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1.
The joint application of electromagnetic techniques for near-surface exploration is a useful tool for soil pollution monitoring and can also contribute towards describing the spatial distribution of pollutants. The results of a geophysical field survey that was carried out for characterizing the heavy metal and waste disposal soil pollution phenomena in the industrial area of Val Basento (Basilicata region, Southern Italy) are presented here. First, topsoil magnetic susceptibility measurements have been carried out for defining the spatial distribution of superficial pollution phenomena in the investigated area. Second, detailed and integrated measurements based on a high-resolution magnetic mapping and ground probing radar (GPR) profiling have been applied to investigate the subsurface in two industrial areas located in more polluted sites that were identified during the first phase. Our monitoring strategy discloses the way to rapidly define the zone characterized by high pollution levels deriving from chemical industries and traffic emissions and to obtain the way information about the presence of local buried sources of contamination.  相似文献   

2.
《Applied Geochemistry》2001,16(11-12):1361-1368
Due to rapid urbanisation and scarcity of land, most of the urban parks and recreational areas in Hong Kong are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. An extensive soil survey was conducted in urban parks of Hong Kong to study the current conditions of heavy metals contamination in soils. Soil samples and associated street dusts were collected from more than 60 parks and public amenity areas in old urban districts, industrial areas and New Towns of the territory. Soils were also sampled in the remote country parks to establish the baseline conditions. The total concentrations of heavy metals and major elements in the samples were determined. The results indicate that urban soils in Hong Kong have elevated concentrations of Cd, Cu, Pb and Zn. The parks with high metal concentrations are located in old urban commercial districts and industrial areas, indicating that the major contamination sources in these soils are traffic emissions and industrial activities. In addition, the application of Cd containing phosphate fertilizers may be an important source of Cd in urban park soils. The street dusts have highly elevated Zn concentration, particularly along the main trunk roads. The high Zn content in the street dusts may come from traffic sources, especially vehicle tyres. Selective soil and road dust samples were also analysed for potential chemical speciation by a sequential chemical extraction method. The chemical partitioning results show that Pb and Zn are mainly in the carbonate/adsorbed and Fe–Mn oxide phases, while Cu is largely associated with the organic and sulphide fractions. The high exchangeable Cd in urban soils and high concentration of Zn in street dusts need further investigation for their ecological and health implications.  相似文献   

3.
The assessment of anthropogenic impact in the urban environment can be evaluated according to heavy metal contents of soils such as Pb, Cu, Zn, Cd and Fe. These elements have more affinity to establish metallic bond with ferrous material leading to enhancement of soil magnetic susceptibility. The objective of this study was to undertake joint magnetic and geochemical investigations of road-side urban soil materials to address the environmental pollution of Beni Mellal city that has been subjected to environmental stress, due to population overpressure and related urbanization. Twenty three soils magnetic susceptibility profiles were made along 5 km peripheral national road (N8) in Beni Mellal. The magnetic survey reported here for the first time on this City’s topsoils tries to establish the link between magnetic properties and the content of heavy metals. High magnetic susceptibility values and high contents of heavy metals were found near the paved edge of the road and within the place reserved as large engine park. Magnetic extracts of highly polluted areas and unpolluted soil (olive plantation) were analyzed by SEM coupled with RDX in order to discriminate anthropogenic magnetic spherules and pedo-lithogenic magnetite-like minerals. Magnetic mineralogy determined by Mössbauer spectroscopy suggests the presence of hematite, magnetite and goethite in highly polluted areas. The iron oxides and especially goethite are efficient in incorporating and/or adsorbing foreign ions.  相似文献   

4.
This study presents a combined geochemical and mineralogical survey of urban surface soils. Many studies on urban soils are restricted to purely chemical surveys in order to investigate soil pollution caused by anthropogenic activities such as traffic, heating, industrial processing, waste disposal and many more. In environmental studies, chemical elements are often distinguished as lithogenic and anthropogenic elements. As a novel contribution to those studies, the authors combined the analysis of a broad set of chemical elements with the analysis of the main mineralogical phases. The semi-quantification of mineralogical phases supported the assignment of groups of chemical elements to lithogenic or anthropogenic origin. Minerals are important sinks for toxic elements. Thus, knowledge about their distribution in soils is crucial for the assessment of the environmental hazards due to pollution of urban soils. In Pforzheim, surface soils (0–5 cm depth) from various land use types (forest, agriculture, urban green space, settlement areas of various site densities) overlying different geological units (clastic and chemical sediments) were investigated. Urban surface soils of Pforzheim reflect to a considerable degree the mineral and chemical composition of parent rocks. Irrespective of the parent rocks, elevated concentrations of heavy metals (Zn, Cu, Pb, Sn, Ag) were found in soils throughout the whole inner urban settlement area of Pforzheim indicating pollution. These pollutants will tend to accumulate in inner urban surface soils according to the available adsorption capacity, which is normally higher in soils overlying limestone than in soils overlying sandstone. However, inner urban surface soils overlying sandstone show elevated concentrations of carbonates, phyllo-silicates and Fe and elevated pH values compared with forest soils overlying sandstone. Thus, in comparison to forest soils overlying sandstones, inner urban soils overlying sandstone affected by pollution concurrently possess elevated concentrations of mineral phases typically providing relatively high adsorption capacities for heavy metals.  相似文献   

5.
Chemical methods are generally chosen to monitor soil pollution but magnetic measurements proved to yield additional information at low cost and less time consumption. In this investigation, the novel use of rapid and non-destructive magnetic measurements to characterize Br levels in Xuzhou (China) urban roadside soils was reported. X-ray fluorescence spectrometry (XRF) was used to quantify Br in the soil samples. Data from 21 roadside soil samples confirm Br contamination, with a mean level of 4.36 mg kg−1 and a range of 2.4–8.7 mg kg−1. These values are higher than that of unpolluted soils in Xuzhou that averages 1.1 mg kg−1. Hierarchical clustering analysis shows Br in Xuzhou roadside soils is mainly from road traffic. Clear correlations between Br levels and simple magnetic parameters [mass specific susceptibility (χ LF), susceptibility of anhysteretic remanent magnetization (χ ARM), saturation isothermal remanence (SIRM)] are observed. The present study shows that these three magnetic parameters can be used as a proxy for Br levels in Xuzhou urban roadside soils.  相似文献   

6.
Two types of soil (fluvisols and anthrosols) were collected from different environmental settings (suburb and industrial area) in Wuhan, central China, aiming to examine the applicability of magnetic mapping for heavy metal pollution of urban soil in a large region. Magnetic measurements and chemical analysis indicated elevated magnetization and heavy metal concentrations of topsoils in the industrial area. Magnetic susceptibility (χ), anhysteretic remanent magnetization (ARM) and saturation isothermal remanent magnetization (SIRM) of fluvisols are much higher than those of anthrosols, but contrary for frequency-dependent susceptibility, indicating that soil magnetism strongly depends on the soil type/condition. Predominant magnetic carrier in topsoils in industrial area is pseudo-single-domain/multi-domain magnetite. Environmental scanning electron microscope/energy dispersive X-ray examination of the magnetic extracts from these topsoils revealed abundant spherical particles with diameters of 10–50 μm that are rich in iron-oxides, and could be attributed to the nearby industrial activities (e.g., steel work and power generation). Significant correlations were observed between magnetic concentration-related parameters (e.g., χ, ARM and SIRM) and concentrations of Cu, Pb, Zn, Hg and Tomlinson pollution load index. These results proposed that magnetic proxy mapping of soil pollution is an effective, fast and inexpensive tool for delineation of heavy metal pollution. However, interpretation of magnetic properties for such a purpose must be done on a site-specific basis, taking into account the possibilities of pedogenic enhancement/depletion under the specific soil conditions.  相似文献   

7.
Anthropogenic influence, mainly due to urban and industrial activities and traffic exhaust, may affect urban topsoil via atmospheric contamination and solid waste. Magnetic susceptibility measurements were conducted on 21 urban topsoil samples from the city of Xuzhou, China. High intensities of magnetic susceptibility were detected in the majority of the samples. SEM analysis shows that magnetic minerals are in the form of spherules and mainly due to anthropogenic inputs. The heavy metals Pb, Cu, Zn, Se, Sc, Mo, Fe, and Bi show strong correlations with magnetic susceptibility, and Ag, Ba, Cd, Ni, Cr, Sb, and Sn, on the other hand, show a weak correlation with magnetic susceptibility. Whereas, of these metals studied, only Hg has no significant correlation with the susceptibility. The Tomlinson pollution load index (PLI) also shows significant correlation with the susceptibility (χ). The present study shows that magnetic susceptibility is a fast, inexpensive, and non-destructive method for the detection and mapping of contaminated soils.  相似文献   

8.
城市土壤环境地球化学研究--以苏州市为例   总被引：4，自引：0，他引：4  
李家熙  葛晓立 《地质通报》2005,24(8):710-714
通过苏州城市环境地球化学调查工作的实施，对城市土壤环境地球化学研究的工作方法进行了初步研究。结果显示。苏州城市土壤的主要污染区域分布于东南居民生活区、西部工业区、东部木材加工厂集中区及公路干线一带；主要污染物为重金属、有机污染物多环芳烃、有机氯农药等。根据城市自然地理环境、功能分区特点和分布面积大小，确定土壤环境地球化学采样密度和测试项目是城市土壤环境地球化学研究的关键技术。  相似文献   

9.
Geophysical methods are widely applied to soils for resolving different tasks in precision agriculture, pollution evaluation, erosion estimation, etc. Environmental magnetic methods were applied in our study on a collection of soil samples from area near Rosslau (Germany), which was gathered on the basis of a field electromagnetic induction study. Magnetic laboratory analyses include magnetic susceptibility, isothermal remanent magnetization (IRM), anhysteretic remanent magnetization (ARM), thermomagnetic analyses for determination of the kind of magnetic minerals present in soils. The results reveal the presence of statistically significant inverse correlations between magnetic susceptibility, as well as remanent magnetizations ARM and IRM, and conductivity values. This maybe ascribed to influence of topography and water regime on the iron oxide forms in soil and the influence of soil moisture on soil conductivity. Magnetic measurements on soil cores showed close correspondence between soil horizons outlined in 1 m-long cores, and depth changes in mass-specific magnetic susceptibility. Existing relationships between magnetic characteristics, soil reaction pH, and nutrients’ content (total nitrogen, carbon and sulphur) have been explored by cluster analysis and general regression model statistics. The results reveal the presence of significant correlations between nutrients’ content, magnetic susceptibility and the grain size sensitive ratio ARM/χ. These are expressed by numerical equations, representing pedotransfer functions, which predict the content of Nitrogen, Carbon and Sulphur through combination of magnetic parameters and soil pH. The obtained pedotransfer functions for the particular case of Gley soils and Fluvisols studied could be used for application of magnetic methods in agricultural practice as a fast and inexpensive proxy evaluation of the content of these nutrition elements.  相似文献   

10.
The main purpose of the present study is to investigate the suitability of magnetic properties in correlation to geochemical measurements as a pollution-monitoring tool and study the metal transmission factors in an area around a major local source, namely a lignite-burning power plant. Surface soil samples were collected in the wide area of the power plant of Megalopolis (Peloponnesos, Greece). The magnetic susceptibility and other magnetic properties of the surface soils were originally measured and mapped. Loci of high values of magnetic susceptibility within the study area gave rise to further analyze the soil samples for metal concentrations. GIS techniques were used for mapping all the chemical constituent concentrations and the magnetic measurements on the various topographic and geological features of the area. Maps were created through interpolation algorithms indicating the spatial distribution of the above measurements. Spatial tools and statistical analysis through the calculation of Pearson’s coefficients proved the correlation between magnetic properties, metal concentrations and the terrain attributes (especially the geological structure and the wind currents) of the region.  相似文献   

11.
A total of 115 urban soil samples collected on grid bases from Al-Karak, South Jordan, were investigated for their field and dual-frequency magnetic susceptibility (χ field, χ d) and heavy metal content using Bartington susceptibility meters and ICP-MS. The upper soils have higher magnetic susceptibility values than lower soils, and large particles contain more heavy metals and higher magnetic susceptibility than smaller particles. This might be attributed to the lack of pedogenesis due to arid climate influence. Within the upper soil all heavy metal showed positive significant correlation with upper soil low-frequency χ dlf. This was evident from the distribution maps produced by Surfer 9.0 for χ dlf and heavy metals. The results showed that higher χ dlf is associated with traffic-dominated sites more than other areas. The frequency-dependent susceptibility (χfd %) falls between 2 and 10 %, which indicate the presence of admixture of fine supermagnetic particles. Mildly correlation exists between χfd % and χ dlf, which implies that soils contain anthropogenic multi-domain grains. Selected samples have been analyzed for their mineral constituents; the results indicate the presence of magnetite as the main magnetic mineral. This confirms the anthropogenic source of pollution mainly from the vehicle-related materials. The results indicate the applicability of magnetic susceptibility for pollution detection.  相似文献   

12.
Anthropogenic influence, mainly due to urban and industrial activities, may affect fluvial environments and soils, via atmospheric contamination and liquid and solid waste.Continuing previous works on stream sediments and soils, the Gran La Plata area was chosen. In this area, located in the Northeast of Buenos Aires Province (Argentina), several streams and soils were sampled. The streams have similar characteristics, although some of them have a higher input of pollutants (fluvial effluents, fly ashes, solid wastes, etc.). The studied soils have different pedological development.Magnetic and chemical studies were carried out in the laboratory. Analyses of the results indicated that the behavior of magnetic parameters can be related to the variations of heavy metal contents in stream sediments but there is not a good correlation in soils. The comparison between both environments (stream-sediment and soils) reveals a different impact of pollutants. Magnetite, especially PSD grains, seems to be the main carrier for both environments.  相似文献   

13.
We present a methodological approach to detect heated soil on ancient sites, using magnetic measurements. The method is based on changes in magnetic signals of soil by heating. The following three types of soil were used for testing the method: silty soil (SS), weathered volcanic ash (WVA, = loam) and fairly fresh volcanic ash (VA) called Odori tephra. On heating above 250–600°C, the magnetic susceptibility and remanent magnetization intensity increased for the SS and WVA samples, reflecting chemical alteration of magnetic minerals (from goethites to magnetites through hematites). The VA sample showed no susceptibility change suggesting the absence of goethites within it. On heating below 250°C, only the intensities of all the samples increased. This is possibly due to acquisition of thermal remanent magnetization. The largest change of the magnetic signals was identified for the SS sample and the smallest one was seen for the VA sample. Therefore, the in situ susceptibility measurement, which is the nondestructive and indirect method, seems to be effective to detect heated soil for sites of aqueous deposits as the SS. On the other hand, for sites of aeolian deposits as the WVA (loam) and VA, the intensity measurement of collected soils seems to be the most reliable method to detect evidence of heating. The degree of the magnetic stability (coercivity) against progressive alternating-field demagnetization was also an important parameter, indicating whether the investigated soils were heated or unheated. © 1999 John Wiley & Sons, Inc.  相似文献   

14.
济南市土壤元素地球化学特征及环境质量   总被引：3，自引：3，他引：0       下载免费PDF全文
以济南市土壤为研究对象,采用R-2.6.1程序、半方差函数模型和因子分析法对区内土壤元素含量统计特征、结构特征和分布特征进行了分析研究,并对土壤环境质量进行评价。结果表明:研究区土壤中多数元素含量总体受自然空间格局控制,但人类活动对市区土壤Cd、Hg、Pb、Se、As、p H值等元素(指标)含量有明显影响,表层土壤p H值呈现从外围向市区中心增加的碱化趋势;盛行风向对表层土壤重金属的分布叠加也产生影响,沿顺风向产生漂移。受人类活动(主要为工业污染)历史长短及强度的不同,济南市区、历城区和章丘市总体为轻度污染,局部存在Hg、Cu、Cr、Cd等中度或重度污染,污染区分布与各类工业空间布局相吻合,而长清、济阳土壤环境质量较好,总体属警戒限级。按土壤综合污染指数排序,土壤综合环境质量从优到劣为济阳长清章丘历城市区。  相似文献   

15.
Urban soil research has invoked great interest in recent years.Previous studies were mainly focused on urban soil physics and chemistry,and soil geography to constrain the source,distribution,transport and deposition of pollutants such as heavy metals and health-hazardous organic matter,bu t litte has been done on soil microbiology.In this paper,the authors reported the variation of microbial features in urban soils compared with those from adjacent rual areas.The results show great changes in basal respiration rates microbial biomass and ecophysiological parameters have taken place in urban environment because of the anthropogenic stress, thus activating the microorganisms.As a result,much more energy,carbon is consumed at a low utilization efficiency.So microbial biosensors can be used to indicate urban environmental pollution effectively.  相似文献   

16.
Mumbai metropolitan region (MMR) in India represents one of the most industrialized and thickly populated areas of the monsoon dominated Asian region. We present here pre- and post-monsoon magnetic susceptibility variations in the top-soils representing sampling domains of industrial, heavy traffic and forested areas within MMR. The rock magnetic studies (including isothermal and anhysteric remanent magnetization and hysteresis loop analysis) infer predominant pseudo single domain to multi domain grains in an overall ferrimagnetic dominant mineralogy of the soils. The susceptibility-temperature variations (from ?190 to 700°C) infer maghemite (??-Fe2O3) as the chief mineral component of pedogenic origin, and the pure magnetite (Fe3O4) is of anthropogenic nature. Spatial distribution of ferrimagnetic concentration is in agreement with polluting sources. The post-monsoon redistribution pattern is greatly controlled by the surface runoff and topographic conditions. The study demonstrates that in a ferrimagnetically reach substrate like MMR, the spatial distribution patterns derived from routine concentration- and grain-size-dependent rock magnetic parameters integrated with topographic and seasonal attributes yield significant information on the style and surface re-distribution of anthropogenically loaded soils and sediments to identify its seasonal dumping. Alternatively, knowing the source of signal, the magnetic susceptibility can be further used as a robust parameter to produce detailed maps to monitor the pollutions in urban areas.  相似文献   

17.
To characterize a runoff pattern of non-point pollutants in relation with different land uses in a watershed, a monitoring activity and field measurements were carried out and data points were recorded during the rainfall events for 2 years. The study area includes industrial, urban, and rural sectors, which can represent a model case for the runoff study. Each sector was monitored with methodology and parameters including partial event mean concentration, first flush effect, mass first flush ratios, and correlation analysis. The Banwol Industrial Outfall No. 4 (4TG), an industrial area, showed a strong first flush effect, indicating that pollutants such as suspended solids, chemical oxygen demand, total nitrogen, and total phosphorus, were discharged at the early stage of a storm. An MFF30 analysis of the runoff revealed a mean pollutant load was over 50 %. In the Ansan Stream, an urban area, a strong first flush effect did not appear; however, the concentrations of pollutants reached a peak some time later during a storm event. Then, the concentrations of pollutants quickly reduced. On the other hand, Jangjunbo and Munsan Stream, rural areas, did not exhibit the first flush effects, and when considering the value of MFF30, 30 % or fewer pollutants on average were discharged at the initial stage of a storm. This means most of pollutants were streamed out at the later time of a storm event. The monitoring results found that the runoff characteristics of non-point pollutants in industrial, urban, and rural areas were distinctly different and site-specific. Therefore, each watershed management plan should be prepared to meet its own characteristics. Also, this kind of data can be an important base in designing and sizing a regional wastewater treatment facility to treat pollutants from a contaminated watershed.  相似文献   

18.
三峡库区消落带土壤磁性变化规律及成因探讨   总被引：2，自引：0，他引：2  
为动态跟踪三峡库区消落带土壤物性在水位上涨后所受影响,选择重庆市忠县石宝寨镇长江左岸一带作为研究区,以消落带外同类型土壤作对照,从分析不同水位土壤的磁学性质入手,探究三峡库区蓄水前后土壤性质对环境变化的响应。库区蓄水后,不仅导致了消落带内土壤理化性质变化,还使土壤磁性空间分布在不同水位这一维度上发生显著改变。消落带监测断面数据显示,土壤磁性由蓄水前垂直方向上较稳定的分布,变为目前整体上随淹没水深增加而增高的特征;169~175 m高程附近,土壤磁性接近当地同类土壤背景值,而低于此高度尤其是低于157 m后,磁化率值迅速增高。磁性的变化是库区蓄水后土壤磁性矿物组成发生改变造成的,由热磁曲线可知,次生磁铁矿的加入是首要原因。扫描电镜下观测出的浑圆状磁铁矿的最可能来源是上游燃烧化石燃料排放的磁性外来污染物,其随江水输运至此并沉积吸附在土壤颗粒上。研究结果为间接监测污染物的迁移提供了依据。  相似文献   

19.
长江中下游第四纪沉积物发育土壤磁性增强的环境磁学机制   总被引：25，自引：2，他引：23  
对长江中下游第四纪沉积物 (Q3 黄土,Q2 红土和Q3 红土 )发育土壤的磁性增强现象及其物理机制进行了讨论。结果表明 :(1)铁磁性矿物是土壤磁性的主要载体,它们是成土过程中形成的稳定单畴 (SSD)和超顺磁性 (SP)态的次生磁性矿物,没有显示重要的反铁磁性矿物的贡献;(2 )土壤磁化率 (χ)的高低与成土过程产生的稳定单畴和超顺磁性颗粒呈极显著正相关,指示了风化成土作用的强度,磁化率可作为反映成土环境变化的代用指标;(3)频率磁化率 (χfd) 5 %可作为土壤中的超顺磁性颗粒存在与否的临界值,土壤 χfd值的高低同样反映了风化成土作用的强度,可用作研究第四纪环境变化的有用工具之一。  相似文献   

20.
Environmental degradations caused by erosion and landslide within an area in the South-eastern part of Nigeria were assessed, and also an attempt to characterize the underlying soils based on their degree of susceptibility to erosion and landslide. Factors affecting soil erodibility such as physical and chemical properties of soil, as well as vegetation density and slope gradient was determined in 20 different areas. Simple linear regression and principal component analysis were employed to relate the factors controlling erosion and landslide to the erosion and slide densities, and to determine the pattern that exists in the data and as well express the data in such a way as to highlight their similarities and differences. Four vertical horizons and two horizontal zones of soil were distinguished based on their degree of weathering as well as their chemical and mineralogical composition; hence the soils were classified into six different types based on their degree of susceptibility to erosion and landslide. Variations in their degree of susceptibility to erosion and landslide were majorly controlled by its chemical and mineralogical composition rather than its particle size distribution.  相似文献   

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