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1.
The hydrochemical characteristics and quality of groundwater in Lokoja basement area have been evaluated based on different indices for assessing groundwater for drinking and irrigation purposes. Twenty groundwater samples were collected and analyzed for physicochemical parameters, major ions and heavy metals. The results revealed that the groundwater is slightly alkaline, with little variations in chemical composition. For example, electrical conductivity (EC) ranges from 242μS/cm to 1835μS/cm. The abundance of the major ions is in the order of Ca2+ >Na+>Mg2+>K+> Fe2+/3+ = HCO3 >Cl? >NO3 >SO4 >PO4. Based on the hydrochemical data, four hydrochemical facies were identified namely, Ca-Mg-HCO3, Na-K-HCO3, Na-K-Cl-SO4 and Ca-Mg-Cl-SO4 and these facies depict groundwater recharge zone, transition flow zone, deep flow zone and mixed water zone respectively. Groundwater from the area is unsuitable for drinking and domestic purposes as some of the ions and heavy metals of health concerns are well above the stipulated guideline values. Irrigation water quality indicators (salinity, Na % and Mg %), reveal that the groundwater is unsuitable for irrigation purposes. Interpreted statistical analysis reveals that the groundwater chemical compositions are controlled predominantly by weathering of litho units of the basement rocks and by drainage from domestic wastes.  相似文献   

2.
Groundwater is the most important natural resource used for drinking by many people around the world, especially in rural areas. In Tunisia, since the quantity and the quality of water available for different uses is variable from one place to another, groundwater quality in El Khairat deep aquifer was evaluated for its suitability for drinking purposes. To this end, an attempt has been made for the first time in order to determine spatial distribution of groundwater quality parameters and to identify places with the best quality for drinking within the study area based on: (1) an integrated analysis of physical?Cchemical parameters, (2) use of Geographical Information System, and (3) Water Quality Index (WQI) calculation. The physical?Cchemical results were compared with the World Health Organization (WHO) standards for drinking and public health, in order to have an overview of the present groundwater quality. According to the overall assessment of the basin, almost all the parameters analyzed are above the desirable limits of WHO. Using GIS contouring methods with Arcview 3.2a, spatial distribution maps of pH, TDS, EC, TH, Cl, HCO3, SO4, NO3, Ca, Mg, Na, and K have been created. The spatial analysis of groundwater quality patterns of the study area shows that the TDS value increases from north-west to south-east following the general trend of the Khairat aquifer flow direction. The spatial distribution map of TH shows that a majority of the groundwater samples falls in the very hard category. WQI was used to assess the suitability of groundwater from the study area for human consumption. From the WQI assessment, over 82% of the water samples fall within the ??Poor?? and ??Very poor?? categories, suggesting that groundwater from the south-eastern of the El Khairat deep aquifer is unsuitable for drinking purposes.  相似文献   

3.
The quality of groundwater was assessed by determining the physicochemical parameters (pH, EC, TDS and TH) and major ions concentration (HCO3, Cl, FSO4, Ca, Mg, Na and K) around Dindigul district, Tamil Nadu, India. The groundwater samples were collected from 59 bore wells covering the entire study area and analyzed using standard methods. The GIS mapping technique were adopted to highlight the spatial distribution pattern of physicochemical parameters and major ion concentration in the groundwater. Gibbs diagram reveals that the source of major ions is predominantly derived from rock–water interaction and evaporation dominance process. The salt combinations of the aquifers are dominated by CaHCO3, mixed CaMgCl, mixed CaMgHCO3 and CaCl facies type due to leaching and dissolution process of weathered rocks. The Canadian Council of Ministers of Environment Water Quality Index (CCMEWQI) suggests that most of the groundwater quality falls under good to marginal category. The statistical analysis indicates that the presence of major ions and physicochemical parameters are chiefly controlled by rock–water interaction and residence time of the groundwater. However, the major nutrient like nitrite in the groundwater probably comes from anthropogenic process. Based on the groundwater quality standards, majority of the samples are suitable for drinking purposes except few in the study area.  相似文献   

4.
The present study research investigation is aimed to assess the groundwater quality for the urban area in Khan Younis City, southern Gaza Strip, for multi-domestic purposes. The physicochemical analysis of the groundwater wells shows the major ions in the order of Na+ > Mg2+ > Ca2+ > B3+ > K+ and Cl? > HCO3 ? > SO4 2? > NO3 2? > F? > PO4 3?. Groundwater quality is classified as very hard-brackish water type. Ninety-five percent of the wells are classified as saline water type with high NO3 2? concentrations. Based on water quality index (WQI), the groundwater falls into one of three categories: fair water (10%), poor water (15%), very poor (45%), and worst (30%). The high WQI values are because of high Na+, Cl?, SO4 2?, and NO3 2? concentrations, while synthetic pollution index (SPI) values indicate that most about 80% of the wells are seriously polluted. Langelier Saturation Index (LSI) indicates that most of data are either slightly scale forming or corrosive water or slightly corrosive but non-scale forming, and 75% of the wells are suitable for construction purposes (have SO4 2? concentrations <300 mg/L). The groundwater reaches alarming situation, where almost chemically unsuitable for drinking purposes and the water to be used after proper treatment such as desalination.  相似文献   

5.
The assessment of groundwater quality and its environmental implications in the region of the abandoned Cunha Baixa uranium mine (Central Portugal) was carried out from 1995 to 2004. Shallow groundwater is the major water supply source for irrigation in the neighbourhood of Cunha Baixa village. Water samples from the mine site as well as from private wells were collected in order to identify the mining impact on water composition, the extent of contamination and the seasonal and temporal groundwater quality variations. Some of the sampled private wells contain waters having low pH (<4.5–5) and high values of EC, TDS, SO4, F, Ca, Mg, Al, Mn, Ni, U, Zn and 226Ra. The wells located through the ESE–WSE groundwater flow path (1 km down gradient of the mining site) display the most contaminated water. In the summer season, the levels of SO4, Al, Mn, and U were 50–120 times higher than those registered for uncontaminated waters and exceeded the quality limits for irrigation purposes, presenting soil degradation risks. Nevertheless, this study indicates that groundwater contamination suffered a small decrease from 1999 to 2004. The bioaccumulation of toxic metals such as Al, Mn, and U within the food chain may cause a serious health hazard to the Cunha Baixa village inhabitants.  相似文献   

6.
An integrated approach was used to evaluate the impact of flash flood recharge on groundwater quality and its suitability for drinking, irrigation, livestock and poultry uses in the Wadi Baysh Basin, Western Saudi Arabia. Analyses of 182 groundwater samples, collected from the study area before and after a flash flood (FF) event, show that the average concentrations of TDS, Mg, Na, Cl, NO3 and EC decreased significantly after the event. The major water types (mixed CaMgCl, NaCl and CaCl) indicate that the infiltration of surface water from FF recharge has a great influence on groundwater chemistry. Drinking water suitability maps, created using WHO standards, indicate that wells located in the upstream region are suitable for drinking despite their high TDS and total hardness (TH) values. Groundwater in the coastal region is unsuitable due to its high salinity, high TH and high concentrations of major ions. The suitability of groundwater for irrigational use was assessed using salinity, sodium adsorption ratio, bicarbonate hazard, residual sodium carbonate, Kelly’s ratio, magnesium hazard, sodium percentage and permeability index values, which indicated that groundwater in the study region is suitable for most soils and crops. After FF, groundwater quality is improved by dilution, especially in the downstream region. USSL classification shows that the majority of the water samples are in the C3S1, C4S2, and C3S2 classes and are therefore suitable for the irrigation of salt-tolerant crops. Irrigational suitability maps suggest that wells in the upstream region are suitable for irrigation, whereas wells located near to the coast are unfit for irrigation. This study implies that construction of check dams in the dry valleys (wadies) may improve the groundwater quality in the area.  相似文献   

7.
The Narava basin in Visakhapatnam district situated on the east coast is a productive agricultural area, and is also one of the fastest growing urban areas in India. The agricultural and urban-industrialization activities have a lot of impact on this coastal aquifer water quality. The hydrochemistry of the groundwater was analyzed in the basin area with reference to drinking and agricultural purposes. The area is underlain by Precambrian rocks like khondalites, charnockites and migmatites. The water samples were collected from shallow wells for the year 2008. Physical and chemical parameters of groundwater such as pH, total alkalinity (TA), electrical conductivity (EC), total dissolved solids (TDS), total hardness (TH), Ca2+, Mg2+, Na+, K+, HCO3 ?, Cl?, SO4 2?, NO3 ?, F? were determined. The analytical results revealed that the most of the groundwater found to be in polluted category. Geographical information system (GIS) was utilized to generate different spatial distribution maps of various chemical constituents in the study area. The analytical data were used to compute certain parameters such as salinity hazard, percent sodium (Na%), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), permeability index (PI), Kelley??s ratio (KR) and corrosivity ratio (CR) to determine the quality of water for agricultural purposes. The abundance of the major ions in the basin area was found to be in the following sequence: Na+?>?Ca2+?>?Mg2+?>?K+:Cl??>?HCO3 ??>?SO4 2??>?NO3 ??>?F?. According to Gibbs?? diagram most of the samples fall under rock dominance. As per Wilcox and USSL classification most of the groundwater samples are suitable for irrigation except few samples which are unsuitable due to the presence of high salinity and high sodium hazard. From the obtained data, it can be concluded that the water quality profile was good and useful for normal irrigation agriculture.  相似文献   

8.
Hydrogeochemical investigations were carried out around Fetzara Lake, Northeast Algeria, to assess the quality of groundwater for its suitability for drinking and irrigation purposes. The groundwater chemistry is mainly controlled by the water?Crock interactions, but also influenced by other processes such as evapotranspiration and ion exchange. Groundwater samples collected, during two periods (1993 and 2007) from wells in the area were analyzed for pH, EC, TDS, Ca2+, Mg2+, Na+, K+, CO 3 2? , HCO 3 ? , Cl?, SO 4 2? , and NO 3 ? . The chemical relationships in Piper??s diagram and Gibbs??s diagram suggest that groundwaters mainly belong to noncarbonate alkali type and Cl? group and are controlled by evaporation dominance, respectively, due to the sluggish drainage conditions, greater water?Crock interaction, and anthropogenic activities. A comparison of the groundwater quality in relation to drinking water quality standards proves that most of the water samples are not suitable for drinking. US Salinity Laboratory??s and Wilcox??s diagrams and %Na+ used for evaluating the water quality for irrigation suggest that the majority of the groundwater samples are not good for irrigation.  相似文献   

9.
Fifty groundwater samples were collected from Al-Hasa to analyze the pH, electrical conductivity (EC, dS m?1), total dissolved solids (TDS), major anions (HCO3?, CO32?, Cl?, SO42?, and NO3?), major cations (Ca2+, Mg2+, Na+, and K+), and total hardness. The analyzed data plotted in the Piper, Gibbs, and Durov diagrams, and water quality index (WQI) were calculated to evaluate the groundwater geochemistry and its water quality. The results reveal that most of the investigated samples are Ca2+, Mg2+, SO42?, Cl? and Na+, and HCO3? water types using the Piper diagram. Na+?>?Ca2+?>?Mg2+ are the dominant cations, while Cl??>?HCO3??>?SO42??>?CO32? are the dominant anions. Sodium adsorption ratio (SAR) values varied from 0.79 to 10; however, the Kelly ratio (KR) ranged between 0.1 and 2.2. The permeability index (PI) showed that well water is suitable for irrigation purposes with 75% or more of maximum permeability. The US salinity diagram revealed that the water quality classes of studied waters were CIII-SI, CIII-SII, and CIV-SII, representing height hazards of salinity and medium- to low-sodium hazard. The water quality index (WQI) results indicated that total dissolved solids are out of the drinking water standard limits in Saudi Arabia. The WQI revealed that 38% of the studied wells were considered as poor water (class III), 52% are found as very poor water class (IV), and 10% are unsuitable water for drinking class (V).  相似文献   

10.
Groundwater is of a paramount importance in arid areas, as it represents the main water resource to satisfy the different needs of the various sectors. Nevertheless, coastal aquifers are generally subjected to seawater intrusion and groundwater quality degradation. In this study, the groundwater quality of the coastal Jeffara aquifer (southeastern Tunisia) is evaluated to check its suitability for irrigation purposes. A total of 74 groundwater samples were collected and analyzed for various physical and chemical parameters, such as, electrical conductivity, pH, dissolved solids (TDS), Na, K, Ca, Mg, Cl, HCO3, and SO4. Sodium adsorption ratio, magnesium adsorption ratio, Sodium percentage, and permeability index were calculated based on the analytical results. The analytical results obtained show a strong mineralization of the water in the studied aquifer. TDS concentrations range from 3.40 to 18.84 g?L?1. Groundwater salinity was shown to be mainly controlled by sodium and chloride. The dominant hydrochemical facieses are Na–Cl–Ca–SO4, mainly as a result of mineral dissolution (halite and gypsum), infiltration of saline surface water, and seawater intrusion. Assessment of the groundwater quality of the different samples by various methods indicated that only 7% of the water, in the northwest of the study area, is considered suitable for irrigation purposes while 93% are characterized by fair to poor quality, and are therefore just suitable or unsuitable for irrigation purposes.  相似文献   

11.
Hydrogeochemical investigations were carried out in the south-eastern part of the Ranga Reddy district, Hyderabad, India, to assess the quality of groundwater for its suitability for domestic and irrigation purposes. The area falls under a semi-arid type of climate and consists of granites and pegmatites of igneous origin of Archaean age. Forty-five representative groundwater samples were collected from bore wells to monitor the water chemistry of various ions, comprising Ca +2, Mg +2, Na +, K +, CO 3 -2, HCO 3 -, SO 4 -2, NO 3 -, Cl - and F -. The results showed that the concentrations of these ions are above the permissible limits for drinking and irrigation purposes. The pollution with respect to NO 3 -, Cl -, and F - is mainly attributed to the extensive use of fertilizers and large-scale discharge of municipal wastes into the open drainage system of the area.  相似文献   

12.
Hydrogeochemical investigations are carried out in the different blocks of Burdwan district, West Bengal, India in order to assess its suitability for drinking as well as irrigation water purpose. Altogether 49 representative groundwater samples are collected from bore wells and the water chemistry of various ions viz. Ca2+, Mg2+, Na+, K+, CO32−, HCO3−, Cl−, SO42− and NO3− are carried out. The chemical relationships in Piper and Gibbs diagram suggest that the groundwater mainly belongs to alkali type and Cl− group and are controlled by rock dominance. A comparison of groundwater quality in relation to drinking water quality standards proves that most of the water samples are suitable for drinking water purpose whereas groundwater in some areas of the district has high salinity and high sodium adsorption ratio (SAR), indicating unsuitability for irrigation water and needs adequate drainage.  相似文献   

13.
Assessment of groundwater quality in and around Vedaraniyam,South India   总被引：1，自引：1，他引：0  
Groundwater from 47 wells were analyzed on the basis of hydrochemical parameters like pH, electric conductivity, total dissolved solids, Ca2+, Mg2+, Na+, K+, Cl?, CO3 2?, HCO3 ?, NO3 ?, PO4 3? and F? in the Cauvery delta of Vedaraniyam coast. Further, water quality index (WQI), sodium percentage (Na %), sodium absorption ratio, residual sodium carbonate, permeability index and Kelley’s ratio were evaluated to understand the suitability of water for drinking and irrigation purposes. The result shows significant difference in the quality of water along the coastal stretch. The order of dominance of major ions is as follows: Na+ ≥ Mg2+ ≥ Ca2+ ≥ K+ and Cl? ≥ HCO3 ? ≥ CO3 2? ≥ PO4 3? ≥ F?. Na/Cl, Cl/HCO3 ratio and Revelle index confirmed that 60–70 % of the samples were affected by saline water intrusion. WQI showed that 36 % of the samples were good for drinking and the remaining were poor and unsuitable for drinking purpose. The degradation of groundwater quality was found to be mainly due to over-exploitation, brackish aquaculture practice, fertilizer input from agriculture and also due to domestic sewage.  相似文献   

14.
Groundwater in Farashband plain, Southern Iran, is the main source of water for domestic and agricultural uses. This study was carried out to assess the overall water quality and identify major variables affecting the groundwater quality in Farashband plain. The hydrochemical study was undertaken by randomly collecting 84 groundwater samples from observation wells located in 13 different stations covering the entire plain in order to assess the quality of the groundwater through analysis of major ions. The water samples were analyzed for various physicochemical attributes. Groundwater is slightly alkaline and largely varies in chemical composition; e.g., electrical conductivity (EC) ranges from 2314 to 12,678 μS/cm. All the samples have total dissolved solid values above the desirable limit and belong to a very hard type. The abundance of the major ions is as follows: Na+ > Ca2+ > Ma2+ > K+ and Cl? > SO4 2– > HCO3 ?. Interpretation of analytical data shows three major hydrochemical facies (Ca–Cl, Na–Cl, and mixed Ca–Mg–Cl) in the study area. Salinity, total dissolved solids, total hardness, and sodium percentage (Na%) indicate that most of the groundwater samples are not suitable for irrigation as well as for domestic purposes and far from drinking water standard. A comparison of groundwater quality in relation to drinking water standards showed that most of the water samples are not suitable for drinking purposes. Based on the US salinity diagram, most of samples belong to high salinity and low to very high sodium type.  相似文献   

15.
This paper discusses the hydrochemistry variation and its quality status in Langat River, based on the chemistry of major ions, metal concentrations and suitability for drinking purposes. Water samples were collected from 30 different stations to assess their hydrochemical characteristics. The physico-chemical parameters selected were temperature, electrical conductivity, total dissolved solids (TDS), salinity, dissolved oxygen , pH, redox potential, HCO3, Cl, SO4, NO3, Ca, Na, K, Mg, 27Al, 138Ba, 9Be, 111Cd, 59Co, 63Cu, 52Cr, 57Fe, 55Mn, 60Ni, 208Pb, 80Se and 66Zn to investigate the variation of the constituents in the river water. Most of the parameters comply with the Drinking Water Quality Standard of the World Health Organization and the Malaysian National Standard for Drinking Water Quality by the Malaysia Ministry of Health except for EC, TDS, Cl, HCO3, SO4, Na, Mg, Al, Fe and Se. The results show that the Langat River is unsuitable for drinking purposes directly without treatment.  相似文献   

16.
In order to study the major ion chemistry and controls of groundwater, 65 groundwater samples were collected and their major ions measured from wells within Lhasa River Basin. Groundwater has the characteristics of slightly alkaline and moderate total dissolved solid (TDS). TDS concentration ranged from 122.0 to 489.9 mg/L with a median value of 271.2 mg/L. Almost all the groundwater samples suited for drinking and irrigation. The major cations of groundwater are Ca2+ and Mg2+, accounting for 59.6 and 31.3% of the cations, respectively. Meanwhile, HCO3? and SO42? constituted about 56.7 and 36.9% of the anions, respectively, in Lhasa River Basin. The hydrochemical type of groundwater is HCO3-SO4-Ca-Mg. The chemical composition of groundwater samples located in the middle of Gibbs model, which indicates that the major chemical process of groundwater is controlled by rock weathering. Carbonate weathering was the dominant hydro-geochemical process controlling the concentration of major ions in groundwater within Lhasa River Basin, but silicate weathering also plays an important role.  相似文献   

17.
In India, the quantity and quality of water available for irrigation is variable from place to place. Assessment of water quality has been carried out to determine the sources of dissolved ions in groundwater. Quality of groundwater in a 398 km2 Peddavanka watershed of a semi-arid region of south India is evaluated for its suitability for drinking and irrigation purposes. The middle Proterozoic Cuddapah Supergroup and Kurnool Group of rocks underlie most of the watershed. The main lithologic units consist chiefly of quartzite, limestone, and shale. Seventy-six water samples were collected from open-wells and bore-holes. Water samples were collected representative of the post-monsoon (winter) and pre-monsoon (summer). The quality assessment is made through the estimation of Ca2+, Mg2+, Na+, K+, Cl−, SO42−, CO32−, HCO3−, total hardness as CaCO3, TDS, EC, and pH. Based on these analyses, parameters like sodium adsorption ratio, % sodium, residual sodium carbonate, non-carbonate hardness, potential salinity, Kelley’s ratio, magnesium ratio, index of base exchange and permeability index were calculated. According to Gibbs‘ ratio samples in both seasons fall in the rock dominance field. The overall quality of waters in the study area in post-monsoon season is high for all constituents ruling out pollution from extraneous sources.  相似文献   

18.
Hydrogeochemical characteristics of groundwater and its suitability for domestic, irrigation, and industrial purposes were evaluated in Nanded Tehsil. A total of 50 representative groundwater samples were collected from dug/bore wells during post monsoon season 2012 and analyzed for major cations and anions. The order of dominance of cation and anions were Na > Ca > Mg > K and HCO3 > Cl > CO3 > SO4 > NO3, respectively. The rock weathering and evaporation processes are dominant in controlling the groundwater quality in the study area. Electrical conductivity (EC) and total dissolved solid (TDS) show high positive correlation with total Hardness (TH), Ca, Na, and Cl. As per the WHO and BIS standards for domestic water purposes, TDS, TH, Ca, Mg, Na, and Cl exceed the safe limits in 16, 22, 6, 18, 12, and 15 %, respectively; therefore, majority of samples show that the groundwater is suitable for drinking. The spatial distribution maps of physicochemical parameters were prepared in ArcGIS. The suitability of groundwater for agriculture purpose was evaluated from EC, TDS, sodium adsorption ratio (SAR), residual sodium carbonate (RSC), and %Na which ranges from excellent to unsuitable, so majority of the groundwater samples are suitable for irrigation. The U.S. Salinity Laboratory (USSL) diagram shows that most of the groundwater samples are characterized as in high salinity-low sodium hazard type water (C3-S1). All the groundwater samples are suitable for industrial use except sample numbers 44 and 48. Thus, most of the groundwater samples from this study confirm the beneficial use of aquifers in the area for domestic, agricultural, and irrigation purposes. However, sample numbers 44 and 48 identify the two aquifers in the study area which are problematic and need particular remedial measures if they are to have beneficial use.  相似文献   

19.
Groundwater is critical for the sustainable development of the Loess Plateau, while groundwater quality is generally poor in this area due to natural factors and anthropogenic pollution. This study was carried out to investigate the suitability of groundwater for domestic and agricultural purposes in Yan’an City on the Chinese Loess Plateau and to assess its implications to sustainable groundwater management on the plateau. The index levels were compared with the threshold values established by the national and the WHO drinking water guidelines, and the suitability of groundwater for irrigation purposes was assessed using multiple agricultural water quality indicators. An entropy-weighted Technique for Order Preference by Similarity to an Ideal Solution (entropy-weighted TOPSIS) was adopted for overall groundwater quality assessment. The results indicate that the study area is characterized by saline, hard, and slightly alkaline groundwater, mainly of the HCO3–Ca·Mg type, accompanied by some minor SO4·Cl–Ca·Mg type. The dissolution of carbonates and gypsum and the leaching of soluble salts are important natural processes influencing the groundwater ion chemistry. The parameters TH, TDS, and SO42? are major indices, while Fe, Mn, F?, and NH4+ are minor contaminants affecting groundwater quality. The overall groundwater quality is generally acceptable for irrigation, and most of the water is suitable for drinking. Rainwater harvesting, water quality improvement programs, regular water quality monitoring, and multidisciplinary water research programs are suggested as measures for sustainable groundwater management on the Loess Plateau.  相似文献   

20.
Groundwater samples from three different states of southeastern Nigeria were analyzed for a range of physicochemical parameters and heavy metal constituents in order to determine their potability as drinking water sources. The results indicate that the physicochemical parameters (pH, temperature, TDS, TH, electrical conductivity, Cl?, NO3 ? and SO4 2?) tested for have most of their values fall within the permissible limits given by the Nigerian and World Health Organization standards for drinking water quality. The results also reveal that apart from Cu and Pb the rest of the tested heavy metals (As, Zn, Ni, total Fe, Cd and Mn) recorded values that are significantly above the maximum permissible limits for drinking water purposes and therefore have the potential to cause health impacts for long-term potable use. On the basis of principal component analysis, the sources of the measured chemical constituents are likely to be predominantly geogenic (weathering of soluble minerals in the formations) and partly anthropogenic (industrial effluent, agricultural practices and mining activities). Single-factor ANOVA tests indicated insignificant differences in the datasets within/between states or geological units. Caution or adequate treatment is generally required when utilizing the groundwater from the area for drinking purpose due to the elevated metal concentrations and rating as poor to unsuitable water quality.  相似文献   

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