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1.
A field survey of higher terrestrial plants growing on Lanping lead-zinc mine, China were conducted to identify species accumulating exceptionally large concentrations of Pb, Cd, Cu and Zn of 20 samples of 17 plant species. Concentrations of Pb and Zn in soil and in plant were higher than that of Cu and Cd. Significant difference was observed among the average concentrations of four heavy metals in plants (except Cd and Cu) and in soil (except Pb and Zn) (P<0.05). For the enrichment coefficient of the four heavy metals in plant, the order of average was Pbtree>herbaceous, and herbaceous grew in soil with the highest concentrations of four heavy metals. In different areas, the concentrations of Pb, Cd, Cu and Zn in plants and soils and enrichment coefficient were different. Plants in Paomaping had more accumulating ability to Pb, Cd and Zn, and plants in Jinfeng River had more accumulating ability to Cu. Six plant species, i.e. S. cathayana, Lithocarpus dealbatus, L. plyneura, Fargesia dura, Arundinella yunnanensis and R. annae in Paomaping, had high accumulation capacity. R. annae in Paomaping had hyperaccumulating capacity to Pb, Cd and Zn, L. plyneura to Pb and Cd, and S. cathayana to Cd, respectively.  相似文献   

2.
长三角典型城郊农田土壤-浙贝母重金属迁移特征研究   总被引:1,自引:0,他引:1  
城郊生态系统中土壤重金属分布及其在土壤—植物系统的迁移和富集特征是城乡共生体土壤安全研究的热点问题。以典型经济作物浙贝母(Fritillaria thunbergii)为例,基于野外采样和实验分析,对长三角代表性城郊农田中土壤—植物系统重金属的分布、富集和迁移特征开展研究。结果表明:受人类活动的影响,城郊农田土壤中重金属除Cr外,Cu、Zn、As、Cd和Pb的平均含量超过土壤背景值,并且不同重金属在空间分布上表现较高的空间异质性。除Cd和Cr外,浙贝母植株不同部位重金属含量表现为叶、茎显著高于鳞茎,叶中重金属含量可达到鳞茎的5~10倍,表明叶比鳞茎更易富集重金属。重金属迁移系数分析表明,Cr、Cu、Zn、As、Cd和Pb主要富集在浙贝母植株的地上部分,且不同重金属在植株中的迁移和富集能力具有较大的差异。浙贝母地上部分对Cr、As和Pb的富集能力较低,对Cu、Zn和Cd的富集能力相对较强。相比而言,鳞茎对不同重金属的富集能力均较弱,综合污染评价也表明,浙贝母鳞茎中重金属含量并未超过污染标准。  相似文献   

3.
A potential hazard to Beijing was revealed due to the accumulation trend of heavy metals in agricultural soils with sewage irrigation, which results in metal contamination and human exposure risk. Samples including soils and plants were collected to assess the impacts of sewage irrigation on the irrigated farming area of Beijing. Concentrations of the five elements Cd, Cr, Cu, Zn, and Pb were determined in samples to calculate the accumulation factor and to establish a basis for environmental protection and the suitability of sewage irrigation for particular land use in the urban-rural interaction area of Beijing. Using reference values provided by the Beijing Background Research Cooperative Group in the 1970s, the pollution load index (PLI), enrichment factor (EF), and contamination factor (CF) of these metals were calculated. The pollution load indices (sewage irrigation land 3.49) of soils indicated that metal contamination occurred in these sites. The metal enrichment (EF of Cd 1.8, Cr 1.7, Cu 2.3, Zn 2.0, Pb 1.9) and the metal contamination (CF of Cd 2.6, Cr 1.5, Cu 2.0, Zn 1.7, Pb 1.6) showed that the accumulation trend of the five toxic metals increased during the sewage irrigation as compared with the lower reference values than other region in China and world average, and that pollution with Cd, Cu, Zn, and Pb was exacerbated in soils. The distributions of these metals were homogeneous in the irrigation area, but small-scale heterogeneous spatial distribution was observed. Irrigation sources were found to affect heavy metal distributions in soils. It was suggested that heavy metal transfer from soils to plants was a key pathway to human health exposure to metal contamination. However, with the expansion of urban areas in Beijing, soil inhalation and ingestion may become important pathways of human exposure to metal contamination.  相似文献   

4.
Concentrations of silver, cadmium, chromium, iron, manganese, nickel, lead, vanadium, and zinc were determined in dust fallout samples from eight inland locations in Kuwait. Results were used to calculate enrichment factors for metals relative to their abundance in the continental crust using Fe as the conservative element. Five metals (Cu, Cr, Mn, Ni, and V) showed enrichment factors that were approximately unity (1.3–4.7). Higher enrichment factors for the rest (24–421) suggested an anthropogenic contribution for Ag, Cd, Pb, and Zn. However, all metals in dust fallout (except Pb and Zn) showed a degree of enrichment relative to unpolluted marine sediments that was approximately unity, suggesting a substantial aeolian contribution to trace metals in marine surface sediments. Higher enrichments for Pb and Zn probably reflect a larger input from local pollution sources. This is particularly true for lead, the enrichment of which showed a stronger association with the distribution of urban population. Probable contributions of aeolian transport to a band of elevated lead concentrations in marine surface sediments are discussed.  相似文献   

5.
鄱阳湖主要入湖口重金属的分布及潜在风险评价   总被引:4,自引:0,他引:4  
于2011年5月在鄱阳湖的主要入湖口采集了水样和表层沉积物,测定并分析了其中Cu、Zn、Pb、Cd 4种重金属元素的含量和分布。同时采用地积累指数法、潜在生态危害指数法和生态毒性效应等评价方法对沉积物中重金属的污染状况进行了分析评价。结果显示:鄱阳湖主要入湖口水体重金属Cu、Zn、Pb、Cd含量均符合国家渔业水质标准要求,除修河的Pb和信江、饶河入湖口的Cd含量属于国家地表水Ⅱ类水质外,其它所有样地的4种重金属含量均低于国家地表水I类标准限值。沉积物中4种重金属含量均超过鄱阳湖相应背景值且呈积累富集的趋势,其中信江入湖口、饶河入湖口以及三江口已受到重金属的严重污染,潜在生态危害均为中等,而污染最轻的区域为南主湖区。揭示重金属污染程度顺序为Cu>Zn>Pb>Cd;单个重金属潜在生态风险顺序为Cd>Cu>Pb>Zn。进一步的生态毒性效应评价结果表明,虽然鄱阳湖主要入湖口沉积物已经受到重金属污染,但对多数底栖生物未产生明显毒害  相似文献   

6.
Total concentrations and speciation of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in surface sediment samples were correlated with the respective metal measured in the total soft tissue of the green-lipped mussel Perna viridis, collected from water off the west coast of Peninsular Malaysia. The aim of this study is to relate the possible differences in the accumulation patterns of the heavy metals in P. viridis to those in the surface sediment. The sequential extraction technique was employed to fractionate the sediment into 'freely leachable and exchangeable' (EFLE), 'acid-reducible,' 'oxidisable-organic' and 'resistant' fractions. The results showed that significant (P<.05) correlations were observed between Cd in P. viridis and Cd in the sediment (EFLE fraction and total Cd), Cu in P viridis and Cu in the sediment (EFLE and 'acid-reducible' fractions and total Cu) and Pb in P viridis and Pb in the sediment ('oxidisable-organic' fraction and total Pb). No significant correlation (P > .05) was found between Zn in P viridis and all the sediment geochemical fractions of Zn and total Zn in the sediment. This indicated that Zn was possibly regulated from the soft tissue of P. viridis. The present results supported the use of P viridis as a suitable biomonitoring agent for Cd, Cu and Pb.  相似文献   

7.
根据长江口洋山海域表层沉积物监测资料,利用变异系数法和富积系数法,对表层沉积物中重金属的空间波动程度及富积程度进行了分析,并采用Hakanson潜在生态危害指数法对其潜在生态危害程度进行了评价。结果表明:在表层沉积物所监测的重金属中,Pb元素的空间波动程度最高,其它重金属元素的空间波动程度较低,各重金属空间波动程度的顺序依次为Pb>Cd>Hg>Cu>Cr>As>Zn;沉积物中Cu元素的富积程度最高,Pb元素次之,其它重金属元素的富积程度较低,各重金属富积程度的顺序依次为Cu>Pb>Zn>As>Cr>Cd>Hg。潜在生态危害评价结果显示:洋山海域表层沉积物中的重金属对海洋生态系统的潜在生态危害较轻微,均属于轻微潜在生态危害程度,其轻微潜在生态危害程度顺序为Cu>As>Hg>Pb>Cd>Cr>Zn。  相似文献   

8.
鄱阳湖水土环境及其水生维管束植物重金属污染   总被引:23,自引:1,他引:23  
位于鄱阳湖流域乐安河中下游的德兴铜矿,是我国著名的大型铜业基地,是鄱阳湖流域重金属污染的主要来源之一。2003年7月至8月对鄱阳湖部分流域的水质、沉积物、底泥及水生维管束植物等样品的重金属污染进行了研究调查,采用原子吸收分光光度法分别对样品中的Cu、Zn、Pb、Cd等重金属含量进行了测定,并对测定结果进行了评价。研究结果表明,鄱阳湖流域水体中的重金属含量均达到地表水评价标准中的Ⅰ类标准,底泥、土壤等已受到了一定程度的重金属污染。而水生植物对重金属元素都具有不同程度的富集能力,植物对重金属的富集作用与土壤背景值有一定的相关性,土壤中重金属的背景值越高,植物对重金属的富集量也相应增加。  相似文献   

9.
Partitioning of metals in sediments from the Odiel River (Spain)   总被引:3,自引:0,他引:3  
The Odiel River runs through an area known as the Iberian pyrite belt in the province of Huelva in the southwestern corner of the Iberian Peninsula. Its waters are acidic and contain large amounts of heavy metals from erosion and mining activity. In addition, the Odiel River estuary is one of the most industrialized areas in southern Spain and, consequently, receives the discharge of industrial and urban waste. Seventeen sediment samples from the Odiel and its main tributaries were analyzed for this study. The chemical partitioning of metals (Cu, Zn, Cd, Pb, Fe, Ni, Cr and Co) in each sample was determined in four fractions (acid-soluble, reducible, oxidizable and residual). The total content of each of the metals was also determined. The results showed high concentrations of Fe, Cu, Zn, Pb and Cd, undoubtedly as a result of contamination from the mining and industrial activity mentioned above. However, the concentrations of the other metals analyzed were low since there are no sources of pollution by them in the Odiel River. Based on the chemical distribution of metals, we found that Cd, Zn and Cu are the most mobile metals (i.e., metals that can pass easily into the water under changing environmental conditions). Cd is the metal that showed the highest percentages in the acid-soluble fraction (the most labile) and the lowest in the residual fraction. However, Pb, Fe, Cr and Ni are present in the greatest percentages in the residual fraction, which implies that these metals are strongly linked to the sediments.  相似文献   

10.
Bi X  Feng X  Yang Y  Qiu G  Li G  Li F  Liu T  Fu Z  Jin Z 《Environment international》2006,32(7):883-890
Total heavy metal (Cd, Cr, Cu, Pb and Zn) concentrations were evaluated in smelting waste, soil, crop and moss samples collected from the Hezhang artisanal zinc smelting areas, Guizhou, China. Soil samples from the cornfield near the smelting sites contained extremely high Cd (5.8-74 mg kg(-1)), Pb (60-14,000 mg kg(-1)) and Zn (260-16,000 mg kg(-1)) concentrations. Elevated heavy metal concentrations were also found in corn plants and total Pb (0.80-1.5 mg kg(-1)) and Cd (0.05-0.76 mg kg(-1)) concentrations in corn grain have totally or partially exceeded the national guidance limits for foodstuff. Thus, the soil-to-crop transfer of heavy metals might pose a potential health risk to the local residents. Similar to the high heavy metal levels in soil and corn, Cd, Cr, Cu, Pb and Zn concentrations in moss samples collected from the smelting sites ranged from 10 to 110, 10 to 55, 26 to 51, 400 to 1200 and 330 to 1100 mg kg(-1), respectively, exhibiting a local spatial pattern of metals deposition from the atmosphere. Based on examination of Zn/Cd and Pb/Cd ratios of the analyzed samples, we have distinguished between the flue gas dust derived and smelting waste derived metals in different environmental compartments.  相似文献   

11.
Water samples have been collected at the surface and bottom layers at 51 locations throughout Chesapeake Bay. The suspended particulate and dissolved fractions of these samples have been analyzed for Cd, Ce, Co, Cu, Fe, Mn, Mo, Ni, Pb, Sc, Sn, Th, U, and Zn using neutron activation analysis and atomic absorption spectrometry. Special chemical procedures were used to preconcentrate the elements of interest in the dissolved samples and separate them from the salt water matrix. The elemental concentrations observed in the dissolved samples were evaluated by direct comparison to those found in coastal seawater; however, the elemental concentrations in the particulate samples (mass per volume of water) were strongly influenced by the total amount of particulate material suspended in the water at time of collection. A double normalization procedure was used to calculate crustal enrichment factors for each sample, and these enrichment factors provided both a means to observe sample-to-sample variations, and also allowed a crude comparison with the natural levels occurring in the earth's crust.  相似文献   

12.
Studies on toxicities and tolerances of cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn) in the brown alga Isochrysis galbana and in the green-lipped mussel Perna viridis were conducted by short-term bioassays using endpoints growth production and mortality, respectively. The 5-day EC(50) and 24-h LC(50) of these heavy metals were determined in the brown alga and mussel, respectively. The EC(50) values calculated for the alga were 0.74 mg/l for Cd, 0.91 mg/l for Cu, 1.40 mg/l for Pb and 0.60 mg/l for Zn. The LC(50) values for the mussels were 1.53 mg/l for Cd, 0.25 mg/l for Cu, 4.12 mg/l for Pb and 3.20 mg/l for Zn. These LC(50) values were within the concentration ranges as reported by other authors who used P. viridis as the test organism. Based on these EC(50) and LC(50) values, the alga was most sensitive to Zn, followed by Cd, Cu and Pb while the mussel was most sensitive to Cu, followed by Cd, Zn and Pb. Differences in the trophic levels, metal handling strategies, biology and ecology of the primary producer (brown alga) and the primary consumer (mussel) are believed to be the plausible causes for the different toxicities and tolerances of the metals studied.  相似文献   

13.
通过对昆山市14个区镇91个土壤样品中As、Cd、Cr、Cu、Pb、Ni、Hg、Zn 8种重金属测定分析,对该市耕地土壤重金属污染进行评价并进行重金属污染的影响因素分析.结果表明,昆山市耕地土壤存在不同程度的轻微污染,重金属Cd、Cr、Cu、Pb、Hg、Zn均超过国家土壤背景值,旱地、水田中均以Hg污染范围较广、变异系数较大.综合污染指数表现为水田(1.15)>旱地(1.00).区镇耕地重金属污染评价表明千灯、陆扬、石浦、锦溪、石牌处于警戒值之内,蓬朗、周庄、张浦、正仪、周市、巴城、淀山湖、花桥、陆家轻度污染;昆山市耕地土壤中重金属元素均未超过土壤环境基本容量,能够保证作物品质和农业持续发展.同时,研究表明区域重金属轻微污染具有复合污染的特性,Cd、Pb相关性最高(P=0.621 0), Pb与Hg、Cu、Zn、Cu与Cr也有相关性(0.438 7、0.426 0、0.350 9、0.394 0),区域重金属的轻微污染受人为因素影响显著,研究指出应加强对区域优先控制污染物Hg、次优先控制污染物Pb、Cd、Zn、Cu、Cr的控制与治理.  相似文献   

14.
三峡库区中低产土壤重金属含量及其与小麦吸收的关系   总被引:3,自引:0,他引:3  
三峡库区中低产土壤的Hg,As,Cr,Pb,Cu五个重金属含量(除渝北区外),均在国家土壤环境质量标准内,属自然背景值一级标准。Cd和Zn高于全国土壤中的平均含量和背景值含量,属二级标准。土壤的重金属含量与土壤母质类型,pH值,阳离子交换量,有机质,无定形铁和物理性粘粒有关,同时存在一定的地域分布。重庆近郊的土壤所有重金属含量相对较高。土壤重金属的可给态或有效性含量极低,锌和铜不是过量,而是不足。小麦籽粒中As,Cr,Pb,Zn,Cu含量低于国家食品对重金属限量标准和小麦籽粒背景值标准,Hg,Cd含量高于国家规定标准。籽粒中的Cu,Zn含量是小麦茎叶中的2.0-2.2倍,而茎叶中的Hg,Pb,As,Cr,Cd含量明显高于籽粒。  相似文献   

15.
Atmospheric particulate matter (APM) was collected at three sampling sites in Beijing, China, from February to June 1998. The concentrations of rare earth elements (REE) and cobalt (Co), zinc (Zn), copper (Cu), cadmium (Cd) and lead (Pb) in the APM were determined by inductively coupled plasma mass spectrometry (ICP-MS). The results obtained in Beijing, China, were compared to that obtained in Delft, the Netherlands, in 1997. The influence of coal combustion was considered. The results demonstrated that the content of APM, the concentrations of REE and Co, Zn, Cd, Pb in the APM in Beijing, China, were higher than that in Delft, the Netherlands. From the ratios of La to Ce, and La to Sm, which may be used as tracers for the origin of the REE, it is concluded that the origins of REE in China differ from those in the Netherlands.  相似文献   

16.
水体悬移质对重金属吸附规律研究 ——以长江宜昌段为例   总被引:10,自引:0,他引:10  
随着长江三峡工程的建设,上游来水的流速在坝区附近减缓,随江水而下的大量泥沙在此沉淀,将使坝下(长江中下游)水中的悬移质浓度降低、粒径改变 ,从而改变水环境容量。利用长江宜昌江段的周年悬移质样及水样,研究了悬移质对重金属(铜、锌、铅、镉及铬)的吸附特征。结果表明,悬移质对上述金属的吸附可用Freundlich型及Langmuir型等温式较好进行拟合;当较高浓度的金属污染物排入江水后,在吸附及沉淀的共同作用下,浓度明显降低;单位悬移质的吸附量随悬移质浓度降低而上升,但总吸附量降低,从而导致水中的金属污染物的平衡浓度升高。所得结果为预测水环境容量提供了依据。  相似文献   

17.
The contents of Al, Ti, Fe, Cr, Cu, Zn, As, Se, Cd, Pb, and rare earth elements (REEs) were determined in mosses (the hydrophyte Fontinalis antipyretica and the epiphyte Pylaisia polyantha) by the inductively coupled plasma-mass spectrometry (ICP-MS) method. These plants were used for estimating the spatial distribution of heavy metals (HMs) in the basins of small and medium rivers of Vologda and Kostroma oblasts (Russia). It was shown that water mosses are good indicators of REEs and epiphytic mosses, of the pollutant metals Cu, Zn, Se, and Pb. The epiphytic and hydrophytic mosses did not differ in the macroelement (Al, Ti, and Fe) content.  相似文献   

18.
长江(万州段)沉积物中重金属污染生态风险评价   总被引:4,自引:0,他引:4  
对长江万州段沉积物进行采集,用原子吸收光谱法测定了沉积物中的Pb、Cu、Cr、Cd、Zn等重金属的含量,用单因子指数法和Hakanson生态风险指数法评价了沉积物中重金属综合污染效应。结果表明:长江万州段主要的重金属污染因子为Cd,生态风险影响因子顺序为:Cd>Zn>Pb>Cu>Cr。潜在生态风险因子大小顺序为:Cd>Pb>Cu>Zn>Cr,潜在生态风险指数RI平均值为152.35 ,长江万州段大部分断面处于中等潜在生态风险。  相似文献   

19.
Components and quantity of street dust are environmental pollution indicators especially in big cities. Street dust is generally composed of car exhaust gas originated particles and wind-transported particles. Heavy metals, which are found in street dust, such as Pb, Cu, Mn, Zn, Cd and Ni are significant for environmental pollution. According to the kind of vehicle in traffic, quantity and type of heavy metals vary in street dust. The use of leaded gasoline gives a boost to the importance of lead level especially in street dust even at the start of 21st century. These metals possess bioaccumulation property, and the possibility of the amount of these metals reaching a critical value and threatening human health increases the importance of this issue. In this study, street dusts have been collected from E-5 Highway from Topkapi to Avcilar regions that spans about 18 km in Istanbul, Turkey, and Pb, Cu, Mn, Zn, Cd and Ni concentrations have been detected in street dust. Twenty-two street dust samples were taken from a total of 22 different points at previously decided 14 main areas. Analyses were conducted using Leeds Public Analyst method. According to the results of this study, Pb, Cu and Zn concentrations in E-5 Highway between Topkapi and Avcilar region in Istanbul were higher than maximum concentration levels of these heavy metals in normal soil. This situation indicates that there is heavy metal pollution in the inspected area in E-5 Highway in Istanbul.  相似文献   

20.
为揭示城市化、工业化等人为活动对土壤环境质量的影响,选择能反映上海城郊乡梯度差异的中心城区、城郊结合部和远郊,采用地统计学方法对表层土壤样品Cu、Zn、Pb的空间变异结构和分布特征进行了对比分析。结果表明:城市土壤Pb、Cu、Zn的变异系数范围为0.24~0.62,均属中等变异强度。徐汇区土壤Cu、Pb、Zn符合正态分布,闵行区土壤Cu、Pb和Zn符合对数正态分布,奉贤区土壤Zn呈正态分布,土壤Cu、Pb符合对数正态分布。由中心城区到远郊,城市土壤Cu、Pb、Zn的各项统计特征值和变异系数均有较大差异,存在明显的空间分布差异。半方差函数分析结果表明,徐汇区作为中心城区,土壤Cu、Pb、Zn符合球状模型,土壤Cu、Zn具有强烈的空间相关性,土壤Pb具有明显的空间自相关。奉贤区以农业用地为主,土壤Pb符合线性模型,土壤Cu符合高斯模型,土壤Zn符合指数模型,具有强烈的空间相关性。闵行区地处城郊结合部,土壤Cu、Pb、Zn的半方差拟合模型均为线性模型,表现为纯块金形式,以随机变异为主,空间相关性弱。采用Kriging最优内插法进行无偏估值,绘制了表层土壤重金属含量的空间分布图,中心城区、城郊结合部、郊区土壤重金属的空间分布受城市化、工业化、城市交通等因素的影响,均表现出不同的空间分布规律。  相似文献   

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