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Author | Darwish, T.; Atallah, T.; Francis, R.; Saab, C.; Jomaa, I.; Shaaban, A.; Sakka, H.; Zdruli, P. | ||||
Title | Observations on soil and groundwater contamination with nitrate: A case study from Lebanon-East Mediterranean | Type | Journal Article | ||
Year | 2011 | Publication | Agricultural Water Management | Abbreviated Journal | |
Volume | 99 | Issue | 1 | Pages | 74-84 |
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Abstract | The impact of agricultural practices on soil–groundwater quality in the sub-humid Bekaa plain of Lebanon-East Mediterranean was monitored in four fields (F) between July 2007 and July 2009. These were occupied by continuous mint (F1), summer potato/wheat/potato (F2), lettuce/lettuce/potato/wheat/summer potato (F3) and table grapes (F4). N input calculated on a two-year basis, was in the following ascending order F4, F2, F3 and F1. Soil samples, analyzed down to 200 cm depth, showed high nitrate and chloride concentrations at the end of the 2007 and 2008 seasons. Soil chloride and nitrate peaks recorded in October 2007 and 2008 disappeared below 200 cm overwinter. The calculated N biannual discharge ranged from 130 (F4), to 516 (F2), to 778 (F1), to 879 kg ha−1 (F3). Groundwater quality was studied in 21 wells distributed along a sequence stretching from the Litani River to the eastern water dividing line. Based on the nitrate concentrations, the well located at the top of the water dividing line was the only one suitable for drinking purposes. Eight wells were mildly contaminated, therefore suitable for irrigation purposes except for sensitive crops. Twelve wells, positioned in the plain, showed a nitrate level exceeding 200 mg L−1. Protecting the soil and groundwater quality is a top priority to maintain the ecological and agricultural functions of water. | ||||
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Corporate Author | Thesis | ||||
Publisher | Elsevier | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0378-3774 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ luqianxue.zhang @ Darwish2011 | Serial | 48 | ||
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Author | Jesús Carrera, Juan J. Hidalgo, Luit J. Slooten, Enric Vázquez-Suñé | ||||
Title | Computational and conceptual issues in the calibration of seawater intrusion models | Type | Journal Article | ||
Year | 2010 | Publication | Hydrogeology Journal | Abbreviated Journal | |
Volume | 18 | Issue | Pages | 131-145 | |
Keywords | Coastal aquifers; Inverse modelling; Numerical modeling | ||||
Abstract | The inverse problem of seawater intrusion(SWI) is reviewed. It represents a challenge because of both conceptual and computational difficulties and because coastal aquifer models display many singularities:(1) head measurements need to be complemented with density information; (2) salinity concentration data are very sensitive to flow within the borehole. Data problems can be reduced by incorporating the measurement process within model calibration; (3) SWI models are extremely sensitive to aquifer bottom topography; (4) the initial conditions may be far from steady state and depend on the location and type of sea-aquifer connection. Problems with aquifer geometry and initial conditions can be addressed by parameterization, which allows for modification during inversion. The four sets of difficulties can be partly overcome by using tidal response and electrical conductivity data, which are highly informative and provide extensive coverage. Still, SWI inversion is extremely demanding from a computation point of view. Computational improvements are discussed. |
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Address | J. Carrera : J. J. Hidalgo ()) : L. J. Slooten : E. Vázquez-Suñé, Spain e-mail: juan.hidalgo@upc.edu | ||||
Corporate Author | Institute of Environmental Ass Institute of Environmental Assessment and Water Research (IDAEA), Spanish National Research Council (CSIC), Jordi Girona 18, 08034 Barcelona, e-mail: juan.hidalgo@upc.edu | 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 (online: 1435-0157) | ISBN | Medium | ||
Area | 'Hydrogeology'; 'groundwater modelling' | Expedition | Conference | ||
Notes | Approved | yes | |||
Call Number | MGRE @ redha.menani @ | Serial | 51 | ||
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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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Author | Schmittner, K.-E.; Giresse, P. | ||||
Title | The impact of atmospheric sodium on erodibility of clay in a coastal Mediterranean region | Type | Journal Article | ||
Year | 1999 | Publication | Environmental Geology | Abbreviated Journal | |
Volume | 37 | Issue | 3 | Pages | 195-206 |
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Abstract | Heavy rainfalls, between 25 and 100 mm·h–1, were simulated on Pliocene/Quaternary sediments. To reproduce the heterogeneity of natural environments, 231 small plots of various sizes (between 2.5 and 3.5 m2; mean: about 3 m2) were used. The duration of all simulations was 1 h. We used water that had been collected during natural rainfall. The concentration of clay particles in the sheet wash depended upon the concentration of dissolved sodium in the wash (for about 42%) and of the sheet wash quantity (for about 37%). Under natural water conditions colloidal matter, like clay minerals, is charged negatively and therefore is destabilized by metal cations such as in the case of Na+. Results suggest that relatively higher concentrations of montmorrillonite were related to higher concentrations of sodium as opposed to illite and kaolinite. Microflakes of up to 25 μ were observed to vary between face-to-edge and face-to-face modes (competition between protons and other cations). The concentration of dissolved sodium (Na+) in the runoff water depends on water and sodium balances such as atmospheric input, infiltration, evaporation and surface water runoff. The reduction of vegetation cover increases the amount of salt and amorphous matter in/on the topsoil between heavy rainfall generations. The best predictor to explain montmorillonite, illite and kaolinite in % of mineral clay-sized matter in the surface water runoff (sheet wash) is the percentage of each clay mineral in the topsoil. As opposed to illite and kaolinite, more sheet wash indicate for montmorillonite relatively higher concentrations in the wash. The results of model simulations were confirmed on different field plots of about 1 ha and small catchments during natural heavy rainfall events. Models can also be used to understand and to better simulate sheet, rill and gully erosion, micropedimentation; and pedimentation. | ||||
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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 | 1432-0495 | ISBN | Medium | ||
Area | Expedition | Conference | |||
Notes | Approved | no | |||
Call Number | THL @ luqianxue.zhang @ Schmittner1999 | Serial | 53 | ||
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Author | Morales-Baquero, R.; Pulido-Villena, E.; Reche, I. | ||||
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 |
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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. | ||||
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Corporate Author | Thesis | ||||
Publisher | Taylor & Francis | Place of Publication | Editor | ||
Language | Summary Language | Original Title | |||
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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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