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1.
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
2.
A statistical approach for determining the environment impact of surface sediments from the Dongting Lake area,central China 总被引：1，自引：1，他引：0
YAO Zhigang BAO Zhengyu ZHOU Lifa GAO Pu Key Laboratory of Continental Dynamics Ministry of Education/Department of Geology Northwest University Xi’an China School of Petroleum Resources Xi''an Shiyou University Xi''an China State Key Laboratory of Geological Processes Mineral Resources China University of Geosciences Wuhan China 《中国地球化学学报》2009,28(1):97-104
The Dongting Lake, the second biggest freshwater lake in China, consists of three wetlands of national importance, namely the East Dongting Lake, the South Dongting Lake, and the West Dongting Lake. Surface sedi-ments were sampled from 57 locations across the lake. Nutrient concentrations [total organic carbon (TOC), total N (TN) and total P (TP)] and 16 element concentrations (Al, As, B, Ca, Cd, Cr, Cu, K, Fe, Hg, Mn, Ni, Pb, Si, Ti and Zn) in the sediments were measured to investigate the impact of industrialization along the lake's coastline and sev-eral tributaries on the profiles of nutrients and heavy metals in the lake's surface sediments. R-mode cluster analysis (CA) was used to integrate geochemical data. The result showed that euthophication of the Dongting Lake resulted mainly from TN and TOC. The main polluting trace metals are Hg, As, Cd, Zn, Pb and Mn, which are largely ad-sorbed on clay minerals or Fe/Mn oxides, or deposited as carbonates. Principal component analysis (PCA) revealed the source of micropollutants. The worst affected district by heavy metals is the East Dongting Lake, the pollution sources may originate mainly from the Xiangjiang drainage area. The results demonstrated that multivariate methods are the potentially great tools for the interpretation of the environmental data on lake sediments. 相似文献
3.
Concentrations of heavy metals and polycyclic aromatic hydrocarbons in river sediments: geochemical background,man's influence and environmental impact 总被引：11，自引：0，他引：11
Sediment analysis is used for detecting pollution sources; in addition, sediments are increasingly investigated as a pollution
proper and as a carrier and possible source of contaminants in aquatic systems.
Amongst the various groups of pollutants which possess a strong affinity to sedimentary materials, heavy metals and polycyclic
aromatic hydrocarbons present the greatest environmental hazard.
A review is given of pre-civilisational concentrations (“background” values) of both heavy metals and polycyclic aromatic
hydrocarbons in fluviatile sediments, and their development during the past 100 years. The impact of sediment associated heavy
metal pollution on both biota and water is discussed. 相似文献
4.
Dissolved trace elements and heavy metals from the shallow lakes in the middle and lower reaches of the Yangtze River region,China 总被引：2，自引：1，他引：1
Dissolved trace elements and heavy metals of waters and sediments in the ten shallow lakes in the middle and lower reaches
of the Yangtze River region were determined to identify their composition and spatial distribution, and to assess the extent
of their environmentally detrimental effects by comparison with water and sediment quality guidelines. Results indicated that
As and Pb were the main pollutants in lake waters and Mn and Hg the potential ones, while As, Cu and Pb were the main pollutants
in lake sediments. Their spatial distribution indicated that Daye Lake was seriously polluted by metals, which was corroborated
by cluster analysis. Higher concentrations of trace elements have been found in lakes downstream of the Yangtze River delta,
and higher concentrations of metals have been recorded in sediments of upstream lakes, suggesting that metals in water were
more sensitive to anthropogenic activities and that metals in sediment were mainly controlled by minerals. Correlation analyses
demonstrated that there were stronger associations among metals in lake sediments than those in lake waters, and their good
relationships suggested the common sources. Further research on the subject will help develop water quality management with
the aim of restoring shallow lakes in the Yangtze River. 相似文献
5.
Magnetic susceptibility measurements were conducted on 24 vibrocores obtained from an area located off the northeastern coast
of Lantau Island in Hong Kong. High intensities of magnetic susceptibility were detected in the uppermost sections of the
majority of the cores. Several magnetic parameters measured for one of the cores suggest that the variations in the magnetic
characteristics over depth are mainly due to varying concentrations of the magnetic minerals. Since a strong correlation has
been found between magnetic susceptibility and the heavy metals Pb, Cu, Zn and Cr, an anthropogenic contamination origin is
thought to be the cause. The present study shows that magnetic susceptibility is a fast, inexpensive and non-destructive method
for the detection and mapping of contaminated sediments.
Received: 12 August 1997 · Accepted: 18 November 1997 相似文献
6.
A. Parizanganeh B.Sc. M.Sc. Ph.D. V. C. Lakhan Ph.D. F.R.G.S. C.E.I. C.E.S. H. Jalalian Ph.D. 《International Journal of Environmental Science and Technology》2007,4(3):351-358
The nearshore marine environment of the Caspian sea is a major repository for toxic metals originating from various sources. Since the persistent toxic metals pose serious health risks this research concentrated on investigating the concentrations and spatial distribution of metals in the nearshore sediments along the Iranian coast of the Caspian sea. Fourteen sampling sites were selected along the coast and approximately 400 g of surficial sediments were obtained. Samples were sieved and three grain size fractions from each sample plus fourteen bulk samples were selected for the analysis of metals. Laboratory analysis of the samples utilized the Cold Acetic protocol, followed by Inductively coupled plasma optical emission spectroscopy. The statistical techniques were used to analyze all obtained data. Linear regression analysis demonstrated that grain size of the sediments was not a major factor controlling the concentrations and spatial distributions of heavy metals. Box and Whisker plots emphasized that metal concentrations were not homogeneously distributed. Discriminant analysis was also proved to be useful in identifying geographic areas where heavy metal concentrations occur along the coast. 相似文献
7.
沉积物微量金属元素在重建水体环境变化中的意义 总被引：7，自引：0，他引：7
沉积物所记录的微量金属含量与形态的变化是指示人类活动影响下水体环境变化的有效指标,主要用于指示沉积物重金属污染、水体初级生产力变化和氧化还原条件等方面的水体环境状况。总体而言,沉积物中微量金属含量在近一个世纪以来显著上升,反映了采矿、冶金、污水排放、化肥使用、煤炭和石油燃烧等各种人类活动造成水体和沉积物重金属污染的记录作为浮游植物微量营养元素,Cu、Zn、Ni、Ba、Cd等在沉积物中的记录可以指示水体初级生产力水平。U、Mo、V、Cu、Cd、Mn等氧化还原敏感元素在沉积物中的富集或贫化,及其比值(如Re/Mo、Cd/U、Th/U和V/Sc)的变化,是指示水体和沉积物氧化还原环境的有效指标。但需要指出的是,在受人类活动影响的水体中,这些生产力和氧化还原指标很少能指示水体生产力或氧化还原状况,可能主要与人类活动同时造成这些金属元素大量污染输入而掩盖了其自生来源和内在变化的沉积记录有关。所以,对沉积物中微量金属元素来源的判别(陆源碎屑输入、人为输入和水体自生来源)是重建水体环境变化的重要前提。本文总结了多种化学和统计学方法(包括同位素示踪法、化学提取法、富集因子法和主成分分析法等)在沉积物金属来源判别中的应用另外,成岩作用等多种因素会干扰沉积物金属记录对环境变化的指示作用,所以构建多元素指标来综合判断沉积物记录所反映的环境信息是今后的研究所必须关注的 相似文献
8.
Kananathan Amalan Amila Sandaruwan Ratnayake Nalin Prasanna Ratnayake Shanaka Maduranga Weththasinghe Nimila Dushyantha Nalika Lakmali Ranjith Premasiri 《Environmental Earth Sciences》2018,77(21):737
Beach sediments in Sri Lanka contain industrial-grade heavy mineral occurrences. Samples of both offshore and onshore sediments were collected to examine the provenance, mineralogy and geochemical compositions of the heavy mineral occurrences. Coastal morphodynamic changes along the coastline of Sri Lanka were analyzed using the time-series satellite images. These coastal morphodynamic changes were used to identify the prominent directions of monsoon-influenced longshore currents, coastal sediment accretion and depositional trends and their relationships to the provenance of the heavy minerals. Results show the concentrations of detrital ilmenite, zircon, garnet, monazite, and rutile vary in the onshore and offshore sediments. The heavy mineral potential of the northeastern coast is high (average contents of about 45–50% in the Verugal deposit, 70–85% in the Pulmoddai deposit, and 3.5–5.0% in offshore samples stretching from Nilaveli to Kokkilai), compared to sediments in southwest (average content about 10% in onshore sediments and 2% in offshore sediments from the mouth of the Gin River). Therefore, no economic-grade heavy mineral placers were identified in the offshore environments. The high concentrations of heavy minerals in beach sediments and low concentrations in offshore sediments suggest operation of a panning system in the surf zone to form enriched placer deposits. Major and trace element compositions of beach sediments show marked enrichments of TiO2, Fe2O3, La, Ce, Zr, Cr, Nb, Th and V compared to average Upper Continental Crust (UCC) values. Analysis of prominent coastal longshore transport patterns identifies bidirectional sediment transport in the northeast coast of Sri Lanka. In the southwestern coast, two transport directions occur with anti-clockwise transport from Galle to Hambantota, and clockwise transport from Hikkaduwa to Wadduwa. The heavy minerals in the placers were mainly derived from Precambrian metamorphic rocks, and transported to the coast through the river systems of Sri Lanka. 相似文献
9.
本研究对湘江下游河床沉积物进行了元素地球化学分析,在认识沉积物元素地球化学特征、甄别人为源与自然源重金属的基础上,估算了沉积物的元素地球化学背景值。结果表明:SiO2、TiO2、Al2O3、Fe2O3、K2O等主量元素及V、Co、Cr、Ba、Sc、U、Sr、Ga、Ge、Rb、Nb、Y、REE等微量元素在沉积物中含量变化相对稳定(Cv<0.2),分布相对均匀,且富集不明显(EF<2.0,Sr明显亏损)。而MnO、MgO、CaO、Na2O、P2O5等主量元素,及Cd、Mn、Cu、Pb、Zn等重金属在沉积物中含量变化大(Cv>0.25),分布极不均匀,且沉积物中重金属明显富集(EF>2.0)。主成分及Pearson线性相关性分析显示,沉积物中不明显富集的微量元素主要赋存于难溶硅酸盐矿物相中,为自然源元素。而沉积物中显著富集的重金属主要赋存于铁—锰氧化物等矿物相中,为有人为源叠加的元素。故针对不同来源特征的元素用不同的方法进行了背景值计算,求得沉积物中47个元素的背景值。再利用元素比值等方法对所得背景值进行检验。结果表明,本文得到的湘江沉积物元素背景值合理,可用作流域沉积物重金属污染评价参考。 相似文献
10.
Adeline CharriauLudovic Lesven Yue GaoMartine Leermakers Willy BaeyensBaghdad Ouddane Gabriel Billon 《Applied Geochemistry》2011,26(1):80-90
Three sediment cores were collected in the Scheldt, Lys and Spiere canals, which drain a highly populated and industrialized area in Western Europe. The speciation and the distribution of trace metals in pore waters and sediment particles were assessed through a combination of computational and experimental techniques. The concentrations of dissolved major and trace elements (anions, cations, sulfides, dissolved organic C, Cd, Co, Fe, Mn, Ni, Pb and Zn) were used to calculate the thermodynamic equilibrium speciation in pore waters and to evaluate the saturation of minerals (Visual Minteq software). A sequential extraction procedure was applied on anoxic sediment particles in order to assess the main host phases of trace elements. Manganese was the most labile metal in pore waters and was mainly associated with carbonates in particles. In contrast, a weak affinity of Cd, Co, Ni, Pb and Zn with carbonates was established because: (1) a systematic under-saturation was noticed in pore waters and (2) less than 10% of these elements were extracted in the exchangeable and carbonate sedimentary fraction. In the studied anoxic sediments, the mobility and the lability of trace metals, apart from Mn, seemed to be controlled through the competition between sulfidic and organic ligands. In particular, the necessity of taking into account organic matter in the modelling of thermodynamic equilibrium was demonstrated for Cd, Ni, Zn and Pb, the latter element exhibiting the strongest affinity with humic substances. Consequently, dissolved organic matter could favour the stabilization of trace metals in the liquid phase. Conversely, sulfide minerals played a key role in the scavenging of trace metals in sediment particles. Finally, similar trace metal lability rankings were obtained for the liquid and solid phases. 相似文献
11.
《Applied Geochemistry》2003,18(3):409-421
This study provides a geochemical partitioning pattern of Fe, Mn and potentially toxic trace elements (As, Cd, Cr, Cu, Ni, Pb, Zn) in sediments historically contaminated with acid mine drainage, as determined by using a 4-step sequential extraction scheme. At the upperstream, the sediments occur as ochreous precipitates consisting of amorphous or poorly crystalline oxy-hydroxides of Fe, and locally jarosite, whereas the estuarine sediments are composed mainly of detrital quartz, illite, kaolinite, feldspars, carbonates and heavy minerals, with minor authigenic phases (gypsum, vivianite, halite, pyrite). The sediments are severely contaminated with As, Cd, Cu, Pb and Zn, especially in the vicinity of the mining pollution sources and some sites of the estuary, where the metal concentrations are several orders of magnitude above background levels. Although a significant proportion of Zn, Cd and Cu is present in a readily soluble form, the majority of heavy metals are bonded to reducible phases, suggesting that Fe oxy-hydroxides have a dominant role in the metal accumulation. In the estuary, the sediments are potentially less reactive than in the riverine environment, because relevant concentrations of heavy metals are immobilised in the crystalline structure of minerals. 相似文献
12.
《Applied Geochemistry》2003,18(6):781-794
This study presents the results on heavy metal (Mn, Fe, Cu, Zn) analyses of sediments taken from Euvoikos Gulf, Greece, which is a semi-enclosed system receiving pollution loads from several urban and industrial sources and is affected by a strong tidal current. A sequential extraction schema and two single-step methods were used for the determination of trace metals. The data of the 1997 period are compared with data from previous studies carried out in the authors' laboratory in the area (1980, 1993) using various analytical techniques, in an attempt to evaluate both the evolution of pollution in the area and the effectiveness of analytical methods. It has been confirmed that a significant part of the pollution load remains in coastal localities in the vicinity of the land based pollution sources, whereas there are also some more remote sites where small polluted particles are transported, deposited and accumulated. The sedimentology regime of the area affects the concentration of metals in a rather complex way depending also on its content of carbonates, organic C and clay minerals. The study of sediment cores has indicated elevated metal concentrations in recent surface sediments. On the other hand, some environmentally positive trends were also observed (i.e. the reduction of mobile metals). A systematic monitoring is needed in the marine environment coupled with some reduction in pollution inputs and integrated management on the coastal zone because the overall hydrological characteristics of the area favour its rapid self-restoration. 相似文献
13.
The aim of this work is to analyze the size-distribution and composition of nanoparticles in a water-extract of a podzol B horizon. AsFlowFFF coupled to ICP–MS and a UV/VIS detector was used for particle fractionation and simultaneous measurement of the composition of the nanoparticles. Detected nanoparticles were organic and mineral particles; the mineral particles were dominated by clay and Fe-(hydr)oxides. Both organic- and inorganic particles contributed to the mobility of Fe, Al, trace metals and P. For Zn, Pb and P respectively 73%, 92% and 72% of the colloidal concentrations were associated with clay minerals. The large contribution of clay particles to the mobility of trace metals and P can be partly explained by the high amount of dispersed clay due to drying, sieving and rewetting of the soil. Inorganic nanoparticles can contribute significantly to the mobility of metals and P in soils. 相似文献
14.
Enrichment of trace metals in surface sediments from the northern part of Point Calimere, SE coast of India 总被引：1，自引：0，他引：1
V. Stephen-Pichaimani M. P. Jonathan S. Srinivasalu N. Rajeshwara-Rao S. P. Mohan 《Environmental Geology》2008,55(8):1811-1819
This study deals with the geochemical nature of distribution, enrichment of total trace metals (Fe, Mn, Cr, Cu, Ni, Co, Pb,
Zn, Cd) in bulk sediments and its association with sediment texture, carbonates and organic carbon. Sixty surface sediment
samples were collected during two different seasons in 2002 and 2003 along the coastal regions in three transects from Nagapattinam
town, north of Point Calimere in southeast coast of India. The sediments are mostly sandy silt and are dominated by the carbonate
content. Organic carbon distribution indicates that they are brought in by the minor river input. Enrichment of trace metals
is clearly identified by the domination of Pb, Zn, Cd with high values than the average crustal values and comparison of trace
metals from other coastal regions in the southeast coast of India. Statistical analysis clearly indicates that Fe and Mn control
the distribution of trace metals and are concentrated in the finer particles and organic carbon fraction. The increase in
concentration signifies the need for regular monitoring of the offshore coastal region in southeast coast of India which was
recently destroyed by the 2004 December tsunami event, and which is also located near the Sethu Samuthram Ship Canal Project. 相似文献
15.
概要地回顾了近年来国内外湖泊沉积物中重金属环境污染方面的研究成果,介绍了湖相沉积物重金属研究的主要内容、方法和可能的发展方向。认为就重金属成因方面应加强区分其主要来源是岩石和矿物风化的碎屑产物、大气降尘、人类活动等的研究;重金属污染方面更应重视污染物质的生物有效性、迁移转化机理和重金属“二次污染”的研究;研究手段上,注重运用同位素示踪与定年技术来研究重金属的来源和污染历史,应用高分辨率沉积物钻心研究环境的变迁。最后提出加强多学科的综合研究,建立中国湖泊基准数据库,为探讨湖泊湿地的可持续发展提供依据。 相似文献
16.
山东半岛典型海岸带多环芳烃分布特征、来源解析及风险评价 总被引：1，自引：0，他引：1
山东半岛海岸带面临着各类复杂的环境问题,尤其是受到了多环芳烃(PAHs)等持久性有机物的污染,本文研究了整个山东半岛典型海岸带62个站点表层沉积物中PAHs的含量及其分布特征,并对其来源和潜在风险进行解析与评价。研究表明,该地区表层沉积物中16种PAHs总含量为0.06~3191.40 ng/g(平均值262.08 ng/g),与国内外海岸带相比,山东半岛海岸带表层沉积物中PAHs整体污染状况处于较低水平,但个别站点的PAHs含量偏高。运用特征比值法、相关性分析及主成分分析法解析研究区PAHs主要来源为木柴、煤炭、油类的燃烧以及油类泄露的联合作用。采用效应区间低值法(ERL)和中值法(ERM)对PAHs进行生态风险评价,结果表明莱州湾周边所有站点及威海、青岛周边个别站点苊、芴浓度位于ERL值与ERM值之间,但多数站点对生态环境潜在负面效应很小。山东半岛典型海岸带中PAHs对生物的毒副作用尚在安全可控范围内,极少对生态环境产生负面效应。 相似文献
17.
Maryam Ghazanfari Shabankareh Hakimeh Amanipoor Sedigheh Battaleb-Looie Javad Dravishi Khatooni 《Environmental Earth Sciences》2018,77(3):101
Heavy metal accumulation in sediments is important even at low levels due to their irresolvable character and harmful effects. Therefore, contamination of creeks, especially their sediments, is highly important for scientific communities. This study investigates the relationship between heavy metal accumulation and some physicochemical parameters of sediments (pH, EC, calcium carbonate, texture, specific gravity, density, porosity and percentage of organic matter) in a stretch of Musa Creek beaches. The results showed that the studied sediments are extremely salty and have slight variations in terms of pH. Although there are mostly clay-sized sediments in the studied area, their mineralogical composition contains calcite with smaller amounts of dolomite, aragonite and halite minerals. The correlation between each of the parameters and heavy metal concentration was modeled using OLS regression. Cr, Ni, Zn and Pb concentrations are positively correlated with each other and inversely correlated with Cd. The accumulation of heavy metals is directly related to parameters such as EC, organic matter, clay and silt, specific gravity and porosity; it is negatively related to calcium carbonate, sand and density parameters. Owing to slight variations, the pH parameter lacks any significant correlation with heavy metal concentrations. 相似文献
18.
Changes in organic materials preserved within sediments of Saginaw Bay deposited over the past two centuries record corresponding
periods in the environmental history of this part of Lake Huron and its watershed. Sediments deposited since 1940 show an
increasingly greater input of aquatic organic matter in response to accelerating cultural eutrophication of Saginaw Bay. Concentrations
of fatty acids, sterols, fatty alcohols, and aliphatic hydrocarbons are higher in these modern sediments than in deeper ones.
Molecular distributions of these geolipids reflect less aquatic material deeper in the sediments. Prior to 1875, sediment
organic matter appears to be diluted by mineral matter from enhanced erosion caused by clearing of the watershed for farming
and settlement. During this period there is better preservation of carbonate minerals due to quicker burial. Since 1875, petroleum
components comprise over 90% of the total aliphatic hydrocarbon content of these sediments, reflecting the advent and continued
existence of chronic, low-level petroleum contamination of this part of the Great Lakes. 相似文献
19.
The purpose of this study was to determine and assess the concentrations of trace metals in surface seawaters and sediments
from different coastal habitats of the Red Sea coast of Yemen. Surface seawater and sediment samples were collected, treated
and analyzed for cadmium, cobalt, manganese, chromium, lead, iron, nickel, copper, zinc and vanadium by the atomic absorption
spectrometric analysis. The concentrations were high for cadmium, cobalt and lead and low or consistent with the natural background
concentrations for the rest of the metals. However, the coastal habitats of the Red Sea coast of Yemen are still considered
unpolluted, it is concluded that the cadmium cobalt and lead levels in surface seawaters are high and could have negative
effects on marine life of the sites. Further studies are needed to characterize the sources fate, biogeochemical processes
and impacts of these trace metals on coastal habitats and marine life of the region. 相似文献
20.