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1.
The groundwater of the Korba plain represents major water resources in Tunisia. The Plio‐Quaternary unconfined aquifer of the Cap‐Bon (north‐east Tunisia) is subject to the intensive agricultural activities and high groundwater pumping rates due to the increasing of the groundwater extraction. The degradation of the groundwater quality is characterized by the salinization phenomena. Groundwater were sampled and analysed for physic‐chemical parameters: Ca2+, Mg2+, Na+, K+, Cl‐, SO42‐, HCO3‐, NO3‐, pH, electrical conductivity (EC), and the temperature (T°). The hydrochemical analysis is coupled with the calculation of the saturation indexes (SI gypsum, SI halite, SI calcite and SI dolomite), ionic derivation and with the ion correlations compared to chloride concentrations: Na+/ Cl‐, Ca2+/ Cl‐ and Mg2+/ Cl‐ ratios. Seawater fractions in the groundwater were calculated using the chloride concentration. Those processes can be used as indicators of seawater intrusion progression. EC methods were also conducted to obtain new informations on the spatial scales and dynamics of the fresh water–seawater interface of coastal groundwater exchange. The mixing zone between freshwater and saltwater was clearly observed from the EC profile in the investigated area where a strong increase in EC with depth was observed, corresponding to the freshwater and saltwater interface. Results of hydrochemical study revealed the presence of direct cation exchange linked to seawater intrusion and dissolution processes associated with cations exchange. These results, together with EC investigation, indicated that the groundwater is affected by seawater intrusion and is still major actor as a source of salinization of the groundwater in Korba coastal plain. Further isotopic and hydrological investigations will be necessary to identify and more understood the underlying mechanisms. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

2.
The hydrochemical analyses of twenty-three springs were used to determine the properties and types of groundwater of the Tertiary-Quaternary Aquifer of northern Jordan. The result shows that the geological formation influences the quality of the investigated groundwater more than the anthropogenic factors. The water of the Quaternary-Tertiary aquifer is enriched in Ca++ due to the dissolution of the nearby carbonate rocks. The investigated water has a low EC values with Ca(Na)-HCO3 water type. Most springs belong to this hydrochemical facies except Malka. Groundwater in the Malka wells has high salinity with NaCl waters and a strong Ca(Mg)-HCO3 facies (900 to 1000 mg/l TDS). The area long-term hydrochemical data have been also evaluated; general trend of increase of the analyzed ion was observed. Bicarbonate represents the most abundant anion in the studied water, which exceeds the permissible limits. Nitrates (NO 3 ? ) also exceed the permissible limit and are the most common contaminant in the investigated water. Data on dissolved major and trace elements (K+, Na+, Mg2+, Ca2+, Cl?, SO 4 2? , Fe, Zn, Cu and Pb) in the investigated water revealed that the concentrations lie within the natural background range. The positive correlation values between various ions indicate that most of ions come from same lithological sources. According to the residual sodium carbonate, and EC values, the studied springs are suitable for agricultural purposes.  相似文献   

3.
Multivariate statistical techniques, cluster and factor analyses were applied on the Amman/Wadi Sir groundwater chemistry, Yarmouk River basin, north Jordan. The main objective was to investigate the main processes affecting the groundwater chemical quality and its evolution. The k‐means cluster analysis yields three groups with distinct ionic concentrations. Cluster 1 comprises the vast majority of the sampled wells, and the water that belongs to this cluster can be classified as freshwater. Cluster 2 comprises only 2% of the sampled wells; it has the highest ionic concentration. The water of this cluster can be classified as brackish water. Cluster 3 involves 23% of the sampled wells, and it has total ionic concentration intermediate to that of clusters 1 and 2. Factor analysis yields a three‐factor model, which explains 76.77% of the groundwater quality variation. Factor 1 ‘salinity factor’ involves EC, Na+, Cl‐, SO4‐2, K+ and Mg+2 and reflects groundwater salinization because of overpumping. Factor 2 ‘hardness factor’ includes Ca+2, HCO3‐ and the pH value and signifies soil–water/rock interaction. Factor 3 ‘nitrate factor’ involves only NO3‐ and points to groundwater contamination because of human activities, mainly untreated wastewater, and crops and animal cultivation in the unconfined portion of the aquifer. Factors 1 and 3 can be described as human‐induced factors, whereas factor 2 can be described as geogenic factor. Factors' scores were mapped to deduce the controlling processes on the groundwater chemistry. Stable isotope composition of 18O and 2H has revealed that the groundwater is a mixture of two water types. The radioactive isotopes tritium and 14 C were used to evaluate present day recharge to the aquifer and to estimate the groundwater age, respectively. Present day recharge to the groundwater is taking place in the unconfined portion of the aquifer as it is indicated by the measurable tritium content and low groundwater age. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

4.
A typical area, Gaomi City in China, was chosen to discuss the enrichment process of groundwater fluorine in sea water intrusion area. The groundwater had fluorine levels of 0.09–10.99 mg/L, with an average concentration of 1.38 mg/L. The high-fluorine groundwater was mainly distributed in the unconsolidated Quaternary sediments, where concentrations in 83.6% of the samples exceeded the national limit of 1.0 mg/L. The groundwater in the Quaternary sediments also had higher levels of Cl−, TDS, Mg2+, and pH and lower levels of Ca2+, Co, Ni, and Cu than that in the bedrock. The groundwater fluorine levels in the Quaternary sediments are positively correlated with Cl−, TDS, Mg2+, pH, and negatively correlated with Ca2+, γCa2+/γMg2+, Co, Ni, Cu. Geochemical indices of Cl− and TDS indicate sea water intrusion in the Quaternary high-fluorine groundwater area (F− > 1.0 mg/L), while they do not indicate any intrusion in the bedrock area. The chemical weathering of minerals was intensified with the intrusion of sea water. Cation exchange was confirmed to occur in the Quaternary sediments and was promoted by sea water intrusion. Cation exchange consumes part of groundwater Ca2+ and permits more F− dissolving. Consequently, in the Quaternary sediments, the groundwater was supersaturated with CaF2 minerals and undersaturated with MgF2 minerals when F− > 1.0 mg/L, while CaF2 and MgF2 minerals both are undersaturated when F− < 1.0 mg/L. Thus, the chemical weathering of minerals and cation exchange caused by sea water intrusion are the crucial processes controlling the groundwater fluorine levels, which should be considered when the groundwater fluorine enrichment mechanism is discussed along coastal zones.  相似文献   

5.
Abstract

On the basis of the degree of mineralization, the groundwater of Apan-Tochac sub-basin may be considered as fresh (TDS < 500 ppm). However, chlorination is necessary to make it fit for human consumption. Major ion analyses of over 235 water samples reveal a striking relationship between hydrochemical evolution and the groundwater flow system. A high content of total dissolved solids, and low values of the Ca:Mg ratio are present in wells located on the plain (discharge zone), whereas opposite conditions are associated with wells located in higher regions (recharge zone). Statistical data analysis using the method of principal components allowed to differentiation of two hydrochemical families: (a) low mineralization corresponding to the recharge zone, and (b) high mineralization corresponding to the discharge zone. Waters of the Ca + Mg + HCO3, and Na + Mg + HCO3 hydrochemical fades are present and the former is dominant. The water is slightly alkaline, having slight problems of salinity during the year owing mainly to Ca2+HCO3 ? and Na+Cl? salts. The hydrochemistry of the groundwater reflects the pattern of local groundwater flow for this sub-basin.  相似文献   

6.
The impact assessment of molasses‐based distillery‐effluent irrigation on groundwater quality around village Gajraula in the district of Jyotiba Phule Nagar, Uttar Pradesh, India was studied by sampling groundwater on monthly intervals consecutively for summer, winter and monsoon seasons during 2006–2007 and water quality parameters, viz. pH, electrical conductivity (EC), chloride (Cl?), sulphate (SO), nitrate (NO), chemical oxygen demand (COD), total solids (TS), total dissolved solids (TDS), sodium (Na+), potassium (K+), calcium (Ca2+), magnesium (Mg2+), zinc (Zn2+), iron (Fe3+), and total coliforms (TC) were monitored. Results depicted that the values of all parameters decreased with increasing depth of water table. Sulphate, nitrate and potassium contents were maximal in agricultural site during monsoon while EC, Cl?, TS, TDS, Na+, Ca2+, Mg2+, Zn, and Fe were maximal in industrial sites during summer. Groundwater samples of residential site harboured maximum coliforms especially during monsoon, highlighting threat to groundwater. Significant positive correlation matrix between coliforms with nitrate, sulphate and potassium ions explained their survival on these nutrients. To overcome this, important measures emphasizing improvement in effluent treatment technology matching site‐specific characteristics are recommended for eco‐friendly ferti‐irrigation.  相似文献   

7.
Three techniques for obtaining soil water solutions (gravitational and matrical waters extracted using both in situ tension lysimeters and in vitro pressure chambers) and their later chemical analysis were performed in order to know the evolution of the soil‐solution composition when water moves down through the soil, from the Ah soil horizon to the BwC‐ or C‐horizons of forest soils located in western Spain. Additionally, ion concentrations and water volumes of input waters to soil (canopy washout) and exported waters (drainage solutions from C‐horizons) were determined to establish the net balance of solutes in order to determine the rates of leaching or retention of ions. A generalized process of sorption or retention of most components (even Cl?) was observed, from the soil surface to the C‐horizon, in both gravitational and matrical waters, with H4SiO4, Mn2+, Na+, and SO42? being the net exported components from the soil through the groundwater. These results enhance the role of the recycling effect in these forest soils. The net percentages of elements retained in these forest soils, considering the inputs and the outputs balance, were 68% K+, 85% Ca2+, 58% Mg2+, 7% Al3+, 5% Fe3+, 34% Zn2+, 57% Cl?, and 20% NO3?, and about 75% of dissolved organic carbon was mineralized. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

8.
Stable isotopic (δDVSMOW and δ18OVSMOW) and geochemical signatures were employed to constrain the geochemical evolution and sources of groundwater recharge in the arid Shule River Basin, Northwestern China, where extensive groundwater extraction occurs for agricultural and domestic supply. Springs in the mountain front of the Qilian Mountains, the Yumen‐Tashi groundwater (YTG), and the Guazhou groundwater (GZG) were Ca‐HCO3, Ca‐Mg‐HCO3‐SO4 and Na‐Mg‐SO4‐Cl type waters, respectively. Total dissolved solids (TDS) and major ion (Mg2+, Na+, Ca2+, K+, SO42?, Cl? and NO3?) concentrations of groundwater gradually increase from the mountain front to the lower reaches of the Guazhou Basin. Geochemical evolution in groundwater was possibly due to a combination of mineral dissolution, mixing processes and evapotranspiration along groundwater flow paths. The isotopic and geochemical variations in melt water, springs, river water, YTG and GZG, together with the end‐member mixing analysis (EMMA) indicate that the springs in the mountain front mainly originate from precipitation, the infiltration of melt water and river in the upper reaches; the lateral groundwater from the mountain front and river water in the middle reaches are probably effective recharge sources for the YTG, while contribution of precipitation to YTG is extremely limited; the GZG is mainly recharged by lateral groundwater flow from the Yumen‐Tashi Basin and irrigation return flow. The general characteristics of groundwater in the Shule River Basin have been initially identified, and the results should facilitate integrated management of groundwater and surface water resources in the study area. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

9.
Abstract

The western reservoirs represent the principal groundwater system in Morocco. Demographic, industrial and agricultural developments during the last decade have markedly altered groundwater quality. The Mamora coastal aquifer system is among the Atlantic systems which are most heavily threatened by pollution. Agricultural and industrial activities, and rapid urban growth contribute to the pollution of the groundwater. Contamination transport is facilitated by a high permeability of the aquifer formations. In order to assess the actual groundwater quality of the Mamora aquifer and to understand the influence of the factors generating the pollution, an extensive multidisciplinary research programme is in progress, with hydrochemistry and microbiology playing essential roles. The present paper concerns the spatial distribution of physico-chemical parameters in the groundwater, subjected to domestic, industrial and agricultural pollution. Fifty-seven samples were analysed for several parameters (Ca2+, Mg2+, Na+, K+, Cl?, SO4 2?, HCO3 ?, NO3 ?, pH, electrical conductivity and temperature). The microbiological analysis of 143 samples reveals the presence of four kinds of indicator bacteria in the groundwater resources: faecal Streptococci, faecal coliform, Escherichia coli and Clostridium. The physico-chemical results and bacteriological monitoring show that the nitrate and bacteria concentrations exceed the maximum admissible levels, notably around pumping stations in the sectors of Sidi Taibi, Sidi Ahmed Taleb and Aïn Sbaâ. Contamination is generated by uncontrolled anthropogenic activities and accentuated by the high intrinsic vulnerability of the aquifer system. Several parameters appeared to exceed admissibility standards. Measures are recommended to prevent groundwater pollution in the region.  相似文献   

10.
巴丹吉林沙漠湖泊水化学空间分布特征   总被引：7，自引：2，他引：5  
通过对巴丹吉林沙漠腹地拐子湖-地质公园一线51个湖泊水,8个泉水,12个井水及1个雨水水样的水化学成分分析,初步探讨了沙漠湖泊水化学分布特征及其影响因素.结果表明由东南边缘至腹地湖泊总体上依次呈硫酸盐型-碳酸盐型-氯化物型分布.东南边缘以Na+、Cl-、SO24-为主的湖泊因矿化度分异,形成Ca2+、Mg2+含量不同的三种亚型,其中高矿化度的Na-Cl-(SO4)型湖泊在腹地湖泊群中也有出现,表现出地理上的不连续分布;边缘若干湖泊受局部地理环境的影响水离子多含Na+、Cl-、CO32-+HCO3-.综合分析表明湖泊水化学型的空间分异与区域气候差异和气候变化有关,湖水直接或间接地接受当地降水补给,但不排除外源地下水补给对其有一定贡献.通过对比不同时段部分沙漠湖泊水化学特征发现近十年以来腹地湖泊补给源或受气候干暖化影响使其水化学特性较边缘湖泊的变化大.  相似文献   

11.
Concentrations of major ions in surface waters of the rivers of Khara-Murin and Snezhnaya are compared based on data of many-year observations carried out in the 1950s and 2000s. The concentrations of HCO 3 ? , Cl?, Ca2+, Mg2+, Na+ + K+ are shown to be stable. A considerable increase in SO 4 ?2 concentration was revealed.  相似文献   

12.
The aim of this study is to identify, in a small catchment area located within a tropical forest, the pedological compartments in which the export of nutrients and chemical erosion of solutes occur during a stormflow event. The catchment area displays two types of lateral flow: (i) overland flow at the surface of the soil in the litter and root mat and (ii) groundwater flow in a macroporous subsurface horizon. We interpret the variations of stream‐water chemistry during a storm‐flow event using the separation of storm‐flow hydrograph data between overland and groundwater flow, and (Cl?) as a chemical parameter characterizing the residence time of water in the soil. It appears that K+ especially was released into the throughfall, whereas Ca++, Mg++ and Na+ were clearly released from the litter. K+ disappeared rapidly from soil solution, whereas Ca++ and Mg++ were more progressively absorbed by the vegetation. The Ca++ and Mg++ contents in groundwater increased with increasing residence time owing to the transpiration of trees. The export of H4SiO4 in the overland flow was moderate, i.e. 24% of total H4SiO4 export in the stream flow, as overland flow represented 39% of total runoff. The subsurface horizon—where active groundwater flow occurs—was successively affected by chemical erosion during the storm‐flow peak, and then by neoformation of kaolinite favoured by increasing water residence time. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

13.
Major‐ion compositions of groundwater are employed in this study of the water–rock interactions and hydrogeochemical evolution within a carbonate aquifer system. The groundwater samples were collected from boreholes or underground tunnels in the Ordovician limestone of Yanzhou Coalfield where catastrophic groundwater inflows can be hazardous to mining and impact use of the groundwater as a water supply. The concentration of total dissolved solid (TDS) ranged from 961 to 3555 mg/l and indicates moderately to highly mineralized water. The main water‐type of the middle Ordovician limestone groundwater is Ca‐Mg‐SO4, with SO42‐ ranging from 537 to 2297 mg/l, and average values of Ca2+ and Mg2+ of 455.7 and 116.6 mg/l, respectively. The water samples were supersaturated with respect to calcite and dolomite and undersaturated or saturated with respect to gypsum. Along the general flow direction, deduced from increases of TDS and Cl‐, the main water–rock interactions that caused hydrogeochemical evolution of the groundwater within the aquifer were the dissolution of gypsum, the precipitation of calcite, the dissolution or precipitation of dolomite, and ion exchange. Ion exchange is the major cause for the lower mole concentration of Ca2+ than that of SO42‐. The groundwater level of Ordovician aquifer is much higher than that of C‐P coal‐bearing aquifers, so the potential flow direction is upward, and the pyrite in coal is not a possible source of sulfate; additional data on the stable sulfur and oxygen isotopic composition of the sulfate may be helpful to identify its origin. Although ion exchange probably accounts for the higher mole concentration of Na+ than that of Cl‐, the dissolution of aluminosilicate cannot be ruled out. The data evaluation methods and results of this study could be useful in other areas to understand flow paths in aquifers and to provide information needed to identify the origin of groundwater. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

14.
The source and hydrochemical makeup of a stream reflects the connectivity between rainfall, groundwater, the stream, and is reflected to water quantity and quality of the catchment. However, in a semi-arid, thick, loess covered catchment, temporal variation of stream source and event associated behaviours are lesser known. Thus, the isotopic and chemical hydrographs in a widely distributed, deep loess, semi-arid catchment of the northern Chinese Loess Plateau were characterized to determine the source and hydrochemical behaviours of the stream during intra-rainfall events. Rainfall and streamflow were sampled during six hydrologic events coupled with measurements of stream baseflow and groundwater. The deuterium isotope (2H), major ions (Cl−, SO42−, NO3−, Ca2+, K+, Mg2+, and Na+) were evaluated in water samples obtained during rainfall events. Temporal variation of 2H and Cl− measured in the groundwater and stream baseflow prior to rainfall was similar; however, the isotope compositions of the streamflow fluctuated significantly and responded quickly to rainfall events, likely due to an infiltration excess, overland dominated surface runoff during torrential rainfall events. Time source separation using 2H demonstrated greater than 72% on average, the stream composition was event water during torrential rainfall events, with the proportion increasing with rainfall intensity. Solutes concentrations in the stream had loglinear relationships with stream discharge, with an outling anomaly with an example of an intra-rainfall event on Oct. 24, 2015. Stream Cl− behaved nonconservative during rainfall events, temporal variation of Cl− indicated a flush and washout at the onset of small rainfall events, a dilution but still high concentration pattern in high discharge and old water dominated in regression flow period. This study indicates rainfall intensity affects runoff responses in a semi-arid catchment, and the stored water in the thick, loess covered areas was less connected with stream runoff. Solute transport may threaten water quality in the area, requiring further analysis of the performance of the eco-restoration project.  相似文献   

15.
Clay aquitards are semipermeable membranes that allow groundwater flow while retarding solute migration has been researched extensively but also subjected to much debate. At present, there is no evidence of whether the physical and chemical properties of clay soil and the isotopic composition of pore water affect the semipermeable membrane effect. In this study, we collected clay samples from drilling cores (30–90 m) in the Hengshui area located in the North China Plain (NCP), then extracted pore water using a high-pressure squeezing device. Vertical hydrochemical and isotopic profile variation trends for the pore water were revealed using hydrochemical (Cl−, Na+, Ca2+, K+, Mg2+, and SO42−) and stable isotopic measurements of H, O and Cl. The results showed that the hydrochemical clay interlayer pore water of the saline aquifer is Cl/SO4-Na/Mg type and the average total dissolved solids (TDS) are 10.17 g/L. However, the hydrochemical clay aquitard pore water is of the Cl/SO4-Na/Ca type with an average TDS of 1.90 g/L. The hydrochemical clay interlayer pore water of aquifer II is of Cl-Na/Ca type with an average TDS of 1.10 g/L. Our results showed that the water quality of the aquifer II is not affected by the upper part of the saline aquifer, thus the clay aquitard acts as a significant barrier to salt movement. A polarization layer concentrated in ions was formed between the upper part of the saline aquifer and the clay aquitard. The concentration polarization layer increases the salt-inhibition effect. H, O and Cl isotopic composition results showed significant fractionation. The pore water of aquifer II lacked heavy isotopes (2H, 18O, 37Cl), but had significant heavy isotope enrichment in the concentrated polarized layer (the δ2H value was −76‰, the δ18O value was −8.4‰, and the δ37Cl value was 1.59‰). Hyperfiltration thus played a significant role in isotope fractionation.  相似文献   

16.
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17.
淮北临涣矿采煤沉陷区不同水体水化学特征及其影响因素   总被引：3，自引：0，他引：3  
为研究淮北临涣矿采煤沉陷区不同水体的补给水源及溶质来源,在现场调查的基础上,系统采集丰水期、平水期、枯水期沉陷区积水、地表河水和浅层地下水样进行测试分析,采用Piper三线图、Gibbs图和因子分析方法,对不同水体水化学特征及其影响因素进行讨论.结果表明:地表水水体总溶解性固体(TDS)质量浓度表现为枯水期丰水期平水期,浅层地下水表现为枯水期平水期丰水期,地表水TDS质量浓度明显高于浅层地下水.地表水中主要阴阳离子为Na~+、Cl~-和SO_4~(2-),水化学类型主要为SO_4~(2-)-Cl~--Na~+型;浅层地下水离子以HCO_3~-、Ca~(2+)和Mg~(2+)为主,表现为HCO_3~--Ca~(2+)-Mg~(2+)型.结合Gibbs图和因子分析可知,地表水受蒸发作用、地表径流以及采煤活动等因素影响,浅层地下水在一定程度上体现出大气降水和地表水补给的特点,受岩石风化作用影响较为明显.  相似文献   

18.
Dew samples were collected between October 2007 and February 2008 from a suburban site in Agra. pH, conductivity, major inorganic ions (F?, Cl?, NO 3 ? , SO 4 2? , Na+, K+, Ca2+, Mg2+, and NH 4 + ), and some trace metals (Cr, Sn, Zn, Pb, Cd, Ni, Mn, Fe, Si, Al, V, and Cu) were determined to study the chemistry of dew water. The mean pH was 7.3, and the samples exhibited high ionic concentrations. Dew chemistry suggested both natural and anthropogenic influences, with acidity being neutralized by atmospheric ammonia and soil constituents. Ion deposition flux varied from 0.25 to 3.0?neq?m?2?s?1, with maximum values for Ca2+ followed by NH 4 + , Mg2+, SO 4 2? , Cl?, NO 3 ? , Na+, K+, and F?. Concentrations of trace metals varied from 0.13 to 48?μg?l?1 with maximum concentrations of Si and minimum concentration of Cd. Correlation analysis suggested their contributions from both crustal and anthropogenic sources.  相似文献   

19.
ABSTRACT

Five-year monitoring of physicochemical parameters was performed with two campaigns in low and high water periods of the Lower Soummam catchment. Data from 18 wells were processed by multivariate statistical tools in order to identify the principal factors influencing groundwater chemistry. Two matrices of 14 and 8 physicochemical parameters with 18 groundwater samples collected in wells were obtained. The correlation matrix showed strong associations between nine variables: K+, Ca2+, Na+, SO42?, Cl?, Mg2+, NO2?, Zn2+ and Sr2+. Principal component analysis and factor analysis showed that the cumulated variance of high and low water periods was of 83.19% and 78.55%, respectively. The variables assigned to the mineralization effect or to pollution indicators were presented by the factor analysis. The bivariate plots confirmed a mineralization model, ascribed to dissolution of geological materials, and to high levels of saline contamination attributed to leakages from sanitary systems. They also showed an increase “upstream to downstream” of the mineralization, visualization of temporal variations, and a dilution process identification of the natural mineralization during the recharge of the aquifer.
EDITOR D. Koutsoyiannis; ASSOCIATE EDITOR X. Chen  相似文献   

20.
This study uses stable isotopes and major ions to examine the seasonal evolution of penitentes on the surface of Tapado Glacier, in the Norte Chico region of the Chilean Andes. A snow pit was sampled in November 2011, and penitentes were sampled during the summer (December 2011 and January 2012). The major ion load of the winter snowpack is dominated by Ca2+ (60%), SO42? (16%) and NO3? (13%), and there is little influence from marine air masses at the site, with most SO42?, Mg2+, Ca2+ and Na+, derived from non‐sea salt sources. During the early ablation season we observe increases in stable isotope ratios and major ion concentrations (particularly lithic ions Na+, Mg2+ and Ca2+) in the upper reaches of penitentes, which is attributed to sublimation and the aeolian deposition of dust particles. In the late‐summer, melt replaces sublimation as the dominant ablation process and results in smoothing of the stable isotope profile and the elution of major ions within the penitente snow and ice matrix. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

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