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1.
针对日益突出的环境问题,磁学方法依靠自身便捷、经济等一系列优势在环境污染研究方面得到了广泛的应用.文章总结了环境研究中磁性矿物的特征和鉴别方法及主要的环境磁学参数,回顾了磁学方法在地表沉积物污染、水环境污染和大气环境污染方面的应用进展.并指出增进对磁性物质与污染源关系、污染物磁性形成机理的理解,加强从单纯的磁化率测量到多磁性参数的综合运用以及与矿物学、地球化学等方法的结合来查明污染物质的多源性、记录环境信息在时空尺度上的不确定性和不同环境对污染物承载能力的差异性,是提高磁学方法在环境污染研究领域应用效果的关键,有利于使环境污染监测和评价由定性研究向定量化研究发展. 相似文献
2.
环境磁学理论、方法和研究进展 总被引：32，自引：1，他引：31
环境磁学是一门介于地球科学、环境科学和磁学之间的边缘科学。环境磁学可提供大量有关区域或全球环境变化及人类活动对环境影响等的重要信息,其研究范围迅速扩大,已成为当今地学前沿学科之一。本文在简述了环境磁学的理论和方法的基础上,介绍了环境磁学中几个主要研究领域如古气候与古环境变化、土壤学和环境污染研究等方面所取得的进展,指出了环境磁学研究中存在的不足之处,并提出了近年来环境磁学的一些新的发展趋势：①加强磁信息与地质记录之间的定量研究;②利用磁信息加强应用研究;③环境磁学与地球化学方法密切相结合;④建立全球磁数据 相似文献
3.
对北京首都机场高速公路旁采集的土壤柱状T01剖面的磁学参数和金属元素分析,探讨了研究区内现代交通导致的土壤磁学性质的变化及其对环境污染的响应.结果表明,磁参数(χ,ARM和SIRM)与重金属含量呈同步垂向变化趋势.来源于交通运输排放的污染物是土壤剖面上部(0～8 cm)磁性和金属含量增强的主要原因,8cm以下,土壤基本未受到污染,磁性矿物和重金属含量较低,磁性颗粒变化稳定,基本代表了该地区土壤的自然背景.尽管土壤岩石磁学分析表明剖面上下部受污染和未受污染样品的磁载体均是粒度较粗的多畴磁铁矿,但是结合磁参数比值曲线,说明底部样品的磁颗粒的粒度较顶部偏细.磁性矿物的含量变化没有影响磁颗粒的粒度特征.指标聚类等相关分析表明,土壤磁参数(χ,ARM和SIRM)与重金属元素(Pb,Zn和Cu)含量显著相关;结合模糊聚类分析,磁参数可用于追踪、识别交通污染物质在土壤剖面中的富集、迁移状态,揭示不同深度土壤的污染程度. 相似文献
4.
趋磁细菌是一类特殊的微生物,它们在体内合成有生物膜包裹、粒度均一(35 ～ 120 nm)、结晶程度高、晶形特殊、呈链状排列的磁小体,其化学成分主要是磁铁矿( Fe3O4)或胶黄铁矿(Fe3S4),因此,它们能沿地磁场磁力线定向游弋.研究表明,趋磁细菌广泛分布在淡水和海洋环境中,细胞数量可达105～ 107个/ml,其多样性和地理分布与环境有密切关系.磁小体在趋磁细菌死后可以保存在沉积物中,化石磁小体对沉积物磁学性质有重要贡献,而且趋磁细菌活动在全球铁元素循环和维持生态系统功能等方面发挥重要作用.本文综述了近年来趋磁细菌多样性、地理分布格局、环境磁学以及古环境重建等方面的研究进展.值得指出的是,化石磁小体可作为重构古环境的生物标志物,应予以重视. 相似文献
5.
中国黄土-古土壤系列的磁学性质,如磁化率等被广泛用于古气候和古环境研究,这必须建立在对黄土-古土壤的剩磁的性质和获得剩磁的机制以及古土壤磁性增强的原因有深入了解的基础之上。作者通过对洛川和吉县剖面马兰黄土和离石黄土的磁学性质的深入研究,对黄土与古土壤磁学性质差异的各种表现,对它们剩磁的性质,对古土壤磁性增强的原因以及磁性变化对古气候、古环境研究的意义进行了讨论,并对利用某些磁学性质建立的黄土-古土壤形成的时间模式提出了质疑。 相似文献
6.
地磁学、古地磁学和环境磁学的研究新进展——第32届国际地质大会学科总结和评述 总被引：6，自引：3，他引：3
第32届国际地质大会接受关于地磁学、古地磁学、环境磁学方面的摘要120余篇,主要内容涉及：（1）古地磁学在古大陆再造中的应用;（2）地磁场倒转和长期变的理论、观测和应用以及磁性地层学;（3）磁化率测量在地层划分和对比中的应用;（4）气候变化的环境磁学证据;（5）环境污染监测的环境磁学方法等研究领域。此外,磁法勘探也有很好的成果展出。基于物质磁学和地磁学的方法技术在日益广阔的地学研究领域中有很好的应用前景。 相似文献
7.
近年来,环境磁学方法被广泛应用到古环境和现代环境问题的研究中[1～4].不同种类的磁性矿物具有不同的磁性强度以及磁畴范围[1],磁性矿物种类的确定是研究需要解决的首要问题.目前磁性矿物种类主要运用环境磁学比值参数,以及热磁曲线、磁滞回线等传统的磁学方法鉴别[5～8],然而这些方法对弱磁性矿物(如反铁磁性矿物)不敏感,信号常被亚铁磁性矿物掩盖.近年来,XRD矿物衍射[9,10]、漫反射光谱[11]等技术被引入到磁性矿物鉴别中,但矿物衍射的方法对于研究对象中磁性矿物的含量有一定要求,对于磁性矿物含量比较低的天然样品,如被有机质以及其他矿物稀释的湖泊沉积物,难以满足实验要求. 相似文献
8.
为了研究树叶的磁学性质对大气环境污染的指示作用,对安徽省凤阳县城、水泥厂和石英砂厂生长的杨树叶及在凤阳县城生长的银杏树、梧桐树等树叶的磁学参数进行测量。结果显示树叶样品中主要磁性矿物都是磁铁矿,粒径较大;但不同环境生长的杨树叶中磁性矿物含量存在差异,由高到低依次排列为水泥厂、凤阳县城、石英砂厂,指示水泥厂大气环境污染较凤阳县城和石英砂厂严重。进一步分析还发现在凤阳县城采集的杨树、银杏树、梧桐树等树叶样品中磁性矿物含量各不相同,其中银杏树叶中磁性矿物含量高于杨树和梧桐树树叶。利用树叶磁学参数能监测大气环境污染,但不同树种树叶的磁学参数对大气环境污染的指示作用存在差异。 相似文献
9.
山西太原盆地土壤磁化率与元素Cd、Pb相关性分析研究 总被引：1，自引：0，他引：1
磁化率是环境磁学研究中的一个重要磁参数[1],受污染的土壤随着磁化率的增加往往伴随着许多有害的重金属出现,因而磁化率与地球化学元素相关性研究,成为近些年环境磁学研究新的发展趋势之一[2]. 相似文献
10.
11.
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
12.
利用直流电测深、环境磁学以及矿物学方法,开展对一钢铁厂周边土壤的污染评价研究,获得了土壤垂向电阻率与磁化率分布特征。研究表明,随着污染土剖面的深度由底部至地表,土壤电阻率逐渐减小,磁化率和重金属含量反而增高;该变化特征反映了土壤受污染的程度与钢铁公司历年粗钢产量及武汉市历年汽车保有量的变化程度相对应。通过对污染样品的磁滞回线、热磁曲线和SEM/EDX等矿物学分析,污染样品的矿物成分以磁铁矿和赤铁矿为主,以准单畴(PSD)颗粒存在,形貌特征和物质成分与成土过程中形成的磁性颗粒明显不同。由于土壤的电性与磁性都具有良好的污染程度指示作用,所以土壤的电性与磁性研究可以应用于土壤污染程度的评价,两者联合运用可大大提高土壤污染程度评价的分辨率。 相似文献
13.
R VENKATACHALAPATHY S VEERASINGAM N BASAVAIAH T RAMKUMAR K DEENADAYALAN 《Journal of Earth System Science》2011,120(5):885-895
In this study, environmental magnetic, heavy metal and statistical analyses were conducted on 21 surface sediments collected
from Chennai coast, India, to examine the feasibility of heavy metal pollution using magnetic susceptibility. The Chennai
coastal sediment samples are dominated by ferrimagnetic minerals corresponding to magnetite-like minerals. The percentage
of frequency dependent magnetic susceptibility reflects the presence of super-paramagnetic/single domain magnetic minerals
in Chennai harbour, Cooum and Adayar rivers sediments. High pollution load index in sample E1, E2, CH7, C11, C12 and A16 is
mainly due to anthropogenic activities such as, harbour activities, Cooum and Adayar rivers input and industrial effluent.
Factor analysis shows that the magnetic concentration dependent parameters (χ, χ
ARM and SIRM) covary with the heavy metal concentrations, suggesting that the input of magnetic minerals and heavy metals in
Chennai coastal sediments are derived from the same anthropogenic sources. Strong correlation obtained between pollution load
index (PLI) and concentration dependent parameters (χ, χ
ARM and SIRM) for the polluted samples with magnetic susceptibility excess of 50×10 − 8 m3kg − 1. Significant correlations between heavy metals and magnetic susceptibility point out the potential of magnetic screening/monitoring
for simple and rapid proxy indicator of heavy metal pollution in marine sediments. 相似文献
14.
Marcos A. E. Chaparro Ana M. Sinito V. Ramasamy Claudia Marinelli Mauro A. E. Chaparro S. Mullainathan S. Murugesan 《Environmental Geology》2008,56(2):425-437
Rock-magnetic techniques have become a useful tool in environmental issues; in particular, magnetic studies constitute an
alternative way to study pollution in different media. The present contribution focuses on magnetic parameters as pollution
indicators, especially from their relationship with contents of heavy metals. The work was carried out in two Indian rivers
located in Tamil Nadu, southern India. Several sediment samples were collected and studied in the laboratory using magnetic
techniques, magnetic susceptibility, anhysteric remanent magnetization, isothermal remanent magnetization, and chemical techniques
to determine contents of heavy metals. Magnetic mineralogy indicates the predominance of ferrimagnetic minerals; although
magnetite-like minerals are the main magnetic carriers, antiferromagnetic minerals can be present as subordinate carriers.
Concentration-dependent magnetic parameters revealed noticeable differences between both rivers, e.g. magnetic susceptibility
is four times higher in Cauvery than in Palaru River. Moreover, such increase can be interpreted as “magnetic enhancement”
and therefore related to the pollution status. This magnetic enhancement indicated a different pollutant contribution in both
rivers, and also, a different spatial distribution along these rivers, where critical (or more polluted) sites were identified.
On the other hand, univariate and multivariate statistical analyses—e.g. PCoordA, Multifactorial Analysis of distance, PCA
and RDA—were examined, revealing a link between magnetic and chemical variables. Among magnetic parameters, the concentration-dependent
magnetic parameters (e.g. magnetic susceptibility) seem to be the most relevant for this study. 相似文献
15.
Magnetic properties of urban topsoils and correlation with heavy metals: a case study from the city of Xuzhou, China 总被引：1，自引：0，他引：1
Heavy metals in urban topsoils have been shown to be very useful tracers of environmental pollution. Thus, their detailed
studies are of great importance. Apart from expensive and time-consuming chemical methods, several simple, rapid and cheap
proxy methods have been developed recently, one of them being based on rock-magnetic parameters. This examines the use of
rock-magnetic methods designed to assess the degree of heavy-metal pollution of urban topsoils from the city of Xuzhou (China).
The aim was to identify the magnetic properties and to link the “magnetic pollution” to the concentrations of the heavy metals.
Since a strong correlation has been found between saturation isothermal remanent magnetization (SIRM) and the heavy metals,
namely, Fe, Se, Ti, Sc, Ba, Bi, Pb, Cu, Zn, Cr and Mo, an anthropogenic contamination origin is thought to be the cause. The
present study shows that SIRM is a fast, inexpensive and non-destructive method for the detection and mapping of heavy-metal-contaminated
urban topsoils. 相似文献
16.
Tayel El-Hasan 《Environmental Geology》2008,54(1):23-29
This work is a complementary investigation to the earlier urban soil survey for a rapidly growing city of relatively high
traffic density. Therefore, it aims to apply the environmental magnetism approach to assess the roadside pollution at a known
polluted site. The used magnetic proxies are the initial magnetic susceptibility and saturation magnetization. The results
prove the applicability of this method in detecting roadside pollution. The shape and magnitude of the magnetic signals was
affected by the topography and prevailing wind direction that caused the magnetic peaks to be shifted accordingly. Particle
size was found to affect the magnetic material content, where sand size (63–150 μm) bears the highest magnetic signals relative
to smaller silt size (<63 μm). The magnetic anomalies coincided positively with heavy metal pollution in the studied site,
which might indicate that the magnetic materials serve as an effective proxy for the metallic pollution (i.e., Fe, Ni, Pb,
Cu, and Zn) originated mainly from vehicular sources. 相似文献
17.
Heavy metal pollution and soil magnetic susceptibility in urban soil of Beni Mellal City (Morocco) 总被引：3，自引：2，他引：1
Mohamed El Baghdadi Ahmed Barakat Mohamed Sajieddine Samir Nadem 《Environmental Earth Sciences》2012,66(1):141-155
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
18.
以24 186个表层土壤(0～20 cm)和6 127个深层土壤(150～200 cm)样品之Cd、Hg、Pb、As等含量数据为基础,研究了江苏全省土壤环境的重金属分布与主要污染特征.结果表明.全省自然土壤环境与人为活动土壤环境的重金属元素分布都不均匀,但人为活动土壤环境中的不均衡程度远高于自然土壤环境:全省农田中有1.02%的土壤受到Cd、Hg、Pb等8种重金属的严重污染,苏州市、无锡市土壤环境被重金属污染的程度相对严重;工业化、城市化进程中的人为活动及自然地质作用都是引起江苏局部土壤重金属污染的重要原因,自然成因的重金属污染土壤多呈面状、多元素、低强度、双层污染等特点,从而与人为成因的重金属污染土壤有所区别. 相似文献
19.
Mapping of heavy metal loadings in soils by means of magnetic susceptibility measurements 总被引：13，自引：0，他引：13
Contamination of soils with heavy metals is an issue all industrial and urban regions have to deal with. Generally, chemical methods are chosen to monitor soil pollution but measurements of magnetic susceptibility proved to yield additional information at low cost and consuming less time. We measured the magnetic susceptibility of soils which had been analysed chemically during the soil surveys of three Austrian provinces. Each anomaly of susceptibility either coincided with geogenic anomalies or indicated anthropogenic input of pollutants. Regional comparisons of susceptibility with chemical analyses revealed that susceptibility can be used as an indicator for the contents of individual pollutants in soils. This calibration of susceptibility has been successfully applied to an industrial region as well as to an urban environment. Two powerful applications of susceptibility measurements of soils are shown: the identification of polluted areas, and the detailed mapping of these areas to reveal the extent of pollution. 相似文献