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1.
Spheroidal carbonaceous particles (SCPs) from the sediments of 48 Irish lakes were enumerated and characterised according to fuel type. The concentration of metals was determined in the surface sediments and in selected mosses from the catchments of these lakes. Generally the metal concentrations in both the surface sediments and mosses were consistent with background levels found in the remote parts of Europe. Where higher metal concentrations occurred these could often be accounted for by local geochemical sources. SCP levels in the sediments of the selected lakes along the east coast were of sufficient magnitude to suggest a transboundary influence notwithstanding local sources. SCP characterisation also suggests the influence of emissions in Northern Ireland on deposition, particularly in the north-west of Ireland. There was reasonable correlation between the concentration of oil particles in the surface sediments and vanadium, but not with nickel, in mosses. SCP concentrations were not correlated with measured physical characteristics of the lakes. The level of deposition indicated is not likely to have a significant impact on human health over and above the damaging effects of urban dwelling but the adverse impact of this deposition on acid-sensitive surface waters in Ireland has been recorded.  相似文献   

2.
Rose  N.L.  Harlock  S. 《Water, air, and soil pollution》1998,106(3-4):287-308
Spheroidal carbonaceous particles (SCP) and trace metals (Cd, Cu, Pb, Ni, V and Zn) were analysed from 75 lake surface sediments across the UK. Trace metals were additionally analysed from catchment mosses (Hylocomium splendens and Pleurozium schreberi) from 43 of the sites but were absent from the remainder. Spatial distribution of SCP concentration and trace metal concentrations in sediments and mosses showed good agreement with each other and with known emission sources. Particles were allocated to their fuel-type and spatial trends in these data showed good agreement with potential sources. High areas of oil particle deposition were identified in the south-east of England, Merseyside, Galloway / Northern Ireland, the Firth of Forth and eastern Scotland. Oil SCP concentrations showed good agreement with Ni and V concentrations in mosses suggesting an atmospheric source for these metals from the combustion of this fuel. Characterised SCP trends also showed good agreement with predictions from models such as HARM and EMEP. Most high deposition areas of metals and particles were found to coincide with population centres suggesting a possible impact on human health.  相似文献   

3.
Fott  J.  Vukic  J.  Rose  N.L. 《Water, air, and soil pollution》1998,106(3-4):241-261
As a part of the FLAME research project funded by the EU COPERNICUS programme (1994-1996) samples of surface sediments were taken from 31 man-made lakes and one natural lake in the Czech Republic. The sites differ considerably in their altitude, area, catchment, depth, retention time, trophic status, and in parameters of local air pollution. The samples were analysed for concentration of spheroidal carbonaceous particles (SCP, numbers per gram dry mass of sediment), a characteristic component of industrial fly-ash. The extracted carbonaceous particles were allocated according to the fuel-types combusted throughout Europe (coal, oil, brown coal, peat, oil shale) using particle chemistries derived by energy dispersive spectroscopy (EDS). Trace metals were also analysed in the surface sediments as were mosses sampled at the study sites. The main objectives of the study were (i) to look for factors determining SCP concentrations in surface sediments of lakes, with special emphasis on the distribution of large fossil-fuel combustion sources (ii) to compare fuel-type allocation of carbonaceous particles with combustion of these fuels within the country, (iii) to look for trends in spatial distribution of trace metals and (iv) to characterize the impact of airborne particles from these sources on environmental and human health. The SCP concentrations show little or no relation to air-pollution parameters on a small scale, although some large-scale effects are evident. A good relationship was, however, found to site characteristics such as altitude and lake area : catchment area. The reason, why this relationship is more apparent from our dataset than from any other study published so far, is likely to be based on the high variation in the physical parameters (altitude, lake and catchment area) of the sites under study. The distribution of particles attributed to brown coal combustion are in good agreement with the distribution of major air pollution sources across the country but the fraction of particles attributed to coal seems to be overestimated by the present technique. The distribution of trace metals in surface sediments are also in agreement with expected sources. The usefulness of SCP concentrations as indicators of stress to human and environmental health is briefly discussed.  相似文献   

4.
为判识湖泊沉积物中重金属的地球化学行为特征及其控制因素,以包头市南海湖为研究对象,采用连续提取法,系统开展了沉积物中生物有效态重金属的分布研究。结果表明,表层沉积物中重金属生物有效态(前4态之和)的平均比例序列为Cd〉Pb〉Zn〉Cu;Cu的生物有效态占总量的比例为23%,Pb为75%,Zn为42%,Cd为83%。总体而言,表层沉积物中Cd和Pb的潜在危害性最大。湖心区、西南和东北部湖区为表层沉积物中Cu、Pb和Zn的生物有效态含量高值区,Cd仅在西南湖区表现高值。有机物结合态为沉积物柱芯中Cu和Cd生物有效态的主导形态,铁锰氧化物结合态为Pb和Zn生物有效态的主导形态。强还原性条件下,沉积物中以铁锰氧化物结合态为主导形态的Pb、Zn、Cd有一定的潜在风险,Cu的潜在危害较小。与黄河沉积物重金属形态百分比的对比分析表明,南海湖沉积物对重金属的固定能力更强。  相似文献   

5.
巢湖表层沉积物重金属的分布特征及生物有效性   总被引:2,自引:0,他引:2  
为分析沉积物中重金属的分布特征、相互关系及其可能来源,以安徽巢湖表层沉积物为研究对象,利用原子吸收分光光度法(AAS)测定5种重金属(铅、铜、镍、锌、镉)总量和同步浸提重金属(SEM)含量,同时测定酸可挥发性硫化物、总氮、总磷、总有机碳等多种指标,利用低影响程度(ER-L)和中影响程度(ER-M)基准值,[∑SEM]/[AVS]模型和[∑SEM]-[AVS]模型,判断预测表层沉积物中重金属的生物有效性。结果显示:重金属总量在全湖的空间分布不均匀,具有入湖口大于湖心的特征,共8个指标超过ER-L基准值,西湖区各金属总量大于东湖区,两者之间具有显著性差异(P<0.05),全湖[∑SEM]/[AVS]的值在1.097~2.076之间,但[∑SEM]-[AVS]的变化范围为0.127~0.996μmol/g;表明重金属Cu、Cd污染较严重,人为输入影响大,AVS对重金属的束缚作用有重要影响,大部分表层沉积物中的重金属生物有效性低。  相似文献   

6.
The concentrations of Co, Ni, Cu, Zn, Cd, Pb, As, Fe, Mn, and Al were determined in sediments and biota of Songkhla Lake, a shallow coastal lagoon located in southern Thailand. In June 2006, surface sediments were sampled in 44 stations in the three sections of the lake (inner-, middle-, and outer sections). Sediment cores were also sampled in 13 stations in three cross-sections of the lake. In surface sediments, trace and major elements, organic matter, sediment grain size analysis, and sulfides were determined, and in the sediment cores, redox profiles were made. Soil samples were also collected at garbage dumping sites in the vicinity of the lake. In addition, the metal accumulation in two catfish species (Arius maculatus and Osteogeneiosus militaris) and the crustacean (Apseudes sapensis) was also investigated. Trace element concentrations in sediments of Songkhla Lake show that, especially the Outer section of the lake, in particular the sediments at the mouths of the Phawong, U-Taphao, and Samrong Canals are significantly enriched with trace elements due to municipal, agricultural, and industrial discharges entering the lake through the canals. Aluminum-normalized enrichment factors throughout the lake vary from 0.4 to 1.7 for Ni, 0.3 to 3.3 for Cu, 0.2 to 7 for Zn, 0.1 to 14 for As, 1 to 24 for Cd, 0.7 to 6.8 for Pb, and 0.1 to 7.8 for Mn. Correlations between the elements and sediment characteristics show that Cu, Zn, Cd, and Pb are essentially associated with the sulfide fraction; that Ni and Co are predominantly bound to the clay minerals and iron oxy-hydroxides, and that As is principally bound to iron oxy-hydroxides. The accumulation of trace elements between muscle tissue and liver and eggs of A. maculatus and O. militaris is element-specific, but concentrations of trace elements in fish muscle tissue are well within the limits for human consumption.  相似文献   

7.
采样分析了呼伦湖表层沉积物重金属(Cu、Zn、Pb、Cd、Cr、As、Hg)的含量、分布特征及富集状况,分别以现代工业化前正常颗粒沉积物中重金属含量的最高背景值和我国《土壤环境质量标准》的一级自然背景值为参比值,采用瑞典学者Lars Hakanson的潜在生态危害指数法对呼伦湖沉积物中重金属的富集系数和生态危害系数以及各采样点的生态危害指数进行了评价。结果表明,呼伦湖沉积物中7种重金属的空间变异性较小,其中Zn、Cr、Cu的含量变化具有相同趋势,其他元素的含量分布无明显区域变化;以两种背景值为参比得出的重金属污染水平顺序相近,Cd和As为对呼伦湖生态环境具有潜在影响的主要重金属元素。  相似文献   

8.
通过对表层沉积物中重金属及粒度的分析,研究了荣成天鹅湖重金属的含量水平及分布特征,并对沉积物的环境质量进行了初步评价。结果表明,天鹅湖重金属的总体水平较低,Cd、Cr、Pb、Cu、Zn的平均含量均低于国家海洋沉积物I类质量标准,其中Cr和Pb存在轻度污染。Cd、Cr、Ni、Pb、Cu、Zn的含量范围分别为0~0.84、1.75~116.11、1.50~29.06、17.36~27.25、2.00~34.98mg.kg-1和11.48~92.61mg.kg-1,平均含量排序为Zn〉Cr〉Pb〉Cu、Ni〉Cd。天鹅湖重金属的富集状况与沉积物的粒度以及人类活动密切相关,大部分元素的高值区出现在颗粒较细的湖中央以及污染严重的西北部,东南部含量较低。相关分析表明,各重金属之间的相关性较好,其中Cd、Cu、Mn、Zn、Fe间呈高度的正相关,空间分布规律相似;重金属与有机质、粘粒含量呈极显著正相关,而与砂粒呈极显著负相关。根据加拿大制定的沉积物评价标准,天鹅湖沉积物中Cr具有较大的生态危害性。  相似文献   

9.
用采集沉积物样本分析测试的方法,探究了东平湖沉积物中磷的赋存形态特征及其空间分布特征。结果表明,东平湖表层沉积物总磷(TP)含量在500 ~ 812 mg kg?1之间,平均值为 618 mg kg?1,空间分布上表现为湖区中部和西南部含量高、东南部含量低的趋势。沉积物中磷以非活性磷(Ca-P、Res-P)为主,非活性磷与总磷(TP)呈显著正相关(P < 0.01);在总磷中钙结合态磷(Ca-P)占比最高(62.6%),残渣态磷(Res-P)次之(36.2%),活性磷(Ex-P、Al-P、Fe-P)占比最低(1.20%)。靠近湖区边缘的点位沉积物中活性磷占总磷的比例略高于湖区中部点位;表层(0 ~ 4 cm)沉积物中各形态磷含量变化幅度大于下层,随垂直深度增加活性磷含量和非活性磷含量分别表现为下降和上升的变化趋势,这可能与人类活动影响以及沉积物中磷的来源和转化机制不同有关。  相似文献   

10.
Size distributions and concentrations of spheroidal carbonaceous fly-ash particles (SCPs) > 5 μm have been counted in surface sediments from 20 lakes along a 62 km west-east transect in the Bergen area, Norway. Increased concentrations of SCPs are found in lakes immediately downwind, closest to the city. These lakes also have a dominance of larger particles (> 10 μm) than further downwind where smaller particles (5–10 μm) dominate. The pattern of SCPs > 5 μm is compared with a previous study of anthropogenic Pb and SCPs > 3 μm in the same sediments. Along the transect there is a difference in pattern between the concentrations of SCPs > 5 μm and the patterns of anthropogenic Pb and SCPs > 3 μm. The result indicates that increased altitude and rainfall probably explain the increased concentrations of anthropogenic Pb and SCPs > 3μm in the eastern part of the transect. Metals are in the size range for which atmospheric residence times are greatest, whereas particles > 5 μm in diameter are of the size thought to be effectively removed from the atmosphere by sedimentation. This may explain, at least partially, why there is a difference between the pattern of SCPs > 5 μm concentrations and anthropogenic Pb and SCPs > 3 μm concentrations. This study shows that SCPs > 5 μm in lake sediments can potentially provide a better signal of locally-deposited atmospheric pollution than trace elements from the same source. A SCP distribution dominated by large particles (> 10 μm) is found up to 20 km downwind of the city. Within this area, temporal SCP size distribution patterns can help detect local-deposited atmospheric pollution.  相似文献   

11.
对巢湖湖区不同位点的表层沉积物中的Fe、Cr、Pb、Cu、Co、Zn、Ni7种重金属含量进行的分析表明,湖泊沉积物中重金属含量分布呈现一定的区域特征,由于巢湖西半湖靠近合肥市区,大量的工业废水和生活污水通过河道排入巢湖,引起西半湖区中重金属含量高于东半湖区。采用富集因子法和地积累指数法对巢湖沉积物重金属污染现状进行了评价,结果表明,巢湖沉积物中存在Pb、Cu污染,个别地区已相当严重,并呈现沿湖心区至东半湖区逐渐降低趋势。研究表明,两种方法均能对人为污染行为做出较为科学的评价,且两种方法得到的评价结果基本一致。由于重金属元素有很强的毒性,并且能够在食物链中传递,有关部门应及早从流域环境综合规划入手,对重金属污染问题采取有力的控制对策,保护沿湖地区居民免受危害。此外,对巢湖表层沉积物中重金属污染物来源进行了初步分析,据分析结果判断,巢湖沉积物中重金属总量Co、Fe、Cr的来源相似,Zn和Cu的来源相似。  相似文献   

12.
A serious health scare involving thesupply of drinking water to Sydney, Australia hasrecently focussed attention on the environmentalstatus of river catchments of the main reservoir, LakeBurragorang. Although the Coxs River – a majorcatchment of Lake Burragorang – comprises mainlyforests and grazing land, it supports a moderate sizedtown, power stations and coal mines. The heavy metal content of stream-bed sedimentscharacterises environmental impact in this ruralcatchment and sources of contamination. Sediment in acreek flowing through a country town (population 12 000) is markedly enriched in Cr, Pb and Zn (3×, 18×and 52×, respectively) over background, probably dueto a long history of metal-based industry. The highestCu, Pb and Zn concentrations (204, 332 and2460 μg g-1, respectively) in fluvialsediment in the town are, however associated withdischarges from a sewage treatment plant. Twocoal-based power stations in the catchment contributeconsiderable Cu and Ni (maximum concentrations 562 and157 μg g-1, respectively) to ambient fluvialsediments, possibly from cooling towers and coalstorage areas. The highest Co and Cr concentrations(113 and 490 μg g-1) in fluvial sediments ofthis catchment are associated with coal-miningactivities. Selective extraction indicates that about50% of the anthropogenic fraction may bebioavailable, whereas sequential extraction proceduressuggest that <25% is associated with the easilyexchangeable/adsorbed phase.Two dams restrict the migration of heavy metals downthe Coxs River and sediment discharging into LakeBurragorang is low in metals.  相似文献   

13.
天鹅湖泻湖表层沉积物中各形态磷的空间分布特征   总被引:1,自引:0,他引:1  
《土壤通报》2015,(1):127-132
以山东半岛天然泻湖—荣成天鹅湖为研究对象,研究了表层沉积物中总磷、各形态无机磷、有机磷的含量水平及空间分布特征,明确了不同湖区沉积物磷的潜在生物可利用性,并对各形态磷与磷酸酶的相关性进行了分析。结果表明,天鹅湖表层沉积物总磷含量变化在236.9~689.7 mg kg-1之间;在大多数样点,无机磷含量高于有机磷,钙结合态磷是无机磷的主要存在形式。有机磷含量变幅为40.57~198.7 mg kg-1,中等活性和非活性有机磷之和占有机磷总量的90%以上。相关性分析表明,有机磷与无机磷、铁铝结合态磷、总磷呈极显著相关关系,碱性磷酸酶与总磷、有机磷、铁铝结合态磷等呈极显著相关(P0.01)。天鹅湖沉积物的总磷及各形态磷含量存在较大的空间差异性,其中西北部和东北部铁铝结合态磷、生物可利用磷和活性有机磷含量均较高,说明此湖区沉积物中的磷具有较大生物可利用性。  相似文献   

14.
Total topsoil 50th percentile Cu, Pb and Zn concentrations (n?=?491) in the Sydney estuary catchment were 23 ??g?g?1, 60 ??g?g?1 and 108 ??g?g?1, respectively. Nine percent, 6% and 25% of samples were above soil quality guidelines, respectively and mean enrichment was 14, 35 and 29 times above background, respectively. Soils in the south-eastern region of the catchment exhibited highest metal concentrations. The close relationship between soil metal and road network distributions and outcomes of vehicular emissions modelling, strongly suggested vehicular traffic was the primary source of metals to catchment soils. Catchment soil and road dust probably make an important contribution to contamination of the adjacent estuary. The concentration of soil metals followed the land use trend: industrial?>?urban?>?undeveloped areas. A high proportion (mean 45%, 62% and 42%, for Cu, Pb and Zn, respectively) of metals in the soils may be bioavailable.  相似文献   

15.
Toxic metals introduced into aquatic environments by human activities accumulation in sediments. A common notion is that the association of metals with acid volatile sulfides (AVS) affords a mechanism for partitioning metals from water to solid phase, thereby reducing biological availability. However, variation in environmental conditions can mobilize the sediment-bound metal and result in adverse environmental impacts. The AVS levels and the effect of AVS on the fate of Cu, Cd, Zn, Ni in sediments in the the Changjiang River, a suboxic river with sandy bottom sediment and the Donghu Lake, a anoxic lake with muddy sediment in China, were compared through aeration, static adsorption and release experiments in laboratory. Sips isotherm equation, kinetic equation and grade ion exchange theory were used to describe the heavy metal adsorb and release process. The results showed that AVS level in the lake sediment are higher than that of the river. Heavy metals in the overlying water can transfer to sediments incessantly as long as the sediment remains undisturbed. The metal release process is mainly related to AVS oxidation in lake sediment while also related to Org-C and Fe–Mn oxyhydroxide oxidation in river sediment. The effect of sulfides on Zn and Ni is high, followed by Cd, and Cu is easy bound to Org-C. AVS plays a major role in controlling metals activity in lake sediment and its presence increase the adsorption capacity both of the lake and river sediments.  相似文献   

16.
盘龙江口滇池沉积物重金属的分布及污染评价   总被引:10,自引:2,他引:10       下载免费PDF全文
李仁英  杨浩  陈捷  余天应  金峰 《土壤》2006,38(2):186-191
对盘龙江口滇池沉积物重金属的分布进行了研究并对其污染状况进行了评价。结果表明:Cd、Cr、Cu和Zn在表层沉积物中的含量较高(Pb在中层的含量较高),且随采样深度的增加含量递减,这几种元素的含量顺序基本为Zn>Cu>Cr=Pb>Cd。表层沉积物中各元素之间的相关性较差,中层和底层的相关性较好。表层沉积物重金属与颗粒的相关性较差。除底层沉积物中的重金属与有机质达到显著或极显著相关外,表层和中层的相关性都较差。所研究重金属(除Pb外)随与河口距离的增加,含量降低。利用地积累指数对该河口重金属的污染进行评价,发现重金属污染都在中等程度以上,其污染程度顺序为:Cd>Zn>Cu=Pb>Cr,表明盘龙江入滇池口区的沉积物已受到严重污染。  相似文献   

17.
利用TM影像分析巢湖悬沙分布及其原因   总被引:4,自引:0,他引:4  
悬浮泥沙是重要的水质参数之一,其大小直接影响水体透明度、浑浊度、水色等光学性质及水生生态条件,其含量及其动态变化对该区的水下地貌的发展及冲淤变化等具有非常重要的影响。以巢湖为例,利用TM影像分析了巢湖泥沙的空间分布情况,指出巢湖泥沙的来源主要是各入湖河流携带的泥沙,其次是岸坡崩塌物形成的,并结合流域环境背景分析其原因,为巢湖的航道治理、湖区清淤提供了科学依据;最后提出了巢湖水质保护的对策。  相似文献   

18.
In Godavari estuary, the enhanced metal concentration in the sediment is localized, and is accompanied by marked enrichment in organic carbon, Kjeldahl nitrogen, and humic acid. High concentration of organic carbon was observed near the riverside sampling stations. A similar pattern was found for the humic acid concentrations. Relatively high organic carbon content was observed in pre-monsoon/monsoon compared to post-monsoon seasons which can be attributed to higher productivity due to upwelling in the former and landrunoff due to excessive rainfall in the later seasons. The trace metals in the sediments were found to be in the following order of their abundanceFe≥Mn≥Zn≥Pb≥Ni≥Cu≥Cd. In monsoon season relatively high levels of trace metals were reported in surface sediments which are transported by currents. The dominant process controllingthe metal enrichment may be either precipitation of metal-humic acid type of complexes. Our results indicate that in the Godavari estuary, the metal distribution is mainly influenced by sedimentarydynamics, while the contamination effect is very limited.  相似文献   

19.
青海湖典型湿地土壤重金属空间分布特征   总被引:2,自引:0,他引:2  
以青海湖黑马河湿地为研究对象,对湿地土壤重金属铜、锌、铅、铬(Cu,Zn,Pb,Cr)4种元素的空间分布特征进行了研究。结果表明:湿地表层土壤(0—10cm)中,Cu,Cr,Pb和Zn的平均含量分别为16.38±4.95mg/kg,65.46±7.34mg/kg,14.26±4.28mg/kg,46.35±7.27mg/kg。垂直湖岸的水平方向上,Cu,Cr,Pb和Zn的含量高值出现在湿地高水位带以及陆相带,低值出现在湿地水陆过渡带。在土壤剖面方向上,各重金属元素表现出不同的分布特征:Cu呈现出表面聚集现象;Zn随深度变化有明显的淋溶和积聚趋势;Pb含量沿土层剖面纵深分布的特征是先增加后减少;Cr呈显著的表面聚集现象。湿地表层土壤的对比结果显示研究区内土壤环境质量良好。湿地土壤中Cu,Zn,Pb,Cr四种元素之间呈显著正相关,表明本区域重金属具有同源性。  相似文献   

20.
基于达里诺尔湖富营养化日趋严重的现实,开展了湖泊表层沉积物中腐殖质形态空间分布和污染特征研究。结果表明,表层沉积物中腐殖质形态水平分布均表现经向分异特征,胡敏素的分布特征主导了腐殖质的水平分布格局。达里诺尔表层沉积物中胡敏素是腐殖质中的主导形态,占总有机碳的74%~94%,占腐殖质的80%~90%。深水区表层沉积物中松结态胡敏酸和稳结态胡敏酸含量高于浅水区,揭示由水深导致的氧化还原条件是影响胡敏酸分布的因素之一。腐殖质本身矿化率很低,但它能促进其他有机质的矿化,腐殖质形态与总有机碳、有机氮显著相关。达里诺尔湖表层沉积物中有机指数基本为中清洁水平,湖区西南部有机污染较湖区东北部严重,湖区西部有机污染较湖区东部严重。  相似文献   

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