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1.
基于秦皇岛滨海湿地人工种植耐高盐碱蓬修复工程试验,通过分析湿地土壤沉积物及耐高盐碱蓬中不同金属元素的含量与变化,研究了耐高盐碱蓬对金属元素的富集特征。结果显示:湿地沉积物中Fe、Mn、Cr、Pb和Zn的浓度较高,分别为8 210. 94、110. 04、8. 78、8. 25、10. 95 mg/kg,Cd的浓度最低,平均值为0. 022 mg/kg,湿地试验区土壤中同一金属元素变异程度较小,分布较均匀。碱蓬体内重金属含量根据采集地点的不同有差异,但与各站位中土壤的重金属分布特征存在正相关性;其中碱蓬内Fe、Mn、Zn、Cu的平均含量相对较高,且Fe、Mn、Ni、Cu、As、Cd、Pb元素在碱蓬根中的平均含量高于茎叶,而Cr在茎中的平均含量最高,Zn和Mo在叶中的含量最高。碱蓬的根、茎、叶对Cd的富集效果最好,其次为Mo、Cu,对Fe、Mn、Zn、As和Pb的富集效果相对较差,说明碱蓬对沉积物中不同金属元素的富集移出率存在差异。金属元素在碱蓬中的转移系数研究表明,Mo、Zn、Cd和Mn等元素可由根部转移到叶中,而Fe、Ni、Pb、As和Cu等金属元素固定在根部,该研究可为利用碱蓬修复湿地重金属污染提供理论基础。  相似文献   

2.
以贵阳某污灌区菜地土壤为研究对象,分别采用微波消解-电感耦合等离子体质谱(ICP-MS)法和水合热重铬酸钾氧化分光光度法分析不同粒径土壤团聚体中重金属和有机碳的含量特征,并对有机碳和重金属的相关性进行分析。结果表明,以2mm粒径团聚体的含量为最高,约占75%。Cu、Zn、Cd和Pb在0.25~0.5mm粒径团聚体中含量最高,Cr在5~8mm粒径团聚体中含量最高,As在不同粒径团聚体中的含量变化不大,重金属含量随土层深度增大而减小。土壤重金属富集因子表现为CuPbCdZnCrAs,Cu、Zn、Cd和Pb在0.25~0.5mm粒径团聚体中分布因子最高,而在5~8mm粒径团聚体中重金属的质量负载因子最大。土壤有机碳含量随团聚体粒径的增大表现为先增大后减小,不同粒径团聚体中Cu、Cd、Pb和As含量与有机碳含量均呈显著正相关(p0.05)。污灌区菜地土壤Cr、As在5~8mm粒径团聚体中富集现象显著,Cu、Zn、Cd、Pb在0.25~0.5mm粒径团聚体中均表现出显著的富集特征。6种重金属在5~8mm粒径团聚体中的质量负载因子均为最高,表明6种重金属在5~8mm粒径团聚体中的贡献最大。  相似文献   

3.
This paper reviews quite a few heavy metal contamination related studies in several cities from China over the past 10 years. The concentrations, sources, contamination levels, sample collection and analytical tools of heavy metals in urban soils, urban road dusts and agricultural soils were widely compared and discussed in this study. The results indicate that nearly all the concentrations of Cr, Ni, Cu, Pb, Zn, As, Hg and Cd are higher than their background values of soil in China. Among the cities, the contamination levels of the heavy metals vary in a large range. The geoaccumulation index shows that the contamination of Cr, Ni, Cu, Pb, Zn and Cd is widespread in urban soils and urban road dusts of the cities. Generally, the contamination levels of Cu, Pb, Zn and Cd are higher than that of Ni and Cr. Agricultural soils are also significantly influenced by Cd, Hg and Pb derived from anthropogenic activities. The integrated pollution index (IPI) indicates that the urban soils and urban road dusts of the developed cities and the industrial cities have higher contamination levels of the heavy metals. The comparison of the IPIs of heavy metals in urban soils and urban road dusts of Shanghai, Hangzhou, Guangzhou and Hongkong reveals that the contamination levels of the metals in urban road dusts are higher than that in urban soils in the cities. Moreover, the main sources of the metals in urban soils, urban road dusts and agricultural soils are also different.  相似文献   

4.
In developing countries, the dietary intake of essential elements is largely dependent on the consumption of edible fruits and leafy vegetables. The distribution of elements in the indigenous edible plant, Obetia tenax (mountain nettle), was investigated as a function of soil quality from eight sites in KwaZulu-Natal, South Africa. The results show concentrations of elements in the leaves to be in decreasing order of Ca?>?Mg?>?Fe?>?Mn?>?Zn?>?Cr?>?Cu?>?Ni?>?Pb?>?Co?>?As?>?Cd?>?Se, and in the stems and roots to be in decreasing order of Ca?>?Mg?>?Fe?>?Mn?>?Zn?>?Cu?>?Ni?>?As?>?Pb?>?Co?>?Cd?>?Cr?>?Se. The quality and pollution status of soil was evaluated by geoaccumulation indices and enrichment factors, which indicated moderate cadmium contamination at the Msinga location that was confirmed by the pollution index and ecological risk levels of single-factor pollution. An assessment of overall contamination of soil using Nemerow pollution index showed moderate pollution by cadmium, while the potential toxicity index indicated low-grade risk for all elements at all sites. Principal component and cluster analysis revealed two groups of elements with similarities, As, Cd, Co, Cr, Cu, Mn, Ni, and Fe, suggesting a lithogenic source and an anthropogenic source for Pb and Zn. Correlation analysis showed significantly positive correlations between As, Co, Cr, Cu, Fe, and Ni/Cd in the soil, confirming the elements’ common origin.  相似文献   

5.
为比较6种重金属元素在甜瓜植株各器官中富集及转运能力的差异,于果实成熟期采集土壤、根、茎、叶、果实并测定其中的Cr、Cu、As、Ni、Pb和Cd 6种重金属元素,在此基础上,通过富集系数、转运系数,评估了植株不同器官中重金属元素富集能力的差异,比较了各迁移阶段6种重金属元素转运能力的差异。结果显示,各器官中,根富集重金属元素的能力最强,较其他受试重金属元素,Cd和Cu更易在甜瓜植株中富集;迁移各阶段中,Cr、Ni、As、Pb 4种重金属元素由茎转运至果实和叶片的能力相对较强,Cd由根转运至茎的转运能力更强;重金属元素Cu由茎转运至叶片的能力相对较弱。不同重金属元素在甜瓜植株各器官中的富集、转运能力有所差异,宜根据目标调控重金属元素种类,开展对应主要转运阶段阻滞技术的研究与探讨。  相似文献   

6.
本文旨在分析湖北典型地区茶叶以及土壤中各种元素的含量,采用原子荧光法(AFS)和电感耦合等离子体质谱法(ICP-MS)等方法对135对茶叶及土壤样品进行测定,并探讨各种元素之间的相互关系和影响。研究结果表明,土壤中元素的分布对茶叶中元素含量分布有一定意义,典型区土壤养分有效磷和碱解氮较丰富,有机质和速效钾较缺乏。典型区茶叶作物表层土壤 Cd、Pb、Cu、Cr、As 均存在不同程度的超标。土壤 Cd 和 Hg 的污染指数高,潜在生态风险强。典型区茶叶可食部分重金属含量均值依次为 Cu>Pb>Cd>Hg>As>Cr,重金属元素在茶叶中含量均为中等变异性。 茶叶对 Cu、Pb 的富集系数明显高于 Hg、As、Cd、Cr,不同茶叶对同一元素的富集能力存在差异。土壤重金属含量与土壤 pH 值、CEC、有效磷、总氮等理化指标关系密切。茶叶重金属含量与土壤重金属含量水平相关性较弱,但与茶叶对重金属的富集能力均呈显著正相关关系。  相似文献   

7.
湛江湾红树林湿地土壤重金属含量分析及污染评价   总被引:1,自引:0,他引:1  
采用电感耦合等离子体发射光谱仪(ICP-AES)和电感耦合等离子体质谱仪(ICP-MS)对湛江湾红树林湿地土壤中8种重金属(As、Cu、Cd、Cr、Hg、Ni、Pb、Zn)含量进行测定,采用单因子污染指数法、内梅罗综合污染指数法和地累积指数法进行污染评价,并结合相关性分析和因子分析方法探讨重金属来源。结果表明:除Ni外,其余7种重金属元素含量平均值均未超过国家土壤环境质量标准(GB15618-2018);但Ni、Zn、Cu、Hg、As和Cd元素均超过广东砖红壤环境背景值,其中As、Ni、Hg和Zn元素超标情况严重。8种重金属元素内梅罗综合污染指数评价结果为0.373~22.576,平均值为3.378,整体处于重度污染;单因子污染指数依次为Ni>Hg>Zn>Cd>As>Cu>Pb>Cr。单个重金属元素地累积指数评价结果与内梅罗综合污染评价相一致,均显示红树林土壤中Hg、Zn和Ni元素污染严重,是影响研究区土壤环境质量的重要因素。从站位看,位于湾内北部的北涯村、观海长廊以及西部的世乔村站位污染较严重,高污染站位约占总站位数的33%,主要为Cd、Hg和Zn。统计分析结果显示,除Ni外,湛江湾红树林土壤中7种重金属元素之间显著相关;结合实地调查结果推测重金属污染主要来自工业污染、船舶排污、养殖排污、生活排污及农业面源污染等人为活动的输入,其次为自然因子的输入。  相似文献   

8.
Many mine soils are chemically, physically, and biologically unstable and deficient. They are sometimes amended with sewage sludge and ashes but often contain heavy metals that increase the already high mine soils' heavy metal contents. Cd, Cr, Cu, Ni, Pb, and Zn in mutual competition were added to five mine soils (Galicia, Spain). Soil capacities for heavy metal sorption and retention were determined by means of distribution coefficients and selectivity sequences among metals. Influence of soil characteristics on sorption and retention was also examined. Retention selectivity sequences indicate that, in most of the soils, Pb is the preferred retained metal, followed by Cr. The last metals in these sequences are Ni, Cd, and Zn. Soil organic matter content plays a fundamental role in control of Pb sorption. Gibbsite, goethite, and mica influence Cr retention. Soil organic matter, oxides, and chlorite contents are correlated with K(d sigma sp medium). Heavy metals are weakly adsorbed by soils and then desorbed in high amounts. To recover these soils it is necessary to avoid the use of residues or ashes that contain heavy metals due to their low heavy metal retention capacity.  相似文献   

9.
Inductively coupled plasma-mass spectrometry (ICP-MS) and neutron activation analysis (NAA) were employed in the determination of heavy metal concentrations in water, plant and sediment samples to assess the extent of heavy metal pollution in a river system which is located within an industrial zone. Elemental concentrations of As, Pb, Hg, Cr, Cu, Cd, Ni and Zn were measured in the samples. Statistical analysis was performed on the data obtained to look for trends in the pollution pattern of these elements on the river system. The trend in concentrations of heavy metals pollution in water samples is in the order of Zn > Cu > Ni > Cr > As > Pb > Hg > Cd, whereas in plants the order is Zn > Cr > Cu > Pb > Ni > As > Hg > Cd and in sediments Zn > Cu > Pb > Ni > As > Hg.  相似文献   

10.
杭州西郊茶园土壤重金属的积累特点与来源分析   总被引:6,自引:0,他引:6  
选择了杭州市西部近郊、远郊和农村等3个受人为不同程度影响的区块,分析了同为第四纪红土母质发育的茶园与附近林地土壤剖面中重金属垂直分布的特点,探讨了茶园土壤重金属的来源。结果表明,相同区块的茶园与附近林地土壤重金属Pb、Cd和Hg剖面分布相似,均随剖面深度下降,表土Pb、Cd和Hg含量随离城市距离增加而下降,说明研究区茶园土壤中重金属Pb、Cd和Hg的积累主要与大气沉降有关;茶园与附近林地土壤重金属Cu和Zn也随剖面深度而下降,但同一区块中茶园表土重金属Cu和Zn含量明显高于附近林地土壤,说明施肥等农业措施对茶园土壤Cu和Zn的积累有较大的影响;茶园土壤中Cu和Zn的积累与地理位置关系不大。茶园土壤中Cr和Co的积累不明显,并有淋失的趋势。  相似文献   

11.
为研究黔产市售绿茶中重金属的含量分布特征及健康风险,以五个生产加工地的黔产市售绿茶为研究对象,分析其9种重金属(Pb、Cr、Cd、Hg、Cu、Zn、Mn、Ni和As)含量,利用美国环境保护署(USEPA)推荐的健康风险评价模型进行人体重金属的健康风险评价。结果表明,五种茶叶中Cr、Cd、Pb、Hg、Cu和As含量均低于国家限量标准。黔产市售绿茶的重金属浸出率大小次序为Zn>Mn>Hg>As>Cd>Pb>Cr>Cu>Ni。健康风险评价结果表明,五个产地的绿茶中重金属通过饮茶途径所产生的健康危害个人年风险大小次序为Cd>As>Mn>Ni>Cr>Hg>Pb>Zn>Cu,茶叶中重金属通过饮茶途径所产生的个人健康危害年风险总和为4.33×10-6~5.73×10-6 a-1,均低于USEPA和ICRP推荐的最大可接受风险水平,表明重金属引起的健康危害极小,其对暴露人群造成的健康危害可忽略不计,绿茶中重金属均处于安全范围内。  相似文献   

12.
The research reveals results of metal pollution on urban topsoil in relation to the metal content in leaves of two plant species and atmospheric particles. The content of pollutants (Ba, Cd, Cu, Fe, Mn, Ni, Pb, V and Ti) was determined by ICP-OES. Twenty-two samples of soil were collected over a six-month period from two different urban sites and one from a rural zone. Regarding the pollution level, the studied soils were found to be low. Results for enrichment (EF) and concentration (CF) factors showed that soils were enriched in Pb, Ba, Cu and Ni. However, both species of plants showed a common behavior for all elements acting as excluders. ANOVA and different multivariate statistical analyses confirmed that the main pollution source of soil was traffic and fertilizers. Cd, Fe, Mn, Ti and V elements were attributed to natural sources. Also, it was suggested that N. oleander leaf is useful as a bio-monitors of soil pollution by Cu. Similarly, a direct relationship was found between the content of Cu in soils with the Cu level in PM10 atmospheric particles. The origin was attributed to dry and wet atmospheric deposition processes.  相似文献   

13.
成都市农业土壤重金属污染特征初步研究   总被引:16,自引:0,他引:16  
对成都市农业土壤中七种重金属元素Pb、Hg、Cr、As、Cu、Zn和Cd进行了测定和研究,并进行了潜在生态风险评价。结果表明,成都市农业土壤重金属元素含量分别为:Pb 77.27mg/kg,Hg 0.31 mg/kg,Cr 59.50 mg/kg,As 11.27 mg/kg,Cu 42.52 mg/kg,Zn 227.00 mg/kg,Cd0.36 mg/kg;重金属潜在的生态危害因子表明,Hg和Cd达到中等生态危害程度,Pb、As、Cu、Zn、Cr达到轻微生态危害;多种重金属的生态系统的潜在生态风险指数(RI)表明,成都市农业土壤生态危害级别为中等生态危害。  相似文献   

14.
佛山市蔬菜中若干重金属元素含量调查与分析   总被引:7,自引:0,他引:7  
对广东佛山市蔬菜中重金属含量进行了调查与分析。结果表明,蔬菜中重金属元素含量取决于蔬菜种类和土壤环境,佛山市蔬菜中重金属元素含量基本上是正常的,仅个别样点土壤受污染,蔬菜重金属元素含量异常。蔬菜中重金属元素含量由高到低顺序大体上是:叶菜类,瓜果类蔬菜,根菜类蔬菜。蔬菜必需元素锌、铜含量比汞、镉、铅、铬、镍等非必需元素含量高。  相似文献   

15.
用植物叶片中重金属元素含量指示大气污染的研究   总被引:29,自引:0,他引:29  
通过对潮州市区交通繁忙路段和对照区 (红山森林公园 )不同植物叶片重金属元素 (Pb、Cd、Cu、Zn)的含量研究 ,探讨了重金属含量与城市大气污染之间的关系。结果表明 ,植物叶片中的重金属元素富积量和大气中污染指数正相关。植物叶片的重金属元素富积量可较好和客观地指示市区大气的重金属污染状况。该研究为城市规划和环境保护提供了科学依据  相似文献   

16.
有色金属矿产资源采选冶活动造成的土壤重金属污染已成为严重的环境问题。采用电感耦合等离子体质谱法和光谱法测定某冶炼厂周边不同区域内土壤中重金属Cu、Pb、Zn、As、Ni、Cr、Cd、Hg元素含量,采用Kriging空间插值方法对重金属空间分布特征进行分析,采用内梅罗指数法对其污染状况进行评价,采用多元统计分析对重金属元素的污染源进行分析。结果表明,研究区土壤采样点80%处于污染状态,且以重度污染为主,污染比较严重的区域受风向影响在冶炼厂的西部和南部方向,污染严重的重金属元素为Cu、Pb、Cd、Zn和As,土壤中各重金属元素的污染源除来自于冶炼厂外,Zn-Cd-PbCu-As、Ni-Cr、Hg分别还受到机动车辆排放、自然因素、燃煤及农药使用的影响。  相似文献   

17.
《Analytical letters》2012,45(13):2122-2131
China has one of the fastest-growing economies in the world, but this economic development has important implications for environmental changes in this country. Our research was to quantify the presence of heavy metals in soil and water environments in the Tianshan Mountains region of China, associated with the economic development of this region. We used anomaly analysis, correlation analysis, and principal component analysis to assess the occurrence characteristics of heavy metals in this area. Results showed that Co, Cr, As, and Ni are more prevalent in water environments than in soil environments; in contrast, Cd, Zn, Pb, Hg, and Mn are more prevalent in soil samples than in water samples. This analysis grouped 10 heavy metals in soil and water environments into three principal components. In soil environments, the prevalence order was Co, Ni, Cr, As > Mn, Zn, Pb > Hg, Cd, Cu. In water environments, the order was Cu, Co, Ni, Cr, As > Hg, Mn, Zn > Cd, Pb. It is possible to distinguish between the natural and the anthropogenic sources of heavy metals in the Tianshan Mountains. With the current rapid economic development in the Tianshan Mountains, anthropogenic sources are playing principal roles in serious heavy metal accumulations in this region. This problem warrants immediate and widespread attention to prevent further deterioration of the soil and water environments.  相似文献   

18.
Abstract

Natural organic chelating agents take part in the mobilization and translocation of heavy metals in unpolluted and polluted soils. They also have to be considered as possible extracting agents for the decontamination of heavy metal polluted soils. For an assessment of the desorption capability of glycinc, heavy metals (Cd, Cu, Ni, Pb, Zn) were adsorbed onto typical soil components (bentonite and peat). The metal loaded sorbents were resuspended in aqueous solutions of glycine at pH 7.0 and 4.5 and the quantities of the desorbed metals were analysed in the liquid phase. Furthermore, the dependency of the desorption rate on the duration of experiments and the metal content were investigated. The remobilization of heavy metals from bentonite by glycine at pH 7.0 decreases following the order Cu > Ni > Zn > Cd > Pb and ranges from 95% to 9.5%. The desorption rate was significantly lower at pH 4.5 and in suspensions of peat.  相似文献   

19.
The study is conducted to investigate the spatial distribution, sources and ecological risk of seven heavy metals in surface sediments of Nansi Lake, Eastern China. A total of 29 samples were collected in surface sediments of Nansi Lake, and were analyzed for three nutrients (TN, TOC and TP), two major metals (Al and Fe), as well as seven trace metals (As, Cd, Cr, Cu, Hg, Pb and Zn). The mean concentrations of As, Cd, Cr, Cu, Hg, Pb, Zn, Fe and Al were 14.41, 0.22, 71.10, 30.1, 0.048, 29.14, 90.2, 30,816 and 70,653 mg kg?1, respectively, and the mean contents of these metals were higher than the background values with the exception of Cu and Fe. The spatial distribution indicated that the contents of all seven heavy metals were characterized by relatively higher contents in the upper lake than the lower lake. The hotspots with high values of As, Cd and Hg were associated with the river mouths, and the hotspots of Pb were mainly located around the dam in the central part, while no significant associations were displayed between spatial distribution of Cr, Cu, Zn and the river mouths. The mean enrichment factor (EF) values of As, Cd, Hg and Pb were 2.03, 2.93, 3.21 and 2.18, respectively, showing their moderate enrichment, while Cr, Cu and Zn with mean EF values of 1.19, 0.89 and 1.01 were deficiency to minimal enrichment. Multivariate and geostatistical analyses suggested that PC1 controlled by Cr, Cu and Zn was a lithogenic component, and come from parent rocks leaching. PC2 including Cd and partially Hg represented the factor from industrial wastewater discharge. PC3 showed elevated loadings of As and partially Cd, and could be attributed to the agricultural practices. While PC4 including Pb and partially Hg, was dominated by coal combustion. The results of potential ecological risk suggested that sediment environment of Nansi Lake suffered from high ecological risk.  相似文献   

20.
This study reports the spatial distribution pattern and degree of heavy metal pollution (Cd, Cr, Cu, Ni, Pb, Mn, Be, Co, Zn and U) in 169 urban road dust samples from urban area of Urumqi city. The spatial distribution pattern shows that Cu, Pb, Cr and Zn have similar patterns of spatial distribution. Their hot-spot areas were mainly associated with main roads where high traffic density was identified. Ni and Mn show similar spatial distributions coinciding with the industrial areas, while the spatial distribution patterns of Co and U show hot-spot areas were mainly located in the sides of the urban area where the road dust was significantly influenced by natural soils. The spatial distributions of Be and Cd were very different from other metals. The geo-accumulation index suggests that road dust in Urumqi city was uncontaminated to moderately contaminated with Cd, Cu, Ni, Pb, Mn, Be, Zn and U. The integrated pollution index shows IPIs of all road dust samples were higher than 1, suggesting that the road dust quality of Urumqi city has clearly been polluted by anthropogenic emission of heavy metals. Moreover, the spatial distribution pattern of IPIs also shows several distribution trends in the studied region.  相似文献   

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