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 765 毫秒
1.
Geochemical processes that take place in the aquifer have played a major role in spatial and temporal variations of groundwater quality. This study was carried out with an objective of identifying the hydrogeochemical processes that controls the groundwater quality in a weathered hard rock aquifer in a part of Nalgonda district, Andhra Pradesh, India. Groundwater samples were collected from 45 wells once every 2 months from March 2008 to September 2009. Chemical parameters of groundwater such as groundwater level, EC and pH were measured insitu. The major ion concentrations such as Ca2+, Mg2+, Na+, K+, Cl−, and SO4 2− were analyzed using ion chromatograph. CO3 − and HCO3 − concentration was determined by acid–base titration. The abundance of major cation concentration in groundwater is as Na+ > Ca2+ > Mg2+ > K+ while that of anions is HCO3 − > SO4 2− > Cl− > CO3 −. Ca–HCO3, Na–Cl, Ca–Na–HCO3 and Ca–Mg–Cl are the dominant groundwater types in this area. Relation between temporal variation in groundwater level and saturation index of minerals reveals the evaporation process. The ion-exchange process controls the concentration of ions such as calcium, magnesium and sodium. The ionic ratio of Ca/Mg explains the contribution of calcite and dolomite to groundwater. In general, the geochemical processes and temporal variation of groundwater in this area are influenced by evaporation processes, ion exchange and dissolution of minerals.  相似文献   

2.
Systematic hydrogeochemical survey has been carried out for understanding the sources of dissolved ions in the groundwaters of the area occupied by Sarada river basin, Visakhapatnam district, Andhra Pradesh, India. Khondalites, charnockites and granite gneisses and calc-granulites of Precambrians and alluvial deposits of Quaternaries underlie the study area. Groundwaters are both fresh and brackish; the latter waters being a dominant. Most groundwaters are characterized by Na+:HCO3− facies due to chemical weathering of the rocks. Enrichment of Na+, K+, Cl−, SO42−, NO3− and F− in some groundwater samples is caused by seawater intrusion, locally accompanied by ion-exchange, and anthropogenic activities, resulting in an increase of brackish in the groundwaters. Based on the results of this hydrogeochemical study, suitable management measures are recommended to solve the water quality problems.  相似文献   

3.
The area in Guntur district, Andhra Pradesh, India, is selected to discuss the impact of seasonal variation of groundwater quality on irrigation and human health, where the agriculture is the main livelihood of rural people and the groundwater is the main source for irrigation and drinking. Granite gneisses associated with schists and charnockites of the Precambrian Eastern Ghats underlie the area. Groundwater samples collected seasonally, pre- and post-monsoons, during three years from forty wells in the area were analyzed for pH, EC, TDS, TA, TH, Ca2+, Mg2+, Na+, K+, CO32−, HCO3−, Cl−, SO42−, NO3−and F−. The chemical relationships in Piper’s diagram, Chebotarev’s genetic classification and Gibbs’s diagram suggest that the groundwaters mainly belong to non-carbonate alkali type and Cl− group, and are controlled by evaporation-dominance, respectively, due to the influence of semi-arid climate, gentle slope, sluggish drainage conditions, greater water–rock 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, especially in post-monsoon period. 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 in post-monsoon compared to that in pre-monsoon. These conditions are caused due to leaching of salts from the overlying materials by infiltrating recharge waters. A management plan is suggested for sustainable development of the area.  相似文献   

4.
Hydrochemical investigations were carried out in Damagh area, Hamadan, western Iran, to assess chemical composition of groundwater. Forty representative groundwater samples were collected from different wells to monitor the water chemistry of various ions. Chemical analysis of the groundwater showed that the mean concentration of the cations is in the order Na+ > Ca2+ > Mg2+ > K+, while that for anions was HCO3− > Cl− > SO42 − > NO3−. All of the investigated groundwaters present two different chemical facies (Ca–HCO3 and Na–HCO3) which is in relation with their interaction with the geological formations of the basin, cation exchange between groundwater and clay minerals and anthropogenic activities. The principal component analysis (PCA) performed on groundwater identified three principal components controlling their variability in groundwater. Electrical conductivity, Mg2+, Na+, SO42−, and Cl− content were associated in the same component (PC1) (salinity), determined principally by anthropogenic activities. The pH, CO32 −, HCO3−, and Ca2+ (PC2) content were related to the geogenic factor. Finally, the NO3−, Cl− and K+ (PC3) were controlled by anthropogenic activity as a consequence of inorganic fertilizers.  相似文献   

5.
The effects of multiple industrial-pollutant sources on the groundwater system were evaluated in the Industrial Development Areas (IDAs) of Medak district, Andhra Pradesh (AP), India. The quality of groundwater in the region has been affected negatively due to the discharge of effluents on open land and into ponds, tanks, and streams. Water samples from surface-water bodies, dug wells,and bore wells were analyzed for their major ion concentrations. The high values of electrical conductivity (EC) and concentrations of Na+, Ca2+, Cl–, and HCO3 – indicate the impact of industrial effluents. Based on the hydrochemistry, the groundwater is classified into various types, such as sodium-chloride, sodium-bicarbonate, calcium-chloride, and magnesium-chloride, and its suitability for drinking and irrigation has been assessed. The present studies made it possible to demarcate areas of contaminated groundwater and those prone to contamination in the near future. Water in the area has deteriorated all along Nakka Vagu up to a maximum distance of 500–700 m from the eastern bank. The groundwater quality in and around Patancheru (to a depth of 30 m) has become hazardous. Some possible remedial measures are suggested. Electronic Publication  相似文献   

6.
An integrated study has been carried out to elucidate the distribution and occurrence of arsenic in selected groundwater samples in the area of Sherajdikhan, Bangladesh. Arsenic and other parameters (T, pH, EC, Na+, K+, Ca2+, Mg2+, Cl−, NO3 −, SO4 2−, HCO3 −, PO4 3−, Fe, Mn and DOC) have been measured in groundwater samples collected from shallow/deep tube wells at different depths. Hydrogeochemical data suggest that the groundwaters are generally Ca–Mg–HCO3 and Mg–Ca–HCO3 types with bicarbonate (HCO3 −) as the dominant anion, though the other type of water has also been observed. Dissolved arsenic in groundwater ranged from 0.006 to 0.461 mg/l, with 69% groundwater samples exceeded the Bangladesh limit for safe drinking water (0.05 mg/l). Correlation and principal component analysis have been performed to find out possible relationships among the examined parameters in groundwater. Low concentrations of NO3 − and SO4 2−, and high concentrations of DOC, HCO3 − and PO4 3− indicate the reducing condition of subsurface aquifer where sediments are deposited with abundant organic matter. Distinct relationship of As with Fe and Mn, and strong correlation with DOC suggests that the biodegradation of organic matter along with reductive dissolution of Fe–Mn oxyhydroxides has being considered the dominant process to release As in the aquifers studied herein.  相似文献   

7.
Many cities around the world are developed at alluvial fans. With economic and industrial development and increase in population, quality and quantity of groundwater are often damaged by over-exploitation in these areas. In order to realistically assess these groundwater resources and their sustainability, it is vital to understand the recharge sources and hydrogeochemical evolution of groundwater in alluvial fans. In March 2006, groundwater and surface water were sampled for major element analysis and stable isotope (oxygen-18 and deuterium) compositions in Xinxiang, which is located at a complex alluvial fan system composed of a mountainous area, Taihang Mt. alluvial fan and Yellow River alluvial fan. In the Taihang mountainous area, the groundwater was recharged by precipitation and was characterized by Ca–HCO3 type water with depleted δ18O and δD (mean value of −8.8‰ δ18O). Along the flow path from the mountainous area to Taihang Mt. alluvial fan, the groundwater became geochemically complex (Ca–Na–Mg–HCO3–Cl–SO4 type), and heavier δ18O and δD were observed (around −8‰ δ18O). Before the surface water with mean δ18O of −8.7‰ recharged to groundwater, it underwent isotopic enrichment in Taihang Mt. alluvial fan. Chemical mixture and ion exchange are expected to be responsible for the chemical evolution of groundwater in Yellow River alluvial fan. Transferred water from the Yellow River is the main source of the groundwater in the Yellow River alluvial fan in the south of the study area, and stable isotopic compositions of the groundwater (mean value of −8.8‰ δ18O) were similar to those of transferred water (−8.9‰), increasing from the southern boundary of the study area to the distal end of the fan. The groundwater underwent chemical evolution from Ca–HCO3, Na–HCO3, to Na–SO4. A conceptual model, integrating stiff diagrams, is used to describe the spatial variation of recharge sources, chemical evolution, and groundwater flow paths in the complex alluvial fan aquifer system.  相似文献   

8.
The Zhangye Basin, located in arid northwest China, is an important agricultural and industrial center. In recent years rapid development has created an increased demand for water, which is increasingly being fulfilled by groundwater abstraction. Detailed knowledge of the geochemical evolution of groundwater and water quality can enhance understanding of the hydrochemical system, promoting sustainable development and effective management of groundwater resources. To this end, a hydrochemical investigation was conducted in the Zhangye Basin. Types of shallow groundwater in the Zhangye Basin were found to be HCO3 −, HCO3 −–SO4 2−, SO4 2−–HCO3 −, SO4 2−–Cl−, Cl−–SO4 2− and Cl− . The deep aquifer groundwater type was found to be HCO3−–SO42− throughout the entire area. Ionic ratio and saturation index calculations suggest that silicate rock weathering and evaporation deposition are the main processes that determine the ionic composition in the study area. The suitability of the groundwater for irrigation was assessed based on the US Salinity Laboratory salinity classification and the Wilcox diagram. In the study area, the compositions of the stable isotopes δ18O and δD in groundwater samples were found to range from −4.00 to −9.28‰ and from −34.0 to −65.0‰, respectively. These values indicate that precipitation is the main recharge source for the groundwater system; some local values indicate high levels of evaporation. Tritium analysis was used to estimate the ages of the different groundwaters; the tritium values of the groundwater samples varied from 3.13 to 36.62 TU. The age of the groundwater at depths of less than 30 m is about 5–10 years. The age of the groundwater at depths of 30–50 m is about 10–23 years. The age of the groundwater at depths of 50–100 m is about 12–29 years. For groundwater samples at depths of greater than 100 m, the renewal time is about 40 years.  相似文献   

9.
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   

10.
This study applied a comprehensive quantitative approach including statistical, principal component and gray relation analyses to assess the groundwater chemistry based on monitored data from 840 samples collected from the lower reaches of Tarim River from 2000 to 2009. The main findings were: (1) there were six types of groundwater chemistry in the lower reaches of Tarim River where Cl·SO4–Na·Mg was the dominant type accounting for 73.57% in all samples. There were linear relationships among chemical parameters, where TDS had significant multiple correlations with Na+, K+, Mg2+, Ca2+ and Cl−, respectively. (2) Three principal components (PC1, PC2 and PC3) were extracted. They included comprehensive measurements for salinization, alkalinity and pH, respectively. Most parameters showed decreasing trends during the period of 2000–2009, as well as the scores on PC1, because the concentrations of various chemical substances were diluted due to the uplift of the groundwater table in the lower reaches and the implementation of the ecological water delivery project in 2000. (3) HCO3 − was the most sensitive chemical parameter affected by the groundwater table followed by TA, Mg2+, TH, SO42−, K+, TDS and TS. PC2 was the most sensitive principal component to the change of the groundwater table followed by PC1 and PC3.  相似文献   

11.
Nitrate (NO3 −) is major pollutant in groundwater worldwide. Karst aquifers are particularly vulnerable to nitrate contamination from anthropogenic sources due to the rapid movement of water in their conduit networks. In this study, the isotopic compositions (δ15N–NO3 −, δ15N–NH4 +) and chemical compositions(e.g., NO3 −, NH4 +, NO2 −, K+) were measured in groundwater in the Zunyi area of Southwest China during summer and winter to identify the primary sources of contamination and characterize the processes affecting nitrate in the groundwater. It was found that nitrate was the dominant species of nitrogen in most of the water samples. In addition, the δ15N–NO3 − values of water samples collected in summer were lower than those collected in winter, suggesting that the groundwater received a significant contribution of NO3 − from agricultural fertilizer during the summer. Furthermore, the spatial variation in the concentration of nitrate and the δ15N–NO3 − value indicated that some of the urban groundwater was contaminated with pollution from point sources. In addition, the distribution of δ15N–NO3 − values and the relationship between ions in the groundwater indicated that synthetic and organic fertilizers (cattle manure) were the two primary sources of nitrate in the study area, except in a few cases where the water had been contaminated by urban anthropogenic inputs. Finally, the temporal and spatial variation of the water chemistry and isotopic data indicated that denitrification has no significant effect on the nitrogen isotopic values in Zunyi groundwater.  相似文献   

12.
The Kali-Hindon is a watershed in the most productive central Ganga plain of India. The whole area is a fertile track with sugarcane being the principal crop. Systematic sampling was carried out to assess the source of dissolved ions, impact of sugar factories and the quality of groundwater. Thirty-six samples were collected covering an area of 395 km2. The quality of groundwater is suitable for irrigational purposes but is rich in SO4 which is not best for human consumption. Graphical treatment of major ion chemistry helps identify six chemical types of groundwater. All possible species such as Na–Cl, K–Cl, Na–HCO3, Na–SO4, Ca–HCO3, Mg–HCO3, Ca–SO4 and Mg–SO4 are likely to occur in the groundwater system. The most conspicuous change in chemistry of groundwater is relative enrichment of SO4. The interpretation of data reveals that SO4 has not been acquired through water–rock interaction. The source of SO4 is anthropogenic. Sugar factories alone are responsible for this potential environmental hazard.  相似文献   

13.
The Heihe River Basin is a typical arid inland river basin for examining stress on groundwater resources in northwest China. The basin is composed of large volumes of unconsolidated Quaternary sediments of widely differing grain size, and during the past half century, rapid socio-economic development has created an increased demand for groundwater resources. Understanding the hydrogeochemical processes of groundwater and water quality is important for sustainable development and effective management of groundwater resources in the Heihe River basin. To this end, a total of 30 representative groundwater samples were collected from different wells to monitor the water chemistry of various ions and its quality for irrigation. Chemical analysis shows that water presents a large spatial variability of chemical facies (SO4 2−–HCO3−, SO4 2−–Cl−, and Cl−–SO4 2−) as groundwater flow from recharge area to discharge area. The ionic ratio indicates positive correlation between the flowing pairs of parameters: Cl− and Na+(r = 0.95), SO4 2− and Na+ (r = 0.84), HCO3 − and Mg2+(r = 0.86), and SO4 2− and Ca2+ (r = 0.91). Dissolution of minerals, such as halite, gypsum, dolomite, silicate, and Mirabilite (Na2SO4·10H2O) in the sediments results in the Cl−, SO4 2−, HCO3 −, Na+, Ca2+ and Mg2+ content in the groundwater. Other reactions, such as evaporation, ion exchange, and deposition also influence the water composition. The suitability of the groundwater for irrigation was assessed based on the US Salinity Laboratory salinity classification and the Wilcox diagram. The results show that most of the groundwater samples are suitable for irrigation uses barring a few locations in the dessert region in the northern sub-basin.  相似文献   

14.
Over-exploitation of groundwater results in decline of water levels, leading to intrusion of salt water along the coastal region, which is a natural phenomenon. A groundwater quality survey has been carried out to assess such phenomena along the coast of Visakhapatnam, Andhra Pradesh, India. Brackish groundwaters are observed in most of the wells. The rest of the wells show a fresh water environment. The factors responsible for the brackish groundwater quality with respect to the influence of seawater are assessed, using the standard ionic ratios, such as Ca2+:Mg2+, TA:TH and Cl−:HCO− 3. Results suggest that the brackish nature in most of the groundwaters is not due to the seawater influence, but is caused by the hydrogeochemical process. Some influence of seawater on the groundwater quality is observed along the rock fractures. The combined effect of seawater and urban wastewaters is due to the inferior quality of groundwater in a few wells, where they are at topographic lows close to the coast.  相似文献   

15.
The aim of this study was to determine geochemical properties of groundwater and thermal water in the Misli Basin and to assess thermal water intrusion into shallow groundwater due to over-extraction. According to isotope and hydrochemical analyses results, sampled waters can be divided into three groups: cold, thermal, and mixed waters. Only a few waters reach water–rock chemical equilibrium. Thermal waters in the area are characterized by Na+–Cl−–HCO3−, while the cold waters by CaHCO3 facies. On the basis of isotope results, thermal waters in the Misli basin are meteoric origin. In particular, δ18O and δ2H values of shallow groundwater vary from −10.2 to −12.2‰ and −71.2 to −82‰, while those of thermal waters range from −7.8 to −10.1‰ and from −67 to −74‰, respectively. The tritium values of shallow groundwater having short circulation as young waters coming from wells that range from 30 to 70 m in depth vary from 10 to 14 TU. The average tritium activity of groundwater in depths more than 100 m is 1.59 ± 1.16, which indicates long circulation. The rapid infiltration of the precipitation, the recycling of the evaporated irrigation water, the influence of thermal fluids and the heterogeneity of the aquifer make it difficult to determine groundwater quality changes in the Misli Basin. Obtained results show that further lowering of the groundwater table by over-consumption will cause further intrusion of thermal water which resulted in high mineral content into the fresh groundwater aquifer. Because of this phenomenon, the concentrations of some chemical components which impairs water quality in terms of irrigation purposes in shallow groundwaters, such as Na+, B, and Cl−, are highy probably expected to increase in time.  相似文献   

16.
Groundwater regime and mineralization process in moraine sandy loam and peat soils of the active sulphatic karst zone (karst processes develop in the Upper Devonian gypsum–dolomites) in Lithuania and the dependence of chemical compounds concentrations on water level fluctuations are reviewed. According to ion sum, groundwater mineralization in peat soil is 1.1–1.3 times higher than in loam soil. Based on this result, lower levels of groundwater predetermine a more intensive mineralization process. A stronger correlation was determined between groundwater levels and concentrations of chemical compounds (Ca2+, Mg2+, SO4 2− and HCO3 −) enhancing groundwater mineralization. In mineral soil (sandy loam) nitrate (NO3)− concentration is highly influenced by changing stages of groundwater level as well as by nearby sinkholes.  相似文献   

17.
In this study, 92 groundwater samples were collected from the Attica region (Greece). Moreover, geographical information system database, geochemistry of groundwater samples and statistics were applied. These were used for studying the chemical parameters (NO3 −, Mg2+, Ca2+, Cl−, and Na+) and conductivity spatial distribution and for assessing their environmental impact. The ranges of chemical parameters of the water samples (in mg L−1) are: NO3 − 1–306, Mg2+ 2–293, Ca2+ 3–453, Cl− 5–1,988, and Na+ 4–475. The elevated concentrations of sodium, Mg2+, Cl− are attributed to natural contamination (seawater intrusion). On the other hand, NO3 − elevated concentrations are attributed to anthropogenic contamination (nitrate fertilizers). The results of the GIS analysis showed that elevated values of Na+, Mg2+, Cl− are related to shrubby and sparsely vegetated areas, while elevated values of NO3 − are connected with urban and agricultural areas.  相似文献   

18.
The degradation of groundwater quality, which has been noted in the recent years, is closely connected to the intensification of agriculture, the unreasonable use of chemical fertilizers and the excess consumption of large volumes of irrigation water. In the hilly region of central Thessaly in Greece, which suffers the consequences of intense agricultural use, a hydrogeological study is carried out, taking groundwater samples from springs and boreholes in the Neogene aquifers. The aim of this study is the investigation of irrigation management, water quality and suitability for various uses (water supply, irrigation), the degradation degree and the spatial distribution of pollutants using GIS. The following hydrochemical types prevail in the groundwater of the study area: Ca–Mg–HCO3, Mg–Ca–Na–HCO3 and Na–HCO3. In the above shallow aquifers, especially high values of NO3 − (31.7–299.0), NH4 + (0.12–1.11), NO2 − (0.018–0.109), PO4 3− (0.07–0.55), SO4 2− (47.5–146.5) and Cl− (24.8–146.5) are found, particularly near inhabited areas (values are in mg L−1). The water of shallow aquifers is considered unsuitable for human use due to their high polluting load, while the water of the deeper aquifers is suitable for human consumption. Regarding water suitability for irrigation, the evaluation of SAR (0.153–7.397) and EC (481–1,680 μS cm−1) resulted in classification category ‘C3S1’, indicating high salinity and low sodium water which can be used for irrigation in most soils and crops with little to medium danger of development of exchangeable sodium and salinity. The statistical data analysis, the factor analysis and the GIS application have brought out the vulnerable-problematic zones in chemical compounds of nitrogen and phosphates. The groundwater quality degradation is localized and related exclusively to human activities. Based on 2005 and 2008 estimates, the annual safe yield of the region’s aquifers were nearly 41.95 MCM. However, the existing situation is that 6.37 MCM of water is over extracted from these aquifers.  相似文献   

19.
Conventional graphical and statistical methods were used with water quality indices to characterize the hydrochemistry of groundwater from the northern part of the Volta region of Ghana. The objective was to determine the processes that affect the hydrochemistry and the variation of these processes in space among the three main geological terrains: the Buem formation, Voltaian System and the Togo series that underlie the area, and to determine the suitability of groundwater from the area for drinking purposes. The Q-mode cluster analysis reveals three main water groups. The groups established from the Q-mode HCA appear to indicate different degrees of weathering which could further indicate varying levels of fracturing aquifer hydraulic properties. R-mode HCA and factor analysis (using varimax rotation and Kaiser Criterion) were then applied to determine the significant sources of variation in the hydrochemistry. This study finds that groundwater hydrochemistry in the area is controlled by the weathering of silicate and carbonate minerals, as well as the chemistry of infiltrating precipitation. Mineral activity diagrams for the CaO–Na2O–Al2O3–SiO2–H2O and CaO–MgO–Al2O3–SiO2–H2O systems plotted for the area indicate stability in the smectite field and attribute hydrochemistry to the weathering of silicate minerals. Silicate mineral weathering and the effects of precipitation appear to be pervasive among all the three main geological terrains, whereas carbonate weathering is localized among the Voltaian aquifers. Cation exchange does not appear to play a significant role in the hydrochemistry but mild Water quality indices (WQI) were calculated for the samples using the concentrations of Na+, Ca2+, Mg2+, Cl−, NO3 −, F−, and EC at the various sample locations. The WQI values indicate that groundwater from the study area is of excellent quality for drinking purposes. WQI values from groundwater samples are averagely higher than samples taken from surface water sources in the area. This implies that geology has had an impact on the WQI of groundwater in the area.  相似文献   

20.
Groundwater in Palnad sub-basin is alkaline in nature and Na+-Cl−-HCO3− type around Macherla-Karempudi area in Guntur district, Andhra Pradesh. Total dissolved solids (TDS) show strong positive correlation with Cl−, Na+, Ca2+ and Mg2+, and positive correlation with SO42−, K+ and HCO3−. Calcareous Narji Formation is the dominant aquifer lithology, and water-rock interaction controls the groundwater chemistry of the area. Chloro-alkaline indices (CAI) are positive at Miriyala, Adigopula, Mutukuru, Macherla and Durgi suggesting replacement of Na+ and K+ ions from water by Mg++ and Ca++ ions from country rock through base exchange reactions. Negative CAI values are recorded at Terala, Rayavaram and Nehrunagar, which indicate exchange of Na+ and K+ from the rock as cation-anion exchange reaction (chloro-alkaline disequilibrium). TDS range from 91 to 7100 ppm (Avg. 835 ppm) and exceed the prescribed limit of drinking water around Mutukuru, Durgi, Rayavaram, Khambampadu and Ammanizamalmadaka areas. Scanty rainfall and insufficient groundwater recharge are the prime factors responsible for high salinity in the area. Fluoride content ranges from <1 to 3.8 ppm and contaminated areas were identified around Macherla (1 sq km; 3.8ppm), Mandadi (1 sq km, 2.1ppm) and Adigopula (2 sq km, <1 to 3.7 ppm). The % Na+ content varies from 17 to 85 with the mean value of 57, and eighty (80) samples showed higher %Na+ in comparison to the prescribed limit of 60 for irrigation water. Sodium Adsorption Ratio (SAR) and % Na+ in relation to total salt concentration indicate that groundwater (51%) mostly falls under doubtful to poor quality for irrigation purpose. Groundwater of Adigopula village is fluoride contaminated and remedial measures are suggested to improve the water quality.  相似文献   

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