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1.
在综合考虑深圳市城市功能区分异特征的基础上,进行全市表层土壤系统采样,全面监测土壤表层8种重金属元素污染状况,分析不同重金属元素含量的统计学特征,探讨不同城市功能区对土壤表层重金属污染的影响,采用内梅罗指数和潜在生态危害指数评估不同重金属元素和不同城市功能区的生态风险水平,分别进行基于两种方法的全市重金属污染生态风险分区。结果表明: 1)深圳市土壤表层的Mn、Ni、Cr和Pb 4种元素受人为活动的影响程度较低,Cd、Zn、Cu和As 4类元素受人为活动影响较大。地表环境约束因素背景下的高强度城市化和工业化过程,是各种重金属污染区域分异和功能区分异的决定性因素。2)深圳市土壤重金属污染风险较高的重金属元素为Cd、Zn、Cu和Pb,特别是Pb污染问题尤为突出,必须加强管控工作。深圳市总体土壤表层重金属污染风险水平高于国内相关城市,需要引起足够重视。3)内梅罗指数法和潜在生态危害指数法的侧重点不同,在单一重金属元素风险判断、不同城市功能区生态风险的总体评价,以及市域土壤重金属污染生态风险分级评价方面结果差异较大,组合使用效果更好。  相似文献   

2.
藓袋法监测铜陵市大气重金属污染的研究   总被引:5,自引:0,他引:5  
目的:用藓袋法监测铜陵市大气重金属(cu、Cd、Cr、Pb、Zn)污染状况.方法:选取铜陵市的铜陵一冶、铜陵二冶、长江快速通道、凤凰山铜矿区和居民区5个监测点,以采自黄山的大灰藓(Hypnum plumaeforme)为材料,用尼龙筛网(网眼2.0 mm×2.0 mm)做成15.5 cm×5.5 cm的矩形袋子,每袋放3 g,2007年3月22日悬挂于各监测点,完全暴露在空气中,2个月后取回,采用原子吸收光谱法对样品中Cu、Cd、Cr、Pb、Zn等重金属元素含量进行测定.结果:Cu、Cd、Cr、Pb、Zn在5个监测点的含量范围依次为24.43 mg/kg~326.29 mg/kg,0.48mg/ks~4.11 mg/kg,1.72mg/kg~5.74 mg/kg,21.06 mg/kg~85.88 mg/kg,96.61 mg/ks~219.72 mg/kg;单一重金属污染指数值范围依次是:2.76~36.92,0.55~4.73,1.46~4.87,0.52~2.13,1.40~4.16.结论:利用藓袋法能有效的监测大气重金属污染,铜陵市Cu污染最严重,重金属在各监测点的污染程度是铜陵一冶>铜陵二冶>长江快速通道>凤凰山铜矿区>居民区,有色金属冶炼工业是铜陵市最主要的污染源,交通运输对大气重金属污染也日趋严重.  相似文献   

3.
以南京市常见行道树二球悬铃木为试材,研究了交通繁忙区和相对清洁区道路两边悬铃木叶内6种重金属元素的亚细胞分布及其区隔化效应.结果显示:交通污染区悬铃木叶内各亚细胞组分中Cr、Cu、Ni、Pb和Zn 5种重金属元素的含量均明显高于对照区,交通空气污染是影响其含量增加的主要原因之一.相对清洁区和交通污染区5种重金属元素在悬铃木叶片、叶柄的细胞壁组分中含量最高,胞外隔离系数和污染指数均大于0.900,细胞壁是大气重金属元素重要的吸滞器官,并对重金属有明显的阻隔效应;胞内细胞器对Pb和Cu的隔离系数和污染指数最大,细胞器双层膜能在一定程度上抵御重金属元素进入细胞内.悬铃木叶片和叶柄亚细胞组分的污染指数表现为胞质组分>细胞壁组分>细胞器组分,即包括液泡液在内的胞质组分是囤积重金属元素的场所.研究表明,悬铃木叶片、叶柄各亚细胞组分对重金属均有不同程度的累积能力,叶内胞质组分的囤积作用以及细胞壁、质膜与细胞器双层膜的区隔化作用可能是悬铃木叶解除重金属元素毒害的重要原因.  相似文献   

4.
重金属易在大气细颗粒物中富集,经呼吸道进入人体肺泡沉积,危害人类健康。该研究以南京市香樟树皮为对象,选取文教区、交通区、工业区、风景区和商业区5个功能区,探究了不同季节香樟树皮中重金属Cr、Pb、Cu和Zn含量的分布特征,比较了树皮和叶面颗粒物中不同重金属含量的空间分布差异。结果表明:南京市商业区和工业区重金属污染较严重。不同功能区香樟树皮重金属含量具时空分布差异,树皮中重金属含量基本呈秋季冬季春季夏季的季节变化特征,各功能区重金属含量表现为商业区(CA)文教区(CEA)≈工业区(TA)交通区(IA)风景区(SA)。与树皮相比,叶面颗粒物重金属含量较高,商业区叶面颗粒物重金属含量最高,风景区含量最低。经Pearson相关性分析,工业区和文教区香樟树皮中Cr元素具显著相关性(P0.05),Cu与Zn相互对应呈显著相关,表明这两种元素可能具有相似来源;工业区和交通区树皮中Pb具极显著相关性(P0.01)。植物监测可以指示和预测大气重金属污染水平,能反映地区污染情况。  相似文献   

5.
陕西省主要蔬菜产区蔬菜重金属污染状况分析与评价   总被引:7,自引:0,他引:7  
以GB18406.1-2001无公害蔬菜标准为评价依据.对陕西省8个蔬菜主产区的127个蔬菜样品中汞、砷、铅、镉和铬5种重金属污染状况进行分析评价。结果表明,陕西省主要蔬菜产区蔬菜重金属污染以铅污染为主。茄果类和瓜菜类蔬菜铅污染严重,绿叶类蔬菜铅污染相对较轻.其它4种重金属污染未超过国家标准,其中各产区均未检出镉。铅污染程度的大小顺序足成阳秦都〉宝鸡岐山蔡家坡〉汉中汉台〉渭南临渭。成阳泾阳、宝鸡太白、汉中城固、渭南大荔蔬菜产区5种蓖金瞒均未超标.具备发展无公害蔬菜生产基地条件。  相似文献   

6.
石油降解菌的分离鉴定及石油污染土壤的细菌多样性   总被引:19,自引:0,他引:19  
从石油污染的土壤中分离筛选到28株石油降解菌,经鉴定分别为短杆菌属、假单胞菌属、邻单胞菌属和微球菌属;对4个石油不同程度污染的土壤样品中嗜油微生物分布状况进行分析,发现污染严重的土壤样品中嗜油菌的数量相对较多;用聚合酶链式反应(PCR)、变性梯度凝胶电泳(DGGE)和切胶测序相结合的方法对4个土壤样品中的细菌多样性进行分析,结果显示在受污染的土壤中,My cobacterium和B acillus在污染程度较低的样品中分布的较为集中,F lavobacterium和A zosp ira在污染程度较高的样品中丰度较高。属于B eta p roteobacterium类群的细菌在受污染的土壤中占有优势,同时还有一些不可培养的菌群存在。气质联用(GC-M S)分析结果表明石油污染程度及污染物中芳香烃类的含量对细菌多样性有着显著影响。在石油污染程度高,芳香烃类含量高的样品中细菌的多样性相对较低。  相似文献   

7.
湖南柿竹园矿区土壤重金属含量及植物吸收特征   总被引:54,自引:1,他引:53  
矿区重金属污染十分严重,寻找和发现适合当地气候与土壤条件的重金属耐性植物是矿区植被恢复和污染土壤修复的前提。对我国湖南柿竹园有色金属矿区调查发现,该地区选矿厂的重金属污染问题普遍比尾砂库严重。选矿厂土壤砷、镉、铅、锌严重超标,尾砂库周围也受到不同程度的重金属污染。土壤重金属胁迫效应影响着植物物种分布,选矿厂物种分布较少,相比之下尾砂库的植物多样性较为丰富。柿竹园矿区植物对重金属的吸收表现为富集型(如蜈蚣草Pteris Vittata L .和苎麻Boehmerianivea (L .) Gaud.)、根部囤积型(如攀倒甑Patrinia villosa和木贼Equisetum hyemale)和规避型(如蔓出卷柏Selaginelladavidii Franch和芒草Miscanthus sinensis Andlerss)等3种类型。  相似文献   

8.
以交通繁忙区(污染点)和相对清洁区(对照点)道路两侧的二球悬铃木〔Platanus acerifolia ( Ait.) Willd.〕为研究对象,测定了不同器官(包括主干、老树皮、2年生枝条、1年生枝条、腋芽、叶片和果实)中Cu、Ni、Pb和Zn的含量,并对污染点二球悬铃木各器官中4种重金属元素的累积量和污染指数及二者的分布比例进行分析。结果表明:二球悬铃木体内重金属元素的含量因样点、器官及元素的不同而呈现不同的变化规律,污染点4种重金属元素的累积量及其分布比例、污染指数及其分布比例则因器官和元素的不同而有明显差异。总体上看,污染点各器官的Cu、Ni、Pb和Zn的含量均高于对照点且差异显著(P<0.05);4种重金属元素相比较,均以Zn含量最高,Cu含量次之,而Ni和Pb含量则较低;在不同器官中同一重金属元素的含量也有明显差异,其中,Cu、Ni和Zn含量均在腋芽中最高,Pb含量在2年生枝条中最高。4种重金属元素的累积量及其分布比例均在叶片中最高,在老树皮中次之,在1年生枝条、2年生枝条和腋芽中均较低;而4种重金属元素的污染指数及其分布比例则在老树皮中最高,在叶片中次之。研究结果显示:二球悬铃木各器官对空气中的重金属元素均有一定的吸滞能力,并且叶片和老树皮的吸滞能力明显优于其他器官。  相似文献   

9.
太湖地区水稻土的健康质量问题及调控对策   总被引:9,自引:2,他引:7  
从可持续生产安全、营养农产品角度 ,比较系统地阐述了土壤健康质量的概念和内涵 .同时根据土壤健康质量的概念 ,对太湖地区 13个省市级水稻丰产示范方及其灌溉河流淤泥进行了调查 .结果表明 ,太湖地区水稻土N、P含量相对较高 ,但引起面源污染的可能性较小 ,同样水稻土中的重金属含量基本上在环境背景值范围内 ,但点源污染不可忽视 .DDT和六六六的残留也在标准允许范围内 ,生命有益元素Se处于相对缺乏程度 .然而 ,由于乡镇企业的发展 ,三废的肆意排放 ,灌溉河流的富营养化及重金属污染极为严重 .部分河流淤泥中重金属Cu和Zn的含量分别高达 5 4和 7 2mg·kg-1.针对上述情况及发展趋势 ,提出了一些相应的主要控制措施 .  相似文献   

10.
为了解瓯江下游流域及沿岸城郊入江河流沉积物中重金属的污染特征, 对瓯江流域下游及温州城区河流43个表层沉积物中Cr、Co、Ni、Cu、Zn、As 和Pb 共7 种重金属元素的含量特征进行分析, 比较了城郊与城区、城区入江口与城区内部之间河流沉积物重金属含量的特征及差异并探讨其污染来源。结果表明: 沉积物中7 种重金属元素的含量由高到低依次为: Zn>Cr>Cu>Ni>Pb>Co>As, 与浙江省土壤背景值相比, 7 种重金属的平均含量超标1.5-4.9 倍,各种重金属的污染程度依次为: Co>Ni>Cr>Zn>As>Cu>Pb, 综合污染程度已达到警戒线等级。来源分析表明, 重金属元素Cu、Zn、Pb 和Cr 主要来自于工业污水排放及船舶交通等人类活动, Co 和As 主要来自于工业及农业生产活动, Ni主要来自于以工业为主的排污污染。潜在生态风险系数Eri 评价结果显示, 7 种重金属潜在生态风险大小为:Co>As>Cu>Ni>Pb>Cr>Zn, Co 元素处于较强生态风险等级; 潜在生态风险指数RI 介于72.05-107.80 之间, 其中55.5%的样点处于较强生态风险水平, 44.4%为中等生态风险水平, 研究区整体处于较强生态风险水平。  相似文献   

11.
The objective of this study was to analyse the effect of the continuously increasing anthropogenic activities around Riyadh, Saudi Arabia on the accumulation of heavy metals in leguminous crops. This study determined whether four legume crops, Pisum sativum L., Vicia faba L., Glycine max and Vigna sinensis, could accumulate the heavy metals Cu, Mn, Pb and Zn in their leaves, pods and grains during the summer when grown under conditions with ambient air pollution from heavy traffic and industrial activities in Riyadh, Saudi Arabia. The effect of the air pollution was examined by quantifying the protein and trace element Cu, Mn, Pb and Zn concentrations in the leaves, pods and grains of the four plant species. Analysis of the results indicated that air pollution significantly increased the heavy metal concentrations in the leaves, pods and grains. Toxic concentrations of the heavy metals were found in the plants grown at L3, L4 and L5. In conclusion, the air pollution increases as the traffic, industrial activities and population density increase.  相似文献   

12.
A simple apparatus for in situ use of the cage culture technique for growing planktonic algae has been developed and used to follow growth and metal uptake of three diatoms in two Norwegian fjords polluted by heavy metals. Continuous pumping of sea water through a chelating resin and continuous water sampling was used to obtain average values for dissolved and particulate heavy metal content at the various test sites. The metals investigated (zinc, copper, lead, cadmium, and mercury) showed differences in the proportion of dissolved to particulate fractions.The three species of diatoms tested gave systematic growth responses to heavy metal pollution in the moderately polluted fjord; one alga died, one showed reduced growth rate at the more contaminated site compared with those at less polluted sites, while the most tolerant alga was apparently not affected. In the heavily polluted fjord only the most tolerant alga survived, showing decreasing growth rate with increasing pollution.Uptake of heavy metals increased generally with increasing heavy metal content in the sea water. The contents in the algae grown in the most polluted fjord were much higher than those obtained in the less polluted fjord, which were higher than the contents reported for algae from non-contaminated areas.  相似文献   

13.
Airborne metal deposition in the major urban and the industrial districts of Kocaeli was monitored using Xanthoria parietina lichen specimen as a biomonitoring organism. Lichen samples were analyzed for Al, As, Co, Cd, Cu, Fe, Hg, Mn, Ni, Pb, Ti, Tl, V and Zn contents to determine the relationship between the potential pollutant sources in the region and the degree of airborne metal deposition. Results showed that airborne metal deposition in the Kocaeli province was widespread and environmental alteration was serious near the industrial facilities. Mean metal concentrations of lichen samples in the industrial district (Dilovası) of Kocaeli were two to seven folds higher than those in the urban districts of Kocaeli: Mn (7), Pb–Cd–Zn (6), Fe–Ni–Cu (3) and Al–Co–Ti–Hg–As–V (2). Environmental alteration in Dilovası region was severe in terms of all metals analyzed. Cluster analysis showed that metal industry (iron–steel, aluminum, zinc) in Dilovası, fossil fuel combustion processes related to the industry and power plant and heavy traffic contributed significantly to the metal emission in Dilovası region. Airborne metal deposition in the urban districts of Kocaeli was high especially around the coal-fired cement plant in Hereke and petroleum refinery in Körfez. Fossil fuel combustion and traffic emission were among the important sources of airborne metals in the urban–suburban districts.  相似文献   

14.
Abstract

Heavy metal pollution in the atmosphere is a major environmental problem, which has important impacts on ecosystems and human health. In this study, the atmospheric deposition of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn) in Suqian, China, was investigated by using the moss Haplocladium microphyllum as a bioindicator. The survey was carried out during the summer of 2017 at 40 homogenously distributed sampling sites. Cr, Cu, Ni, Pb, V, and Zn were analyzed by inductively coupled plasma atomic emission spectrometry, and Cd was analyzed by inductively coupled plasma mass spectrometry. Wide variations in heavy metals (Cd, Pb, and Zn) indicated that the concentrations of elements are influenced by local emission sources. Spatial distribution maps of the elements were constructed using geographic information system technology. The pollution load index showed that the study area was moderately polluted to unpolluted. Significant positive correlations (p?<?.01) and weak positive correlations (p?<?.05) were identified among some of the elements, indicating that they originated from common sources. A principal component analysis classified the heavy metals into natural and anthropogenic sources, and identified four primary sources: nature soil dust, industry activities, traffic emission, and agricultural activities.  相似文献   

15.
This study investigates the distribution of heavy metals in the suspended particulate matter and the sediments of Kavala Gulf, located in Northern Greece. Particulate trace metals were determined in accordance to water column physicochemical parameters. Metals in sediments were related to the textural characteristics, the organic matter, and carbonate contents of surficial sediments. Results illustrated that the diverse human coastal activities influence the distribution of particulate and sediment metal concentrations, since lower trace metal levels were detected along the western (tourism) and eastern (aquaculture) coast, while increased values were observed at the central (urban and industrial). Overall, particulate metals show moderately low levels compared to other similar sites, with the exception of Ni and Cd depicting local peaks along the industrial coastal zone. Significantly increased levels for particulate lead (123.1 μg/g) and chromium (113.9 μg/g) were detected at the sites near the industrial zone. Direct effluents from a fertilizer plant appeared responsible for the increased Pb, Cr, and Cd levels, while the increased values in Zn, Cu, and Hg appear related to phosphogypsum leaching. Sediment contamination assessment indicated that the Kavala Gulf is characterized by clean to marginally polluted sediments, with moderately severe pollution levels along the urban coastline.  相似文献   

16.
Summary Environmental pollution by toxic metals is widespread in urban areas. In contrast to many industrialized sites, however, metal pollution in most urban regions occurs at low or moderately elevated levels. Reliable criteria of environmental quality have therefore to be established, with the consequence that there is an increasing need for sensitive monitoring of pollution. In this present study, the isopod species Porcellio scaber was used as a bioindicator of lead and cadmium pollution in Innsbruck, Austria. During May 1988, isopods were collected at 356 points over the whole city area; lead and cadmium in whole animals were measured using flame atomic absorption spectrophotometry. Lead and cadmium contamination of urban districts were correlated with traffic density, the only exception being higher cadmium contamination of one district in which several factories are situated. Concentrations of lead, but not of cadmium, increased along the main arterial roads with increasing traffic density and with decreasing distance from the city centre. On a large scale, concentrations of lead and cadmium increased in the direction of the prevailing wind, from south-west to north-east. On a small scale, the variability of metal concentrations can be explained by the irregular distribution of active business centres, by different degrees of contamination between exposed and non-exposed sites, and by contamination gradients depending on wind direction. Compared to highly polluted sites around industrial factories and metal smelting works, lead contamination in Innsbruck can be considered as moderately elevated, whereas cadmium contamination is low.  相似文献   

17.
Summary The concentrations of heavy metals, including zinc, cadmium, and copper were studied in the xylem rings of Pinus sylvestris trees and in the soil of three heavily polluted sites and one non-polluted site. There was a high correlation between the concentration of heavy metals in the soil and recently produced xylem rings. However, the initiation of industrial pollution did not abruptly increase heavy metal concentrations in the xylem rings. There was a high correlation between the zinc content of trees growing near a zinc smelter and the values obtained by other investigators for pine trees growing on the same site.  相似文献   

18.
Concentrations of Pb, Zn, Cd, Ni, Cu, Cr, and Mn were determined to assess the impact of automobiles on heavy metal contamination of roadside soil. Soil samples at four polluted sites and a control site were collected at a depth of 0, 2, 5, 10, 15, 20, 30?cm. A comparison of elemental levels between polluted and control sites exhibited exceptionally higher concentrations at the former sites. The Pb levels in polluted sites varied from 70 to 280.5?µgg?1and it rapidly decreased with depth. Similarly, mean concentrations of Zn, Cd, Ni, Cu, Cr, and Mn were significantly higher at polluted sites and followed a decreasing trend with the increase in depth. Correlation coefficients between heavy metals and traffic density were positively significant except for nickel. Profile samples showed that Pb, Zn, Cd, Cu, and Mn were largely concentrated in the top 5?cm confirming airborne contamination. The vertical movement and partitioning of metals, except Ni and Cr, exhibited predominant association with soil pH and organic carbon. The results have been presented using Heavy Metal Index.  相似文献   

19.
Atmospheric pollution has become a major problem for modern societies owing to its fatal effects on both human health and ecosystems. We studied the relationships of nitrogen dioxide atmospheric pollution and metal trace elements contained in atmospheric particles which were accumulated in bryophytes to microbial communities of bryophytes at three differently polluted sites in France (rural, urban, and industrial) over an 8-month period. The analysis of bryophytes showed an accumulation of Cr and Fe at the rural site; Cr, Fe, Zn, Cu, Al, and Pb at the urban site; and Fe, Cr, Pb, Al, Sr, Cu, and Zn at the industrial site. During this study, the structure of the microbial communities which is characterized by biomasses of microbial groups evolved differently according to the site. Microalgae, bacteria, rotifers, and testate amoebae biomasses were significantly higher in the rural site. Cyanobacteria biomass was significantly higher at the industrial site. Fungal and ciliate biomasses were significantly higher at the urban and industrial sites for the winter period and higher at the rural site for the spring period. The redundancy analysis showed that the physico-chemical variables ([NO2], relative humidity, temperature, and site) and the trace elements which were accumulated in bryophytes ([Cu], [Sr], [Pb]) explained 69.3% of the variance in the microbial community data. Moreover, our results suggest that microbial communities are potential biomonitors of atmospheric pollution. Further research is needed to understand the causal relationship underlined by the observed patterns.  相似文献   

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