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1.
Lake Vegoritis, in the northwestern part of Greece, accepts the pollutants of the municipal and industrial activities in the area (lignite burning power plants and a nitrogen fertilizer factory). The PIXE external beam technique was used for the elemental analysis of water and sediment samples in order to determine the load of metals in the lake and obtain information for managing its environment. From our results it is deduced that the anthropogenic activities in the drainage basin do not have so far any significant impact on the Vegoritis Lake, as far as the elements studied are concerned. However, there is indication that other pollutants are introduced, mainly along the Solou stream, which cause precipitation of the metals.  相似文献   

2.
In the industrial zone of Ptolemais, Greece there are two coal-fired power plants, one nitrogen-fertilizer producing plant and a factory making coal-bricks. The industrial and the municipal waste effluents of this area are discharged into the lake Vegoritis via a small stream named Solou. Water and core or grab sediment samples taken from the Solou stream and Vegoritis Lake were analyzed for metallic elements by the proton induced X-ray emission (PIXE) method and the different pollution sources of the area under study, as far as metal pollution is concerned, were tentatively identified. The communities contribute to the pollution with loads of Pb and Ni; Ca, Cr, and Mo are contributed mainly by industries, while Fe, Zn, Mn, Sr, and Br have their origin to both sources. Also the sediment enrichment factors (SEF) are calculated and discussed.  相似文献   

3.
与煤有关的元素是有毒的和持久性的污染物,自从工业革命以来,主要是由点源排放在全球传播。华盛顿州生态部从华盛顿州东北部的深湖采集了一个沉积柱,以评估美国太平洋西北部最近的大气沉积变化。沉积柱被分为深度层段和210Pb测年。对每个截面的样品进行消化并使用ICP-MS进行金属和类金属的分析。数据显示最近砷、钡、硒和汞的浓度的增加。与1993年美国地质调查局怀俄明州弗雷蒙特冰川上部的冰芯数据、亚洲煤炭消耗数据和天气模式进行比较,表明向深湖沉积物输入的污染物是亚太地区燃煤活动的结果。最显著的是,自进行冰芯分析的1993年以来,深湖的汞沉积量从1996年的20 ppb增加到2014年的9470 ppb(增加了400倍)。  相似文献   

4.
太湖复合污染胁迫下生物体抗氧化标志物的响应   总被引:1,自引:0,他引:1  
采用清洁地饲养鲫鱼(Carassius auratus)为监测对象,采取主动生物监测法(ABM)对太湖北部湾复合污染区梅梁湖与贡湖进行为期3周的生物监测.结果表明,在有机、重金属复合污染条件下鲫鱼肌肉组织中抗氧化酶谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GP_X)与谷胱甘肽硫转移酶(GST)对污染物胁迫反应敏感,实验初期GSH出现显著抑制,而GP_X与GST出现显著诱导(P<0.05),实验后期均出现一定程度恢复,各监测点之间抗氧化酶没有表现出显著的差异.IBR综合分析表明,重金属离子对生物体抗氧化综合生物效应贡献最大,同时,浅水湖泊中风场的扰动影响不可忽略.  相似文献   

5.
This study emphasizes on identification of source and accessing the spatial variation of dissolved heavy metals (Cu, Cd, Fe, Ni, Pb and Zn) in the rivers of Sundarban Biosphere Reserve India, the UNESCO world heritage site. ANOVA (Analysis of Variance), PCA (Principal Component Analysis) as well as FA (Factor Analysis) are used for assessing the significant difference in means of metals concentration among the sites and understanding the sources of these pollutants. Three principal components with cumulative variance of 32, 55, and 73 %, show that Pb, Ni and Cd are closely associated with each other indicating an anthropogenic origin of these metals. Heavy metal evaluation index (HEI) values indicate that areas close to densely populated sites are affected by elevated metals concentration due to anthropogenic activities. The ratio between the concentration of Cd, Ni and Pb in sites and the maximum respective permissible limit for these metals for conserved habitat is Log10 normalized to understand the threats of these pollutants over the distributaries of Sundarbans. Pb pollution is prevalent in the areas that rely on the fossil fuel-operated boats, for transport, whereas higher Cd concentration is found in the areas dependent on rechargeable batteries to meet their energy demand. So these anthropogenic activities and mal-practices may be responsible for the heavy metal pollution in this region. The study concludes that gradual increase in metal pollution in river water due to anthropogenic activities, particularly Pb and Cd, could have a negative impact on the conserved flora and fauna of this ecosystem.  相似文献   

6.
A review of combinations of electrokinetic applications   总被引:1,自引:0,他引:1  
Anthropogenic activities contaminate many lands and underground waters with dangerous materials. Although polluted soils occupy small parts of the land, the risk they pose to plants, animals, humans, and groundwater is too high. Remediation technologies have been used for many years in order to mitigate pollution or remove pollutants from soils. However, there are some deficiencies in the remediation in complex site conditions such as low permeability and complex composition of some clays or heterogeneous subsurface conditions. Electrokinetic is an effective method in which electrodes are embedded in polluted soil, usually vertically but in some cases horizontally, and a low direct current voltage gradient is applied between the electrodes. The electric gradient initiates movement of contaminants by electromigration (charged chemical movement), electro-osmosis (movement of fluid), electrolysis (chemical reactions due to the electric field), and diffusion. However, sites that are contaminated with heavy metals or mixed contaminants (e.g. a combination of organic compounds with heavy metals and/or radionuclides) are difficult to remediate. There is no technology that can achieve the best results, but combining electrokinetic with other remediation methods, such as bioremediation and geosynthetics, promises to be the most effective method so far. This review focuses on the factors that affect electrokinetic remediation and the state-of-the-art methods that can be combined with electrokinetic.  相似文献   

7.
Lake water and fish livers and gills of sahar (Tor putitora), spiny eel (Mastacembelus armatus), African magur (Clarias gariepinus), and tilapia (Oreochromis niloticus) from Lake Phewa, Nepal, were assessed for the concentrations of trace metals/elements and persistent organic pollutants. The lake water was neutral with low ionic and metallic concentrations as compared to high-altitude lakes of Nepal. The four elements Cu, Zn, Se, and Cd had highest concentrations in livers, indicating uptake from diet, whereas four other metallic elements Cr, Mn, Ni, and Pb had highest concentrations in gills, indicating uptake from lake water. O. niloticus tended to have most of trace metals in the liver at higher concentrations than the other species but significant differences among the different species were found only for Mn, Ni, and Zn in the gills. A pilot study on the concentrations of persistent organic pollutants in muscle revealed that dichlorodiphenyltrichloroethane and related compounds were the dominant organochlorine pesticides, having highest concentrations in C. gariepinus and lowest in O. niloticus.  相似文献   

8.
应用物种敏感性分布法分析太湖及天目湖水体的生态风险   总被引:1,自引:0,他引:1  
采用物种敏感性分布法(SSDs法),应用水生生物急性和慢性毒性数据计算了31种污染物在水中和其中疏水物质在沉积物中的预测无效应浓度(PNECwater和PNECsed),通过收集以往报道的16种污染物在太湖和天目湖的环境浓度,用商值法求得物质的风险商并进行排序.结果发现:蒽、菲、萘、荧蒽、阿特拉津和马拉硫磷在太湖的梅梁湾和五里湖具有很大的生态风险;毒死蜱、三丁基锡氧化物和环己锡虽无环境浓度报道但很有可能具有风险.  相似文献   

9.
Bioremediation is an innovative and promising technology available for the removal and recovery of heavy metals from contaminated media. Bioremediation uses organisms to absorb heavy metals at low cost and with no secondary pollution. Bioremediation by macrofungi that degrade pollutants or wastes is referred to as mycoremediation. Macrofungi, like mushrooms, can produce enzymes and have the ability to degrade and accumulate a wide range of toxic metals. In this paper, the research status and advances in the field of mycoremediation using different mushroom species are reviewed. Generally mushrooms use three effective strategies to recover contaminated or polluted soils: biodegradation, bioconversion, and biosorption. Mushrooms can degrade and recycle wastes and pollutants to their mineral constituents and convert wastes, sludge, and pollutants into useful forms. In addition, they can uptake heavy metals from substrates via biosorption, which is a very effective method to reclaim polluted lands. Different wild and cultivated mushroom species are used in mycoremediation, which can degrade large quantities of organic and inorganic pollutants and produce vendible products. Mycoremediation is still in its infancy, but it has notable remediation potential for pollutants or metals in soil. Mushroom species that can biodegrade, bioconvert, or absorb pollutants and metals effectively should be given the highest preference. Further research is needed to verify that this method is an easy, cost effective,and eco-friendly tool.  相似文献   

10.
电子废物含有大量的金属、塑料和阻燃剂等物质,如果处理不当,电子废物将向环境排放种类繁多的有毒有害物质,从而产生严重的环境污染问题。近年来,国内外学者对电子废物处理所致的生态环境问题给予了相当的关注,已经开展了不少相关研究,这些研究主要集中在我国的几个电子废物处理处置典型地区。本文对近5年来的相关研究成果进行了系统综述,内容涉及电子废物处理处置过程中产生的主要环境污染物,电子废物处理处置活动所致的土壤、水体和大气的重金属和持久性有机污染物污染以及电子废物处理处置活动对动植物和人体的污染风险等,并提出将来关于电子废物研究中需要关注的问题。  相似文献   

11.
Heavy metals and soil microbes   总被引:1,自引:0,他引:1  
Heavy metal pollution is a global issue due to health risks associated with metal contamination. Although many metals are essential for life, they can be harmful to man, animal, plant and microorganisms at toxic levels. Occurrence of heavy metals in soil is mainly attributed to natural weathering of metal-rich parent material and anthropogenic activities such as industrial, mining, agricultural activities. Here we review the effect of soil microbes on the biosorption and bioavailability of heavy metals; the mechanisms of heavy metals sequestration by plant and microbes; and the effects of pollution on soil microbial diversity and activities. The major points are: anthropogenic activities constitute the major source of heavy metals in the environment. Soil chemistry is the major determinant of metal solubility, movement and availability in the soil. High levels of heavy metals in living tissues cause severe organ impairment, neurological disorders and eventual death. Elevated levels of heavy metals in soils decrease microbial population, diversity and activities. Nonetheless, certain soil microbes tolerate and use heavy metals in their systems; as such they are used for bioremediation of polluted soils. Soil microbes can be used for remediation of contaminated soils either directly or by making heavy metals bioavailable in the rhizosphere of plants. Such plants can accumulate 100 mg g?1 Cd and As; 1000 mg g?1 Co, Cu, Cr, Ni and 10,000 mg g?1 Pb, Mn and Ni; and translocate metals to harvestable parts. Microbial activity changes soil physical properties such as soil structure and biochemical properties such as pH, soil redox state, soil enzymes that influence the solubility and bioavailability of heavy metals. The concept of ecological dose (ED50) and lethal concentration (LC50) was developed in response to the need to easily quantify the influence of pollutants on microbial-mediated ecological processes in various ecosystems.  相似文献   

12.
尽管针对洞庭湖沉积物中重金属的研究工作较多,但缺乏针对其主要入湖口的研究。基于2014年12月和2015年6月对洞庭湖主要入湖口表层沉积物中重金属调查,分析了重金属含量的时空分布特征,并采用一致性沉积物质量基准法对其生态风险进行了评价。结果表明,Cd、Hg、As、Cu、Pb和Zn的平均含量分别为3.27、0.190、27.10、39.8、38.0和157.8 mg·kg-1,其大小顺序为ZnCuPbAsCdHg,Cd和As含量出现超过土壤环境质量三级标准的现象,是主要的重金属污染物。Cd、As、Pb和Zn等4种重金属含量的最高值均出现在湘江入湖口,Cu含量的最高值出现在资水入湖口,Hg含量以沅江入湖口最高,除Pb外,其他5种重金属在湘江和资水入湖口的含量均大于平均值,表明湘江和资水入湖口污染较为严重;汛期与非汛期6种重金属的含量均无显著性差异(P0.05)。6种重金属生态风险大小顺序为AsCdZnPbCuHg,各入湖口生态风险大小顺序为湘江入湖口资水入湖口沅江入湖口汨罗江入湖口澧水入湖口长江"三口"新墙河入湖口,其中湘江和资水入湖口为较高生态风险,其他入湖口为较低生态风险。入湖河流是洞庭湖湖体沉积物重金属污染的主要来源,在一定程度上,入湖河流沉积物中重金属的含量对洞庭湖湖体沉积物中重金属污染状况起着决定性作用,因此,洞庭湖流域重金属污染防控应以入湖河流为主,其中尤以湘江和资水为重点。  相似文献   

13.
基于盲数的水体沉积物潜在生态风险评价方法   总被引:2,自引:0,他引:2  
李如忠  洪天求  贾志海  刘路 《生态环境》2007,16(5):1346-1352
基于生态风险评价系统中多种不确定性共存或交叉存在的特性,将盲数理论应用于水体沉积物潜在生态风险的评价研究。在将Hakanson潜在生态风险指数模型参数定义为盲参数的基础上,建立了沉积物潜在生态风险评价的盲数模型,并提出了污染程度和潜在生态风险等级识别盲数可靠性计算模型。根据上述盲数模型,不仅可以得到沉积物污染程度和潜在生态风险的可能取值区间,也可以得到各区间相应的可信度水平,进而定量计算待评价对象隶属于各评价等级的主观可能性大小。作为案例,将上述模型应用于巢湖十五里河河口沉积物中重金属潜在生态风险评价的研究。在得到沉积物中单个重金属污染物(Hg,Cd,Pb,Cu,Cr)隶属于污染程度各等级和潜在生态风险各等级可信度水平的基础上,得出十五里河河口处于较高生态风险水平的结论,相应的可信度为0.626。实例研究表明,以盲数理论评价沉积物的潜在生态风险,理论上可行,评价结论可信。  相似文献   

14.
选择北部湾9个典型采样点,研究了潮间带沉积物中重金属和多氯联苯(PCBs)的分布特征和生态风险.分析结果表明,Hg、As、Cu、Pb、Zn、Cd、Cr等重金属和总PCBs的平均含量分别为0.100、10.00、19.89、45.97、208.65、0.098、17.86 mg.kg-1和1.48!g.kg-1.重金属和PCBs表现出不同的空间变化规律.相关性分析表明,北部湾潮间带的重金属主要来自人为污染;沉积物的粒度参数和有机质含量等性质特征是影响PCBs分布和迁移的重要因素;重金属和PCBs总量之间不存在明显的相关性.生态风险评价结果表明,PCBs和Cd是北部湾潮间带最主要的生态风险因子,Zn和PCBs是优势污染物;研究区域总体处于中等生态风险等级,表明沿岸港口和临海工业等人为活动已经对北部湾滨海地区造成了一定的环境压力.  相似文献   

15.

Goal and Scope

The heavy metal burden of the soil and of earthworms from representative long-term forest observation plots has been measured since 1984 as one component of the media-embracing environmental monitoring network of the State of Baden-Wuerttemberg. These investigations are aimed at elucidating and assessing adverse effects of pollutants on the soil biocenosis

Methods

So-called characteristic curves for the metals Cd, Cu, Ni, Pb, and Zn were developed for the assessment. Earthworm toxicity data and background values in soil served as criteria. This procedure facilitates a comparative assessment of different pollutants. The mobility of the metals, which greatly influences their bioavailability and toxicity, was taken into account for the effects assessment.

Results and Conclusion

Besides inventorying the heavy metals (Part 1), the question of threshold values for toxic reactions as well as for accumulation was raised. The metal concentrations were assessed in the soil with regard to its habitat function. The ecotoxicological assessment revealed that the heavy metal burden of the investigated plots lies within the background- or precautionary range, well below the screening value established here to indicate the effect threshold in earthworms. This result means that a pollution of the forest observation plots with the metals cadmium, copper, lead, nickel, and zinc is low or absent. Only the distribution of the lead content is centered slightly above background (but clearly below the toxicity threshold). This slight lead burden of the soil of the observation plots can be explained by emissions from motor vehicles. Investigations at sites that are contaminated with either chromium or copper or cadmium showed that an accumulation of these metals in the body of the worms can be observed only above a threshold concentration of several hundred micrograms of mobile metal per kilogram in the upper layer of the soil.

Recommendations and Perspectives

The hitherto unknown threshold values for the accumulation in the body of the earthworm should be statistically validated and extended to other elements. Further research is needed in order to build a well founded basis for the ecotoxicological assessment of soil pollution. Acute and chronic earthworm effect thresholds are neither available yet for arsenic, cobalt, and mercury nor for some other elements occurring less frequently as soil pollutants. Background values depending on the kind of rock have been measured so far for total chromium only. They are lacking for the more toxic chromium (VI) which is a frequent soil pollutant but naturally occurs in traces only.  相似文献   

16.
由于大量人类活动的影响,大气CO_2浓度持续增加,其中约1/3被海洋吸收,导致表层海水pH值降低和碳酸盐平衡体系波动,即"海洋酸化"现象。污染物的海洋环境效应一直是全球环境科学领域研究的热点。在实际环境中,海洋酸化往往与污染物共同存在并作用于海洋生态系统,且海洋酸化极有可能改变污染物的海洋环境行为从而影响其毒性效应。但现有研究大多针对海洋酸化或者污染物单独作用下的毒性效应展开,对海洋酸化与污染物的联合毒性效应的研究不足、亟待加强。为此,综述了近年来海洋酸化与典型污染物(重金属、有机污染物)及新型污染物(人工纳米颗粒)的相关文献,重点阐述了海洋酸化对污染物环境行为的影响和海洋酸化与污染物对海洋生物的联合毒性效应,指出当前的研究不足,并对未来的研究方向进行了展望。  相似文献   

17.
Sediment cores were collected from two remote subalpine lakes: the rather shallow (1.5 m) Little Ghost Lake at 2040 m elevation and the deeper, Great Ghost Lake (40 m) at 2150 m elevation. Different early diagenesis of metals were observed. the seasonally anoxic hypolimnion drives the annual iron redox cycle and causes the remobilization of metals in the mobile fractions of sediments in the Great Ghost Lake. These result in the redistribution of metals in the mobile fractions of sediment and poor correlation between metal concentrations. in the Little Ghost Lake, the shallow water column is always oxic with less change of metals in the mobile fractions of sediments. As a result, most metals have strong positive correlations with each other.

The distributions of metal/Al ratios, total metal contents and acid-leached metal concentrations in the near-surface sediments of these two lakes suggest that the anthropogenic inputs from the atmospheric fallouts in recent decades are one of the major factors affecting the distributions of metals such as cadmium, lead and, to a lessor extent, zinc. the Pb-206/Pb-207 ratios confirm the anthropogenic lead input in these surface sediments.  相似文献   

18.
Sediment cores were collected from two remote subalpine lakes: the rather shallow (1.5 m) Little Ghost Lake at 2040 m elevation and the deeper, Great Ghost Lake (40 m) at 2150 m elevation. Different early diagenesis of metals were observed. the seasonally anoxic hypolimnion drives the annual iron redox cycle and causes the remobilization of metals in the mobile fractions of sediments in the Great Ghost Lake. These result in the redistribution of metals in the mobile fractions of sediment and poor correlation between metal concentrations. in the Little Ghost Lake, the shallow water column is always oxic with less change of metals in the mobile fractions of sediments. As a result, most metals have strong positive correlations with each other.

The distributions of metal/Al ratios, total metal contents and acid-leached metal concentrations in the near-surface sediments of these two lakes suggest that the anthropogenic inputs from the atmospheric fallouts in recent decades are one of the major factors affecting the distributions of metals such as cadmium, lead and, to a lessor extent, zinc. the Pb-206/Pb-207 ratios confirm the anthropogenic lead input in these surface sediments.  相似文献   

19.
This article reviews both the pollution by the electrochemical industry and the use of electrochemistry to clean water. Main pollutants include Pd, Cd, Ni, Hg and other metals and cyanide as well as organic pollutants. The cause for water pollution by electrochemistry is due to the effluents from different electrochemical industries such as mercury from chlor-alkali industry; lead, cadmium and mercury from battery industry; heavy metals and organic contaminants from electroplating wastes; contaminants from corrosion processes; and persistent organic pollutants from the synthesis and use of pesticides, dyes and pharmaceuticals. Most pollutants can be successfully eliminated or converted to non-toxic materials by methods based on the electrochemical principles. Electrochemical depolluting methods are mainly electrodialysis, electrocoagulation, electroflotation, anodic processes, cathodic processes and electrochemical advanced oxidation processes.  相似文献   

20.

The rapid urbanization and industrialization is causing worldwide water pollution, calling for advanced cleaning methods. For instance, pollutant adsorption on magnetic oxides is efficient and very practical due to the easy separation from solutions by an magnetic field. Here we review the synthesis and performance of magnetic oxides such as iron oxides, spinel ferrites, and perovskite oxides for water remediation. We present structural, optical, and magnetic properties. Magnetic oxides are also promising photocatalysts for the degradation of organic pollutants. Antimicrobial activities and adsorption of heavy metals and radionucleides are also discussed.

  相似文献   

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