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1.
海岸带处于陆地和海洋的接合部,人类开发活动密集,环境影响因素日趋复杂。选取烟台南部海岸带为研究对象,系统采集686个表层土壤样品对As,Cd,Cr,Cu,Hg,Ni,Pb,Zn共8个重金属元素含量进行测量,采用多元统计法及地统计法分析了8个重金属元素的来源及分布特征。最后对烟台南部海岸带地区进行了潜在生态风险评价。研究结果表明烟台南部海岸带地区整体污染程度较轻,所有重金属元素含量平均值均未超过国家二级标准。其中Cr,Ni,Cu元素主要来源于成土母质;As,Pb为混合源;Cd,Zn主要来自于工业三废、农业生产。研究区整体处于中低生态风险水平,Cd,Hg元素高生态风险点数量较多,需优先治理。  相似文献   

2.
There is an increasing concern for potentially hazardous metals pollution, which can threaten crops production and human health. In this study, the spatial distribution and environmental risks of eight heavy metals in surface soil samples collected from the paddy fields in Yongshuyu irrigation area, Northeast China were investigated. The mean concentrations of Pb, Cr, Cu, Ni, Zn, Cd, Hg and As were 34.6 ± 4.67, 82.8 ± 9.51, 17.3 ± 4.09, 21.2 ± 12.0, 88.6 ± 17.9, 0.18 ± 0.15, 0.22 ± 0.07 and 8.77 ± 2.47 mg/kg, respectively, which were slightly higher than their corresponding background values of Jilin Province, indicating enrichment of these metals in the paddy soils, especially for Ni, Cd and Hg. The spatial distribution of heavy metals was closely correlated with local anthropogenic activities, such as agricultural production, mining and transportation. The hot-spot areas of As and Cd were mainly concentrated in the up-midstream where were associated with agricultural activities. Cr and Cu showed similar spatial distributions with hot-spot areas distributed the whole irrigation area uniformly. Ni was mainly distributed in the downstream where Ni quarries concentrated, while the spatial distribution patterns of Hg was mainly located in the upstream and downstream where the soil was significantly influenced by irrigation and coal mining emission. The spatial distributions of Pb and Zn were mainly concentrated along the highway side. The pollution levels of Yongshuyu irrigation area were estimated through index of geo-accumulation(Igeo), Nemerow integrated pollution index(NIPI) and potential ecological risk index(PERI). The results showed that Cd and Hg were the main pollutants in the study area. Health risk assessment results indicated that children were in higher non-carcinogenic and carcinogenic risks than adults with the carcinogenic metal of As. Ingestion was the main exposure pathway to non-carcinogenic and carcinogenic risk for both adults and children. Principal component analysis(PCA) indicated that Cr and Cu were mainly from parent materials, while Cd and As were mainly affected by agricultural activities. Pb and Zn were controlled by traffic activities, and the accumulations of Ni and Hg were associated with mining activities. This study would be valuable for preventing heavy metals inputs and safety in rice production of the Songhua river basin.  相似文献   

3.
烟台近岸海域表层沉积物重金属污染特征   总被引:1,自引:0,他引:1       下载免费PDF全文
采取烟台近岸海域150个海底表层沉积物样品进行Hg,Cu,Pb,Zn,Cd,Cr,As,Ni元素分析。结果显示,烟台市近岸海域重金属主要富集在芝罘湾(Cd,Cu)、龙口(As,Cr,Cu)及海阳东部(Ni,Pb)一带,而莱州、招远及牟平近岸海域重金属含量较低。单因子、内梅罗和潜在生态危害指数评价结果显示,研究区88%海域的沉积物达到一类标准,轻污染区主要分布在芝罘岛北部及龙口市西部,龙口、招远及烟台市近岸沉积物潜在风险中等。  相似文献   

4.
根据2011年7月浙江舟山西蟹峙海洋倾倒区及邻近海域表层沉积物重金属的监测结果,采用单因子指数法和Hakanson生态危害指数法分析表层沉积物重金属的污染特征,并评价其潜在生态风险。结果表明:沉积物重金属元素Cu、Zn、Pb、Cd、Cr、Hg、As含量均符合国家海洋沉积物质量一类标准;重金属元素污染程度由高到低依次为Zn、Cr、Pb、Cu、As、Cd、Hg,其中Cu、Pb、Cd、Hg和As 5种重金属元素为低污染水平,Zn和Cr 2种重金属元素为中等污染程度水平;7种重金属元素单个和综合潜在生态危害程度均为低风险水平,由高到低依次为Cd、Hg、As、Pb、Cu、Cr、Zn。  相似文献   

5.
以山东省济南市章丘区北部表层土壤中As等8种重金属元素为研究对象,利用多元统计进行重金属来源分析,采用污染负荷指数法及潜在生态危害指数法进行污染评价,结果表明:研究区表层土壤重金属元素含量低于济南市土壤背景值,Cd和Hg元素含量为强度变异,在表层土壤产生一定的富集;不同土地利用类型下重金属元素含量具有差异性。土壤中Cr,Cu,Ni和Zn来源于土壤母质,Cd和Pb元素来源于人类活动,As元素来源复杂。土壤综合污染以轻度污染为主,重金属元素污染程度大小为AsNiPbZnCrCuCdHg。综合潜在生态风险以轻微和中度为主,潜在生态风险强弱程度为HgCdAsCuPbNiCrZn,建议防范Hg和Cd元素污染及生态风险。  相似文献   

6.
人类活动对水环境影响巨大,同时水环境影响着人类的生产生活。采用地质累积指数法及潜在生态危害指数法对武汉市东西湖区主要湖泊表层沉积物重金属情况展开评价发现东西湖主要湖泊表层沉积物平均污染程度处于相对较低水平。地累积指数法评价结果表明,东大湖和金湖中Cd元素处于中度污染水平累积,墨水湖和上金湖中Cd元素为偏中度污染累积水平,其他湖泊沉积物中重金属均处于轻度或无污染水平。潜在生态危害指数法评价结果表明金湖和东大湖沉积物中重金属的潜在风险处于重度生态风险水平,墨水湖、上金湖、下银湖处于中度风险水平,其余湖泊沉积物中重金属的潜在风险均处于低风险水平。主成分分析表明,Hg、Cr、Ni、Cu、Zn、Cd、Pb可能来自于工业和交通源的排放,而As可能与农药的使用有关。后期金湖、东大湖、墨水湖、上金湖和下银湖的内源污染治理过程中需考虑重金属的生态风险问题。   相似文献   

7.
研究石漠化峰丛洼地土壤重金属空间分异特征及其影响因素, 对推动区域土壤重金属污染防治、石漠化综合治理具有重要的指导意义和实践价值。以广西平果市典型石漠化峰丛洼地土壤为研究对象, 通过调查采样分析以及综合运用地统计学、地质累积指数、潜在生态危害指数和地理探测器等方法, 分析探讨土壤重金属的空间分异特征及其影响因素。结果表明, 研究区8种重金属元素的空间分布总体呈东北向西南降低的变化格局, 研究区东北部和东南部为重金属高值叠加区的集中分布区, Cr,Cd元素呈现中等的空间相关性, 其他6个重金属元素表现为强空间相关性;研究区受Cd,As,Cr,Cu,Zn等元素不同污染程度的影响, 且以Cd的影响尤为突出, 其地质累积指数和潜在生态危害指数分别高达1.34和107.73;pH、地层、Fe2O3、土地利用、P、CaO、Mn、到断层距离、石漠化程度是影响研究区土壤重金属空间分异的主要因子, 而且不同因子组对土壤重金属空间分异的交互作用以双因子增强型和非线性增强为主。因此认为不同因子对石漠化峰丛洼地土壤不同重金属元素空间分异特征的影响程度存在差异, Cd是石漠化峰丛洼地土壤污染程度和潜在生态危害程度最严重的重金属元素, 地层、Mn、CaO、岩性、到断层距离、P是影响Cd空间分异的关键因子。   相似文献   

8.
To determine the pollution levels and potential toxic risks of arsenic(As) and heavy metals(Cr, Ni, Cu, Zn, Pb and Cd) in water and suspended particulate matter(SPM) in tail reaches(including freshwater reach and low-salinity reach) of the Yellow River as the Flow-Sediment Regulation Project(FSRP) has been carried out for approximately 15 yr, the surface water and SPM were sampled at pre-flood(April) and post-flood seasons(October). Results showed that similar changes of As and metal levels in water and SPM were observed along the tail reaches at pre-flood or post-flood season. Compared to pre-flood season, the levels of As, Cu, Cr and Ni in freshwater reach and the concentrations of Cr and Ni in low-salinity reach rose greatly at post-flood season. The levels of As and metals in SPM of freshwater reach or low-salinity reach at pre-flood season were significantly higher than those at post-flood season(P < 0.01).The pollutions of As and metals in surface water of tail reaches at pre-flood or post-flood season were not serious. The SPM in freshwater reach at pre-flood season were polluted by Cd, As, Cr, Cu and Ni while those in low-salinity reach were polluted by Cd and Cr. The SPM in freshwater reach at post-flood season were polluted by Cd and Pb while those in low-salinity reach were polluted by Cd and Cr.Cd was identified as heavy metal of primary concern at both pre-flood and post-flood seasons. Combined with the existed data reported in present research, this study found that the toxic risk of As and metals in SPM of tail reaches at pre-flood season was higher than that at post-flood season, implying that the implementation of FSRP during flooding season, to a great extent, reduced the toxic risk of these elements. With the long-term implementation of FSRP, the pollution levels of As and metals(particularly for Cd) in SPM of tail reaches might be elevated and the potential toxic risk primarily produced by Cr, Ni and As might be increased if effective measures were not taken in future.  相似文献   

9.
Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment(0 cm, NBT), current burial treatment(10 cm, CBT) and strong burial treatment(20 cm, SBT), were designed in intertidal zone of the Yellow River Estuary to determine the potential influences of episodic deposition on nutrient(C, N) and heavy metal(Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT(0.002 403/d) SBT(0.002 195/d) NBT(0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments(P 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh.  相似文献   

10.
Metal pollution has become an major issue governing the wetland ecosystem health.The southern coastal wetland of the Qiangtang Estuary are facing unusual perturbation due to rapid development along the embayment in recent decades.This study evaluated the bioavailability of metals(Cu,Pb,Cd,Cr and Zn)in the sediment of the southern coastal wetland of the Qiangtang Es-tuary using diffusive gradients in thin films(DGT)techniques and compared with several methods based on total metal content.The results showed that the contents of Cr,Pb,Cd and Cu in sediment,as detected using DGT,were considerably correlated with the exchangeable fraction and the content in Phragmites australis roots,while a weak correlation was observed for Zn.Therefore,DGT analysis could be used to evaluate the bioavailability and potential risk of Cr,Cd,Pb and Cu for P.australis.Quantitative indices,such as DGT concentration,bioaccumulation in P.australis,geoaccumulation index(Igeo)and potential ecological risk index(RI),revealed that Cd was a major potential ecological risk factor along the southern coast wetland of the Qiantang Estuary,especially in the upstream region,which is potentially more vulnerable to the anthropogenic pollution.  相似文献   

11.
资江是洞庭湖的第二大支流,其中上游锑(Sb)矿采矿冶炼工业发达,给资江下游及洞庭湖区带来了严重的重金属污染风险。以资江河口区为研究区,采集了132个农田土壤样品及7个资江水样,综合采用多种污染评价方法、空间分析、多元统计分析方法对研究区重金属进行了污染评价及来源分析。结果表明,研究区农田土壤重金属平均质量分数表现为Zn>Cr>Ni>Pb>Cu>As>Sb>Cd,旱田土壤重金属平均质量分数除Pb外均高于水田。Sb、As、Cd为主要污染元素,Sb达到了中等污染和中等生态风险的程度,总体处于轻微-中等生态风险程度。资江水体Sb质量浓度较高,平均为10.51 μg/L。Sb主要来源于中上游的锑矿工业,受高锑质量浓度地表水灌溉、垃圾填埋场以及燃煤等人为活动的控制;Cd主要来源于农药化肥、生活垃圾和城镇废水等人为活动;Cr主要来源于成土母质,而Cu、Zn、As、Ni、Pb受成土母质和人为活动的双重控制。   相似文献   

12.
Heavy metal pollutants are a worldwide concern due to slow decomposition, biocondensation, and negative effects on human health. We investigated seasonal and spatial variations of the five heavy metals and evaluated their health risk in the Liaohe River, Northeast China. A total of 324 surface water samples collected from 2009 to 2010 were analyzed. Levels (high to low) of heavy metals in the Liaohe River were: zinc (Zn) > chromium (Cr) > copper (Cu) > cadmium (Cd) > mercury (Hg). Spatial and seasonal changes impacting concentrations of Cu and Zn were significant, but not significant for Cr, Cd and Hg. The highest concentrations of heavy metals were: Hg at Liuheqiao, Cu at Fudedian, Zn at Tongjiangkou, Cr at Mahushan, and Cd at Shenglitang. The highest concentrations of Hg and Cr were found in the wet period, Cu and Cd in the level period, and Zn in the dry period. The surface water of a tributary was an important accumulation site for heavy metals. Health risks from carcinogens and non-carcinogens increased from upstream to downstream in the mainstream of the Liaohe River. The total health risk for one person in the Liaohe River exceeded acceptable levels. The total health risk was the greatest during the wet period and least in the dry period. Among the five heavy metals in the Liaohe River, Cr posed the greatest single health risk.  相似文献   

13.
The form in which a metal exists strongly influences its mobility and thus, the effects on the environment. Operational methods of speciation analysis, such as the use of sequential extraction procedures, are commonly applied. The Dongting Lake, the second largest fresh-water lake in China, contains three China wetlands of international importance, the East Dongting Lake, South Dongting Lake, and West Dongting Lake. In this work, an optimized BCR sequential extraction procedure was used to assess the environmental risk of Cd, Cr, Cu, Ni, Pb and Zn in contaminated sediment of the Dongting Lake. The procedure was evaluated by using a certified reference material, BCR701. The results of the partitioning study indicated that in the lake sediments, more easily mobilized forms (acid exchangeable) were predominant for Cd, particularly in the samples from the East Dongting Lake. In contrast, the largest amount of Pb was associated with the iron and manganese oxide fractions and Cu, Zn, Cr, and Ni analyzed were mainly distributed in residual phase at an average percentage greater than 60% of the total metals. The potential risk to the lake's water contamination was highest in the East Dongting Lake based on the calculated contamination factors. On the other hand, the total metal content was determined as well by inductively coupled plasma and mass spectrometry (ICP-MS) and assessed by using geo-accumulation index. The assessment results using geo-accumulation index were compared with the information on metal speciation. Both were correspondent with each other.  相似文献   

14.
通过对滨州近海海域海底沉积物测试数据及海岸带陆域土壤地球化学分析,对滨州海岸带陆域土壤和海底沉积物中7种重金属(Hg,Cd,Pb,Cu,Zn,Cr,Ni)的空间分布特征进行了研究,并绘制了各指标含量陆海联合分区图。分析结果表明,滨州市海岸带重金属元素含量基本上均低于国标规定的海洋一类沉积物的最高标准,仅有个别元素含量超过一级标准值,表明局部存在一定的重金属污染。从滨州海岸带重金属含量空间分布上来看,除Hg元素外,其余重金属元素含量呈现一定的规律,基本上陆域含量高于海域含量,且大部分元素都呈现出陆域城镇值高,郊区值低的态势。区内化工企业较发达,Ni,Cr属于中度变异区,Cd,Hg,Pb属于高度变异,受人为影响因素较大,考虑区内土壤及海底沉积物重金属富集主要来源于工业"三废"。  相似文献   

15.
农用地土壤中7种重金属可提取态的测定   总被引:1,自引:0,他引:1       下载免费PDF全文
该文以氯化钙溶液进行提取,采用电感耦合等离子体质谱法和原子荧光光谱法,测定农用地土壤中Cd,As,Pb,Cr,Cu,Zn,Ni等7种重金属可提取态,检出限在0.003~0.06 mg/kg之间。该方法用于4个可提取态质控样品的测定,测定值与推荐值基本相符,测定的相对标准偏差(n=8)在3.3%~9.1%之间。基于800余件农用地土壤样品的测定数据,对7种重金属可提取态与土壤pH值及重金属总量之间的关系进行了初步考察。结果表明,7个重金属可提取态和总量关系无明显相关性,仅在土壤酸性条件下可提取态Cd与总量Cd呈正相关性。7种重金属提取率大小顺序为Cd>Zn>Ni>Cu,As>Pb>Cr,其中Cd,Zn,Ni,Cu,Pb的提取率随土壤pH值的增大而迅速下降,而As,Cr在土壤碱性条件下的提取率略高于中酸性条件下的提取率。  相似文献   

16.
We analyzed heavy metal concentrations in a number of surface sediments and cores from the Qiongzhou Strait and surrounding marine areas.The areas of high concentrations are primarily outside the eastern mouth of the Qiongzhou Strait and on the west side of the Leizhou Peninsula,whereas the areas of low concentrations are located primarily in the eastern Qiongzhou Strait.The maximum Cd,Pb and Zn concentrations in the samples collected in our study do not exceed the official standards for marine sediments,whereas the concentrations of Cr and Cu slightly exceed the standards.Correlations exist between the concentrations of Cu,Pb,Zn,Cr and Cd,and the concentrations of these metals are positively correlated with the mean particle size(φ value),indicating that the finer sediments have adsorbed greater amounts of heavy metal elements than the coarser sediments.An evaluation of the potential environmental risks demonstrates that certain indices of heavy metal pollution and environmental risks are relatively low and may be assigned low risk levels,thereby indicating that,in terms of heavy metals,the marine sedimentary environment in this region is only mildly impacted.Our analysis of the contaminant origins shows that the heavy metals in this region primarily originate in the Pearl River Estuary and that a small amount of them is derived from local runoff.The elevated heavy metal concentrations from the upper sections of the cores started 130 years ago,which indicats that heavy metals in the surface sediments are primarily due to human activities associated with industrialization.  相似文献   

17.
The Nanfei River(Anhui Province,China) is a severely polluted urban river that flows into Chaohu Lake.In the present study,sediments were collected from the river and analyzed for their heavy metal contents.Multivariate statistics and the fuzzy comprehensive assessment method were used to determine the sources of pollution,the current pollution status,and spatial and temporal variations in heavy metal pollution in sediments.The concentrations of arsenic(As),cadmium(Cd),chromium(Cr),copper(Cu),mercury(Hg),nickel(Ni),lead(Pb),and zinc(Zn) in sediments ranged from 5.67–113,0.08–40.2,41.6–524,15.5–460,0.03–4.84,13.5–180,18.8–250,and 47.9–1 996 mg/kg,and the average concentrations of each metal were 1.7,38.7,1.8,5.5,18.8,1.3,2.5,and 11.1 times greater than the background values,respectively.Multivariate statistical analysis demonstrated that Hg,Cu,Cr,Cd,and Ni may have originated from industrial activities,whereas As and Pb came from agricultural activities.The fuzzy comprehensive assessment method,based on the fuzzy mathematics theory,was used to obtain a detailed assessment of the sediment quality in the Nanfei River watershed.The results indicated that the pollution was moderate in the downstream tributaries of the Nianbu and Dianbu Rivers,but was severe in the main channel of the Nanfei River and in the upstream tributaries of the Sili and Banqiao Rivers.Therefore,sediments in the Nanfei River watershed are heavily polluted and urgent measures should be taken to remedy the status.  相似文献   

18.
Aerosol samples were collected at two coastal suburban stations, Qingdao (China) in 1995-1996 and Liverpool (U.K.) in 1995, respectively. The samples were analyzed to determine the concentrations of trace metals (Cr, Zn, Cu, Co, Ni, Pb, V, and Cd) as well as A1, Fe and Mn. Data were examined to understand the difference of trace metals in aerosols between coastal zones downwind the developing area (near the Yellow Sea) and developed region (near the Irish Sea). The results show that most elements at Qingdao have levels 4-5 times higher than those at Liverpool, particularly for the crust-dominated elements (e.g. Al, Fe and Mn). Moreover, the aerosol composition at Qingdao is higher in spring than in summer, underlying the influence of westerlies and local emissions in combination, whereas seasonal change of aerosol composition is not significant at Liverpool. The enrichment factors for the crustal source elements (EFcrust) at Liverpool are much higher than those at Qingdao. The contributions from the pollutant source (Rp) for some trace metals like Cu, Pb, Zn and Cd are 〉90% at Qingdao and Liverpool, suggesting overwhelming anthropogenic contributions to these metals. The contributions from crustal source (Re) for trace metals tend to increase with higher aerosol levels and Al concentration at Qingdao, indicating a good correlation between the crust-dominated component and the air mass. At Liverpool, the Rc values for trace metals are positively correlated with Al concentrations instead of with aerosol mass, suggesting that Al in aerosols represents the crustal component even though the aerosols come from different sources.  相似文献   

19.
1IN T R O D U C T IO N With therapiddevelopment of urbanizatio,nurban land was exploitedand utilizetdoform differendtomains be- ing subjectto many potentialpollutionsourcessuch as vehicleemission, industrialactivitieasnd household garbage.Particularl, yur…  相似文献   

20.
At present, the methods widely applied to assess ecological risk of heavy metals are essentially single-point estimates in which exposure and toxicity data cannot be fully used and probabilities of adverse biological eff ects cannot be achieved. In this study, based on investigation of concentrations of six heavy metals (As, Hg, Pb, Cd, Cu, and Zn) in the surface seawater and sediment near the outlet of a zinc factory, located in Huludao City, Liaoning Province, China, a tiered approach consisting of several probabilistic options was used to refine ecological risk assessment for the individuals. A mixture of various heavy metals was detected in the surface seawater, and potential ecological risk index (PERI) was adopted to assess the potential ecological risk of heavy metals in the surface sediment. The results from all levels of aquatic ecological risk assessment in the tiered framework, ranging from comparison of single eff ects and exposure values to the use of distribution-based Hazard Quotient obtained through Monte Carlo simulation, are consistent with each other. Briefly, aquatic Zn and Cu posed a clear ecological risk, while Cd, Pb, Hg, and As in the water column posed potential risk. As expected, combined ecological risk of heavy metal mixture in the surface seawater was proved significantly higher than the risk caused by any individual heavy metal, calculated using the concept of total equivalent concentration. According to PERI, the severity of pollution by the six heavy metals in the surface sediment decreased in the following sequence: Cd>Hg>As>Pb>Cu>Zn, and the total heavy metals in the sediment posed a very high risk to the marine environment. This study provides a useful mathematical framework for ecological risk assessment of heavy metals.  相似文献   

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