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Author | Kim, Y.; Lee, K.-S.; Koh, D.-C.; Lee, D.-H.; Lee, S.-G.; Park, W.-B.; Koh, G.-W.; Woo, N.-C. | ||||
Title | Hydrogeochemical and isotopic evidence of groundwater salinization in a coastal aquifer: a case study in Jeju volcanic island, Korea | Type | Journal Article | ||
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2003 | Publication | Journal of Hydrology | Abbreviated Journal | |
Volume | 270 | Issue | 3 | Pages | 282-294 |
Keywords | Jeju volcanic island, Coastal aquifer, Groundwater salinization, Hydrogeochemistry, Environmental isotopes, Mixing process | ||||
Abstract | In order to identify the origin of saline groundwater in the eastern part of Jeju volcanic island, Korea, a hydrogeochemical and isotopic study has been carried out for 18 observation wells located in east and southeast coastal regions. The total dissolved solid contents of groundwaters are highly variable (77–21,782mg/l). Oxygen, hydrogen, sulfur, and strontium isotopic data clearly show that the saline water results from mixing of groundwater with seawater. Strontium isotopic compositions and Br/Cl and I/Cl ratios strongly suggest that the source of salinity is modern seawater intrusion. Hydrogeochemical characteristics based on bivariate diagrams of major and minor ions show that changes in the chemical composition of groundwater are mainly controlled by the salinization process followed by cation-exchange reactions. The highly permeable aquifers at the east coastal region are characterized by low hydraulic gradient and discharge rate and high hydraulic conductivity as compared with other regions. These properties enhance the salinization of groundwater observed in the study area. Based on the Cl, Br, and δ18O data, seawater was determined to have intruded inland some 2.5km from the coastline. Considering the poor correlation of sampling depth and Cl concentrations observed, the position of seawater-freshwater interface is not uniformly distributed in the study area, due to heterogeneities of the basaltic aquifers. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0022-1694 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ christoph.kuells @ Kim2003282 | Serial | 172 | ||
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Author | El Mandour, A.; El Yaouti, F.; Fakir, Y.; Zarhloule, Y.; Benavente, J. | ||||
Title | Evolution of groundwater salinity in the unconfined aquifer of Bou-Areg, Northeastern Mediterranean coast, Morocco | Type | Journal Article | ||
Year ![]() |
2007 | Publication | Environmental Geology | Abbreviated Journal | |
Volume | 54 | Issue | 3 | Pages | 491-503 |
Keywords | Unconfined aquifer, Groundwater salinity, Seawater intrusion, Nitrate pollution, Lagoon, Morocco Bou-Areg | ||||
Abstract | The Bou-Areg plain in the Mediterranean coast at the North-eastern of Morocco is characterized by a semiarid climate. The aquifer consists of two sedimentary formations of Plio-quaternary age: the upper formation of fine silts and the lower one of coarse silts with sand and gravels. The aquifer is underlain by marly bedrock of Miocene age that dips toward the coastal lagoon of Bou-Areg. The hydrodynamic characteristics vary between 10–4 and 10–3 m/s; and transmissivities range between 10–4 and 10–1 m2 /s. The general direction of flow is SW to NE, toward the lagoon. The aquifer is crossed by the river Selouane, which also ends in the lagoon. The groundwater is characterized by a high salinity that can reach 7.5 g/l. The highest values are observed in the upstream and in the downstream sectors of the aquifer. The temporal evolution of the physicochemical parameters depends on the climatic conditions and piezometric variations. The analysis of the spatio-temporal distribution of the physico-chemical parameters suggests different sources of groundwater salinization: the seawater intrusion, the influence of marly gypsum-bearing terrains, and the influence of anthropogenic products as the agricultural fertilizers, which cause great nitrate concentrations that vary between 80 and 140 mg/l. |
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Publisher | Springer | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0943-0105 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ luqianxue.zhang @ ElMandour2008 | Serial | 44 | ||
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Author | Di Lorenzo, T.; Galassi, D.M.P. | ||||
Title | Agricultural impact on Mediterranean alluvial aquifers: do groundwater communities respond? | Type | Journal Article | ||
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2013 | Publication | Fundamental and Applied Limnology/Archiv für Hydrobiologie | Abbreviated Journal | |
Volume | 182 | Issue | 4 | Pages | 271-282 |
Keywords | alluvial aquifers, groundwater, stygobiont, nitrate, overexploitation | ||||
Abstract | In Mediterranean countries agricultural development heavily depends on groundwater availability due to arid and semi-arid climate and poor surface-water resources. Agriculture represents one of the most relevant pressures which generate impacts in alluvial aquifers by means of fertilizers and pesticides usage and groundwater overexploitation. Until now, very few studies have addressed the ecological response of groundwater fauna to groundwater contamination and overexploitation due to agricultural practices. We investigated a Mediterranean alluvial aquifer heavily affected by nitrates contamination and groundwater abstraction stress due to crop irrigation. The aim of this study was to evaluate the sensitivity of groundwater communities to (a) groundwater nitrate contamination, (b) groundwater abstraction due to irrigation practices, and (c) saltwater intrusion. The present work suggests that nitrate concentration lower than 150 mg l –1 is not an immediate threat to groundwater biodiversity in alluvial aquifers. This conclusion must be carefully considered in the light of the total lack of knowledge of the effects of long-term nitrate pollution on the groundwater biota. Moreover, local extinctions of less tolerant species, prior to monitoring, cannot be ruled out. Conversely, species abundances in ground water are affected by groundwater withdrawal, but species richness may be less sensitive. This result is attributable to the disappearance of saturated microhabitats and to the depletion of fine unconsolidated sediments, reducing the surface available to bacterial biofilm, which represent the trophic resource for several groundwater invertebrates and where the main aquifer self-purification processes, such as denitrification, take place. Saltwater intrusion seems not to affect groundwater species at the values measured in this coastal aquifer. |
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Publisher | E. Schweizerbart'sche Verlagsbuchhandlung | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1863-9135 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ luqianxue.zhang @ DiLorenzo2013 | Serial | 43 | ||
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Author | Han, D.M.; Song, X.F.; Currell, M.J.; Yang, J.L.; Xiao, G.Q. | ||||
Title | Chemical and isotopic constraints on evolution of groundwater salinization in the coastal plain aquifer of Laizhou Bay, China | Type | Journal Article | ||
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2014 | Publication | Journal of Hydrology | Abbreviated Journal | |
Volume | 508 | Issue | Pages | 12-27 | |
Keywords | Laizhou Bay, Coastal aquifers, Groundwater hydrochemistry, Stable isotopes, Saltwater intrusion | ||||
Abstract | Summary A hydrochemical-isotopic investigation of the Laizhou Bay Quaternary aquifer in north China provides new insights into the hydrodynamic and geochemical relationships between freshwater, seawater and brine at different depths in coastal sediments. Saltwater intrusion mainly occurs due to two cones of depression caused by concentrated exploitation of fresh groundwater in the south, and brine water for salt production in the north. Groundwater is characterized by hydrochemical zonation of water types (ranging from Ca–HCO3 to Na–Cl) from south to north, controlled by migration and mixing of saline water bodies with the regional groundwater. The strong adherence of the majority of ion/Cl ratios to mixing lines between freshwater and saline water end-members (brine or seawater) indicates the importance of mixing under natural and/or anthropogenic influences. Examination of the groundwater stable isotope δ18O and δ2H values (between −9.5‰ and −3.0‰ and −75‰ and −40‰, respectively) and chloride contents (∼2 to 1000meq/L) of the groundwater indicate that the saline end-member is brine rather than seawater, and most groundwater samples plot on mixing trajectories between fresh groundwater (δ18O of between −6.0‰ and −9.0‰; Cl<5meq/L) and sampled brines (δ18O of approximately −3.0‰ and Cl>1000meq/L). Locally elevated Na/Cl ratios likely result from ion exchange in areas of long-term freshening. The brines, with radiocarbon activities of ∼30 to 60 pMC likely formed during the Holocene as a result of the sequence of transgression-regression and evaporation; while deep, fresh groundwater with depleted stable isotopic values (δ18O=−9.7‰ and δ2H=−71‰) and low radiocarbon activity (<20 pMC) was probably recharged during a cooler period in the late Pleistocene, as is common throughout northern China. An increase in the salinity and tritium concentration in some shallow groundwater sampled in the 1990s and re-sampled here indicates that intensive brine extraction has locally resulted in rapid mixing of young, fresh groundwater and saline brine. The δ18O and δ2H values of brines (∼−3.0‰ and −35‰) are much lower than that of modern seawater, which could be explained by 1) mixing of original (δ18O enriched) brine that was more saline than presently observed, with fresh groundwater recharged by precipitation and/or 2) dilution of the palaeo-seawater with continental runoff prior to and/or during brine formation. The first mechanism is supported by relatively high Br/Cl molar ratios (1.7×10−3–2.5×10−3) in brine water compared with ∼1.5×10−3 in seawater, which could indicate that the brines originally reached halite saturation and were subsequently diluted with fresher groundwater over the long-term. Decreasing 14C activities with increasing sampling depth and increasing proximity to the coastline indicate that the south coastal aquifer in Laizhou Bay is dominated by regional lateral flow, on millennial timescales. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Summary Language | Original Title | |||
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Series Volume | Series Issue | Edition | |||
ISSN | 0022-1694 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ christoph.kuells @ Han201412 | Serial | 174 | ||
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Author | Cary, L.; Petelet-Giraud, E.; Bertrand, G.; Kloppmann, W.; Aquilina, L.; Martins, V.; Hirata, R.; Montenegro, S.M.G.L.; Pauwels, H.; Chatton, E.; Franzen, Melissa; Aurouet, A.; Lasseur, E.; Picot-Colbeaux, G.; Guerrot, C.; Fléhoc, C.; Labasque, T.; Santos, Jeane Glaucia; Paiva, Anderson L.R.; Braibant, G.; Pierre, D. | ||||
Title | Origins and processes of groundwater salinization in the urban coastal aquifers of Recife (Pernambuco, Brazil): a multi-isotope approach | Type | Journal Article | ||
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2015 | Publication | Science of the Total Environment | Abbreviated Journal | |
Volume | 530-531 | Issue | Pages | 411-429 | |
Keywords | Salinization origins; Salinization processes; Groundwater; Coastal aquifer; Strontium isotopes; Boron isotopes; Recife; Brazil | ||||
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Publisher | Elsevier | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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Series Volume | Series Issue | Edition | |||
ISSN | ISBN | Medium | |||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ christoph.kuells @ cary:hal-01161949 | Serial | 85 | ||
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