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Author (up) Mongelli, G.; Monni, S.; Oggiano, G.; Paternoster, M.; Sinisi, R. url  doi
openurl 
  Title Tracing groundwater salinization processes in coastal aquifers: a hydrogeochemical and isotopic approach in the Na-Cl brackish waters of northwestern Sardinia, Italy Type Journal Article
  Year 2013 Publication Hydrology and Earth System Sciences Abbreviated Journal  
  Volume 17 Issue 7 Pages 2917-2928  
  Keywords salinization, isotopes, Sardinia  
  Abstract Throughout the Mediterranean, salinization threatens water quality, especially in coastal areas. This salinization is the result of concomitant processes related to both seawater intrusion and water–rock interaction, which in some cases are virtually indistinguishable. In the Nurra region of northwestern Sardinia, recent salinization related to marine water intrusion has been caused by aquifer exploitation. However, the geology of this region records a long history from the Palaeozoic to the Quaternary, and is structurally complex and comprises a wide variety of lithologies, including Triassic evaporites. Determining the origin of the saline component of the Jurassic and Triassic aquifers in the Nurra region may provide a useful and more general model for salinization processes in the Mediterranean area, where the occurrence of evaporitic rocks in coastal aquifers is a common feature. In addition, due to intensive human activity and recent climatic change, the Nurra has become vulnerable to desertification and, in common with other Mediterranean islands, surface water resources periodically suffer from severe shortages. With this in mind, we report new data regarding brackish and surface waters (outcrop and lake samples) of the Na-Cl type from the Nurra region, including major ions and selected trace elements (B, Br, I, and Sr), in addition to isotopic data including δ18O, δD in water, and δ34S and δ18O in dissolved SO4. To identify the origin of the salinity more precisely, we also analysed the mineralogical and isotopic composition of Triassic evaporites. The brackish waters have Cl contents of up to 2025 mg L−1 , and the ratios between dissolved ions and Cl, with the exception of the Br / Cl ratio, are not those expected on the basis of simple mixing between rainwater and seawater. The δ18O and δD data indicate that most of the waters fall between the regional meteoric water line and the global meteoric water line, supporting the conclusion that they are meteoric in origin. A significant consequence of the meteoric origin of the Na-Cl-type water studied here is that the Br / Cl ratio, extensively used to assess the origin of salinity in fresh water, should be used with care in carbonate aquifers that are near the coast. Overall, δ34S and δ18O levels in dissolved SO4 suggest that water–rock interaction is responsible for the Na-Cl brackish composition of the water hosted by the Jurassic and Triassic aquifers of the Nurra, and this is consistent with the geology and lithological features of the study area. Evaporite dissolution may also explain the high Cl content, as halite was detected within the gypsum deposits. Finally, these Na-Cl brackish waters are undersaturated with respect to the more soluble salts, implying that in a climate evolving toward semi-arid conditions, the salinization process could intensify dramatically in the near future.  
  Address  
  Corporate Author Thesis  
  Publisher Copernicus Place of Publication Editor  
  Language en Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ hess-17-2917-2013 Serial 79  
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Author (up) Morales-Baquero, R.; Pulido-Villena, E.; Reche, I. url  doi
openurl 
  Title Chemical signature of Saharan dust on dry and wet atmospheric deposition in the south-western Mediterranean region Type Journal Article
  Year 2013 Publication Tellus B: Chemical and Physical Meteorology Abbreviated Journal  
  Volume 65 Issue 1 Pages 18720  
  Keywords  
  Abstract We studied if the presence of Saharan dust intrusions and the rains modify the chemical signature of the wet and dry deposition in the southern Iberian Peninsula. We have sorted the 109 sampling weeks by the presence (rainy weeks) or absence (dry weeks) of rain and by the occurrence or not of Saharan dust intrusions. Dry deposition dominated the delivery of particulate material (PM), total phosphorus (TP), soluble reactive phosphorus (SRP), Ca2+, Mg2+ and K+, whereas wet deposition dominated the delivery of Na+, total nitrogen, and . In the dry weeks, the presence of Saharan dust intrusions lead to higher inputs of PM, TP, SRP, Ca2+, Mg2+ and K+ in the dry deposition. Conversely, in the rainy weeks, there were no differences in mean values of dry deposition irrespective of the occurrence of Saharan dust intrusions. Nevertheless, in the presence of Saharan intrusions and some rain, the weekly collection of PM, TP and Ca2+ in dry deposition were significantly higher and increased as rainfall was lower. By contrast, the ions Cl– and Na+ in wet deposition were higher in absence of Saharan dust intrusion and increased as rainfall increased.  
  Address  
  Corporate Author Thesis  
  Publisher Taylor & Francis Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ luqianxue.zhang @ doi:10.3402/tellusb.v65i0.18720 Serial 54  
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Author (up) Rina, K.; Datta, P.S.; Singh, C.K.; Mukherjee, S. url  openurl
  Title Isotopes and ion chemistry to identify salinization of coastal aquifers of Sabarmati River Basin Type Journal Article
  Year 2013 Publication Abbreviated Journal Current Science  
  Volume 104 Issue 3 Pages 335-344  
  Keywords  
  Abstract The lower reaches of the Sabarmati River Basin in Gujarat have intense agricultural and industrial activities and this part is affected by problems of groundwater salinity. Here we attempt to assess the processes governing the causes of groundwater salinity in the coastal alluvial aquifer, employing δ18O and δD isotopes in integration with ionic ratio. The different hydrochemical facies such Na–Mg–HCO3–Cl, Na–Cl–SO4, Na–Mg–Cl–HCO3–SO4 and Na–Cl of groundwater show the occurrence of complex geochemical phenomenon in the study area. Ionic ratio (such as Mg2+/Ca2+, Na+/Cl−, SO24/Cl-, K+/Cl−) and isotopic composition (δ18O and δD) of groundwater indicate that while in coastal areas seawater intrusion is taking place, in inland areas various anthropogenic activities and overexploitation have induced salinity in groundwater. Over-pumping of groundwater has also induced lateral intermixing of highly saline water in the vicinity of coastal areas with relatively fresh/low saline groundwater along specific flow pathways.  
  Address  
  Corporate Author Thesis  
  Publisher Current Science Association Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0011-3891 ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ christoph.kuells @ Serial 190  
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Author (up) Zghibi, A.; Zouhri, L.; Tarhouni, J.; Kouzana, L. url  openurl
  Title Groundwater mineralisation processes in Mediterranean semi-arid systems (Cap-Bon, North east of Tunisia): hydrogeological and geochemical approaches Type Journal Article
  Year 2013 Publication Hydrological Processes Abbreviated Journal  
  Volume 27 Issue 22 Pages 3227-3239  
  Keywords  
  Abstract  
  Address  
  Corporate Author Thesis  
  Publisher Wiley Online Library Place of Publication Editor  
  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference  
  Notes Approved no  
  Call Number THL @ luqianxue.zhang @ zghibi2013groundwater Serial 73  
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