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| Author | Qi, H.; Ma, C.; He, Z.; Hu, X.; Gao, L. | ||||
| Title | Lithium and its isotopes as tracers of groundwater salinization: A study in the southern coastal plain of Laizhou Bay, China | Type | Journal Article | ||
| Year | 2019 | Publication | The Science of the Total Environment | Abbreviated Journal | Sci Total Environ |
Volume  |
650 | Issue | Pt 1 | Pages | 878-890 |
| Keywords | Brine and seawater intrusion; Groundwater salinization; Hydrochemistry; Lithium isotope; Southern coastal plain of Laizhou Bay | ||||
| Abstract | In the southern coastal plain of Laizhou Bay, due to intensive exploitation of groundwater since the early 1970s, the shallow aquifer has been severely influenced by saltwater intrusion, which causes the extraction to shift from shallow to deeper aquifer changing the hydrogeological condition greatly. This study was conducted to investigate the groundwater salinization using hydrochemistry and H, O and Li isotope data. Dissolved Li shows a linear correlation with Cl and Br in seawater, brine and saline groundwater indicating the marine Li source, whereas the enrichment of Li in surface water, brackish and fresh groundwater is impacted by dissolution of silicate minerals. The analyses of hydrochemistry and isotopes (H, O and Li) indicate that brine originated from seawater evaporation, followed by mixing processes and some water-rock interactions; shallow saline groundwater originated from brine diluted with seawater and fresh groundwater; deep saline groundwater originated from seawater intrusion. The negative correlation of δ(7)Li and Li/Na in surface water, brackish and fresh groundwater is contrary to the general conclusion, indicating the slow weathering of silicate minerals and hydraulic interaction between surface water and shallow groundwater in this area. The analyses of hydrochemistry and isotopes (Li, H and O) can well identify the salinity sources and isotope fractionation in groundwater flow and mixing, especially groundwater with high TDS. As both mixing with saltwater and isotope fractionation can explain the combination of high δ(7)Li and low TDS in brackish groundwater, isotope fractionation may limit their use in recognizing salinity sources of groundwater with low TDS. | ||||
| Address | School of Environmental Studies, China University of Geosciences, Wuhan 430074, China | ||||
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| Language | English | Summary Language | Original Title | ||
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| ISSN | 0048-9697 | ISBN | Medium | ||
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| Notes | PMID:30308862 | Approved | no | ||
| Call Number | THL @ christoph.kuells @ | Serial | 184 | ||
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| Author | Kreynsa*, P.; Genga, X.; Michaela, H.A. | ||||
| Title | The influence of connected heterogeneity on groundwater flow and salinity distributions in coastal volcanic aquifers | Type | Journal Article | ||
| Year | 2020 | Publication | J.Hydrol. | Abbreviated Journal | |
| Volume |
586 | Issue | Pages | 124863 | |
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| Notes | Approved | no | |||
| Call Number | CUT @ phaedon.kyriakidis @ Kreynsa2020 | Serial | 138 | ||
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| Author | Petelet-Giraud, E.; Négrel, P.; Aunay, B.; Ladouche, B.; Bailly-Comte, V.; Guerrot, C.; Flehoc, C.; Pezard, P.; Lofi, J.; Dörfliger, N. | ||||
| Title | Coastal groundwater salinization: Focus on the vertical variability in a multi-layered aquifer through a multi-isotope fingerprinting (Roussillon Basin, France) | Type | Journal Article | ||
| Year | 2016 | Publication | Science of The Total Environment | Abbreviated Journal | |
| Volume |
566-567 | Issue | Pages | 398-415 | |
| Keywords | Groundwater salinization, Coastal aquifer, Roussillon Basin, Isotopes, Westbay System, Barcarès and Canet sites | ||||
| Abstract | The Roussillon sedimentary Basin (South France) is a complex multi-layered aquifer, close to the Mediterranean Sea facing seasonally increases of water abstraction and salinization issues. We report geochemical and isotopic vertical variability in this aquifer using groundwater sampled with a Westbay System® at two coastal monitoring sites: Barcarès and Canet. The Westbay sampling allows pointing out and explaining the variation of water quality along vertical profiles, both in productive layers and in the less permeable ones where most of the chemical processes are susceptible to take place. The aquifer layers are not equally impacted by salinization, with electrical conductivity ranging from 460 to 43,000μS·cm−1. The δ2H–δ18O signatures show mixing between seawater and freshwater components with long water residence time as evidenced by the lack of contribution from modern water using 3H, 14C and CFCs/SF6. S(SO4) isotopes also evidence seawater contribution but some signatures can be related to oxidation of pyrite and/or organically bounded S. In the upper layers 87Sr/86Sr ratios are close to that of seawater and then increase with depth, reflecting water–rock interaction with argillaceous formations while punctual low values reflect interaction with carbonate. Boron isotopes highlight secondary processes such as adsorption/desorption onto clays in addition to mixings. At the Barcarès site (120m deep), the high salinity in some layers appear to be related neither to present day seawater intrusion, nor to Salses-Leucate lagoonwater intrusion. Groundwater chemical composition thus highlights binary mixing between fresh groundwater and inherited salty water together with cation exchange processes, water–rock interactions and, locally, sedimentary organic matter mineralisation probably enhanced by pyrite oxidation. Finally, combining the results of this study and those of Caballero and Ladouche (2015), we discuss the possible future evolution of this aquifer system under global change, as well as the potential management strategies needed to preserve quantitatively and qualitatively this water resource. | ||||
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| ISSN | 0048-9697 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Peteletgiraud2016398 | Serial | 181 | ||
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| Author | Kurunc, A.; Ersahin, S.; Sonmez, N.K.; Kaman, H.; Uz, I.; Uz, B.Y.; Aslan, G.E. | ||||
| Title | Seasonal changes of spatial variation of some groundwater quality variables in a large irrigated coastal Mediterranean region of Turkey | Type | Journal Article | ||
| Year | 2016 | Publication | Science of the Total Environment | Abbreviated Journal | |
| Volume |
554 | Issue | Pages | 53-63 | |
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| Abstract | Soil and groundwater degradations have taken considerable attention, recently. We studied spatial and temporal variations of groundwater table depth and contours, and groundwater pH, electrical conductivity (EC), and nitrate (NO3) content in a large irrigated area in Western Mediterranean region of Turkey. These variables were monitored during 2009 and 2010 in previously constructed 220 monitoring wells. We analyzed the data by geostatistical techniques and GIS. Spatial variation of groundwater table depth (GTD) and groundwater table contours (GTC) remained similar across the four sampling campaigns. The values for groundwater NO3 content, EC, and pH values ranged from 0.01 to 454.1 g L−1 , 0.06 to 46.0 dS m−1 and 6.53–9.91, respectively. Greatest geostatistical range (16,964 m) occurred for GTC and minimum (960 m) for groundwater EC. Groundwater NO3 concentrations varied both spatially and temporally. Temporal changes in spatial pattern of NO3 indicated that land use and farming practices influenced spatial and temporal variation of groundwater NO3. Several hot spots occurred for groundwater NO3 content and EC. These localities should be monitored more frequently and land management practices should be adjusted to avoid soil and groundwater degradation. The results may have important implications for areas with similar soil, land use, and climate conditions across the Mediterranean region. |
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| Publisher | Elsevier | Place of Publication | Editor | ||
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| ISSN | 0048-9697 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | THL @ luqianxue.zhang @ Kurunc2016 | Serial | 45 | ||
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| Author | Llopis-Albert, C.; Merigó, J.M.; Xu, Y. | ||||
| Title | A coupled stochastic inverse/sharp interface seawater intrusion approach for coastal aquifers under groundwater parameter uncertainty | Type | Journal Article | ||
| Year | 2016 | Publication | Journal of Hydrology | Abbreviated Journal | |
| Volume |
540 | Issue | Pages | 774-783 | |
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| Abstract | This paper presents an alternative approach to deal with seawater intrusion problems, that overcomes some of the limitations of previous works, by coupling the well-known SWI2 package for MODFLOW with a stochastic inverse model named GC method. On the one hand, the SWI2 allows a vertically integrated variable-density groundwater flow and seawater intrusion in coastal multi-aquifer systems, and a reduction in number of required model cells and the elimination of the need to solve the advective-dispersive transport equation, which leads to substantial model run-time savings. On the other hand, the GC method allows dealing with groundwater parameter uncertainty by constraining stochastic simulations to flow and mass transport data (i.e., hydraulic conductivity, freshwater heads, saltwater concentrations and travel times) and also to secondary information obtained from expert judgment or geophysical surveys, thus reducing uncertainty and increasing reliability in meeting the environmental standards. The methodology has been successfully applied to a transient movement of the freshwater-seawater interface in response to changing freshwater inflow in a two-aquifer coastal aquifer system, where an uncertainty assessment has been carried out by means of Monte Carlo simulation techniques. The approach also allows partially overcoming the neglected diffusion and dispersion processes after the conditioning process since the uncertainty is reduced and results are closer to available data. | ||||
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| ISSN | 0022-1694 | ISBN | Medium | ||
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| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Llopis-Albert2016 | Serial | 30 | ||
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