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1.
This article presents the results of the analysis of the metals lead, cadmium, copper, zinc and aluminum, conducted on a total of 112 soil samples arising from 57 sampling points, distributedthroughout the Cartagena area in southeastern Spain. Both, totalmetal content and soluble fraction (1 M nitric acid medium, exchangeable fraction) were analyzed. Soil samples were taken on the surface of the terrain and at a depth of 35 cm from eachsampling point. For the purposes of this study, sampling points were classified in three groups based on the results of previous research on air pollution in the region: clean areas,contaminated areas and vacant industrial areas. The statisticalanalyses of the results show no significant differences betweenthe surface samples and the 35 cm deep samples from all three areas. Lead, zinc and copper (soluble and total fractions) aresignificantly higher, and pH significantly lower, in the samples coming from the contaminated and vacant industrial areasthan in samples coming from the clean area. Total lead and cadmium are significantly higher in the vacant industrial areas(150 g kg-1 Pb and 9.3 g kg-1 Cd) than in the contaminated areas (5.2 g kg-1 Pb and 2.1 g kg-1 Cd).Iso-concentration maps have been prepared in order to correlatethe presence of metals with the industrial and mining activities in the region under study. These maps show a clear relationship between human activities and metal concentrationgradients, with peaks corresponding to both active and abandoned industrial and mining facilities.  相似文献   

2.
Abstract

Domestic sewage sludge applied to farm fields at a rate of 44.9 kg/ha in a mixture with lime and sawdust was found to increase the soil levels of cadmium, chromium, copper, lead, mercury, nickel and zinc. The average levels in sludge treated soil were: 0.11, 0.56, 3.59, 2.72, 0.068, 1.49 and 2.57 ppm, respectively. The increases were small and the overall loading factors were well below recommended maximums. The uptake of these heavy metals by grass and legume plants was variable with cadmium, copper and zinc levels being higher in those plants growing in the sludge treated soils but only copper was significantly higher. The heavy metal contents found were all within the levels normally found in grass and legume plants. The higher mean concentration in plants growing on the sludge treated soils were cadmium 0.495; chromium 1.22; copper 12.3; lead 1.54; mercury 0.022; nickel 4.08 and zinc 28.4 ppm.  相似文献   

3.
通过向供试土壤中添加CuSO4、ZnSO4、Pb(Ac)2、HgCl2以模拟受污土壤,研究接种于其中的微小双胸蚯蚓对重金属的富集作用。以不加重金属盐类为对照,分别研究了不同培养时间和不同重金属浓度对富集量的影响。结果表明,蚯蚓对各种重金属的富集量随着培养时间的增加而变化,且对不同重金属最大富集量的出现时间也不相同。在第2周时蚯蚓对Cu、Pb富集量达到最大,而对Zn的富集量在第4周时达到最大。与Cu、Zn、Pb的富集量相比,蚯蚓对Hg没有明显的富集作用,且对Hg的最大富集量时间不明显。在其耐受浓度范围内,蚯蚓对重金属的富集量随着重金属浓度的增加而增加,且蚯蚓对重金属的吸收顺序为:Zn〉Cu〉Pb〉Hg,说明了微小双胸蚯蚓对Cu、Zn、Pb、Hg4种元素有一定的忍耐和富集能力,但其对重金属的忍耐和富集能力是有选择性的,说明不同重金属表现出的毒性是不一样的。研究结果初步推断,影响蚯蚓对重金属富集作用的主要原因可能是体内酶的作用,不同重金属可以从多方面干扰了动物机体内的生理生化功能。  相似文献   

4.
内蒙古草原白乃庙铜矿区土壤重金属污染特征研究   总被引:4,自引:0,他引:4  
对位于内蒙古荒漠草原上的白乃庙铜矿采选矿区土壤和尾矿区周围土壤重金属污染状况进行了调查研究。结果表明,矿区土壤中Cu、Cr、Ni、Fe和Mn浓度均高于内蒙古土壤平均值。单因子指数法评价结果表明,五个调查区域土壤都受到了重金属Cu、Cr、Ni、Mn、Fe的污染,其中Cu为重污染,Cr、Ni、Mn、Fe为轻污染,Pb为安全级别,Zn和As只对某些区域有轻污染。综合污染指数法评价结果表明,五个调查区域的土壤重金属污染等级均属重污染,主要贡献元素是Cu,其次是Cr、Ni、Mn、Fe,这与尾矿砂中这些重金属的浓度是相对应的。由于周边地形复杂,多为低山丘陵,所以该地区主导风向对于尾矿库区不同方向土壤重金属污染水平的影响差异并不显著。  相似文献   

5.
Silver, arsenic, cadmium, chromium, cobalt, copper, mercury, lead, and zinc were determined monthly during 2004–2008 at 11 sites in the Kura–Araks river system, Azerbaijan. Suspended fractions of the elements were studied at the five sites experiencing the highest load. Metal concentrations varied moderately at each site but differed substantially between sites. Sites near the borders with Armenia and Georgia were most polluted, both with respect to soluble concentrations and percentage transported in suspended form. Lower parts of the Kura river were shielded from metal contamination by an upstream reservoir acting as a metal trap. Corresponding removal was not evident in Araks, its main tributary, where particularly high concentrations of arsenic were observed. At the most contaminated sites, more than 60% of cadmium, cobalt, chromium, copper, manganese, nickel, lead, and zinc was transported in suspended form whereas arsenic and molybdenum occurred mainly in soluble form. Dynamics of metals in the Kura–Araks water/sediment system should be further studied to meet future problems.  相似文献   

6.
Background, Aim and Scope   Environmental contamination by heavy metals affects microbial communities. The number of single and multiple heavy metal resistant bacteria may be an indictor of the level of contamination. This paper details the isolation and characterisation of metal resistant microorganisms isolated from rhizosphere/soil samples obtained from an abandoned zinc, lead and copper mine and a local unaffected site. This data was compared to the level of heavy metal in the soils to establish the effect of metals on the microbial community and to determine the relationship between pollutant levels and resistant strains. This paper outlines the diversity of transferable resistance determinants between both sites and details the levels of heavy metal resistant bacteria and those expressing transferable multiple heavy metal tolerance.Methods   The sample sites were located in Co. Galway, Ireland. The first sample site (site A) was a former lead, zinc and copper mine, which was closed in 1961 due to exhaustion of ore. The second site (site B) was located two and a half kilometres from the mining site and was not affected by the mining operations. Composite soil samples were characterised for general soil matrix composition, organic content, pH and general chemical parameters. The soil was also enumerated for the total viable heterotrophic counts and tested on Pseudomonas selective agar (PSA) for total Pseudomonas counts and Sucrose Asparagine (SA), which is semi-selective for fluorescent Pseudomonas.Results and Discussion   Samples from both site A and site B were analysed by atomic absorption spectrophotometry for the presence of heavy metals. In the case of copper, which has a Dutch list recommended minimum permissible level of 190 µg/Kg dry weight, the levels detected at site A were 1270 µg/Kg dry weight while site B was detected at 36 µg/Kg. The arsenic levels detected at site A were eight times the permissible level (416 µg/Kg) while only half the permissible level was found at site B (13 µg/Kg). Zinc concentrations were also high at site A (4460 µg/Kg) while at site B (553 µg/Kg) they were well below the Dutchlist guidelines (720 µg/Kg). A large number of heavy metal tolerant strains were isolated from both sites. 270 isolates (site A (170) and site B (100)) were screened against 8 metals to examine the extent of multiple resistance. 82% of the strains from site A were found to be resistant to 5 metals. A total of 18% showed resistance to all 8 metals and of those examined only 4% were resistant to only one metal. In contrast isolates from site B showed no multiple resistance to more than 5 metals, while 62% showed resistance to individual metals only. Site A had a higher level of multiple heavy metal resistance strains. Stains isolated from site A had 23 (14%) isolates resistant to zinc, copper, nickel, arsenic and cobalt and site B had no bacteria resistant to all five of these selected metals. The transferability of heavy metal resistance was investigated in the case of 60 multiple heavy metal resistant isolates taken from site A and 50 multiple resistance isolates from site B. Transfer was only detected in isolates from site A, 13% showed transfer and expression of copper, zinc and arsenic resistance determinants. In most cases the transconjugants only expressed resistance to copper, zinc and arsenic, which were the metals, used for selection. This co-transfer of all three determinants suggests a genetic link between these resistance determinants.Conclusion   Heavy metal resistant bacteria are present in both sites, however, the number and presence of multiple transferable resistance phenotypes are confined to the isolates from the heavy metal contaminated site. The presence of high levels of heavy metals selects these multiple resistance phenotypes. Within these communities there seems to be little diversity between the microorganisms, which provides a hugely preferable environment for gene transfer of such metal resistant determinants.Recommendation and Perspective   The experiments have shown a microbes ability to mobilize heavy metal determinants and a relationship between heavy metal resistance and metal contamination has been identified These multiple heavy metal resistant bacteria could eventually be used for detection and qualification of the level of heavy metal-polluted soil/water environments.  相似文献   

7.
The use of programmable furnace in preparing samples for determining cadmium, lead, copper, and zinc by differential pulse anodic stripping voltammetry or atomic absorption spectrophotometry is convenient and time-saving. Recovery data for these 4 metals in various foods (tuna, sardines, and milk) were 93-96% for 0.01-1 ppm cadmium, 96-114% for 0.05-5 ppm lead, 100-108% for 2-10 ppm copper, and 97% for 10 ppm zinc.  相似文献   

8.

Purpose  

Despite the decline of metal mining in the UK during the early 20th century, a substantial legacy of heavy metal contamination persists in river channel and floodplain sediments. Poor sediment quality is likely to impede the achievement of ‘good’ chemical and ecological status for surface waters under the European Union Water Framework Directive. This paper examines the environmental legacy of the Dylife lead/zinc mine in the central Wales mining district. Leachable heavy metal concentrations in the bed sediments of the Afon Twymyn are established and the geochemical partitioning, potential mobility and bioavailability of sediment-associated heavy metals are established.  相似文献   

9.
M. J. KHAN  D. L. JONES 《土壤圈》2009,19(5):631-641
Soil samples from a historic copper mine tailing site at the Parys Mountain,North Wales (UK) were amended with green waste compost (GC),GC+30% sewage sludge (GCS),lime and diammonium phosphate (DAP),to determine the effect of amendments on DTPA-and Ca (NO3) 2-extractable metals in the mine tailing and on the phytoavailability of heavy metals by a lettuce (Lactuca sativa L.).Both compost were added at the rate of 10% by weight,lime was added as calcium carbonate equivalent (pH = 7) and DAP at a 2300 mg kg-1 soil level.The experiment was arranged in randomised complete design with three replicates in pots under control environment.Addition of lime resulted in the largest reduction in metal extractability with DTPA and Ca (NO3) 2 and phytoavailability of Cu,Fe and Zn while DAP was effective in lowering Pb extractability and phytoavailability.With exception of Zn,all other metals extracted decreased with time after amendment applications.The distribution of heavy metals between and within the four procedures of potentially bioavailable sequential extraction (PBASE) varied significantly (P < 0.001).Stronger relationships were noted between the metals extracted with PBASE SE1 and Cu,Pb (P < 0.01) and Fe (P < 0.001) in the lettuce.These results indicate that addition of lime is sufficient to restore the vegetative cover to a high metal mine waste while DAP is good for stabilizing Pb,but its detrimental role on plant growth and the risk associated with presence of N in DAP (through N leaching) may restrict its chances for remediation of contaminated sites.  相似文献   

10.
This paper presents the results of determining the pseudo-total concentration of five heavy metals in the soil on which the destruction of ammunition, mines, and explosive devices is carried out by the method of open detonation. In the analyzed area, the concentrations of cadmium, lead, nickel, copper, and zinc were determined, while from the physical properties of the soil were determined the granulometric composition and the pH. The aim of the study is to determine the origin and total load on heavy metals and, based on that, to assess the dangers and impact of the site in terms of the soil pollution by heavy metals. In accordance with the regulations of Bosnia and Herzegovina, the results of the soil testing showed a significant load of copper (up to seven times) and cadmium (up to six times), and exceeding the allowed values for nickel and zinc in some places. Lead was the only metal whose concentration was within the maximum allowed and according to that the soil was classified as unpolluted. A sample of soil from the edge of the pit is the only sample in which all heavy metals, except Ni, were within the maximum allowable concentration. In regard to the concentration of the examined metals, the soil of the pit is classified as medium polluted from the aspect of copper, cadmium, and nickel and highly contaminated with zinc. The concentrations of copper and zinc in the examination area correspond to contaminated soil that represents ecological risk, which requires soil remediation.  相似文献   

11.
This study focused on the analysis of metals in water and fish from Nairobi River. Water from Kikuyu, Kawangware, Chiromo, Eastleigh, Njiru and Fourteen Falls along the Nairobi River was analyzed for the presence of metals. Most of the metal levels in water were below the critical limit of World Health Organization and Kenya Bureau of Standards except for lead, chromium, iron and manganese. Isolated cases of mercury and aluminium pollution were recorded. Except for iron, sodium and potassium, there was no significant difference in the concentration of metals at different sites. This study also analyzed metal levels in fish organs and tissues of fish caught from downstream (Fourteen Falls). The highest zinc concentration (360 μg/g) was in the scales, copper recorded the highest concentration in the kidney (45 μg/g), while cadmium recorded high values (167 μg/g) in the heart. Lead recorded high values (178 μg/g) in the heart and mercury recorded high values also in the heart (1000 ng/g). Most of these organs, are however, not eaten by man as food. Although metal levels were within normal levels in the water at Fourteen Falls, mercury, copper, lead and iron recorded higher than accepted levels in some fish organs. This calls for caution in the consumption of fish from Fourteen Falls.  相似文献   

12.
Soils from a heavy metal contaminated southeast Kansas mining site were characterized for microbial resistance to zinc, cadmium, and lead. Plant availability indices (DTPA-extractable) for zinc were very high in the waste material (610 Μg g?1), while levels of lead and cadmium were more moderate, 45 and 4.3 Μg g ?1, respectively. Soil contamination decreased with distance from the mine tailings or ‘chat’. In the rhizosphere, bacterial resistance to zinc and cadmium increased as the DTPA-extractable plant availability indices increased. Mycorrhizal root colonization was not affected by the heavy metal concentration in the soil. The established vegetation in the contaminated area included warm- and cool-season grasses as well as forbs and sedges.  相似文献   

13.
采用野外采样系统分析法,研究了不同年限废弃地野艾蒿对Cu、Zn、Pb、Cd的富集与分布。结果表明,不同年限废弃地土壤中重金属的含量随着废弃年限的增加而减少,野艾蒿对Zn和Pb的富集量较大,不同年限废弃地中野艾蒿和土壤Cu、Zn和Pb的含量之间呈极显著正相关,野艾蒿对重金属的吸收、富集有随土壤中重金属含量升高而增加的趋势。野艾蒿的不同部位在不同年限废弃地中累积不同重金属的能力不同,除3 a废弃地野艾蒿中Pb的含量地上部分小于地下部分外,其他环境中重金属含量都表现为地上部分大于地下部分。野艾蒿对4种重金属都有不同程度的转运能力,Cu在不同年限废弃地的生物富集系数均为最大,野艾蒿对Cu、Cd转运能力较强。野艾蒿根系对Pb有弱的滞留效应为36.59%,对Cu、Cd、Zn没有滞留效应。综合分析结果表明,野艾蒿能吸收富集多种重金属并且具有耐重金属的特性,基于其具有生物量较大、生长速度快的特点,作为重金属污染的修复植物具有较好的应用前景。  相似文献   

14.
广东省典型区域蔬菜重金属含量特征与污染评价   总被引:8,自引:0,他引:8  
以广东省典型区域湛江市、中山市、珠海市、东莞市、惠州市和佛山市顺德区为研究对象,通过对其大型蔬菜基地生产中5类22种蔬菜171个样品中8种重金属元素进行检测,用国家蔬菜卫生标准计算污染指数并进行评价。结果表明:蔬菜中Cu、Zn、Ni、Cr、Pb、Cd、As和Hg的平均含量分别为0.6718、3.7431、0.1928、0.1451、0.0776、0.0205、0.0825和0.0022mgkg-1,其中有13.45%的蔬菜样品受到不同程度的重金属污染,Cd和Pb是蔬菜中主要污染元素;叶菜类蔬菜中重金属含量和综合污染指数都高于豆类、块根类、瓜类和茄果类等类型蔬菜;蔬菜中的重金属含量存在着复合污染关系。  相似文献   

15.
Monitoring data have been utilised to examine how well sedimentsreflect changes in industrial discharges of metals over time.One aim was to assess the role of selective transport andsedimentation in regulating the spatial distribution of themetals in the sediments, and how this could affect trendmonitoring. The results showed a significant decrease insediment concentrations of zinc, lead copper and mercury overtime in accordance with the reductions of the industrialdischarge. Copper seemed to favour terrestrial organic matterfor adsorption, which primarily settles out in the inner part ofthe estuary. Zinc and lead followed the fine fraction togetherwith organic carbon and settled out in the outer part of theestuary. Mercury showed the same, though there was nocorrelation to organic carbon. The innermost part of the estuaryhad a patchy distribution of zinc, copper and mercury, but notlead due to its diffuse supply. When reductions in sedimentconcentrations are large, selectivity in transport andsedimentation has little influence on the possibility ofdetecting significant trends from one year to another. When thereductions are less, it becomes increasingly important to focuson sampling in the likely main deposition areas for eachspecific metal.  相似文献   

16.
以大冶典型铜矿区为中心,辐射周边农田,探索农田土壤重金属污染特征及重金属在油菜中的积累变化规律。结果表明,以湖北省土壤背景值进行评价,土壤受到重金属不同程度的污染,其中Cd严重超标,Cu次之;采用国家二级标准进行评价,Zn、Cr和Pb未对土壤造成污染。进行内梅罗综合污染指数法评价发现,以土壤背景值为评价标准,各采样点均达到重金属严重污染水平;以国家二级标准评价时,只有2号采样点土壤属于中度污染水平,其他样点土壤都受到了较为严重的重金属污染。矿区农田油菜各部位重金属含量变化幅度较大,包括Cu、Pb、Zn、Cd和Co在内的5种重金属含量分布规律都是茎叶〉籽粒≈根,Mn则是籽粒〉茎叶〉根。油菜地上部植株中Cu、Pb、Zn、Cd含量均超出食品卫生标准最高限值,且Cd、Pb超标倍数远大于Cu、Zn。富集系数变化规律为Mn〉Zn〉Cd〉Ni〉Cu〉Pb垌Co。  相似文献   

17.
Effect of the heavy metals chromium, nickel, copper, zinc, cadmium, mercury and lead on uptake and translocation of K and P by young barley plants The uptake of potassium and phosphate into the roots and shoots of 7 days old barley plants from double-labelled (42K, 32P) nutrient solutions containing chromium, nickel, copper, zinc, cadmium, mercury or lead (10?6 - 10?4 moles/1) was measured in a constant environment after 5 hours, in order to compare early stages of toxicity. K and P uptake and translocation were inhibited by the 7 heavy metals to a different extent; K was more affected than P, and translocation of both nutrients into the shoots was more inhibited than uptake into the roots. Plants showed no visible injuries. Mercury had by far the greatest effect, zinc was almost ineffective: K uptake e.g. was reduced to 21% of the control by 10?4 moles Hg/l, but only to 97% by the same amount of Zn, and P translocation was reduced to 8% by Hg, but was not affected by Zn. The least significant effect of Hg was detectable at a concentration of 4.10?7 moles Hg/l ( = 0,08 ppm) in the nutrient solution, the effect of Zn only above 10?4 moles Zn/l ( = 6,5 ppm). Arranging the tested heavy metals according to their effects leads to the sequence Hg > Pb > Cu > Cd > Cr > Ni > Zn which corresponds – apart from two deviations – to the electrochemical series of the elements.  相似文献   

18.
The increasing number of cemeteries has caused concern about the possibility of releasing hazardous chemicals and metals into the surroundings. Moreover, many studies use cemeteries for 'background' sampling. This study attempts to identify whether cemeteries are indeed good 'background' areas, or whether they themselves are sources of contamination. Possible contaminants include poisonous chemicals, such as arsenic and mercury, which were used in past embalming and burial practices, which used: formaldehyde from current embalming practices; varnishes, sealers, and preservatives used on wood coffins; and lead, zinc, copper, and steel from metal coffins. This study reports on adsorbed metals in a fine-grained soil from a large cemetery in Northwest Ohio. Metal analyses were performed by atomic absorption and inductively coupled plasma spectrometry. This preliminary investigation revealed numerous possible sources of contamination, and the data support the need for further research. The results of zinc, copper, lead, and iron reveal an increase in concentrations on-site as well as with depth, especially at the burial depth. Dramatic increases in arsenic indicate contamination from embalming fluids or wood preservatives. This study warrants a concern for the quality of soil, groundwater, and nearby surficial water systems.  相似文献   

19.
Artisanal gold mining in the Ponce Enríquez, Portovelo-Zaruma and Nambija areas of Ecuador has resulted in extensive contamination of the fluvial environment by mercury (Hg) andpotentially toxic ore-related elements including arsenic (As),cadmium (Cd), copper (Cu), lead (Pb) and zinc (Zn). Thisoccurs principally through the fluvial dispersion ofcontaminated mineral processing wastes and recycling of Hgsublimated during the burning of amalgam. Mercuryconcentrations in filtered (<0.45 μm) surface waters do notexceed the WHO Drinking Water Guideline value and the USEPAWater Quality Criteria for the Protection of Aquatic Life.Criteria for other potentially harmful elements are, however,exceeded by a wide margin in the Ponce Enríquez (As, Cu,Zn) and Portovelo-Zaruma (Cd, Cu, Zn) districts, but not inthe Nambija area. The Environment Canada sediment quality HgToxic Effect Threshold for the Protection of Aquatic Life isexceeded in all three mining areas. As, Cd and Cu in manysediment samples from the Ponce Enríquez and Portovelo-Zaruma districts exceed Sediment Toxic Effects Thresholds byfactors of 10 to >1000. The results highlight the need toensure that contaminated sediment and water do not entercommercial banana plantations and shrimp ponds downstream ofthe Ponce Enríquez mining district.  相似文献   

20.
Cyanide and heavy metals were accidentally released from a mine waste lagoon in Romania into tributaries ultimately draining into the Tisza River. Within two months of the cyanide accident two subsequent heavy metal waste spills further contaminated the Tisza River, followed by severe spring flooding, which potentially spread the contamination to soils adjacent to the river. Flood plain soils and shoreline sediments were sampled from two locations on the middle Tisza River and a reference site to conduct a preliminary assessment of metal content and toxicity. Ten-day sediment toxicity tests were conducted with the amphipod,Hyalella azteca and 24 h soil toxicity tests were conducted with the nematode (Caenorhabditis elegans). High concentrations of cadmium, copper, zinc, lead and arsenic were detected in soil and sediment samples. However, no mortality was observed inHyalella exposed to Tisza River sediments and only up to 27% mortality of C.elegans was observed in flood plain soils. Low mortalities are attributed to reduced metal bioavailability caused by high soil cation exchange capacities and possible interactions with sediment organic matter or sulfides. Future studies should focus on factors that alter metal bioavailability and their relationship to potential toxicity of organisms exposed to Tisza River sediments and flood plain soils.  相似文献   

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