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 46 毫秒
1.
This study represents air quality data of SO2 and As concentrations around the mining–metallurgical complex Bor (Serbia) from 1994 to 2008. Daily and annual SO2 concentrations greatly exceed current air quality standards in the studied area. The “hot spot” with the highest SO2 and As annual concentrations during 15 years was the urban-industrial area (the town core). Daily SO2 concentrations and meteorological parameters during the period from 2005 to 2008 were statistically analysed to develop suitable prediction equations for daily SO2 concentrations. Anode copper production is an important but not the only factor that has influence on SO2 concentrations. By stepwise multiple linear regression analysis, it was determined that daily SO2 concentrations are most influenced by maximum wind gust, relative humidity and air temperature at all the measuring sites. The prediction equations of daily SO2 concentrations represent a good model with regression coefficients from 0.854 to 0.926 at all the measuring sites. Correlation analysis showed that eastern and western winds increase SO2 concentrations, thus increasing the health risk of the inhabitants in the study area.  相似文献   

2.
Logistics in China has grown rapidly; in 2015, the freight volume has reached 41 billion ton, increasing by 4.4% year-on-year. At the same time, the pollutant emissions from freight cars account for 70% of total emissions of motor vehicles, which severely affected the air quality. The purpose of this paper is to investigate the effect of logistics on air pollution; we used a new methodology based on vector autoregression of freight turnover, gross domestic product, and urban population. We selected Beijing as our test and created a model using time series data for the period 2000–2014. In this model, permanent residents, freight turnover, and SO2 emission were used as proxies for population size, logistic services, and degree of air pollution. Our analyses showed that the expansion of logistic services had the biggest effect on air pollution. Moreover, impulse response analysis revealed that logistic growth caused more serious air pollution over a short time, with an ongoing negative effect. GDP growth was only weakly correlated with air pollution, while urban population growth appeared to have little effect.  相似文献   

3.
People living in the urban area and the surrounding suburban area have disparities in exposure and health risks due to different levels of ambient air pollutants. The main objective of this study is to investigate the concentrations, seasonal variations, and related health risks of ambient air pollutants (PM10, NO2, and SO2) in urban and suburban areas of Ningbo, China. The results showed that the average PM10, NO2, and SO2 concentrations in the urban area were 85.2, 49.3, and 37.4 μg/m3, which were 1.13, 1.25, and 1.41 times the values of the suburban area during the period of March 2009 to February 2010. For the potential health risk analysis, the residents have been divided into four age categories namely, infants, children (1 year), children (8–10 years), and adults. The analysis took into account age-specific breathing rates, body weights for different age categories. The results showed that the potential health risks to respiratory disease for all age categories living in urban area were higher than those in suburban area.  相似文献   

4.
Understanding climate during the last interglacial is critical for understanding how modern climate change differs from purely naturally forced climate change. Here we present the first high-resolution ice core record of the last interglacial and transition to the subsequent glacial period from Antarctica and the first glaciochemical record for this period from West Antarctica. Samples were collected from a horizontal ice trench in the Mt. Moulton Blue Ice Area (BIA) in West Antarctica and analyzed for their soluble major anions (Cl?, NO3?, SO42-), major and trace elements (Na, Mg, Ca, Sr, Cd, Cs, Ba, La, Ce, Pr, Pb, Bi, U, As, Al, S, Ti, V, Cr, Mn, Fe, Co, Cu, Zn) and water hydrogen isotopes (δD). The last interglacial is characterized by warmer temperatures (δD), weakened atmospheric circulation (dust elements, seasalts aerosols), decreased sea ice extent (Na, nssSO42-) and decreased oceanic productivity (nssSO42-). A combined examination of Mt. Moulton seasalts, dust, nssSO42- and δD records indicates that the last interglacial was extremely stable compared to glacial age climate events and it ended through a long period of gradual cooling unlike that projected for future Holocene climate.  相似文献   

5.
《Atmósfera》2014,27(4):403-410
A simple numerical experiment to evaluate the influence of model resolution on estimates of ambient air quality and associated human exposure is presented. This is done based on annual mean NO2 concentration fields for the agglomeration of Brussels and surroundings, simulated by the deterministic urban/regional-scale AURORA model at a resolution of 1 km. These NO2 concentration fields were used to calculate domain-wide exposure, which is defined here as the population density-weighted concentration. It was found that exposure decreased by 38% when degrading the resolution of the model from 1 to 64 km. A straightforward analysis revealed that this exposure reduction could be explained by the covariance between the concentration and population density patterns.  相似文献   

6.
Since the last eruption of the Fossa crater in 1888–1890, intense volcanic degassing has been remaining on Vulcano Island of Sicily (Italy). Toxic sulfur dioxide (SO2) of the solfataric action in this area represents, when inhaled, a permanent natural hazard harming humans. Approximately 500 permanent residents live and 15,000 tourists visit during the summer time the Porto village in the North of Vulcano Island. A cross-disciplinary fuzzy logic risk assessment has been conducted to evaluate health risks of human individuals exposed to higher SO2-concentrations C over certain exposure times t. The simple approach, based on fuzzy set theory, explains health risks semantically by words rather than by numbers. Advantages of this approach are, first, experts, non-experts, decision makers, or the public are able to understand and communicate risk degrees by words without using numbers. Second, in comparison to other risk definitions, the risk is not equal to the vulnerability; it is based on the hazard (SO2-gas clouds) and vulnerability (health effects) in combination. Third, risk levels can be still estimated even when limited or no statistical information is available, e.g., high SO2-concentrations or long exposure times. Moreover, human health risks were determined for C−t-scenarios based on threshold values of the European Union and the World Health Organization. Independently, two additional methods were used to determine the proportions of the population who are exposed to levels of SO2 at which health effects may be expected and also safety zones for civil protection around the degassing fields. In conclusion, SO2-gas concentrations in many parts of Vulcano Island go beyond the proclaimed alert threshold of the European Union and the World Health Organization. For example, the results show that sensitive individuals, such as asthmatics, young children, or elderly people, should not be exposed at any time to the degassing areas in Porto di Levante and at the NE-rim of the Fossa crater. In contrast, healthy non-sensitive individuals should be exposed less than 10 min to the SO2-clouds at these degassing areas, while hiking on the crater rim.  相似文献   

7.
Atmospheric pollution is one of the main agents of decay in monuments and other works of art located in industrialised urban centres. SO2 is a permanent and abundant component of air pollution and, although it does not have an immediate visual effect, after continuous exposure, it can cause irreversible damage to building materials. Marble is one of the most commonly used ornamental stones in historical monuments and its mineralogical composition makes it very susceptible to damage caused by exposure to SO2. To measure the chemical reactions caused on marble by the action of atmosphere rich in SO2, selected calcitic and dolomitic samples were altered by weathering accelerated test. For this, seven marble types (four calcitic and three dolomitic) were exposed to high concentration of sulphur dioxide for 24 h in a climate chamber under controlled temperature and humidity conditions (20 °C and > 90 % HR). Changes on marble surfaces caused by reactions of SO2 with calcite and dolomite were studied using two non-destructive techniques: chromatic change by means of colorimetry and chemical analysis using X-ray photoelectron spectroscopy (XPS). The development of new mineral phases was also observed by scanning electron microscopy. Colorimetric analysis revealed a decrease in lightness and chromatic parameters suggesting that these changes were due to the development of new mineral phases in all marbles. The XPS technique, which is generally used in the analysis of metals, is relatively new in the field of stone deterioration. It enabled us to recognise the development of sulphites and sulphates on marble surfaces with high precision, after just 24 h of exposure to high SO2 concentrations and to distinguish different decay paths for calcitic and dolomitic marbles.  相似文献   

8.
There is a great demand for estimating the ambient air pollutant background concentrations in order to assess the effectiveness of different emission control strategies. In this paper, the background concentrations of four pollutants, namely sulfur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), and ozone (O3) pollutants in urban, suburban, and rural environments were investigated using Kolmogorov–Zurbenko (KZ) filter technique. Air quality data from monitoring stations over a period of 4 years (2007–2010) was analyzed for three locations in Kuwait, namely urban, suburban, and rural. The spatial and temporal (daily, weekly, and monthly) variations of the four pollutants were analyzed. The results show that the levels of ambient air pollutant background concentrations were high in the urban site compared to suburban and rural area. The diurnal variation of SO2 concentration showed an early morning peak, while the diurnal variation of NOx concentration constituted has two peaks, one was in the early morning hours (5 to 8 a.m.) and the second was in nighttime hours (8 to 11 p.m.). These two peaks were observed at all three locations. The monthly background NOx concentration reached a maximum in winter and minimum in summer. Diurnal variation of CO concentration showed a similar trend to SO2 concentrations in all three locations. Because of the photochemical reactions that occur in the atmosphere, the background concentration of O3 showed an inverse relation with respect to background concentration of NOx.  相似文献   

9.
In order to investigate the effect of Thiobacillusferrooxidans on the oxidation of pyrite, two parallel experiments, which employed H2SO4 solutions and acidic solutions inoculated with ThiobaciUus ferrooxidans, were designed and carried out at 30℃. The initial pH of the two solutions was adjusted to 2.5 by dropwise addition of concentrated sulphuric acid. The surfaces of pyrite before exposure to leaching solutions and after exposure to the H2SO4 solutions and acidic solutions inoculated with Thiobacillus ferrooxidans were observed by scanning electron microscopy （SEM）. There were a variety of erosion patterns by Thiobacillusferrooxidans on the bio-leached pyrite surfaces. A conclusion can be drawn that the oxidation of pyrite might have been caused by erosion of the surfaces. Attachment of the bacteria to pyrite surfaces resulted in erosion pits, leading to the oxidation of pyrite. It is possible that the direct mechanism plays the most important role in the oxidation of pyrite. The changes in iron ion concentrations of both the experimental solutions with time suggest that ThiobaciUus ferrooxidans can enhance greatly the oxidation of pyrite.  相似文献   

10.
Sulfur dioxide measured at the Visitor’s Center of Hawai’i Volcanoes National Park, USA exhibits seasonal and diurnal patterns and is sensitive to rainfall, but the relationship between wind direction and SO2 is too inconsistent to support deterministic predictions of hourly SO2 based on hourly wind direction. Although SO2 at the Visitor Center has usually been below regulatory levels, high SO2 levels and adverse health effects remain a concern. This investigation identified patterns in hourly SO2 based on wind direction, time of day, month, and rainfall occurrence using 4 years of hourly data. Empirical probabilities were investigated using a Bayesian approach. Winds from the volcanic vents were rare, but when they did occur SO2 was elevated about half of the time. Conversely, half of the hours with elevated SO2 occurred when volcanic vents were not directly upwind. Episodes of elevated SO2 tended to occur during the months of November–March and between 8:00 a.m. and 5:00 p.m. Rainfall was associated with a marked reduction in SO2 (29–81% depending on wind direction). Individuals that wish to avoid exposure to volcanic fumes can take these patterns into account.  相似文献   

11.
Summary The crystal structure of the tetragonal fumarole mineral nabokoite, Cu7TeO4(SO4)5 · KCl (a=9.833 (1).Å,c=20.591(2) Å, space groupP 4/ncc, Z=4) was determined by single crystal X-ray methods on type material from Kamchatka. The structure contains complicated {[CU7TeO4(SO4)4]SO4} sheets that are intercalated by K and Cl ions. Nabokoite presents the first example of a Te(IV)O4 pyramid with exactly tetragonal symmetry. The K ions have a somewhat unusual, rather flat coordination.
Die Kristallstruktur des Nabokoits, Cu7TeO4(SO4)5 · KCl: Das erste Beispiel für eine Te(IV)O4-Pyramide mit exakt tetragonaler Symmetrie
Zusammenfassung Die Kristallstruktur des tetragonalen Fumarolenminerals Nabokoit, Cu7TeO4(SO4)5 · KCl (a=9,833(1)Å,c=20,591(2)Å, RaumgruppeP 4/ncc, Z=4) wurde an Typ-Material von Kamtschatka mit Röntgen-Einkristallmethoden bestimmt. Die Struktur enthält komplizierte [Cu7TeO4(SO4)4]SO4-Schichten, die durch K- und Cl-Ionen verbunden werden. Nabokoit liefert das erste Beispiel für eine Te(IV)O4-Pyramide mit exakt tetragonaler Symmetrie. Die K-Ionen haben eine etwas ungewöhnliche, ziemlich flache Koordination.

With 2 Figures  相似文献   

12.
Carbonates often accompany lake and lake‐margin deposits in both modern and ancient geological settings. If these carbonates are formed in standing water, their stable isotope values reflect the aquatic chemistry at the time of precipitation and may provide a proxy for determining regional hydrologic conditions. Carbonate rhizoliths and water samples were collected from a playa lake in eastern Nevada. Pilot Valley (～43°N) is a closed‐basin, remnant playa from the Quaternary desiccation of palaeo‐Lake Bonneville. Water is added to the playa margin by free convection of dense brines to the east and forced convection of freshwater off the alluvial fan to the west. Both freshwater and saline springs dot the playa margin at the base of an alluvial fan. Water samples collected from seven springs show a range from ?16 to ?0·2‰ (Vienna Standard Mean Ocean Water), and are consistent with published values. The δ18Ocalcite values from rhizolith samples range from ?18·3 to ?6·7‰ (Vienna Pee Dee Belemnite), and the average is ?12‰ V‐PDB (1 ? σ SD 2‰). With the exception of samples from Little Salt Spring, the range in the δ18Ocalcite values collected from the rhizoliths confirms that they form in equilibrium with ambient water conditions on the playa. The initial geochemical conditions for the spring waters are dictated by local hydrology: freshwater springs emerge in the northern part of the basin to the east of a broad alluvial fan, and more saline springs emerge to the south where the influence of the alluvial fan diminishes. Rhizoliths are only found near the southern saline springs and their δ13Ccalcite values, along with their morphology, indicate that they only form around saltgrass (Distichlis sp.). As the residence time of water on the playa increases, evaporation, temperature change and biological processes alter the aquatic chemistry and initiate calcite precipitation around the plant stems. The range in δ18Ocalcite values from each location reflects environmental controls (e.g. evaporation and temperature change). These rhizoliths faithfully record ambient aquatic conditions during formation (e.g. geochemistry and water depth), but only record a partial annual signal that is constrained by saltgrass growth and the presence of standing water on the playa margin.  相似文献   

13.
We present for the first time a self-consistent methodology connecting volcanological field data to global climate model estimates for a regional time series of explosive volcanic events. Using the petrologic method, we estimated SO2 emissions from 36 detected Plinian volcanic eruptions occurring at the Central American Volcanic Arc (CAVA) during the past 200,000 years. Together with simple parametrized relationships collected from past studies, we derive estimates of global maximum volcanic aerosol optical depth (AOD) and radiative forcing (RF) describing the effect of each eruption on radiation reaching the Earth’s surface. In parallel, AOD and RF time series for selected CAVA eruptions are simulated with the global aerosol model MAECHAM5-HAM, which shows a relationship between stratospheric SO2 injection and maximum global mean AOD that is linear for smaller volcanic eruptions (<5 Mt SO2) and nonlinear for larger ones (≥5 Mt SO2) and is qualitatively and quantitatively consistent with the relationship used in the simple parametrized approximation. Potential climate impacts of the selected CAVA eruptions are estimated using an earth system model of intermediate complexity by RF time series derived by (1) directly from the global aerosol model and (2) from the simple parametrized approximation assuming a 12-month exponential decay of global AOD. We find that while the maximum AOD and RF values are consistent between the two methods, their temporal evolutions are significantly different. As a result, simulated global maximum temperature anomalies and the duration of the temperature response depend on which RF time series is used, varying between 2 and 3 K and 60 and 90 years for the largest eruption of the CAVA dataset. Comparing the recurrence time of eruptions, based on the CAVA dataset, with the duration of climate impacts, based on the model results, we conclude that cumulative impacts due to successive eruptions are unlikely. The methodology and results presented here can be used to calculate approximate volcanic forcings and potential climate impacts from sulfur emissions, sulfate aerosol or AOD data for any eruption that injects sulfur into the tropical stratosphere.  相似文献   

14.
Yadav  Ganesh  Singh  R. B.  Anand  Subhash  Pandey  B. W.  Mohanty  Ashutosh  Dash  Sushree Sangita 《GeoJournal》2021,87(4):469-483

Ambient air pollution, particularly in the urban environment of developing countries, has turned out to be a major health risk factor. We explore the compounded impact of age sensitivity, exposure, poverty, co-morbidity, etc., along with composite air pollution in determining morbidity and health burden of people in Lucknow, India. This cross-sectional study is confined to analyse respiratory health status across different socio-economic and geographic locations using n = 140 in-depth questionnaire method. We used mean daily ambient air pollution data of PM10, PM2.5, SO2, and NO2 for the 2008–2018 period. We used the ecological model framework to assess the risk at different hierarchical levels and compounded severity on a spatial scale. We also used Logistic regression model with log odds and odds ratio to analyze the association of risks outcomes with composite air pollution scores calculated using the principal component analysis method. There is a strong association of location-specific respiratory disease prevalence with an overall 32 percent prevalence. The prevalence of ecological model 1 (individual domain) is 4.3 percent, while ecological model 2 (community domain) has the highest prevalence at 32.4 percent. The logistic regression model shows that respiratory disease load is positively associated with age sensitivity (P < .001) and composite pollution level (P < .001). For another model with suffocation as the outcome variable, composite pollution level (P < .001) and exposure (P < .001) are positively associated. Optimum interventions are required at Ecological models 1, 2, and 3 levels for better respiratory health outcomes.

  相似文献   

15.
This contribution describes the setup and operating procedures of the first operational laser ablation microprobe for stable (sulphur) isotope analysis in Australia as well as some brief geological applications. A significant feature on this laser ablation microprobe is automated gas purification and analysis; operator control is only required to locate and ablate sample targets. As with other laboratories, samples were ablated in an oxygen atmosphere, producing a SO2/O2 gas mixture. SO2 was separated from this mixture by either of two techniques. In the first technique, SO2 was condensed into a liquid N2 trap by cryogenic pumping, and O2 was pumped away. This resulted in the collection of 60–70% of the produced SO2. In the second technique, SO2 was condensed into a liquid N2 trap as the SO2/O2 mixture was slowly bled away. This technique collected 90–95% of the SO2, with a small fractionation of 0.16%. Laser ablation and SO2 collection via the second technique required a mineral dependent, additive correction of 2.85–5.75% to convert raw δ34S values to δ34SCDT. These correction factors are mineral and laboratory dependent, and from our data, seem to be dependent on the quality of polish of the ablated sample. Precision (1σ) of laser ablation sulphur isotope analysis is 0.4–0.5%o for 150 μm ablation craters.

Preliminary results of studies on samples from the Broken Hill, Hellyer and active sea floor Pacmanus deposits indicate that laser ablation microprobe analysis can show subtle variations in δ34S not apparent using either conventional or SHRIMP analysis. Laser ablation analysis indicates a larger range, but similar mean values, to conventional analysis on the same samples.  相似文献   

16.
We report on extensive deposition measurements of sulfur dioxide (SO2) on three types of commonly used building stones (Obernkirchen sandstone, Sand sandstone, Ihrlerstein sandstone). The deposition velocities on the three materials were determined in a number of measuring campaigns at different sites with different levels of air pollution. The measurements clearly imply that there is a strong influence of SO2 concentration on the deposition velocity. With increasing concentration there is a strong decrease in the deposition velocity. To understand this deposition behavior a simple model with a single rate constant as the only adjustable parameter was established. Rate constants for the three stone materials were determined by least squares analysis and good agreement between experimental and calculated deposition velocities was obtained. According to the model treatment the surface resistance of stone materials increases with increasing SO2 concentration due to a decrease of the pH in surface films. It follows from the concentration dependence of the deposition velocity that emission control measures for the reduction of ambient SO2 concentrations do not lead to a proportional reduction of the SO2 deposition. At low SO2 concentrations the differences in the deposition behavior of different stone materials diminish and stone surfaces behave like ideal absorbers under such conditions, i.e., the deposition velocity is controlled by the aerodynamic resistance.  相似文献   

17.
《Applied Geochemistry》2004,19(3):343-358
Ion-exchange batch experiments were run on Cretaceous (Magothy aquifer) clay cores from a nearshore borehole and an inland borehole on Long Island, NY, to determine the origin of high SO42− concentrations in ground water. Desorption batch tests indicate that the amounts of SO42− released from the core samples are much greater (980–4700 μg/g of sediment) than the concentrations in ground-water samples. The locally high SO42− concentrations in pore water extracted from cores are consistent with the overall increase in SO42− concentrations in ground water along Magothy flow paths. Results of the sorption batch tests indicate that SO42− sorption onto clay is small but significant (40–120 μg/g of sediment) in the low-pH (<5) pore water of clays, and a significant part of the SO42− in Magothy pore water may result from the oxidation of FeS2 by dissolved Fe(III). The acidic conditions that result from FeS2 oxidation in acidic pore water should result in greater sorption of SO42− and other anions onto protonated surfaces than in neutral-pH pore water. Comparison of the amounts of Cl− released from a clay core sample in desorption batch tests (4 μg/g of sediment) with the amounts of Cl− sorbed to the same clay in sorption tests (3.7–5 μg/g) indicates that the high concentrations of Cl− in pore water did not originate from connate seawater but were desorbed from sediment that was previously in contact with seawater. Furthermore, a hypothetical seawater transgression in the past is consistent with the observed pattern of sorbed cation complexes in the Magothy cores and could be a significant source of high SO42− concentrations in Magothy ground water.  相似文献   

18.
Over the past few decades, substantial progress has been made to overcome the technical difficulties of continuously measuring volcanic SO2 emissions. However, measurements of CO2 emissions still present many difficulties, partly due to the lack of instruments that can directly measure CO2 emissions and partly due to its strong atmospheric background. In order to overcome these difficulties, a commonly taken approach is to combine differential optical absorption spectroscopy (DOAS) by using NOVAC scan-DOAS instruments for continuous measurements of crateric SO2 emissions, and electrochemical/NDIR multi-component gas analyser system (multi-GAS) instruments for measuring CO2/SO2 ratios of excerpts of the volcanic plume. This study aims to quantify the representativeness of excerpts of CO2/SO2 ratios measured by Multi-GAS as a fraction of the whole plume composition, by comparison with simultaneously measured CO2/SO2 ratios using cross-crater Fourier transform infrared spectroscopy (FTIR). Two study cases are presented: Telica volcano (Nicaragua), with a homogenous plume, quiescent degassing from a deep source and ambient temperature, and Turrialba volcano (Costa Rica), which has a non-homogeneous plume from three main sources with different compositions and temperatures. Our comparison shows that in our “easier case” (Telica), FTIR and Multi-GAS CO2/SO2 ratios agree within a factor about 3 %. In our “complicated case” (Turrialba), Multi-GAS and FTIR yield CO2/SO2 ratios differing by approximately 13–25 % at most. These results suggest that a fair estimation of volcanic CO2 emissions can be provided by the combination of DOAS and Multi-GAS instruments for volcanoes with similar degassing conditions as Telica or Turrialba. Based on the results of this comparison, we report that by the time our measurements were made, Telica and Turrialba were emitting approximately 100 and 1,000 t day?1 of CO2, respectively.  相似文献   

19.
Due to its negative impact on the living environment of human beings, ambient air pollution has become a global challenge to human health. In this study, surface observations of six criteria air pollutants, including PM2.5, PM10, SO2, NO2, CO and O3, were collected to investigate the spatial and temporal variation in the Beijing–Tianjin–Hebei (BTH) region during 2013–2016 and to explore the relationships between atmospheric pollutants and meteorological variables using quantile regression model (QRM) and multiple linear regression model (MLRM). The results show that BTH region has experienced significant air pollution, and the southern part generally has more severe conditions. The annual average indicates clear decreasing trends of the particulate matters, SO2 and CO concentrations over the last 4 years and slight increasing trends of NO2 and O3 in several cities. The seasonal and monthly characteristics indicate that the concentrations of five species reach their maxima in the winter and their minima in the summer, whereas O3 has the opposite behaviour. Finally, the pseudo R2 values show that the QRMs have the best performance in the winter, followed by spring, fall, and summer. Specifically, all the meteorological factors have significant impacts on air pollution but change with pollutants and seasons. The MLRM results are generally consistent with the QRM results in all seasons, and the inconsistencies are more common in the fall and winter. The results of this research provide foundational knowledge for predicting the response of air quality to climate change in the BTH region.  相似文献   

20.
Hydrochemical investigations were carried out in Bahar area, Hamadan, western Iran, to assess the chemical composition of groundwater. The area falls in a semi-arid type of climate. In this area, groundwater has been exploited over the past century mainly for irrigation and water supply. A total of 135 representative groundwater samples were collected from different wells to monitor the water chemistry of various ions. Chemical analysis of the groundwater shows that the mean concentration of the cations is of the order Ca2+>Mg 2+>Na+>K+, while that for anions is SO42–>HCO3–>Cl–>NO3–. Statistical analyses indicate positive correlation between the following pairs of parameters Cl– and Mg 2+ (r=0.71), Cl– and Na+ (r=0.76), HCO3– and Na+ (r=0.56), SO42– and Mg2+ (r=0.76), SO42– and Na+ (r=0.69). Water presents a large spatial variability of the chemical facies (Ca-HCO3, Ca-SO4, Mg-HCO3, Mg-SO4, Na-HCO3) which is in relation to their interaction with the geological formations of the basin (carbonates, dolomite and various silicates) and evaporation. The hydrochemical types Ca-HCO3 and Ca-SO4 dominate the largest part of the studied area. The dissolution of halite, calcite, dolomite, and gypsum explains part of the contained Na +, Ca2+, Mg2+, Cl–, SO42– and HCO3–, but other processes, such as cation exchange and weathering of aluminosilicates also contribute to the water composition.  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