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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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| 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 @ Llopis-Albert2016 | Serial | 30 | ||
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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 | ||
| Language | Summary Language | Original Title | |||
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| Series Volume | Series Issue | Edition | |||
| ISSN |
0048-9697 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ luqianxue.zhang @ Kurunc2016 | Serial | 45 | ||
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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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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
0048-9697 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Peteletgiraud2016398 | Serial | 181 | ||
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| Author | Siarkos, I.; Latinopoulos, P. | ||||
| Title | Modeling seawater intrusion in overexploited aquifers in the absence of sufficient data: application to the aquifer of Nea Moudania, northern Greece | Type | Journal Article | ||
| Year | 2016 | Publication | Hydrogeology Journal | Abbreviated Journal | Hydrogeology J. |
| Volume | 24 | Issue | Pages | 2123–2141 | |
| Keywords | Groundwater flow, Seawater intrusion, Numerical modeling, Greece, Sensitivity analysis | ||||
| Abstract | In many coastal areas, overexploitation of groundwater resources has led both to the quantitative degradation of local aquifers and the deterioration of groundwater quality due to seawater intrusion. To investigate the behavior of coastal aquifers under these conditions, numerical modeling is usually implemented; however, the proper implementation of numerical models requires a large amount of data, which are often not available due to the time-consuming and costly process of obtaining them. In the present study, the investigation of the behavior of coastal aquifers under the lack of adequate data is attempted by developing a methodological framework consisting of a series of numerical simulations: a steady-state, a false-transient and a transient simulation. The sequence and the connection between these simulations constitute the backbone of the whole procedure aimed at adjusting the various model parameters, as well as obtaining the initial conditions for the transient simulation. The validity of the proposed methodology is tested through evaluation of the model calibration procedure and the estimation of the simulation errors (mean error, mean absolute error, root mean square error, mean relative error) using the case of Nea Moudania basin, northern Greece. Furthermore, a sensitivity analysis is performed in order to minimize the error estimates and thus to maximize the reliability of the models. The results of the whole procedure affirm the proper implementation of the developed methodology under specific conditions and assumptions due to the lack of sufficient data, while they give a clear picture of the aquifer’s quantitative and qualitative status. |
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| Address | Ilias Siarkos: isiarkos@civil.auth.gr; Pericles Latinopoulos latin@civil.auth.gr | ||||
| Corporate Author | School of Civil Engineering, Aristotle University of Thessaloniki, GR54124 Thessaloniki, Greece | Thesis | |||
| Publisher | IAH | Place of Publication | Editor | Springer | |
| Language | English | Summary Language | Original Title | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
1431-2174 | ISBN | Medium | ||
| Area | Hydrogeology; groundwater modelling, sea water intrusion | Expedition | Conference | ||
| Notes | Approved | yes | |||
| Call Number | MGRE @ redha.menani @ | Serial | 52 | ||
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