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1.
In 1992, a monitoring survey has been started on the national scale in Slovenia using the epiphytic lichen Hypogymnia physodes (L.) Nyl. The primary aim has been to analyse lichens using the k0-based INAA method to obtain information about the levels of elements in the atmosphere and to identify significant pollution sources. Monte Carlo-Assisted Factor Analysis was applied to a data set of the 28 elements As, Ag, Ba, Br, Ce, Cd, Co, Cr, Cs, Fe, Ga, Hf, Hg, K, La, Mo, Na, Rb, Sb, Sc, Se, Sr, Sm, Tb, Th, U, W and Zn, which have been selected from the elements determined as the most important ones for the identification of pollution sources. A Monte Carlo approach has been used to give more insight into the uncertainties and significance levels of the factor analysis results. It has been found that concentration patterns in lichens yielded 9 factors (source types) which are presented and discussed in detail. The geographical patterns of the contributions of all factors are also shown.  相似文献   

2.
Summary Lichens as biomonitors and neutron activation analysis as analytical technique have been employed to evaluate the trace element atmospheric pollution in the metropolitan area of the city of Pavia (Northern Italy). Transplanted lichens (Parmelia sulcata and Usnea gr. hirta) and air particulate matter have been monthly collected and analyzed during the winter 2001-2002. INAA and ET-AAS have been used for the determination of 28 elements in air particulate matter and 25 elements in lichens. Trace metals concentrations as well as the corresponding enrichment factors were evaluated and compared.  相似文献   

3.
Trace element concentration patterns can be used for the identification of objects or materials. Early applications were related to the elucidation of identity or origin of objects. Recently, a number of applications have been reported of the use of trace element concentration patterns to recognize and identify components of mixtures of materials, mainly of environmental interest. In the present paper two examples are discussed of application of Target Transformation Factor Analysis to trace element concentration patterns, to identify sources of heavy metal air pollution. The materials studied are air particulate matter and epiphytic lichens used as biological accumulator.  相似文献   

4.
The objective of this paper was to assess the air pollution and the main sources of Air Particulate Matter in the Setúbal urban/industrial area, Portugal. PM2.5 and PM2.5?C10 were sampled in Nuclepore filters and lichens transplants were exposed during 9?months. The levels of elements in these two matrixes were measured by INAA and PIXE. A large data base was created and source apportionment was performed by using Principal Component Analysis. The results showed that the main sources of fine particles were anthropogenic and were related with traffic and local industry. There was an important contribution of natural sources, mainly for the coarse fraction, associated with the sea and the soil. Lichens characterization and mapping showed that different site-specific characteristics controlled the spatial distribution of different elements. This study showed that biomonitoring is an effective complementary method to traditional sampling systems.  相似文献   

5.
Capabilities of black poplar-tree (Populus nigra L.) bark as a biomonitor of atmospheric air pollution by chemical elements were tested against epiphytic lichens Xanthoria parietina (L.) and Physcia adscendens (Fr.). Concentrations of 40 macro and trace elements were determined using epicadmium and instrumental NAA. The data obtained were processed using non-parametric tests. A good correlation was found between concentrations of majority of elements in bark and lichens. On the accumulation capability bark turned out to be competitive with both lichens examined. The main inorganic components of black poplar-tree bark were revealed. A substrate influence on the concentrations of some elements in epiphytic lichens was established. An optimized procedure of bark pre-irradiation treatment was suggested.  相似文献   

6.
A biomonitoring study, using transplanted lichens Flavoparmelia caperata, was conducted to assess the indoor air quality in primary schools in urban (Lisbon) and rural (Ponte de Sor) Portuguese sites. The lichens exposure period occurred between April and June 2010 and two types of environments of the primary schools were studied: classrooms and outdoor/courtyard. Afterwards, the lichen samples were processed and analyzed by instrumental neutron activation analysis (INAA) to assess a total of 20 chemical elements. Accumulated elements in the exposed lichens were assessed and enrichment factors (EF) were determined. Indoor and outdoor biomonitoring results were compared to evaluate how biomonitors (as lichens) react at indoor environments and to assess the type of pollutants that are prevalent in those environments.  相似文献   

7.
A project has been undertaken to carry out a long term study on atmospheric air pollution in Chile using biomonitors. Samples of different species of lichens were collected in clean areas (native forest), analyzed and transplanted to the Santiago Metropolitan Area. In addition, samples of Tillandsia recurvata were collected in the Metropolitan Area for comparison purposes. The preparation of the samples was done under controlled, cryogenic conditions and analyzed by neutron activation analysis and solid sampling atomic absorption spectrometry. As part of the routine QA/QC procedures, the analytical laboratories, have participated in intercomparison runs organized by the IAEA for the determination of trace and minor elements in two lichens samples. The present paper describes the activities carried out within the framework of this project. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
Biomonitoring of PAH air pollution using lichens was carried out. Sixteen PAHs were studied in 11 locations along the valley of Caracas (Venezuela). The results of this work indicate that 14 of the 16 analysed PAHs were highly accumulated into the lichen thalli of Pyxine coralligera Malme. PAH levels in the samples revealed that the several volatile PAHs (naphthalene, acenaphtylene, acenaphtene, and fluoranthene) have the highest levels in the majority of the studied locations. The fluoranthene/pyrene and phenantrene/antracene ratios suggested that the major sources of PAHs are anthropogenic, mainly associated with gasoline and diesel combustion (pyrolytic) and unburnt oil derivates (petrogenic). The total PAH concentrations obtained in the present study were in the range of 0.24 to 9.08?µg/g, similar to those reported by other works in European and Asian cities.  相似文献   

9.
Summary An epiphytic lichen (Physcia alba sp.) grown over Roystonea regia tree was used as biomonitor of air quality in the Havana City west side. During the survey, 81 sampling sites were selected according to traffic and industry conditions. The concentration for 14 elements (Mg, Al, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Cd and Pb) was determined by flame atomic absorption spectrometry (FAAS) and anodic stripping voltammetry (ASV). Contents of Cu, Zn, Cd and Pb obtained by both techniques were compared. Several biological reference materials (RM's) were analyzed in order to assure the quality of analytical results. Some pollution sources were identified using principal component analysis. A total of 5 factors were achieved, of which 4 could be interpreted in terms of anthropogenic pollution sources. However, the expected correlation between traffic influence and lead concentration in lichen could not be demonstrated. The factor values patterns are presented.  相似文献   

10.
The distribution of the chemical element during weathering of trachyandesite in S. Miguel Island (Azores, Portugal), and in mosses and lichens growing on these rocks, was studied using instrumental neutron activation analysis. A general enrichment of rare earth elements (REEs), a Ce positive anomaly (partial oxidation after primary apatite dissolution) and a Eu negative anomaly (Eu2+ in plagioclases/clay minerals) are observed with increasing weathering. Mosses and lichens are Ce and Eu depleted, indicating that the main REE uptake is done via absorption from REE3+ secondary phosphates, probably together with P (essential nutrient). Zn, Br and Sb show higher enrichment factors in lichens and mosses.  相似文献   

11.
Instrumental Neutron Activation Analysis (INAA) has been applied for the determination of 8 rare earth elements (REE) in sediment cores collected from stations of polluted and unpolluted areas of Northern Saronikos Gulf. The REE determined in cores are: La, Ce, Sm, Eu, Tb, Dy, Yb and Lu. Higher levels of all REE were found in the cores from polluted areas of N. Saronikos Gulf as compared with those from unpolluted areas. Different vertical profiles of REE were found in the cores from two stations of polluted areas which indicate that REE may distinguish pollution sources.  相似文献   

12.
Summary As part of an air pollution monitoring study, airborne particulate matter (PM2/PM10-2) samples were collected from 2000 to 2003 at two sampling sites in an urban region, Daejeon, the middle of Korea. Mass concentrations of both fine and coarse fractions and that of the black carbon in the fine particles were measured using the Gent stacked filter unit sampler and the smoke stain reflectometer, respectively. In the collected samples the concentrations of 24 elements were analyzed using instrumental neutron activation analysis. Monitored data were investigated for their temporal trends under different environmental conditions and their seasonal correlation patterns. Crustal enrichment factors were also estimated to establish the contribution between anthropogenic and crustal origin. Patterns for airborne particle matter (APM) and elemental concentrations, seasonal variation of some marker elements were investigated. The results can be applied for the investigation of further air pollution sources and for the evaluation of air quality.  相似文献   

13.
Summary Twenty six elements was studied preliminary in the superficial sediments of Havana Bay using gamma activation analysis by the electron accelerator microtron MT-25 at the Flerov Laboratory of Nuclear Reactions, JINR. Samples from five zones of Havana Bay including the three coves were analyzed. The obtained results show a close relation between the concentration levels of the studied elements and the pollution sources. Some elements (As, Ba, Ni, Pb, Cu, Zn, Fe, Cr, Mn) have high concentration levels compared to the values for other environmental marine sediments reported in the literature.  相似文献   

14.
有色金属矿产资源采选冶活动造成的土壤重金属污染已成为严重的环境问题。采用电感耦合等离子体质谱法和光谱法测定某冶炼厂周边不同区域内土壤中重金属Cu、Pb、Zn、As、Ni、Cr、Cd、Hg元素含量,采用Kriging空间插值方法对重金属空间分布特征进行分析,采用内梅罗指数法对其污染状况进行评价,采用多元统计分析对重金属元素的污染源进行分析。结果表明,研究区土壤采样点80%处于污染状态,且以重度污染为主,污染比较严重的区域受风向影响在冶炼厂的西部和南部方向,污染严重的重金属元素为Cu、Pb、Cd、Zn和As,土壤中各重金属元素的污染源除来自于冶炼厂外,Zn-Cd-PbCu-As、Ni-Cr、Hg分别还受到机动车辆排放、自然因素、燃煤及农药使用的影响。  相似文献   

15.
In this work, we compare the concentrations of trace elements for fourty samples of lichens, mosses and tree barks used as biomonitors in an air pollution biomonitoring study in Morocco. This comparison concerns six types of biomonitors: the lichens Xanthoria parietina, Parmelia sulcata and Evernia prunastri; the moss Hylocomium splendens and barks of cedar and cork oak. The complementarity of three analytical methods was used in order to increase the number of determined elements. These techniques are: 14 MeV neutron activation analysis, thermal neutron activation analysis using the k 0-quasi-absolute method and X-ray fluorescence analysis. The results enabled us to compare the element accumulation sensitivity for the six biomonitors used and to study the local concentration variations versus biomonitors sizes and the height above ground of their collecting point.  相似文献   

16.
The atmospheric pollution of São Paulo city is a serious problem due to the expansion of industrial area, increasing number of vehicles and population density. This work presents results obtained in the analysis of lichens collected in different sites of São Paulo city and in non-polluted areas of Atlantic Forest. Concentrations of twenty elements were determined in Canoparmelia texana species and comparisons were made between the results obtained in lichens from different sites. High concentrations of the elements As, Ba, Cd, Co, Cr, Fe, La, Mn, Sb and Zn were found for samples collected in sites located near industries and petrochemical plant. Br and Sb concentrations were also high in lichens from sites affected by vehicular emissions.  相似文献   

17.
Instrumental neutron activation analysis was used for the analysis of 25 trace elements in airborne particulate matter (PM) for air pollution monitoring. For the collection of air samples, the Gent stacked filter unit low volume sampler and two types of Nuclepore polycarbonate filters were employed. Samples were collected at selected sampling dates in suburban and industrial regions of Daejon city in the Republic of Korea. Mass concentrations and black carbon of PM were measured, and enrichment factors were calculated. The results were used to describe the emission sources and their correlation patterns.  相似文献   

18.
The process of urbanization and industrialization during las two decades has resulted in increased level of air pollution causing hazards to human health. Instrumental neutron activation analysis (INAA) using short and long term irradiation has been employed for the determination of more than 30 elements in suspended particulate matter (SPM) from six metropolitan cities and three industrial surroundings. A comparison of mean elemental contents in dust particulates from commercial, industrial and residential zones of Delhi, Calcutta, Madras, Cochin, Bombay and Nagpur cities has shown wide variation in toxic pollutant (As, Br, Cr, Cu, Hg and Sb) concentrations. Coastal areas have shown higher concentrations of Na, K, Cl and Br. Highly industrialized Bombay showed highest levels of Br, Cl, Cr, Fe, Mg, P, Rb and Sc. Mean elemental contents in fugitive and ambient dust of a cement factory and thermal power station (both in central India) are widely different. SPM levels in fugitive dust of the two industrial surroundings are higher by an order of magnitude compared to ambient air. Analysis of ambient air dust from a paper mill showed highest concentrations of Hg, Sb and Zn. Elemental data have been compared with those of Urban Particulate Matter (SRM 1648), Coal Fly Ash (SRM 1633a) and Vehicle Exhaust Particulate (NIES No. 8) which were analysed for quality control. An attempt has been made to attribute the elemental contents to possible sources of origin.  相似文献   

19.
Chlorine-36 (half life 3.01 × 105 year), a beta emitter, is produced naturally but its presence has been enhanced by atmospheric weapons testing and other nuclear activities. Iodine-129 has a half life of 1.57 × 107 years and is also produced by nuclear activities, in particular fuel reprocessing. Many elements have a long biological half-life in lichens, which were thus investigated so as to assess their suitability for 36Cl and 129I monitoring. Lichens sampled between 1998 and 2008 were analysed for total chlorine, and selected samples were processed for 36Cl measurement using Accelerator Mass Spectrometry (AMS); 129I was analyzed by gamma spectrometry. Different aspects are discussed: long-term storage in lichens versus environmental mobility, levels in samples collected near a reprocessing facility, and potential for spatial and temporal monitoring.  相似文献   

20.
The levels of twelve elements most of which are either considered essential to plant growth or have been detected in air filter samples in an air pollution survey, have been monitored in three transverse sections of trees, two elms (ring porous trees) and one cedar (a conifer). Two dimensional distributions of these elements around the tree rings of the section and radially from ring to ring, have been obtained to see if tree rings can be analysed for use as a record of historical pollution.  相似文献   

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