sediments. To better appraise the trace element composition of their host sediments and to determine the factors governing the trace metal distribution, the data were sub-divided into five groups among 1993 collections and seven groups during 1994. The concentration ranges of all three metals, lead (0.2–4.85), nickel (4.90–86.00), and vanadium (2.00–38.00) varied in different stations among the groups. The partitioning of trace elements between the detrial and non-detrital fractions of the sediments shows that: 1) The high concentrations of elements in mud is coupled with the increase in the detrital fraction; 2) In muddy sand sediments, nickel is bonded to the structural lattice of detrital minerals, whereas vanadium and lead held in the environmentally mobile fraction; and, 3) In sandy mud sediments, Ni is found in the detrital fraction, whereas V to slightly less extent and Pb show their non-detrital nature. The data were compared with unpolluted sediments throughout the ROPME Sea and worldwide, so the effect of anthropogenic enrichment upon the absolute concentration of the elements is minimal.  相似文献   

11.
The antagonistic effects of supplementation of Zn and Se to the soil on vegetables were studied in this work. In the pot experiment, Se (Se4+) and Zn (Zn2+) were applied, respectively, to the soil, in which the Chinese cabbage (Brassica rapa) and the lettuce (Lactuca sativa L.) were planted. As a result, Se and Zn were enriched evidently in the two vegetables. The contents of Pb and Cd in the two vegetables were decreased markedly while contents of some healthy mineral elements, like Mn and Mg, were increased to some extent when Se and Zn were applied. The antagonism of Se and Zn against Pb and Cd in plants was suggested. The farmland experiment on the lettuce was conducted to explore further the effect of supplementation of Zn and Se under the actual field conditions. Result came out to be that the enrichment of Zn and Se restrained the accumulation of Pb and Cd in the lettuce remarkably, as well as enhanced the absorption of some other nutritional elements, like Fe, Mn, Cu, Ca and Mg. Therefore, application of Se and Zn was proved to be an effective and feasible method to improve trace elements nutrition in the vegetables.  相似文献   

12.
The use of geothermal energy for electrical generation and a variety of other purposes requires the handling and disposal of large volumes of geothermal fluids. These fluids contain constituents such as dissolved ammonia, hydrogen sulfide gas, and trace elements. Facilities in the United States are not expected to routinely discharge large volumes of toxic geothermal fluids. However, chronic effects on aquatic ecosystems are possible at concentrations where acute toxicity would be neither expected nor observed. Also, some trace elements may accumulate to hazardous levels in ecosystems, even when released at nontoxic concentrations.  相似文献   

13.
Soil plays a central role in food safety as it determines the possible composition of food and feed at the root of the food chain. However, the quality of soil resources as defined by their potential impact on human health by propagation of harmful elements through the food chain has been poorly studied in Europe due to the lack of data of adequate detail and reliability. The European Union's first harmonized topsoil sampling and coherent analytical procedure produced trace element measurements from approximately 22,000 locations. This unique collection of information enables a reliable overview of the concentration of heavy metals, also referred to as metal(loid)s including As, Cd, Cr, Cu, Hg, Pb, Zn, Sb. Co, and Ni. In this article we propose that in some cases (e.g. Hg and Cd) the high concentrations of soil heavy metal attributed to human activity can be detected at a regional level. While the immense majority of European agricultural land can be considered adequately safe for food production, an estimated 6.24% or 137,000 km2 needs local assessment and eventual remediation action.  相似文献   

14.
采用Pearson相关性分析、Spearman相关性分析、偏相关性分析、方差分析和地统计学方法,对江西省耕地表层(0~20 cm)土壤有效态B、Cu、Fe、Mn和Zn等5种微量元素含量空间变异特征及其影响因素进行研究。结果表明:研究区土壤有效态B、Cu、Fe、Mn和Zn总体处于中等以上水平,B表现为强变异性,其他有效态元素均呈中等变异性。空间结构方面,B、Cu、Fe、Mn和Zn的块金效应值依次为15.68%、12.09%、87.63%、77.98%和25.27%,表明B和Cu具有强烈的空间相关性,Zn呈中等空间相关性,而Fe和Mn空间相关性较弱。空间分布方面,土壤有效B含量表现出“两边低、中间高”的空间分布趋势,Fe、Cu、Zn呈现出较为平滑的空间分布格局,Mn在空间分布上并无明显规律。Pearson相关性分析和偏相关性分析表明5种微量元素之间存在一定的耦合关系但并无直接相关性。Spearman相关性分析和方差分析结果表明,高程、坡度、pH、有机质、全氮、成土母质、地貌类型、土壤类型、灌溉能力、秸秆还田方式和常年耕作制度对5种微量元素含量的空间变异影响显著(P<0.05)。结果可为江西省测土配方施肥卡制定与耕地资源利用与管理及优质高产种植提供可靠参考依据。 关键词: 江西省;微量元素;空间变异;相关性分析;偏相关性分析;影响因素  相似文献   

15.
The Pumicestone region is a unique catchment in northern Moreton Bay, southeast Queensland. The region supports a wide range of land-use activities as well as attractions such as nature conservation areas. One environmental aspect that has not previously been addressed in this area is the occurrence of minor and trace metals in estuarine sediments associated with the main estuaries of the region. The trace metals included in this investigation are: vanadium, chromium, molybdenum, cobalt, nickel, copper, zinc, cadmium, lead and arsenic. To determine and evaluate the occurrence and distribution of metals in the area, several components have been analysed: bedrock material, pre-industrial settings, recent estuarine sediments, soils of estuarine origin and mangrove pneumatophores. The 40 sites chosen for sediment and soil samples cover a variety of estuarine settings and represent a range of natural conditions in terms of channel and bank morphology, tidal energy, vegetation cover, relationship to bedrock, water salinity and land disturbance. The chemical, mineralogical and statistical analyses employed in this study enabled (a) establishment of background values for the area, (b) determination of relationships between metals and (c) identification of sites with anomalous metal concentrations. All the metals found in the sediments of the area are sourced from the geological bedrock. The dominant trace elements identified in sediments are Zn, V and Cr. The remaining metals are highly variable spatially. All trace metals are controlled by the presence of Fe and Mn oxides, and by the grainsize of the sediment. Typically, fine-grained Fe-rich materials tend to adsorb more trace metals than sandy sediments. In soils that have developed from estuarine muds, some metals such as Cr, Mo, Pb and As tend to be in larger quantities than in the estuarine counterparts. Some of the elements, which occur in significant amounts in the sediment, have been detected in mangrove tissue (Avicenniamarina) such as V, Cr, Zn, Fe and Mn. Of particular note is Cu, which is present in mangrove tissue in quantities many times exceeding the sediment concentration. The comparative analysis of pre-industrial settings and recent sediments and soils highlighted some areas of metal enrichment such as acid-affected sites where oxidation of pyrite has mobilised metals from sediments; these metals are then redistributed in Fe-rich surficial layers. Disturbed banks within the estuaries are also likely to have low levels of metal enrichment due to boating activities.  相似文献   

16.
Urban air particulate matter (APM) was collected at two sampling sites in the city of Lodz, Poland in March, May and July 2001. The concentrations of several trace elements (TEs) as well as heavy metals were determined by neutron activation analysis (NAA). It was found that for many elements, the contribution of the blank values arising from the filtering material is very high, especially for glass fiber filters. The results obtained for Lodz were compared to those obtained for Milan, Italy. The data of Lodz are, in general, lower than those found in Milan downtown in the winter season. The influence of three coal-fired power plants located within the city of Lodz on the concentration of trace elements in APM was also considered.  相似文献   

17.
Specimens of the mussel Bathymodiolus azoricus were collected from Menez Gwen, a relatively shallow (850 m) hydrothermal vent field on the Mid-Atlantic Ridge. Each bivalve shell (n = 21) was individually cleaned by selective chemical. The residual crystal matrix of each shell was individually analysed for the concentrations of the minor elements magnesium and strontium and the trace elements iron, manganese, copper and zinc. The chemical composition of the crystal matrix is unusual. B. azoricus is identified as a species having one of the most strontium impoverished shells amongst the marine molluscs. For a bimineral species the magnesium concentration is also extraordinary low. Despite originating from a trace metal rich environment; the metal concentrations in the shells were exceptionally low. Mean concentrations of iron, manganese, copper and zinc were 20.6, 3.7, 0.6 and 9.4 microg g(-1) respectively. Minor and trace element concentrations exhibited a marked intra-population variability. Copper concentrations increased and iron and zinc concentrations decreased with increasing shell weight. Due to its insensitivity to the high environmental levels of trace elements and the variability in intra-population concentrations induced by shell weight the crystal matrix of the shell of B. azoricus has little potential for use in environmental trace metal monitoring in areas contiguous to deep-sea hydrothermal vents.  相似文献   

18.
利用多元统计方法研究了湖北梁子湖水体及底泥中12种微量元素和重金属(As,Ba,Co,Cr,Cu,Hg,Mn,Ni,Pb,Sb,Sr和Zn)的含量及空间格局,并通过饮用水及地表水质量标准及地质累积指数评价梁子湖水质及底泥状况。结果表明:梁子湖的水体质量较好,仅Cu是潜在污染物质;对湖泊底质而言,As是主要污染物质,Cu、Pb和Zn处在轻微的污染状态。空间格局显示:受人类活动的影响,湖泊水体中的重金属分布有较强的区域性,最大值出现在人类活动相对集中的梁子岛附近;在湖泊底泥中由于地质背景一致性而差别不大。相关分析表明,较之湖泊水体,湖泊底泥中的重金属元素的关系更密切,强相关性说明它们可能有共同的来源。未来研究应结合湖泊中大型水生植物及鱼类的重金属含量更全面考虑生态学效应,为恢复湖泊生态环境的管理提供重要参考。  相似文献   

19.
《Environment international》1999,25(2-3):325-334
In the dystrophic Lake Skjervatjern, located at the west coast of Norway, periods with high precipitation coincide with an increase in the concentrations of natural organic matter (NOM) and several trace elements. The lake has no visual inlets, and, during high flow periods, a major part of the drainage follows macropores, entering the lake 10–40 cm below the surface. Water from the lake and the macropores were fractionated according to size by means of a hollow fiber ultra-filtration technique, during two periods with high precipitation. In the macropores, the high molecular weight form of NOM (nominal molecular cut off > 10 kDa) appears to be an important transporting agent for several trace elements that strongly interact with NOM (e.g., Fe, Al, Pb, Sm, La, Ce, and Eu). In contrast, anionic (V and As) and acid sensitive (Mn and Cs) elements were, generally, at a low molecular weight form (nominal molecular cut off < 3 kDa). The latter showed similar or lower concentrations in the macropores compared to the lake water, and NOM were apparently of small importance as a carrier for V, As, Mn, and Cs. Differences in concentration and size distribution of trace elements between the macropores and the lake basins indicate that parts of NOM and associated trace elements that enter the lake in a high molecular weight form, undergo aggregation and gravitational settling and thereby become a part of the lake sediments.  相似文献   

20.
Temporal changes in the amounts of trace elements (As, Co, Cu, Mn, Ni, Pb, and Zn) and their correlations with temporal changes in charcoal abundance in age-dated sediments collected from Lake Thompson in Patagonia, Chile, attest to the substantial pyrogenic remobilization of contaminants that occurred in Patagonia during the mid-1900s. This remobilization was concurrent with the extensive slash and burn period in the region during that period. The changes in concentrations of Co, Cu, and Ni in relation to charcoal abundance in the lacustrine sediments over time were small compared to those of As, Mn, Pb, and Zn. However, the relatively low enrichment factors of all those trace elements, normalized to Fe, indicate that they were predominantly derived from local, natural sources impacted by fires rather than industrial sources. The primarily local source of Pb in the sediments was corroborated by the temporal consistency of its isotopic ratios (206Pb/207Pb:208Pb/206Pb), which were similar to previously reported values for natural lead in Central and Southern Chile. However, the pyrogenic remobilization of both natural and industrial trace elements by forest fires in Chile and elsewhere is expected to rise as a consequence of climate change, which is projected to increase both the frequency and intensity of forest fires on a global scale.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号