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1.
Hydrochemical studies were carried out in parts of Oban Massif and Mamfe Embayment, Southeastern Nigeria to examine the contributions of barite mining activities on water quality. Pond and stream water samples were collected from six abandoned barite mines and adjoining streams areas during dry and wet seasons. These samples were analysed for physicochemical parameters using standard techniques. The results showed that the quality of water samples in the vicinity of barite mine sites was characterized by low pH, low mineralization, high suspended solids and deep colour. Sodium (Na+) and calcium (Ca2+) are the dominant cations and bicarbonate (HCO3 ?) and sulphate (SO4 2?) the dominant anions. The low concentration of dissolved silica, relatively high concentrations of Na+, HCO3 ? and SO4 2? suggest a combined influence of silicate, carbonate and weathering of mine spoils. The total dissolved solids, total suspended solids, electrical conductivity and major ions (except Na+ and K+) are higher for water draining barite mines from Cretaceous sediments, while Na+, K+, Ba2+ are higher in basement rock areas. Correlation and factor analyses suggest that the main components of the water samples are related to anthropogenic, geogenic, mineralization and environmental controls, while Gibbs diagram plots indicate weathering as the main process controlling the chemistry of water. Computed values of hardness and some irrigational parameters showed that the pond and stream water samples are generally soft and can be used for irrigation. Generally, the water quality satisfied the WHO (2008) and NIS (2007) standards for domestic, agriculture and industrial. However, there is the need to assess the impact of the pollution on the ecosystem and human health while remediation measures are being considered.  相似文献   

2.
Groundwater is a finite resource that is threatened by pollution all over the world. Shimabara City, Nagasaki, Japan, uses groundwater for its main water supply. During recent years, the city has experienced severe nitrate pollution in its groundwater. For better understanding of origin and impact of the pollution, chemical effects and surface–groundwater interactions need to be examined. For this purpose, we developed a methodology that builds on joint geochemical analyses and advanced statistical treatment. Water samples were collected at 42 sampling points in Shimabara including a part of Unzen City. Spatial distribution of water chemistry constituents was assessed by describing Stiff and Piper diagrams using major ions concentrations. The nitrate (NO3?+?NO2–N) concentration in 45% of water samples exceeded permissible Japanese drinking level of 10 mg L??1. Most of the samples showed Ca–HCO3 or Ca–(NO3?+?SO4) water types. Some samples were classified into characteristic water types such as Na–Cl, (Na?+?K)–HCO3, (Na?+?K)–(SO4?+?NO3), and Ca–Cl. Thus, results indicated salt water intrusion from the sea and anthropogenic pollution. At the upstream of Nishi River, although water chemistry was characterized as Ca–HCO3, ion concentrations were higher than those of other rivers. This is probably an effect of disinfection in livestock farming using slaked lime. Positive correlation between NO3? and SO42?, Mg2+, Ca2+, Na+, K+, and Cl? (r?=?0.32–0.64) is evidence that nitrate pollution sources are chemical fertilizers and livestock waste. Principal component analysis showed that chemistry of water samples can be explained by three main components (PCs). PC1 depicts general ion concentration. PC2 and PC3 share influence from chemical fertilizer and livestock waste. Cluster analyses grouped water samples into four main clusters. One of these is the general river chemistry mainly affected by PC1. The others reflect anthropogenic activities and are identified by the combination of the three PCs.  相似文献   

3.
This study was conducted to evaluate factors regulating groundwater quality in an area with agriculture as main use. Thirty groundwater samples have been collected from Razan area (Hamadan, Iran) for hydrochemical investigations to understand the sources of dissolved ions and assess the chemical quality of the groundwater. The chemical compositions of the groundwater are dominated by Na+, Ca2+, HCO3 −, Cl− and SO4 2−, which have been derived largely from natural chemical weathering of carbonate, gypsum and anthropogenic activities of fertilizer’s source. The production of SO4 2− has multiple origins, mainly from dissolution of sulphate minerals, oxidation of sulphide minerals and anthropogenic sources. The major anthropogenic components in the groundwater include Na+, Cl−, SO4 2− and NO3 −, with Cl− and NO3 − being the main contributors to groundwater pollution in Razan area.  相似文献   

4.
The hydrochemistry of Euphrates River in the study area which extended from Hit to Al-Saqlawia was studied in order to determine the physical, chemical, and biological properties in addition to the radiation level. Thirty-one stations along the Euphrates River were chosen, 17 of them represented the Euphrates River itself, whereas the other stations are considered as point pollution sources which all empty their load directly in the Euphrates River with an average total discharge of 32 m3/s. Twenty-eight samples of the Euphrates water of both high- and low-flow periods were analyzed for cations (Ca2+, Mg2+, Na+, and K+), anions (SO 4 = , Cl?, CO 3 = , HCO 3 ? , NO 3 ? , PO 4 ?3 ), H2S boron, dissolved oxygen, biological oxygen demand, bacteriological tests, radiation levels in addition to physical parameters such as hydrogen number (pH), total dissolved solid, electrical conductivity, total suspended solid, and temperature. This study showed that the cations and anions during periods of high and low flows are within acceptable limit with exceptional Cl?. Hydrochemical formula during the high flow was Na-Ca-Mg-Cl-SO4, then it changed into Na-Ca-Mg-HCO3-SO4-Cl during the low-flow period. The average output cations and anions at downstream (Saqlawiya area) was relatively higher than those of input at upstream (Hit area); this attributed to the natural and anthropogenic activities originated mainly from agricultural activity and population communities around the river. Radiation level for 212Pb, 214Pb, 40k, 220Ac, and 214Bi showed that the higher level of radiation is concentrated within sediment rather than in water, but the radiation in both is within acceptable limit.  相似文献   

5.
Hydogrochemical investigation of groundwater resources of Paragraph district has been carried out to assess the solute acquisition processes and water quality for domestic and irrigation uses. Fifty-five groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids, hardness, major anions (F?, Cl?, NO3, HCO3 ?, SO4 2?) and cations (Ca2+, Mg2+, Na+, K+). Study results reveal that groundwater of the area is alkaline in nature and HCO3 ?, Cl?, Mg2+, Na+ and Ca2+ are the major contributing ions to the dissolved solids. The hydrogeochemical data suggest that weathering of rock forming minerals along with secondary contributions from agricultural and anthropogenic sources are mainly controlling the groundwater composition of Pratapgarh district. Alkaline earth metals (Ca2++Mg2+) exceed alkalis (Na++K+) and weak acid (HCO3 ?) dominate over strong acids (Cl?+SO4 2?) in majority of the groundwater samples. Ca-Mg-HCO3 and Ca-Mg-Cl-HCO3 are the dominant hydrogeochemical facies in the groundwater of the area. The computed saturation indices demonstrate oversaturated condition with respect to dolomite and calcite and undersaturated with gypsum and fluorite. A comparison of groundwater quality parameters in relation to specified limits for drinking water shows that concentrations of TDS, F?, NO3 ? and total hardness exceed the desirable limits in many water samples. Quality assessment for irrigation uses reveal that the groundwater is good for irrigation. However, values of salinity, sodium adsorption ratio (SAR), residual sodium carbonate (RSC), %Na and Kelley index are exceeding the prescribed limit at some sites, demanding adequate drainage and water management plan for the area.  相似文献   

6.
Environmental geochemistry of Damodar River basin, east coast of India   总被引：1，自引：0，他引：1  
 Water and bed sediment samples collected from the Damodar River and its tributaries were analysed to study elemental chemistry and suspended load characteristics of the river basin. Na and Ca are the dominant cations and HCO3 is the dominant anion. The water chemistry of the Damodar River basin strongly reflects the dominance of continental weathering aided by atmospheric and anthropogenic activities in the catchment area. High concentrations of SO4 and PO4 at some sites indicate the mining and anthropogenic impact on water quality. The high concentration of dissolved silica, relatively high (Na+K)/TZ+ ratio (0.2–0.4) and low equivalent ratio of (Ca+Mg)/(Na+K) indicate that dissolved ions contribute significantly to the weathering of aluminosilicate minerals of crystalline rocks. The seasonal data show a minimum ionic concentration in the monsoon season, reflecting the influence of atmospheric precipitation on total dissolved solids contents. The suspended sediments show a positive correlation with discharge and both discharge and suspended load reach their maximum value during the monsoon season. Kaolinite is the mineral that is possibly in equilibrium with the water. This implies that the chemistry of the Damodar River water favours kaolinite formation. The concentration of heavy metals in the finer size fraction (<37 μ m) is significantly higher than the bulk composition. The geoaccumulation index values calculated for Fe, Mn, Zn, Ni and Cr are well below zero, suggesting that there is no pollution from these metals in Damodar River sediments. Received: 21 January 1998 · Accepted: 4 May 1998  相似文献   

7.
玉龙雪山地区大气降水中粉尘颗粒物特征研究   总被引：4，自引：1，他引：3  
以在玉龙雪山地区采集的大气降水样品为主要研究载体,分析了大气降水中粉尘颗粒物随时间的变化特征和影响大气降水中粉尘含量的潜在因素. 结果表明：大气降水中颗粒物浓度和典型粉尘特征化学离子含量的变化具有很好的一致性,且季风期末大气降水中的微粒含量显著升高,显示了明显的季节性变化特征. 丽江市和甘海子盆地大气降水中粉尘化学离子含量(SO42-,Mg2+,Ca2+,K+,NH4+,NO3-,粉尘浓度)之间具有较好的相关性,反映了这些离子共同的来源. 降水中pH值和电导率的变化很大程度上受到粉尘活动的影响,海盐气溶胶粒子对玉龙雪山地区大气降水中典型粉尘微粒(除Cl-和部分Na+之外)的沉降没有贡献. 此外,降水化学和微粒分析表明,丽江市区的大气环境不排除人为活动的影响.  相似文献   

8.
Located in the southeast of Tunisia, on the Mediterranean Sea, Jerba Island has a semiarid climate condition. The surface water scarcity has made groundwater the main source to supply the domestic, touristic, and agricultural water demand. Unconfined aquifer is a vulnerable costal aquifer system that undergoes several phenomena. This work aims at assessing the geochemical and bacteriological groundwater quality, defining groundwater pollution sources and promoting sustainable development and effective management of groundwater resources in Jerba Island. Data were collected after the wet season in 2014 from 79 wells. Electric conductivity, pH, TDS, and major and fecal tracers (total coliforms, thermotolerant coliforms, Escherichia coli, and Salmonella) were analyzed. Geochemical modeling including the relationships between geochemical tracers Na+ vs. Cl?, Ca2+ vs. Cl?, K+ vs. Cl?, representative ionic ratios (Br?/Cl?, Na+/Cl?, Mg2+/Ca2+), and statistical analysis were used to specify major process contributing to groundwater pollution and main factors controlling groundwater mineralization in the island. Groundwater varieties were hydrochemically classified into three types in terms of salinity values: group 1 (8.86%) to fresh water, group 2 (27.84%) to brackish water, and group 3 (63.29%) belongs to saline water. In addition, groundwater quality revealed high concentrations in chemical pollution tracers (Na+, Cl?, SO4 2?, and NO3 ?) and fecal tracers. Besides, most of the sampled wells were contaminated with nitrate (50.63%). Also, thermotolerant coliforms and E. coli were detected in all groundwater samples (96.2% of wells). Results indicated that the Jerba shallow aquifer was under serious threat from both natural and anthropogenic contamination. However, the wild discharge of domestic effluents, septic tanks, and sewage were the main origins of underground water contamination in Jerba Island. The reduction of fecal sources, through constructing normalized latrines is thus recommended.  相似文献   

9.
The study of groundwater hydrogeochemistry of a hard rock aquifer system in Thoothukudi district has resulted in a large geochemical data set. A total of 100 water samples representing various lithologies like Hornblende Biotite Gneiss, Alluvium Marine, alluvium Fluvial, Quartzite, Charnockite, Granite and Sandstone were collected for two different seasons and analyzed for major ions like Ca2+, Mg2+, Na+, K+, HCO3 ?, Cl?, SO4 2?, NO3 ?, PO4 ?, F? and H4SiO4. Statistical analysis of the data has been attempted to unravel the hidden relationship between ions. Correlation analyses and factor analyses were applied to classify the groundwater samples and to identify the geochemical processes controlling groundwater geochemistry. Factor analysis indicates that sea water intrusion followed by leaching of secondary salts, weathering and anthropogenic impacts are the dominant factors controlling hydrogeochemistry of groundwater in the study area. Factor score overlay indicate major active hydrogeochemical regimes are spread throughout the Eastern, Northwestern and Southeastern parts of the study area. The dominant ions controlling the groundwater chemistry irrespective of season are Cl?, Na+, Mg2+, Ca2+, SO4 2?, K+ and NO3 ?. An attempt has also been made to note the seasonal variation of the factor representations in the study area. This study also illustrates the usefulness of statistical analysis to improve the understanding of groundwater systems and estimates of the extent of salinity/salt water intrusion.  相似文献   

10.
Water soluble components of PM10 Chongqing, China   总被引：1，自引：0，他引：1  
The concentrations of water soluble ions (Na+, NH4 +, K+, Mg2+, Ca2+, NO3 -, Cl-, and SO 4 2- ) in PM10 samples collected on cellulose filters by a medium-volume cascade impactor were determined, which were obtained from three kinds of areas in Chongqing: industrial area (Jiulongpo district), commercial and residential area (Jiangbei district) and background area (Jinyun Mountain in the Beibei district). The results showed that except for the background site, the annual average values of PM10 are 23% – 61% higher than the national air quality standard (GradeII) (0.1 mg/m3), even that the value of the control site is still 20% higher than American standard (0.05 mg/m3). This implied that serious pollution of fine particles occurred in Chongqing. Nine kinds of soluble ions in water of PM10 were analyzed by ion chromatography (IC) and the annual average concentrations follow the order of [SO 4 2- ] > [NO3 -] > [Cl-] > [F-], and [Ca2+] > [NH4 +] > [K+] > [Na+] > [Mg2+]. Their values were different in these areas: the industrial area > the commercial and living area > the control area. As for NH4 +, K+, Ca2+, NO3 - and SO 4 2- , their seasonal average concentrations show a similar variation trend: the values in spring and fall were higher than those in summer and winter. The seasonal average concentrations of [Cl-], [F-], [Na+] and [Mg2+] are much lower than those of other ions. However, the concentrations of [Na+] changed more greatly in different seasons than those of the other three ions. Correlation coefficients showed that the three areas have been polluted by coal smoke and dust to different extents, while some local resources of pollution should be taken into consideration as well.  相似文献   

11.
South China is one of the regions severely suffering from acid rain in the world.However,few systematic studies of rural precipitation chemistry have been performed in comparison with the extensive studies on their urban counterparts of this region.In order to characterize the current acid rain status and identify its possible sources in the rural area of South China,we analyzed precipitation collected event by event from a rural forested watershed in southern Anhui Province between March 2007 and February 2010.The results showed that the concentrations of major ions within precipitation in the studied rural area were significantly lower than those reported for the urban areas of the same latitude in China.Nevertheless,the precipitation acidity(with an average pH value of 4.49) and the frequency of acid rain(95%) were considerably high.The relatively high ratio of(SO42+ NO 3)/(Ca2+ +NH4+) was the main cause of acid rain in this rural area,as SO 2 and NO x were the main precursors of acid rain,while Ca2+ and NH4+acted as the dominant neutralizers to the acidity.Source identification indicated that Ca2+ and Mg2+ mainly were derived from alkaline dust,SO42,NO 3 and NH4+originated mainly from anthropogenic sources such as industrial and agricultural activities,most Na +,Cl,K + and some of Mg2+ were derived from the sea.The results suggested that the major ions within precipitation in the rural area of South China were related to the meso-scale and long-range transport of particles and aerosols in the air.  相似文献   

12.
Heavy metals are constantly emitted into the environment and pose a major threat to human health, particularly in urban areas. The threat is linked to the presence of Cd, Cr, Cu, Ni, Pb, and Zn in street dust, which consists of mineral and organic particles originating from the soil, industrial emitters, motor vehicles, and fuel consumption. The study objective was to determine the level of street dust contamination with trace metals in Lublin and to indicate their potential sources of origin. The analyses were carried out with an energy-dispersive X-ray fluorescence spectrometer. The sampling sites (49) were located within the city streets characterised by varying intensity of motor traffic. The following mean content values and their variation (SD) were determined: Cd: 5.1?±?1.7 mg kg?1, Cr: 86.4?±?23.3 mg kg?1, Cu: 81.6?±?69.2 mg kg?1, Ni: 16.5?±?3.9 mg kg?1, Pb: 44.1?±?16.4 mg kg?1, and Zn: 241.1?±?94.6 mg kg?1. The level of pollution was assessed with several widely used geochemical indices (geoaccumulation index, enrichment factor, pollution index, index of ecological risk, and potential ecological risk index). For most of the indices, the mean (median) values are arranged in the following manner: Zn?>?Cu(or Cd)?>?Pb?>?Ni?>?Cr. In general, street dust in Lublin does not show pollution with Cr, Ni, and Pb. Igeo and EF indices show moderate levels for Cu, Cd, and Zn; their presence in street dust is linked with anthropogenic factors (motor traffic). A significant threat is posed by Cd, and more than half of the samples show considerable pollution with cadmium (median for the index of ecological risk: 151). The spatial pattern of indices and the results of statistical analyses (CA, PCA) indicate three groups of elements: (1) Cr and Ni: natural origin; (2) Pb: mixed origin; and (3) Cd, Cu, and Zn: anthropogenic origin (mainly motor vehicle traffic). Higher content values for metals of anthropogenic origin in street dust indicate that it is a source of pollution of soil and air in the city.  相似文献   

13.
Rainwater plays an important role in scavenging of aerosols and gases from atmosphere, and its chemistry helps to understand the relative contributions of atmospheric pollution sources. The present work is aimed to understand and explain the sources, seasonal patterns and the processes thereof affecting rainwater chemistry in an urban environment of Delhi, India. Rainwater samples (n = 111) collected throughout the year in New Delhi showed alkalinity in general. Eight rainwater samples, collected in late monsoon and winter season, had pH less than 5.6 indicating that Delhi continues to face the prospects of acid rain despite the introduction of compressed natural gas as the clean fuel in city transport. Organic acids could be the possible contributors of acidity in rainwater samples having the fractional acidity (FA) value of 0.174, which is greater than the annual average FA (0.011) and the (Ca2+ + Mg2+ + NH4 +)/(SO4 2? + NO3 ?) ration of more than one. Average acid neutralization factors of cations decrease in the order Ca2+ (1.01) > NH4 + (0.77) > Mg2+ (0.10). However, neutralization by Ca2+ dominates only in summer season as cation-rich dust is transported from the Great Indian Thar Desert to this region by strong summer S–SW winds, while NH4 + dominates in rainwater of other three sampling seasons. Identified dominant sources for soluble ions in rainwater are (1) non-silicate crustal source for carbonates and sulfates of Ca and Mg, (2) emissions from catalytic convertor-fitted vehicles and agriculture fields for NH3 and (3) mixed anthropogenic sources for SO4 2?, NO3 ? and Cl?. Rainwater chemistry showed significant seasonal variations. This could be due to the changes in relative proportions of natural and anthropogenic sources of soluble ions to rainwater. Dominance of anthropogenic sources over crustal sources can result in acidic rains, which can adversely affect the environment and human health in this region.  相似文献   

14.
The hydrogeochemical study of groundwater in Dumka and Jamtara districts has been carried out to assess the major ion chemistry, hydrogeochemical processes and groundwater quality for domestic and irrigation uses. Thirty groundwater samples were collected and analyzed for pH, electrical conductivity, total dissolved solids (TDS), total hardness, anions (F?, Cl?, NO3 ?, HCO3 ?, SO4 2?) and cations (Ca2+, Mg2+, Na+, K+). The analytical results show the faintly alkaline nature of water and dominance of Mg2+ and Ca2+ in cationic and HCO3 ? and Cl? in anionic abundance. The concentrations of alkaline earth metals (Ca2+?+?Mg2+) exceed the alkali metals (Na+?+?K+) and HCO3 ? dominates over SO4 2??+?Cl? concentrations in the majority of the groundwater samples. Ca?CMg?CHCO3 is the dominant hydrogeochemical facies in 60?% of the groundwater samples, while 33?% samples occur as a mixed chemical character of Ca?CMg?CCl hydrogeochemical facies. The water chemistry is largely controlled by rock weathering and ion exchange processes with secondary contribution from anthropogenic sources. The inter-elemental correlations and factor and cluster analysis of hydro-geochemical database suggest combined influence of carbonate and silicate weathering on solute acquisition processes. For quality assessment, analyzed parameter values were compared with Indian and WHO water quality standards. In majority of the samples, the analyzed parameters are well within the desirable limits and water is potable for drinking purposes. Total hardness and concentrations of TDS, Cl?, NO3 ? , Ca2+ and Mg2+ exceed the desirable limits at a few sites, however, except NO3 ? all these values were below the highest permissible limits. The calculated parameters such as sodium adsorption ratio, percent sodium (%Na) and residual sodium carbonate revealed excellent to good quality of groundwater for agricultural purposes, except at few sites where salinity and magnesium hazard (MH) values exceeds the prescribed limits and demands special management.  相似文献   

15.
The Kandy lake, situated in the heart of Sri Lanka's second largest city with a population of nearly 120,000, has been monitored to probe the extent of heavy metal pollution. Although the lake is a source of drinking water to the city, a large number of effluent canals drain into the lake carrying a continuous flow of industrial and domestic waste matter. A total of 66 surface water samples were analyzed for their Fe2+, total Fe, total V, SO 4 2− , Cd2+, and Pb2+ contents. Pb and Cd were found in high concentrations averaging 150 μg/l and 77 μg/l, respectively, and exhibit a marked positive correlation with each other (r=+0.94). Vehicular emissions and industrial waste matter contribute largely to the Pb and Cd contents of the lake, the anthropogenic influence outweighing the contributions made by geological materials. All field observations and laboratory experiments indicate a tendency of the Kandy Lake towards eutrophicity.  相似文献   

16.
Total suspended particulate samples (TSP) were collected and concentrations measured during seventeen months in the vicinity of a ceramic industrial area. A method of fractionating was applied to the samples in order to obtain two fractions corresponding to mineral particulate coming from dust emissions (Upper-F fraction) and to amorphous matter (carbon plus small amounts of S, Ca, Fe, etc) coming mainly from traffic and other combustion processes. Also for TSP samples several element concentrations were measured following two previous treatments: extraction of elements mainly associated with the soluble fraction of the samples (B, Fe, P, As, NO2–, NH4+, Cl–, F) and acid digestion for trace metals and elements mainly associated with the non-soluble fractions of the samples (Fe, As, Cd, Ni, Pb, Zn Ca). Seasonal differences and the influence of meteorological parameters (temperature, relative humidity, pressure and wind conditions) on the air pollution levels, particles as well as ions, were studied.Results show different seasonal and weekly evolution for mineral and amorphous carbonaceous particles because of the different origins in dust emissions or combustion processes respectively, and the different physical properties such as size grain. Of the ions analyzed Fe, Ca and Zn were clearly associated to mineral phases and consequently related to dust emissions, and NO2–, NH4+, P, Cl– were related to amorphous matter coming from combustion. Ni and Cd show lower levels than those reported as guideline values and the source is mainly related to the enrichment of these elements in clay materials. B and As content result in elevated concentrations, with the tendency to increase during cold months. The emission of these elements was associated with vaporization or volatilization during high temperature ceramic processes. The original gaseous state is influenced by temperature. In the winter the content for B and As is higher due to enhanced condensation of gas-phase boron onto particles, while in the summer the increase of air temperature results in elevated evaporation.  相似文献   

17.
The main aims of the present study are to identify the major factors affecting hydrogeochemistry of groundwater resources in the Marand plain, NW Iran and to evaluate the potential sources of major and trace elements using multivariate statistical analysis such as hierarchical clustering analysis (HCA) and factor analysis (FA). To achieve these goals, groundwater samples were collected in three sampling periods in September 2013, May 2014 and September 2014 and analyzed with regard to ions (e.g., Ca2+, Mg2+, Na+ and K+, HCO3 ?, SO4 2?, Cl?, F? and NO3 ?) and trace metals (e.g., Cr, Pb, Cd, Mn, Fe, Al and As). The piper diagrams show that the majority of samples belong to Na–Cl water type and are followed by Ca–HCO3 and mixed Ca–Na–HCO3. Cross-plots show that weathering and dissolution of different rocks and minerals, ion exchange, reverse ion exchange and anthropogenic activities, especially agricultural activities, influence the hydrogeochemistry of the study area. The results of the FA demonstrate that 6 factors with 81.7% of total variance are effective in the overall hydrogeochemistry, which are attributed to geogenic and anthropogenic impacts. The HCA categorizes the samples into two clusters. Samples of cluster C1, which appear to have higher values of some trace metals like Pb and As, are spatially located at the eastern and central parts of the plain, while samples of cluster C2, which express the salinization of the groundwater, are situated mainly westward with few local exceptions.  相似文献   

18.
A hydrogeochemical study of surface water of the West Bokaro coalfield has been undertaken to assess its quality and suitability for drinking, domestic and irrigation purposes. For this purpose, fourteen samples collected from rivers and ponds of the coalfield were analysed for pH, conductivity, total dissolved solids (TDS), major cations (Ca2+, Mg2+, Na+ and K+), major anions (HCO3-, F-, Cl-, SO42- and NO3-) and trace metals. The pH of the analysed water samples varied from 7.3 to 8.2, indicating slightly alkaline in nature. The electrical conductivity (EC) value varied from 93 μs cm-1 to 906 μs cm-1 while the TDS varied from 76 mg L-1 to 658 mg L-1. HCO3- and SO42- are the dominant anion and Ca2+ and Na+ the cation in the surface water. The concentration of alkaline earth metals (Ca2+ + Mg2+) exceed the alkali metals (Na+ + K+) and HCO3- dominates over SO42- + Cl- concentrations in the majority of the surface water samples. Ca2+ -Mg2+ -HCO3- and Ca2+ -Mg2+ -Cl- are the dominant hydrogeochemical facies in the surface water of the area. The water chemistry is mainly controlled by rock weathering with secondary contribution from anthropogenic sources. For quality assessment, analyzed water parameter values compared with Indian and WHO water quality standard. In majority of the samples, the analyzed parameters are well within the desirable limits and water is potable for drinking purposes. However, concentrations of TDS, TH, Ca2+, Mg2+ and Fe are exceeding the desirable limits in some water samples and needs treatment before its utilization. The calculated parameters such as sodium absorption ration, percent sodium, residual sodium carbonate, permeability index and magnesium hazard revealed good to permissible quality and suitable for irrigation purposes, however, higher salinity, permeability index and Mg-ratio restrict its suitability for irrigation at few sites.  相似文献   

19.
天山乌鲁木齐河源1号冰川融水径流水化学特征研究   总被引：3，自引：2，他引：1  
冯芳  冯起  刘贤德  李忠勤  刘蔚  金爽 《冰川冻土》2014,36(1):183-191
2006年和2007年的整个消融期内,在天山乌鲁木齐河源1号冰川末端水文控制点逐日定时采集融水径流样品,对样品的主要可溶离子、pH、电导率EC、总溶解固体TDS和悬移质颗粒物SPM进行了分析. 结果表明：天山乌鲁木齐河源1号冰川融水径流离子类型为Ca2+-HCO3--SO42-,呈弱碱性. 融水径流中TDS变化受日径流量调节显著,表现为消融初期和末期浓度较高,消融强烈时浓度较低;SPM以细颗粒物质为主,各粒度组分含量变化幅度较大,且质量浓度SSC年内变化与TDS呈相反的变化趋势. 融水径流中离子组成主要受岩石风化作用影响,离子摩尔比值和Piper图分析表明,控制冰川径流离子组成的主要过程是碳酸盐、黄铁矿和长石类矿物风化作用.  相似文献   

20.
为了研究祁连山大雪山地区大气PM2.5细粒子中可溶性无机离子组分的变化特征, 于2010年7月至2011年7月在祁连山冰川与生态环境综合观测站附近采集46个大气PM2.5的Telfon滤膜样品, 并应用离子色谱对可溶性离子进行了分析.结果显示: 所测样品的阴、 阳离子中, SO42-、 NO-3、 Ca2+和NH+4的质量浓度分别为1.54μg·m-3、 0.38μg·m-3、 0.73μg·m-3和0.22μg·m-3, 累计约占到水溶性离子总量的88%.可溶性离子浓度呈现出春夏季节明显高于秋冬季节的特征, 夏季的浓度最高, 其次是春季、 冬季和秋季. Cl-、 Ca2+、 Na+和Mg2+之间的相关性极高, SO42-和NO-3与大部分阳离子的相关性都很高, 说明大部分硫酸盐是来自于中亚沙尘源区的自然源, 而并非是通过人类活动造成的一次污染物通过二次反应过程得到的. NH+4仅与SO42-通过相关性检验说明, 该地区NH3主要中和了大气中硫酸并生成(NH4)2SO4.该地区的大气环境主要来源于自然源的影响, 但夏季风期间人为污染排放已经不可忽视, 这也得到HYSPLIT后向轨迹模式的计算验证.  相似文献   

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