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| Author | Alexakis, D.; Gotsis, D.; Giakoumakis, S. | ||||
| Title | Evaluation of soil salinization in a Mediterranean site (Agoulinitsa district—West Greece) | Type | Journal Article | ||
| Year | 2015 | Publication | Arabian Journal of Geosciences | Abbreviated Journal | |
| Volume | 8 | Issue | 3 | Pages | 1373-1383 |
Keywords  |
Agricultural soil . Soil quality . Soil salinization | ||||
| Abstract | Soil salinization is an environmental problem having significant impacts on the soil–water–plant system. This problem is more frequent in coastal areas due to seawater intrusion into the land. Assessing the soil salinization is a critical issue for the agricultural areas situated in the Mediterranean basin. This paper examines the deterioration of soil quality in the cultivated land of a Mediterranean site (Agoulinitsa district—West Greece). Soil samples were collected in both pre-irrigation and post-irrigation seasons. Electrical conductivity (EC), pH and the ions Br−, Ca2+, Cl−, F−, K+, Li+, Mg2+, Na+, NH4 +, NO2 −, NO3 −, PO4 3− and SO4 2− were determined by the 1:2 (soil/water ratio on weight basis) method. The salts which were present in both seasons in the soils of the area studied are KCl, MgCl2, NaCl, CaSO4 and K2SO4. The wide spatiotemporal variation of EC in the cultivated land in both seasons demonstrates that soil salinity is controlled mainly by seawater intrusion and anthropogenic factors such as the application of salt-rich water which is directly pumped from the drainage ditches. Seawater intrusion provides the affected soil with elevated contents of Ca2+, Cl−, K+, Mg2+, Na+ and SO4 2−. Classification of the soils by using criteria given by the literature is discussed. Practices to prevent, or at least ameliorate, salinization in the cultivated land of Agoulinitsa district are proposed. |
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| Corporate Author | Thesis | ||||
| Publisher | Springer | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1866-7511 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ luqianxue.zhang @ Alexakis2015 | Serial | 42 | ||
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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 | ||
| Year | 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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| Address | |||||
| Corporate Author | Thesis | ||||
| 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 | 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 | ||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | English | 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 | PMID:30308862 | Approved | no | ||
| Call Number | THL @ christoph.kuells @ | Serial | 184 | ||
| Permanent link to this record | |||||
| 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 | ||
| Permanent link to this record | |||||
| Author | Zhao, Q.; Su, X.; Kang, B.; Zhang, Y.; Wu, X.; Liu, M. | ||||
| Title | A hydrogeochemistry and multi-isotope (Sr, O, H, and C) study of groundwater salinity origin and hydrogeochemcial processes in the shallow confined aquifer of northern Yangtze River downstream coastal plain, China | Type | Journal Article | ||
| Year | 2017 | Publication | Applied Geochemistry | Abbreviated Journal | |
| Volume | 86 | Issue | Pages | 49-58 | |
| Keywords |
Coastal confined groundwater, Salinity, Hydrogeochemcial processes, Multiple environmental tracers | ||||
| Abstract | Economically developed coastal areas have a high water demand, and their groundwater resources can be threatened by salinization. Many methods and tracers have been used to discriminate the source of salinization because a single method does not yield reliable results. In this paper, the shallow confined coastal plain aquifer, north of the downstream Yangtze River in China, is used as a case study to investigate the origin of the salinity and the relevant geochemical processes for this aquifer. Multiple environmental tracers of major ions, minor ions (Br−, I−), and isotopes (18O, 2H, 13C, 87Sr, 3H, 14C) were used so as to provide reliable conclusions. The TDS distribution of the aquifer has an increasing trend, from below 500 mg/L in the inland areas to more than 20,000 mg/L around the southeast coastline. The water chemical type evolves from HCO3-Ca to Cl-Na as the TDS increases. The results suggest that the groundwater salinity is influenced by seawater intrusion. The seawater proportions in the groundwater samples range from 0.07% to 94.41% and show the same spatial distribution pattern as TDS. The 3H and 14C values show that the highest salinity was mainly caused by a seawater transgression around 6000a B.P. The aquifer is also affected by other hydrogeochemical processes: base exchange has enriched Ca2+ and depleted K+ and Na+, sulfate reduction has reduced the concentration of SO42− and enriched HCO3−, and iodine-rich organic matter decomposition has enriched the concentration of I−. The iodine enrichment also suggests paleo-seawater intrusion. In addition, the precipitation of carbonate minerals has decreased the concentration of Ca2+, Mg2+, and HCO3−, albeit to a limited extent. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0883-2927 | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | no | |||
| Call Number | THL @ christoph.kuells @ Zhao201749 | Serial | 182 | ||
| Permanent link to this record | |||||