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21.
Twenty-six groundwater samples were collected from the Eastern Thessaly region and analysed by ICP-ES for these elements: Al, As, P, Pb, Zn, Mn, Fe, Cr, Sb, Cu, Na, Br, Cl, Si, Mg, Ag, Be, Bi, Dy, Er, Eu, Au, Ge, Ho, In, Ir, Os, Pt, Re, Rh, Ru, Lu, Hf, Hg, Tm, Zr and Nb. The objectives of the study were to assess the level of water contamination with respect to the EC and the USEPA health-based drinking water criteria. The geology of the studied area includes schists, amphibolites, marbles of Palaeozoic age, ophiolites, limestones of Triassic and Cretaceous age, Neogene and Quaternary deposits. The element ranges for groundwater samples are: Al 7–56 μg l−1, As 1–125 μg l−1, Br 6–60 μg l−1, Cl 500–25,000 μg l−1, Cr 1–6 μg l−1, Cu 1–15 μg l−1, Fe 10–352 μg l−1, Mg 2,940–40,100 μg l−1, Mn 0–8 μg l−1, Na 3,650–13,740 μg l−1, P 20–48 μg l−1, Pb 0–7 μg l−1, Sb 0–21 μg l−1, Si 3,310–13,240 μg l−1 and Zn 7–994 μg l−1. The results of groundwater analyses from the region of Eastern Thessaly showed elevated concentrations of As and Sb. Factor analysis explained 77.8% of the total variance of the data through five factors. Concentration of Br, Cl, Mg, Na and Si is directly related to the presence of saltwater in the aquifer, so grouping of these variables in factor 1 probably reflects the seawater intrusion. Al, As and Sb are known to form complexes in the environment, so grouping of these elements in factor 2 indicates their similar geochemical behaviour in the environment. The high negative loading of Mn in factor 2 indicates the presence of manganese oxides–hydroxides in the study area. Pb and Zn are associated together in sulphide mineralisation; so grouping of these elements in factor 3 reflects the sulphide mineralization paragenesis in the Melivoia area. P and Cu are associated together in phosphate fertilizers; so grouping of these variables in factor 4 could be related to agricultural practices. Cr, Fe, Mn and Mg are associated together in iron and manganese oxides–hydroxides and the weathering products of the olivine of the ultrabasic rocks; so grouping of these elements in factor 5 reflects the lithology of the area. There is a natural contamination of groundwaters with elevated concentrations of As and Sb due to the presence of the arsenopyrite and stibnite mineralisation in the Melivoia, Sotiritsa and Ano Polydendri areas. Contamination over the health-based drinking water guidelines given by EC and EPA has been investigated from nine sampling sites out of 26 of Eastern Thessaly region. 相似文献
22.
Mercury speciation and mobilization in contaminated soils of the Valle del Azogue Hg mine (SE,Spain) 总被引:1,自引:0,他引:1
Hg mobilization from contaminated soils and mine wastes was the source of environmental contamination in the Valle del Azogue
mining area. We researched solid-phase speciation and aqueous mobility of Hg through Scanning electron microscopy-energy dispersive
X-ray spectroscopy and electron probe microanalysis analysis, solid-phase-Hg-thermo-desorption (SPTD) and laboratory column
experiments. We found that in contaminated soils and mine wastes, the predominant Hg species was cinnabar (HgS), mainly formed
from the weathering of Hg-rich pyrite, and metallic Hg (0) in the matrix, whereas in calcines and tailings the dominant species
was metallic Hg (0). The mobilization of Hg in the aqueous phase seems to have originated from the dissolution of elemental
Hg (0) present in soils and wastes, reaching concentrations of up to 67 μg l−1, and showing a higher long-term environmental potential risk, in addition to atmospheric emissions. 相似文献
23.
ZHANG Jian-min ZHAO Yong-zhong XU Jing HUANG Juan The Logging Company Jilin Petroleum Group Co. Ltd Songyuan Jilin China 《吉林大学学报(地球科学版)》2006,(Z2)
吉林油田同位素吸水剖面测井采用~(113)In同位素追踪技术,根据同位素追踪过程解释基本可以判断配水层段吸水情况。但是在注水井存在沾污、大孔道以及串槽等影响时,吸水面积确定比较困难。在同位素测井中增加井温、流量参数,通过多参数综合解释,不仅可以对沾污影响进行合理校正,确定准确的小层吸水量,而且能够正确判断各级封隔器、配水器的工作情况,在地层存在大孔道的情况下,确定地层的吸水面积。吸水剖面综合解释方法在吉林油田已普遍应用,见到明显的效果。 相似文献
24.
YU Jie Ursula Pietrzak Jim Peterson 《地球空间信息科学学报》2005,8(4):257-261
In that orcharding in early-to-mid twentieth century southeastern Australia involved use of certain heavy metal and As compounds in regular pest-control spray procedures, some interest attaches to the possibility that these landparcels are underlain by soils with above-background Cu, Pb and As levels. Interpreta- tion of Land-cover changes allowed land parcels previously occupied by orchards to be identified in the 1950s through time-series air-photos. A comparison of soil analysis results referring to soil samples from control sites, and from land parcels formerly occupied by orchardists, shows that contamination (above-background) levels of cations in the pesticides can be found in the top 6 cm of former orchard soils. It is clear that digital spatial data handling and culturally-informed air photo interpretation has a place in soil contamination studies, land-use planning (with particular reference to re-development) and in administration of public health. 相似文献
25.
武汉市区第四系含水层地下水有机污染敏感性研究 总被引:14,自引:0,他引:14
在详细调查武汉市水文地质条件和地下水污染现状的基础上,获得了高精度的武汉市水环境中微量有机污染物的组成数据。所检测出的有机组分达30余种,以苯及相关苯系物为主,污染程度较高的地下水主要分布在人口密集区和工业,商业区,应用改进的DRASTIC模型-地下水污染敏感性评价模型,在GIS平台上,编制了武汉市区地下水污染敏感性分区图。根据其评价结果,建议集中对那些敏感性相对较高的区域采取有效的环保措施,开发利用时应作出风险评价。 相似文献
26.
This paper assesses the agricultural land resources of Guiyang City by means of GIS,on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicatror.he results suggest that most of the agricultural land resources are of good quality,However,there are 17.11km^2 dry land and paddy field,which belong to the region of serious heavy metal contamination and are not fit for planting crops.At the same time,the high quality plowland,which is suitable for cultivation,has decreased nearly by 1/3 due to soil heavy metal contamination.These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City. 相似文献
27.
建立了一个数学模型来预测多氯联苯湿地生物降解过程。该模型全面考虑了多氯联苯湿地生物降解的各子过程,包括:吸附/解吸、土壤屏蔽、扩散和生物降解,利用模型,预测了多氯联苯湿地生物降解的规律性及处理时间、处理终点;利用Monte-Carlo法,进行了多氯联苯湿地生物降解污染风险分析,结果表明,在采用基地现有处理方式的情况下,经过8年处理,土壤中4-Cl-PCBs不低于69.4%被降解的可能性为75%,此时土壤中能够继续污染外部环境的4-Cl-PCBs部分不超过10.9%的可能性为75%;土壤中4-Cl-PCBs全部生物降解完毕所需处理时间不超过16.20年的可能性为75%,最后被土壤不可逆屏蔽的残余物不超过20.9%的可能性为75%。 相似文献
28.
被污染土壤的植物修复研究 总被引:11,自引:1,他引:11
植物修复是利用植物吸收、降解、挥发、根滤、稳定、泵吸等作用机理,达到去除土壤、水体中污染物,或使污染物固定以减轻其危害性,或使污染物转化为毒性较低化学形态的现场治理技术.植物修复对于重金属污染土壤的治理修复具有重要意义.已有研究在累积与超累积植物的寻找筛选、植物对重金属等有害物的耐毒和解毒机理、植物修复现场环境调控及根际处理技术等方面取得了大量成果.现代分子生物学、基因工程技术发展有可能使植物修复技术取得重大突破. 相似文献
29.
区域土壤环境地球化学研究——异常成因判别·环境质量·污染程度评价的思路与方法 总被引:8,自引:2,他引:8
从概念内涵和应用目标出发,认为土壤环境地球化学质量评价应该分为质量现状和污染程度两个方面.在此基础上探讨了区域地球化学资料在土壤环境现状质量评价、异常成因识别、污染元素累积速率和土壤污染程度评价研究的基本思路和方法. 相似文献
30.