首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 109 毫秒
1.
在皖北矿区采取了2 2个深层地下水水样,测试Ag、Al、As、Ba等2 0种微量元素,建立了主成分分析模型。根据元素相关性、特征值与累计方差贡献率,进行了地下水的微量元素主成分分析和地下水主成分解释。在此基础上建立了皖北矿区主要突水水源4个主成分的判别表达式,从而得出结论:矿区地下水,特别是四含、太灰与奥灰3个突水含水层微量元素的质量浓度与4个主成分息息相关,可以简单地把第一、二、三、四主成分概括为地下水的溶滤作用、越流作用、河流补给作用、构造裂隙补给作用。   相似文献   

2.
A hydrogeochemical study was conducted on the groundwater of south Al Madinah Al Munawarah City, Saudi Arabia, to assess the quality of groundwater for drinking and irrigation uses. Groundwater samples have been collected and analyzed for major and some trace constituents from the study area. The nitrate concentration in most groundwater samples of the study area exceeded the safe limits for drinking purposes, whereas the concentrations of phosphate, boron, and trace constituents were below the maximum permissible limit for drinking purposes; Cr in two samples showed high content over the recommended limits of drinking purposes. Uncontrolled abstraction of groundwater in Abar Al Mashi area caused many environmental problems including water resource depletion and contamination. Correlations between chloride and major ions were positive and may be attributed to impact of agricultural activities on groundwater chemistry. Groundwater of the study area was classified into six water types. The chemical water types of groundwater in the study area contain CaHCO3 in the eastern and southeastern parts and NaCl in western and northwestern parts, reflecting different land use characteristics and pollution sources. Piper diagram showed that almost all the samples fall in one zone, indicating similar chemical signature. Groundwater can be used safely for drinking with special treatments to eliminate the effect of increased concentrations of total dissolved solids, nitrate, and chromium. The groundwater of the study area can be used safely for irrigation on clay soil; however, specific crops should be selected according to their salt tolerance.  相似文献   

3.
This paper refers to the development of a conceptual model for the management of a coastal aquifer in northern Greece. The research presents the interpretation and analysis of the quantitative (groundwater level recordings and design of piezometric maps) regime and the formation of the upcone within the area of investigation. Additionally it provides the elaboration of the results of chemical analyses of groundwater samples (physicochemical parameters, major chemical constituents and heavy metals and trace elements) of the area which were taken in three successive irrigation periods (July–August 2003, July–August 2004 and July 2005), in order to identify areas of aquifer vulnerability. The study identifies the areas where ion exchange phenomena occur, as well as the parts of the aquifer where the qualitative degradation of the aquifer system is enhanced. The paper, finally, assesses the lack of any scientific groundwater resources management of the area by the local water authorities, as well as the current practices of the existing pumping conditions scheme as applied by groundwater users.An erratum to this article can be found at  相似文献   

4.
《Applied Geochemistry》1999,14(1):27-39
One hundred and fifty Norwegian bedrock groundwater samples, from Bergen and from Vestfold (Oslofjord), have been analysed by ICP-MS techniques at two laboratories for a large suite of trace elements including rare earth elements (REEs) and Y. The bedrock lithologies include granites (dominated by the Permian Drammen Granite) and Permian latites/rhomb porphyries from Oslofjord, and Caledonian/Precambrian granitic and gneissic lithologies in the Bergen area. The REEs show good correlation with each other, with the exception of Eu. REEs generally show a weak negative correlation with pH. REE concentrations are highest in waters in acidic lithologies and generally decrease with increasing atomic weight. Yttrium, La, Ce and Nd are the most abundant REEs in the waters, with median concentrations exceeding 0.1 μg/l. On crustal (PAAS)-normalised plots, distinct geochemical signatures are observed for the different lithologies. Most groundwaters exhibit negative Eu anomalies on such plots, except for latitic waters from the Oslo area which show a positive Eu anomaly. Aquifer host-rock-normalised plots for groundwaters from Vestfold indicate minor enrichment in heavier REEs and depletion in Ce during water–rock interaction.  相似文献   

5.
Sewage effluent is often rich in toxic constituents leading to environmental hazard. Continuous discharge of sewage effluents into an agricultural training farm in University of Ibadan is polluting groundwater used for cultivation of vegetables and cereals, as also for drinking, thus posing risk to human health. The study area is underlain by Precambrian banded gneisses. The study is based on seven groundwater samples and twenty-three soil samples collected from seven trial pits. The samples have been analysed using AtomicAbsorption Spectrophotometric and Inductively Coupled Plasma- Emission Spectroscopy respectively.Water analyses data show that the concentrations of Fe, Pb and Cd have exceeded the WHO (2006) drinking-water quality guidelines. Correlation coefficient of water shows that the coefficient corresponding to zero has a percentage of 29, whereas 71 % of correlation is either from the same source or from different source of enrichment. The correlation analysis of soil samples shows that 92.9% of the elements have the same source. The enrichment factor and geo-accumulation analyses confirm enrichment of Cu, Cd, Fe, Pb, Zn, Sr, Ba, Mn, Ni and La concentrations contributing to the pollution. All the metals analysed in the soil sample from the farm have anthropogenic influence.  相似文献   

6.
The aim of the present work is to investigate the distribution of arsenic(As) in sewage ir-rigation area,to deduce the migration and transformation mechanism of As in soil and groundwater,and to infer the source of As in soil and groundwater.This study is carried out in a sewage irrigation area of the Pearl River Delta,China.Surface water samples,soil samples,and groundwater samples from sewage irrigation area were analyzed for As and other elements.As contents in water samples were analyzed by hydride gene...  相似文献   

7.
In this study, combining interpretations of conservative dissolved ions and environmental isotopes in water were used to investigate the main factors and mechanisms controlling groundwater salinization and hydrogeochemical processes in the Eastern Nile Delta, Egypt. Hydrogeochemical and isotopic study has been carried out for 61 water samples from the study area. Total dissolved solid (TDS) contents of groundwater are highly variable rising along flowpath from the south (410 mg/L) to the north (14,784 mg/L), implying significant deterioration and salinization of groundwater. Based on TDS and ionic ratios, groundwater samples were classified into three groups. In low-saline groups, water chemistry is greatly influenced by cation exchange, mineral dissolution/precipitation, anthropogenic pollutants and mixing with surface water. Whilst, in high-saline groups, water chemistry is affected by salt-water intrusion, reverse cation exchange and evaporation. The chemical constituents originating from saline water sources, reverse ion exchange and mineral dissolution are successfully differentiated using ionic delta and saturation index approaches. The δ18O–δ2H relationship plots on a typical evaporation line, suggesting potential evaporation of the recharging water prior to infiltration. Isotope evidence concludes that the groundwater have been considerably formed by mixing between depleted meteoric water recharged under different climatic conditions and recently infiltrating enriched surface water and excess of irrigation water. The δ18O data in conjunction with chloride concentrations provide firm evidence for impact of dissolution of marine-origin evaporite deposits, during past geologic periods, on groundwater salinity in the northern region. Moreover, the relation between 14C activities and Cl? concentration confirms this hypothesis.  相似文献   

8.
北京平原区永定河地下水系统地下水化学和同位素特征   总被引:1,自引:0,他引:1  
北京平原区永定河地下水系统位于北京市的西部.在该区采集了一个水文年的大气降水样,并对其中的D和18O组成作了分析;于旱季在该地下水系统中采集了大量地下水样,并对其中的八大离子浓度、D和18O组成、Sr浓度以及87Sr/86Sr比值作了分析.研究结果表明,研究区地下水的水化学类型较为单一;研究区地下水主要来源于大气降水入...  相似文献   

9.
An integrated hydrogeological investigation involving geological surface data, well data (lithostratigraphical and piezometric data) and the vertical electrical sounding (VES) method was carried out in Tataouine area, Southern Tunisia to characterize the hydrogeology and the geochemistry of the Krachoua Formation aquifer. The electrical data were used to differentiate lithostratigraphic units and characterize their hydrogeological potentialities. Major elements contents within groundwater samples were assessed and some plots and diagrams have been established in order to investigate the hydrochemical properties of this aquifer and the origin of its mineralization. The Krachoua aquifer exhibits a general drawdown of the piezometric level from 2004 to 2015 reflecting a dramatic decrease in groundwater resources due to increased groundwater abstraction during the last decades. Flow directions shows that the recharge of this aquifer considered as a free aquifer is directly ensured by rainfalls over the outcropping fractured limestones. The geometry of the Krachoua Formation aquifer is tectonically controlled and structured in horst and graben features that impacted greatly the hydrogeology and the hydrodynamics of the area. Subsequent thickness and facies variations within this aquifer influenced the reservoir quality and the groundwater flows. The increased values of salinity to the northwest of the study area seems to be mainly related to the dissolution of the Upper Liassic gypsum of Mestaoua Formation which outcrops widely and can be dissolute easily by meteoric water and contaminate the Krachoua aquifer. This fact is also supported by the sulfated and calci-magnesian chloride facies of this aquifer related to the dissolution of evaporitic rocks (gypsum, anhydrite, and halite). However low salinity values are recorded within the zone where these evaporitic rocks are relatively deep.  相似文献   

10.
Chennai is one of the four major metropolitan cities in India, and is located in the southeastern part of the country. The average rate of population growth of the city is 25 % per decade and this is recurrently reducing the green-covered area in the city. Exceptionally, during the post-economic liberalization period (i.e., between the years 1997 and 2007), the city lost up to 99 % of its green-covered areas at some parts. Subsequently, the Chennai City started to experience wide range of environmental issues, including groundwater pollution and the effects of groundwater depletion. As a consequence of these factors, a study was undertaken to determine the impact of urbanization on the groundwater quality. In the present study, groundwater samples were collected from 54 stations from the study area during the premonsoon and postmonsoon seasons for the year 2011–2012 and were analyzed for physico-chemical parameters and trace elements. The type of water that predominated in the study area was assessed based on hydrochemical facies. The study of the hydrochemical characteristics of the major ions in these waters shows that in premonsoon, the alkalis and the alkaline earth metals are found to be balanced by chlorides and bicarbonates and sulphates, respectively. Reverse ion exchange study illustrates that Ca, Mg and Na concentrations are interrelated through reverse ion exchange. Box and whisker plots illustrate the seasonal effect on the chemical parameters of the groundwater. Gibbs’ diagram reveals that the chemical composition of the groundwater in the study area is predominated by rock–water interaction. Besides, suitability of groundwater for irrigation was evaluated based on sodium adsorption ratio, Kelley’s ratio, magnesium ratio, Wilcox and USSL diagrams.  相似文献   

11.
To understand the impact of the influence of treated wastewater, a study was undertaken in the downstream side of Wadi Hanifa in the southern part of Riyadh City in Saudi Arabia. Chemical elements from 17 groundwater samples, 9 surface water samples (treated wastewater), and 14 soil samples were analyzed. Water facies analyses showed that both groundwater and surface water belong to the SO4-Cl class. However, the groundwater is characterized by high salinity (average value of 3547 mg/l), which may be result of the greater rock-water interaction and limited rainfall recharge. The NO3 values are also high in the groundwater samples (average value of 40 mg/l) and are mainly attributed to the agricultural practices in the study area. The surface water samples (treated wastewater from the plant) shows an average salinity value of 1232 mg/l and is better suited for irrigation purposes. Heavy elements analyzed in the soil samples show high concentrations of all the elements except Mn and Ni as compared to their background concentration. Enrichment factor and index of geoaccumulation calculated from the soil samples indicate that they are severely enriched with respect to Cd and Se. The spatial distribution maps were prepared based on kriging interpolation technique to estimate the concentrations of the analyzed elements at unknown locations. The treated wastewater in the study area is better suited for agricultural and domestic activities as compared to groundwater.  相似文献   

12.
13.
Life and the sustainable growth of socioeconomic sectors such as agriculture and industry depend on groundwater, particularly in arid and semi-arid regions where surface water resources are limited. The objectives of the current study are to characterize groundwater chemistry and assess its suitability for industrial usage in the Guanzhong Basin located in the semi-arid region of northwest China. To better understand the hydrogeochemistry in the study area, statistical analysis, ionic plots and Pearson's correlation analysis were conjunctively used. Finally, a novel industrial water quality index (IndWQI) model was developed in this paper to determine the overall industrial water quality based on scaling, corrosion, and foaming coefficients as well as some physicochemical parameters. The contribution of each parameter to the overall industrial water quality was determined using multivariate statistical analysis approaches. The findings reveal that dissolution of minerals such as calcite, dolomite, anhydrite and gypsum regulate the groundwater geochemistry in the study area. In addition, human activities influence the groundwater quality in the study area. According to the novel IndWQI approach, 78.95 % of the confined water samples and 74.51 % of the phreatic water samples have excellent or good quality, and can be safely used for industrial boilers. The geospatial analysis shows that the most contaminated groundwater samples are mainly located in northeast Xi'an and the northeast region of the Guanzhong Basin. The IndWQI model is trustworthy, as it can combine several water quality indices and give an instantaneous impression of the whole groundwater quality for industrial uses. It can serve as a benchmark for other areas across the world with a comparable climate.  相似文献   

14.
王彩云  曹建劲  戴冬乐 《地球科学》2018,43(5):1650-1662
采集内蒙古卡休他他矿区附近的地下水微粒进行相关分析,同时也采集远离矿区的井水微粒作为对照,利用高分辨率透射电镜对这些微粒进行单颗粒纳米微粒分析,研究表明:卡休他他矿床地下水中的异常金属微粒主要为含Fe、Cu、Zn微粒,含Zn、Cu微粒原子百分含量分别可达80.3%、22.7%,而背景区井水样品中无Ag、Cu微粒,且矿区地下水中与成矿相关的金属元素含量大大高于井水;含金属微粒与深部矿体成分(磁铁矿、黄铁矿、闪锌矿、黄铜矿等)具有很好的对应性,表明了矿区地下水含金属微粒来自于深部矿体,能携带深部矿体的信息,这为深部隐伏矿体的勘探提供了思路,也能为今后同类型的矿床勘探提供一定的参考.此外,本次研究还表明矿区附近的地下水可能受到了成矿微粒的影响,这可能也会影响到地下饮用水的品质,地下水含金属微粒研究方法也可用于检测地下饮用水的污染.关键字:卡休他他矿床;地下水;含金属微粒;单微粒分析;饮用水污染;环境地质.   相似文献   

15.
Groundwater is the main source of irrigation within south Al Madinah Al Munawarah region. It is also an important source of drinking water in many areas including Madinah city. The wells installed in the aquifer of the study area (south Madinah city) are not currently regulated by the local authorities although they are a key component of water supply. The aquifers in the study area range from unconfined to semi-confined and confined. The main aim of this study is to assess the groundwater in the region for drinking and agricultural uses. For this purpose, hydrochemical analyses of major, minor and trace constituents and nutrients were performed on 29 groundwater samples from the aquifer located about 20 km south of Madinah. The recharge rate of the aquifer of the study area was estimated to be 6.58 % of the annual precipitation using the chloride mass-balance method. Chloride was positively correlated with major ions, which suggests that agricultural activities have some effect on groundwater chemistry through leaching of readily soluble salts from the soil zone. Groundwater of the study area is characterized by dominance of Na over Ca. Chloride was found to be the most dominant anion and replaced by HCO3, thus reflecting geochemical evolution in the study area. The groundwater of the study area is not safe for drinking but can be safely used for salt-tolerant crops.  相似文献   

16.
17.
Assessment of groundwater suitability for drinking and agricultural purposes was carried out in the plain of upper Cheliff. The study area covers an area of 375 km2 and lies in a semiarid climate. Groundwater is the major source for domestic and agricultural activity in this area. Groundwater samples were collected from 19 wells during dry and wet periods in 2012, and they were analyzed for major cations and anions and compared with drinking and irrigation specification standards. The concentration of the majority of chemical constituents exceeds the standards of WHO as a result of various sources of pollution. It indicates the dominance of groundwater types: Ca-Mg-Cl, and Ca-Mg-HCO3. Suitability of groundwater for drinking was evaluated based on the water quality index; it shows more than 60% of samples have very poor quality for dry and wet periods, which means water is severely contaminated and unsuitable for drinking purpose. In terms of the irrigation usage, generally groundwater is suitable for both periods in the major part of the plain. The Mineralization processes in this area is determined by the lithology of the aquifer (exchange water-rock), by anthropogenic factors (discharges of urban sewage, use of fertilizers) and also by evaporation (semi-arid climate).  相似文献   

18.
乔冈  徐友宁  陈华清  张江华  刘瑞平 《地质通报》2015,34(11):2031-2036
以某金矿区浅层地下水为研究对象,通过分析112件浅层地下水样的Hg、Pb、Cd、Cr~(6+)、As、Cu、Zn、CN~-等重金属元素及氰化物的含量特征,初步查明了这8种元素在地下水中的赋存规律。在此基础上,分别利用单项、综合污染指数评价方法对浅层地下水环境质量进行了重金属及氰化物污染评价。结果表明,浅层地下水中除背景元素Cr~(6+)局部区域超标外,受矿业选冶活动影响,双桥河流域中下游段局部区域Hg、Pb、CN~-等元素超标,该结论对浅层地下水资源污染防治具有重要意义。  相似文献   

19.
This study describes the geochemistry of the topsoils from an arsenic (As)-affected area of the Datong Basin and identifies the possible sources and the enrichment mechanisms of As in groundwater. A total of 122 soil samples were collected from the study area. Analytical results indicate that soil As is higher than the average value of the Shanxi province topsoils. Fertilizer application and weathering of the bedrock both contributed to the presence of elements, including As, in the soil of the area. Furthermore, these elements may be strongly bound to Fe and Mn oxides/hydroxides. In addition, the depletion of K indicates that this element is readily leached into the groundwater rather than being retained in the soils. A groundwater area with high As levels corresponding spatially to soil samples with no As accumulation clearly shows the effects of irrigation or salt flushing on the soil compositions. Arsenic can be mobilized under reducing condition due to organic matter input or changes in redox conditions induced by irrigation or salt flushing and can be transported with vertically recharged water into shallow, unconfined aquifers, thus elevating the As concentration in groundwater.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号